:root {
  --paper: #fbf6ec;
  --card: #ffffff;
  --ink: #1d2738;
  --ink-2: #4a5568;
  --ink-3: #8a93a3;
  --line: #e6dfd0;
  --good: #2b8a3e;
  --bad: #e03131;
  --star: #f59f00;
  --c: #2f6fdf; /* unit accent, set per unit */
  --radius: 18px;
  --shadow: 0 2px 0 rgba(29, 39, 56, .08), 0 8px 24px rgba(29, 39, 56, .06);
  font-family: -apple-system, "PingFang TC", "Noto Sans TC", "Microsoft JhengHei", system-ui, sans-serif;
  color: var(--ink);
}

* { box-sizing: border-box; }
[hidden] { display: none !important; }
html, body { margin: 0; }
body {
  background: var(--paper);
  min-height: 100vh;
  min-height: 100dvh;
  overscroll-behavior-y: contain;
  -webkit-text-size-adjust: 100%;
}
button, a, .chip, .bin, .px { -webkit-tap-highlight-color: transparent; }
button, .chip, .nav-btn, .icon-btn, .key, .bulb, .lamp, .way {
  -webkit-user-select: none;
  user-select: none;
  -webkit-touch-callout: none;
}
button { font: inherit; color: inherit; cursor: pointer; }
button:disabled { cursor: default; }
/* fast double taps on controls must not zoom the page on iPad; draggable parts set
   touch-action: none on their own class, which wins over this */
button, a, [role="button"], input, label, summary { touch-action: manipulation; }
a { color: inherit; }
:focus-visible { outline: 3px solid var(--c); outline-offset: 2px; }

/* ---------- shared bits ---------- */

.en {
  display: inline-block;
  margin-left: .3em;
  padding: 0 .4em;
  border-radius: 6px;
  background: color-mix(in srgb, var(--c) 12%, white);
  color: color-mix(in srgb, var(--c) 75%, black);
  font-size: .68em;
  font-weight: 600;
  letter-spacing: .01em;
  line-height: 1.5;
  vertical-align: .12em;
  white-space: nowrap;
}
.term { color: color-mix(in srgb, var(--c) 85%, black); }

.shake { animation: shake .4s cubic-bezier(.36, .07, .19, .97) both; }
@keyframes shake {
  20%, 80% { translate: -3px 0; }
  40%, 60% { translate: 5px 0; }
  50% { translate: -5px 0; }
}
.pop { animation: pop .35s ease-out; }
@keyframes pop { 50% { scale: 1.12; } }
.glow { animation: glow 1.4s ease-in-out infinite; }
@keyframes glow {
  0%, 100% { box-shadow: 0 0 0 0 color-mix(in srgb, var(--c) 45%, transparent); }
  50% { box-shadow: 0 0 0 8px color-mix(in srgb, var(--c) 0%, transparent); }
}
@media (prefers-reduced-motion: reduce) {
  .glow, .pop, .shake { animation: none; }
}

.hint { margin: .6rem 0 0; color: var(--ink-3); font-size: .95rem; text-align: center; }

.go, .controls button, .dl, .option, .way {
  min-height: 52px;
  padding: .6rem 1.2rem;
  border: 2px solid var(--line);
  border-radius: 14px;
  background: var(--card);
  font-size: 1.1rem;
  font-weight: 700;
  box-shadow: 0 3px 0 var(--line);
  transition: transform .08s, box-shadow .08s, background .2s;
}
.go:not(:disabled):active, .controls button:not(:disabled):active, .dl:not(:disabled):active,
.option:not(:disabled):active, .way:not(:disabled):active { transform: translateY(2px); box-shadow: 0 1px 0 var(--line); }
.go { background: var(--c); border-color: var(--c); color: white; box-shadow: 0 3px 0 color-mix(in srgb, var(--c) 70%, black); }
.go:disabled { opacity: .45; }

.token {
  position: absolute;
  left: 0; top: 0;
  z-index: 5;
  padding: .2rem .55rem;
  border-radius: 10px;
  background: var(--c);
  color: white;
  font-weight: 800;
  font-size: 1.2rem;
  pointer-events: none;
}

/* ---------- home ---------- */

.portal-link {
  position: absolute;
  top: max(.5rem, env(safe-area-inset-top));
  left: max(.5rem, env(safe-area-inset-left));
  display: grid;
  place-items: center;
  width: 48px; height: 48px;
  border-radius: 50%;
  color: var(--ink-2);
}
.portal-link svg { width: 28px; height: 28px; }
.portal-link:active { background: rgba(0, 0, 0, .06); }

.home {
  position: relative;
  max-width: 1100px;
  margin: 0 auto;
  padding: max(1.5rem, env(safe-area-inset-top)) 16px max(1.5rem, env(safe-area-inset-bottom));
}
.home-head { text-align: center; padding: 1.2rem 3rem .4rem; }
.home-head h1 { margin: 0; font-size: clamp(2rem, 5vw, 3rem); font-weight: 900; letter-spacing: .04em; }
.home-head .sub { margin: .4rem 0 0; color: var(--ink-2); font-size: 1.05rem; }

.units {
  list-style: none;
  margin: 1.6rem 0 0;
  padding: 0;
  display: grid;
  grid-template-columns: repeat(auto-fill, minmax(min(100%, 240px), 1fr));
  gap: 16px;
}
.unit-card {
  position: relative;
  display: flex;
  flex-direction: column;
  height: 100%;
  padding: 1.2rem 1.2rem 1rem;
  border-radius: var(--radius);
  background: var(--card);
  border: 2px solid transparent;
  border-top: 8px solid var(--c);
  box-shadow: var(--shadow);
  text-decoration: none;
  transition: transform .12s;
}
a.unit-card:active { transform: scale(.98); }
.unit-no {
  position: absolute; top: .8rem; right: 1rem;
  color: color-mix(in srgb, var(--c) 40%, white);
  font-size: 1.8rem; font-weight: 900;
}
.unit-icon { font-size: 2.6rem; line-height: 1; }
.unit-title { margin-top: .6rem; font-size: 1.35rem; font-weight: 800; }
.unit-en { color: var(--c); font-size: .9rem; font-weight: 700; }
.unit-desc { margin-top: .3rem; color: var(--ink-2); flex: 1; }
.unit-stars { margin-top: .6rem; color: var(--star); font-size: 1.2rem; letter-spacing: .1em; }
.unit-stars .dim { color: #e9e2d2; }
.unit-card.full { border-color: color-mix(in srgb, var(--star) 50%, white); }
.unit-card.soon { --c: #adb5bd; opacity: .7; box-shadow: none; border-style: dashed; border-top-style: solid; }
.soon-tag {
  align-self: flex-start;
  margin-top: .6rem; padding: .1rem .6rem;
  border-radius: 99px;
  background: #e9ecef; color: var(--ink-2);
  font-size: .85rem; font-weight: 700;
}
.foot { margin-top: 2rem; text-align: center; color: var(--ink-3); font-size: .9rem; }
.foot p { margin: 0 0 .3rem; }
.foot a { color: var(--ink-2); text-underline-offset: 2px; }

/* ---------- lesson ---------- */

.lesson {
  display: flex;
  flex-direction: column;
  height: 100vh;
  height: 100dvh;
}
.bar {
  display: flex;
  align-items: center;
  gap: .6rem;
  padding: max(.5rem, env(safe-area-inset-top)) max(.6rem, env(safe-area-inset-right)) .5rem max(.6rem, env(safe-area-inset-left));
  background: var(--card);
  border-bottom: 1px solid var(--line);
}
.icon-btn {
  display: grid; place-items: center;
  flex: none;
  width: 48px; height: 48px;
  border: 0; border-radius: 12px;
  background: transparent;
  color: var(--ink-2);
  font-size: 1.4rem;
}
.icon-btn svg { width: 26px; height: 26px; }
.back-units {
  display: inline-flex; align-items: center; flex: none;
  min-height: 44px; padding: 0 .9rem;
  border: 2px solid var(--line); border-radius: 99px;
  background: var(--card); color: var(--ink-2);
  font-weight: 800; text-decoration: none; white-space: nowrap;
  -webkit-tap-highlight-color: transparent; -webkit-user-select: none; user-select: none;
}
.back-units:active { background: rgba(0, 0, 0, .06); }
.icon-btn:active { background: rgba(0, 0, 0, .06); }
.say.talking { background: color-mix(in srgb, var(--c) 15%, white); }
.bar-title { font-weight: 800; font-size: 1.1rem; white-space: nowrap; overflow: hidden; text-overflow: ellipsis; }
.dots { flex: 1; display: flex; justify-content: center; gap: 0; min-width: 0; }
/* each dot is a 32px tap target; the visible 14px dot is drawn by ::after */
.dots .dot { position: relative; flex: none; width: 32px; height: 32px; border-radius: 8px; }
.dots .dot::after { content: ''; position: absolute; inset: 9px; border-radius: 50%; background: var(--line); }
.dots .dot.play::after { border-radius: 4px; }
.dots .dot.got::after { background: var(--star); }
.dots .dot.here::after { outline: 3px solid var(--c); outline-offset: 2px; }
@media (max-width: 600px) { .dots { display: none; } .bar-title { flex: 1; } }

.slide {
  flex: 1;
  overflow-y: auto;
  -webkit-overflow-scrolling: touch;
  width: 100%;
  max-width: 1200px;
  margin: 0 auto;
  padding: 1.4rem 16px 1rem;
  display: flex;
  flex-direction: column;
  gap: 1.2rem;
}
.words h2 { margin: 0; font-size: clamp(1.6rem, 4vw, 2.2rem); font-weight: 900; color: var(--c); }
.words .text { margin: .6rem 0 0; font-size: clamp(1.15rem, 2.6vw, 1.4rem); line-height: 1.8; }
.star-note { margin: .6rem 0 0; color: var(--ink-3); font-weight: 700; }
.star-note.got { color: var(--star); }
.star-row { display: flex; align-items: center; flex-wrap: wrap; gap: 8px 14px; margin-top: .6rem; }
.star-row .star-note { margin: 0; }
.redo { min-height: 44px; padding: 0 16px; border: 2px solid var(--line); border-radius: 99px; background: var(--card); color: var(--ink-2); font-weight: 800; }
.redo:active { background: rgba(0, 0, 0, .06); }
.stage { position: relative; flex: 1; display: flex; flex-direction: column; justify-content: flex-start; padding-top: .4rem; }

@media (min-width: 900px) and (orientation: landscape) {
  .slide.has-widget { flex-direction: row; align-items: center; gap: 2.4rem; }
  .slide.has-widget .words { flex: 0 0 34%; }
  .slide.has-widget .stage { min-width: 0; align-self: stretch; justify-content: center; padding-top: 0; }
}

.nav {
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: .6rem;
  padding: .6rem max(16px, env(safe-area-inset-right)) max(.6rem, env(safe-area-inset-bottom)) max(16px, env(safe-area-inset-left));
  background: var(--card);
  border-top: 1px solid var(--line);
}
.nav-btn {
  display: inline-flex; align-items: center; justify-content: center;
  min-height: 52px;
  padding: .5rem 1.4rem;
  border-radius: 14px;
  border: 2px solid var(--line);
  background: var(--card);
  font-size: 1.15rem; font-weight: 800;
  text-decoration: none;
  box-shadow: 0 3px 0 var(--line);
}
.nav-btn:active { transform: translateY(2px); box-shadow: 0 1px 0 var(--line); }
.nav-btn.next { background: var(--c); border-color: var(--c); color: white; box-shadow: 0 3px 0 color-mix(in srgb, var(--c) 70%, black); }
.nav-btn.hidden { visibility: hidden; }
.page-no { display: flex; flex-direction: column; align-items: center; color: var(--ink-3); font-weight: 700; }
.key-hint { font-size: .75rem; font-weight: 600; }

/* ---------- static art ---------- */

.art { display: grid; place-items: center; min-height: 220px; }
.art-row { display: flex; flex-wrap: wrap; align-items: center; justify-content: center; gap: .3em; font-size: clamp(3rem, 9vw, 5.5rem); }
.art-arrow, .art-eq, .art-dash { color: var(--ink-3); font-size: .55em; font-weight: 900; }
.art-wave { color: var(--c); font-size: .5em; font-weight: 900; animation: wave 1.2s ease-in-out infinite; }
@keyframes wave { 50% { opacity: .3; } }
.art-heart { font-size: .6em; }

.platter { position: relative; width: 240px; height: 240px; border-radius: 24px; background: #495057; box-shadow: var(--shadow); }
.platter-disc {
  position: absolute; inset: 20px;
  border-radius: 50%;
  background: repeating-radial-gradient(circle, #ced4da 0 3px, #adb5bd 3px 6px), #ced4da;
  animation: spin 1.2s linear infinite;
}
.platter-disc::after { content: ''; position: absolute; inset: 42%; border-radius: 50%; background: #495057; }
.platter-disc::before { content: ''; position: absolute; left: 50%; top: 8%; width: 3px; height: 30%; background: var(--c); }
.platter-arm {
  position: absolute; right: 18px; bottom: 30px;
  width: 110px; height: 12px; border-radius: 6px;
  background: #f1f3f5;
  transform-origin: right center; rotate: 35deg;
  animation: arm 2.4s ease-in-out infinite;
}
@keyframes spin { to { rotate: 360deg; } }
@keyframes arm { 50% { rotate: 20deg; } }

.cells { display: grid; grid-template-columns: repeat(6, 44px); gap: 8px; padding: 18px; border-radius: 18px; background: #343a40; }
.cells i { height: 44px; border-radius: 8px; background: #495057; }
.cells i:nth-child(3n+1), .cells i:nth-child(7n) { background: var(--c); box-shadow: 0 0 12px var(--c); animation: wave 2s infinite; }

.ants { display: grid; grid-template-columns: repeat(10, 1fr); gap: 4px; font-size: 1.8rem; max-width: 420px; }
.ants span:nth-child(odd) { animation: wave 1s infinite; }

/* ---------- sort ---------- */

.w-sort { display: flex; flex-direction: column; gap: 14px; }
.tray {
  display: flex; flex-wrap: wrap; justify-content: center; gap: 10px;
  min-height: 64px; padding: 10px;
  border-radius: var(--radius);
  background: color-mix(in srgb, var(--c) 6%, var(--paper));
  border: 2px dashed var(--line);
}
.sort-intro { display: flex; flex-direction: column; align-items: center; gap: 4px; }
.ip-parts { display: flex; align-items: flex-end; gap: 4px; font-family: ui-monospace, Menlo, monospace; }
.ip-parts span { display: flex; flex-direction: column; align-items: center; padding: 4px 10px; border-radius: 10px; background: var(--card); border: 2px solid var(--line); }
.ip-parts b { font-size: 1.5rem; color: var(--c); }
.ip-parts small { font-family: -apple-system, sans-serif; font-weight: 700; color: var(--ink-3); font-size: .75rem; }
.ip-parts i { font-style: normal; font-size: 1.6rem; font-weight: 900; padding-bottom: 14px; }
.sort-intro p { margin: 0; font-weight: 700; color: var(--ink-2); }
.bins { display: grid; grid-template-columns: repeat(var(--n), 1fr); gap: 10px; }
@media (max-width: 560px) { .bins { grid-template-columns: repeat(min(var(--n), 2), 1fr); } }
.bin {
  min-height: 150px;
  padding: 10px;
  border-radius: var(--radius);
  background: var(--card);
  border: 3px solid var(--line);
  transition: border-color .15s, background .15s;
}
.bin.over { border-color: var(--c); background: color-mix(in srgb, var(--c) 8%, white); }
.bin-head { display: flex; flex-direction: column; align-items: center; gap: 2px; font-weight: 800; text-align: center; font-size: 1.05rem; }
.bin-icon { font-size: 2rem; }
.bin-items { display: flex; flex-wrap: wrap; justify-content: center; gap: 6px; margin-top: 8px; }

.chip {
  display: inline-flex; align-items: center; gap: .4rem;
  min-height: 52px;
  padding: .45rem .9rem;
  border: 2px solid var(--line);
  border-radius: 14px;
  background: var(--card);
  font-size: 1.1rem; font-weight: 700;
  line-height: 1.3;
  text-align: left;
  box-shadow: 0 3px 0 var(--line);
  touch-action: none;
  transition: transform .2s, box-shadow .2s;
}
.chip-icon { font-size: 1.6rem; }
.usb-ico { display: inline-block; width: 1.2em; height: 1.2em; vertical-align: -.2em; }
.chip .en { display: block; margin: .1rem 0 0; width: fit-content; }
.chip.dragging { transition: none; z-index: 10; position: relative; box-shadow: 0 12px 24px rgba(0, 0, 0, .18); cursor: grabbing; }
.chip.selected { border-color: var(--c); background: color-mix(in srgb, var(--c) 10%, white); }
.chip.placed { min-height: 0; padding: .25rem .6rem; font-size: .95rem; box-shadow: none; border-color: color-mix(in srgb, var(--good) 40%, white); background: #ebfbee; touch-action: auto; }
.chip.placed .chip-icon { font-size: 1.2rem; }

/* ---------- choice ---------- */

.w-choice { display: flex; flex-direction: column; gap: 14px; max-width: 640px; width: 100%; margin: 0 auto; }
.question { margin: 0; font-size: clamp(1.25rem, 3vw, 1.6rem); font-weight: 800; line-height: 1.6; }
.options { display: flex; flex-direction: column; gap: 10px; }
.option { text-align: left; font-size: 1.2rem; padding: .8rem 1.1rem; }
.option.right { border-color: var(--good); background: #ebfbee; }
.option.wrong { border-color: var(--bad); background: #fff5f5; opacity: .55; }
.explain { margin: 0; padding: .8rem 1rem; border-radius: 14px; background: #fff9db; font-size: 1.1rem; line-height: 1.7; }

/* ---------- order ---------- */

.w-order { display: flex; flex-direction: column; gap: 14px; }
.seq {
  list-style: none; counter-reset: n;
  margin: 0; padding: 10px;
  min-height: 72px;
  display: flex; flex-direction: column; gap: 8px;
  border-radius: var(--radius);
  background: var(--card);
  border: 2px dashed var(--line);
}
.seq li { counter-increment: n; display: flex; align-items: center; gap: 10px; }
.seq li::before {
  content: counter(n);
  display: grid; place-items: center; flex: none;
  width: 34px; height: 34px; border-radius: 50%;
  background: var(--c); color: white; font-weight: 900;
}
.pool { display: flex; flex-wrap: wrap; justify-content: center; gap: 10px; }
.pool .chip.placed { display: none; }
.seq .chip.placed { font-size: 1.05rem; padding: .35rem .8rem; }
.ord-hole { flex: 1; display: flex; align-items: center; min-height: 48px; padding: 0 12px; border: 2px dashed var(--line); border-radius: 12px; color: var(--ink-3); font-weight: 700; }
.ord-slot.over .ord-hole { border-color: var(--c); background: color-mix(in srgb, var(--c) 8%, white); }
.seq li.ord-slot:not(.ord-done)::before { background: var(--line); color: var(--ink-2); }
.ord-hint { margin: 0; text-align: center; color: var(--ink-2); font-weight: 700; }

/* ---------- binary ---------- */

.w-binary { display: flex; flex-direction: column; align-items: center; gap: 18px; }
.w-binary .target { margin: 0; font-size: 1.4rem; font-weight: 800; display: flex; align-items: center; gap: .5rem; }
.w-binary .big { font-size: 3rem; color: var(--c); }
.w-binary .rdots { display: inline-flex; gap: 6px; margin-left: .6rem; }
.w-binary .rdots i { width: 12px; height: 12px; border-radius: 50%; background: var(--line); }
.w-binary .rdots i.ok { background: var(--good); }
.bulbs { display: flex; gap: clamp(8px, 2vw, 18px); }
.bulb {
  display: flex; flex-direction: column; align-items: center; gap: 4px;
  width: clamp(68px, 15vw, 104px);
  padding: 10px 4px;
  border: 3px solid var(--line); border-radius: 18px;
  background: #2b2f36; color: white;
  transition: background .2s, border-color .2s;
}
.bulb .bit { font-size: 1.6rem; font-weight: 900; font-family: ui-monospace, Menlo, monospace; }
.bulb .bico { font-size: 2.6rem; filter: grayscale(1) brightness(.5); transition: filter .2s; }
.bulb .val { font-size: 1.2rem; font-weight: 800; color: #adb5bd; }
.bulb.on { background: #fff3bf; color: var(--ink); border-color: var(--star); }
.bulb.on .bico { filter: drop-shadow(0 0 12px #ffd43b); }
.bulb.on .val { color: var(--ink); }
.w-binary .sum { margin: 0; font-size: 1.4rem; }
.w-binary .code { font-family: ui-monospace, Menlo, monospace; font-weight: 800; color: var(--c); letter-spacing: .1em; }

/* bits and bytes: typed letters stored as bytes, and 8 switches that make one byte */
.by-box { display: flex; flex-direction: column; gap: 8px; min-width: 0; }
.by-h { margin: 4px 0 0; font-weight: 800; }
.by-keys { display: flex; flex-wrap: wrap; gap: 6px; }
.by-keys .option { min-width: 48px; min-height: 48px; padding: 0 10px; font-size: 1.2rem; }
.by-strip { display: flex; gap: 8px; min-height: 92px; padding: 8px; overflow-x: auto; border-radius: 14px; background: var(--card); border: 2px dashed var(--line); }
.by-empty { margin: auto; color: var(--ink-3); font-weight: 700; }
.by-char { flex: none; display: flex; flex-direction: column; align-items: center; gap: 3px; padding: 4px 8px; border-radius: 10px; background: color-mix(in srgb, var(--c) 8%, white); }
.by-char b { font-size: 1.4rem; }
.by-byte { padding: 1px 6px; border-radius: 6px; background: white; border: 1px solid var(--line); font-family: ui-monospace, Menlo, monospace; font-size: .85rem; }
.by-char small { color: var(--ink-3); font-weight: 700; font-size: .75rem; }
.by-count { margin: 0; font-weight: 700; color: var(--ink-2); }
.by-count b { color: var(--c); font-size: 1.15rem; }
.by-sw { display: flex; gap: 4px; flex-wrap: wrap; padding: 8px; border-radius: 14px; border: 3px solid var(--c); width: fit-content; }
.by-bit { display: flex; flex-direction: column; align-items: center; justify-content: center; width: 44px; height: 56px; border: 2px solid var(--line); border-radius: 10px; background: var(--card); font-family: ui-monospace, Menlo, monospace; }
.by-bit b { font-size: 1.4rem; }
.by-bit small { color: var(--ink-3); font-size: .7rem; font-family: inherit; }
.by-bit.on { border-color: var(--c); background: var(--c); color: white; }
.by-bit.on small { color: rgba(255, 255, 255, .8); }
.by-read { margin: 0; font-family: ui-monospace, Menlo, monospace; font-weight: 700; }
.by-read b { color: var(--c); font-size: 1.3rem; }

/* ---------- pixel grids (pixels, race, printer) ---------- */

.pxgrid {
  display: grid;
  grid-template-columns: repeat(var(--cols), 1fr);
  gap: 3px;
  padding: 6px;
  border-radius: 12px;
  background: #343a40;
  touch-action: none;
}
.px { display: block; border-radius: 3px; background: #495057; aspect-ratio: 1; }
.px.on { background: var(--px, var(--c)); }
.w-pixels, .w-printer { display: flex; flex-wrap: wrap; justify-content: center; align-items: center; gap: 18px; }
.w-pixels figure, .w-printer figure { margin: 0; text-align: center; }
.w-pixels figcaption, .w-printer figcaption { font-weight: 800; margin-bottom: 6px; }
.w-pixels .model { width: 150px; }
.w-pixels .canvas { width: min(300px, 70vw); }
.w-pixels .canvas .px { cursor: pointer; }
.w-pixels .hint, .w-printer .hint { flex-basis: 100%; }

/* ---------- rgb ---------- */

.w-rgb { display: flex; flex-wrap: wrap; justify-content: center; align-items: center; gap: 24px; }
.mix { position: relative; width: 240px; height: 230px; border-radius: 20px; background: #111; overflow: hidden; isolation: isolate; }
.mix i { position: absolute; width: 120px; height: 120px; border-radius: 50%; mix-blend-mode: screen; opacity: .08; transition: opacity .25s; }
.mix i.on { opacity: 1; }
.mix .r { background: #f00; left: 30px; top: 30px; }
.mix .g { background: #0f0; left: 90px; top: 30px; }
.mix .b { background: #00f; left: 60px; top: 82px; }
.w-rgb .side { display: flex; flex-direction: column; gap: 14px; align-items: center; }
.w-rgb .target, .w-rgb .result { margin: 0; font-size: 1.3rem; display: flex; align-items: center; gap: .4rem; }
.swatch { display: inline-block; width: 36px; height: 36px; border-radius: 10px; border: 2px solid var(--line); vertical-align: middle; }
.lamps { display: flex; gap: 10px; }
.lamp {
  width: 76px; height: 76px; border-radius: 50%;
  border: 4px solid; background: white;
  font-size: 1.3rem; font-weight: 900;
}
.lamp-0 { border-color: #fa5252; color: #c92a2a; }
.lamp-1 { border-color: #40c057; color: #2b8a3e; }
.lamp-2 { border-color: #4c6ef5; color: #364fc7; }
.lamp-0.on { background: #fa5252; color: white; box-shadow: 0 0 18px #fa5252; }
.lamp-1.on { background: #40c057; color: white; box-shadow: 0 0 18px #40c057; }
.lamp-2.on { background: #4c6ef5; color: white; box-shadow: 0 0 18px #4c6ef5; }

/* ---------- keys ---------- */

.w-keys {
  position: relative;
  display: grid;
  grid-template-columns: 1fr auto 1fr;
  grid-template-areas: "kb cpu screen" "kbl . screenl" "cap cap cap";
  align-items: center;
  gap: 10px 18px;
}
.w-keys .kb { grid-area: kb; display: grid; grid-template-columns: repeat(3, 1fr); gap: 8px; padding: 12px; border-radius: 16px; background: #dee2e6; }
.key {
  min-height: 60px;
  border: 0; border-radius: 10px;
  background: white;
  font-size: 1.6rem; font-weight: 800;
  box-shadow: 0 4px 0 #adb5bd;
}
.key:active { transform: translateY(3px); box-shadow: 0 1px 0 #adb5bd; }
.stage-lbl { text-align: center; font-weight: 800; color: var(--ink-2); }
.kb-lbl { grid-area: kbl; }
.screen-lbl { grid-area: screenl; }
.w-keys .cpu { grid-area: cpu; display: flex; flex-direction: column; align-items: center; padding: 12px; border-radius: 16px; background: color-mix(in srgb, var(--c) 12%, white); font-size: 2.6rem; }
.w-keys .cpu small { font-size: .9rem; font-weight: 800; }
.w-keys .screen {
  grid-area: screen;
  min-height: 130px;
  padding: 14px;
  border: 10px solid #343a40; border-radius: 14px;
  background: #f8f9fa;
  font-family: ui-monospace, Menlo, monospace;
  font-size: 2rem; font-weight: 700;
  word-break: break-all;
}
.caret { display: inline-block; width: 3px; height: 1.1em; background: var(--ink); vertical-align: -.15em; animation: wave 1s steps(1) infinite; }
.w-keys .caption { grid-area: cap; margin: 0; text-align: center; font-size: 1.25rem; }
@media (max-width: 640px) {
  .w-keys { grid-template-columns: 1fr; grid-template-areas: "screen" "screenl" "cpu" "kb" "kbl" "cap"; }
  .w-keys .cpu { flex-direction: row; gap: .5rem; justify-self: center; font-size: 2rem; }
}

/* ---------- mouse ---------- */

.w-mouse { display: flex; flex-direction: column; align-items: center; gap: 10px; }
.w-mouse .screen {
  position: relative;
  width: min(100%, 520px); aspect-ratio: 16 / 9;
  border: 10px solid #343a40; border-radius: 14px;
  background: linear-gradient(160deg, #e7f5ff, #d0ebff);
  overflow: hidden;
}
.w-mouse .star { position: absolute; translate: -50% -50%; font-size: 2rem; }
.cursor { position: absolute; width: 28px; height: 28px; fill: white; stroke: var(--ink); stroke-width: 1.6; filter: drop-shadow(0 2px 2px rgba(0,0,0,.3)); }
.w-mouse .readout { margin: 0; font-weight: 800; font-size: 1.1rem; min-height: 1.6em; }
.desk {
  position: relative;
  width: min(100%, 520px); height: 180px;
  border-radius: 18px;
  background: repeating-linear-gradient(90deg, #c8a27a 0 40px, #c39b71 40px 80px);
  touch-action: none;
  cursor: grab;
}
.desk .mouse { position: absolute; translate: -50% -50%; font-size: 3rem; pointer-events: none; }

/* ---------- touch ---------- */

.w-touch { display: flex; flex-direction: column; align-items: center; gap: 10px; }
.w-touch .pad {
  position: relative;
  width: min(100%, 520px); aspect-ratio: 7 / 5;
  border: 14px solid #212529; border-radius: 26px;
  background: #f1f3f5;
  overflow: hidden;
  touch-action: none;
}
.hline, .vline { position: absolute; background: #dee2e6; transition: background .15s, box-shadow .15s; }
.hline { left: 0; right: 0; height: 3px; translate: 0 -50%; }
.vline { top: 0; bottom: 0; width: 3px; translate: -50% 0; }
.hline.lit, .vline.lit { background: var(--c); box-shadow: 0 0 8px var(--c); }
.w-touch .cat { position: absolute; translate: -50% -50%; font-size: 2.4rem; pointer-events: none; transition: top .3s, left .3s; }
.w-touch .dot { position: absolute; width: 22px; height: 22px; translate: -50% -50%; border-radius: 50%; background: var(--c); opacity: 0; pointer-events: none; }
.w-touch .dot.show { opacity: .8; }
.w-touch .readout { margin: 0; font-weight: 800; font-size: 1.15rem; text-align: center; }

/* ---------- power ---------- */

.w-power { display: flex; flex-direction: column; gap: 14px; }
.w-power .step { margin: 0; font-size: 1.25rem; font-weight: 800; min-height: 1.8em; }
.pc { position: relative; display: grid; grid-template-columns: 1fr 1fr; gap: 12px; padding: 14px; border-radius: 20px; background: #343a40; }
.area { min-height: 150px; padding: 10px; border-radius: 14px; background: #f8f9fa; transition: background .3s; }
.area-lbl { font-weight: 800; font-size: 1.05rem; }
.area-lbl .en { display: inline-block; }
.things { display: flex; flex-wrap: wrap; gap: 6px; margin-top: 8px; font-size: 2.6rem; }
.thing { transition: opacity .6s, scale .6s; }
.thing.vanish { opacity: 0; scale: .3; }
.off-veil { position: absolute; inset: 0; display: grid; place-items: center; border-radius: 20px; background: rgba(15, 18, 24, .82); color: white; font-size: 3rem; opacity: 0; pointer-events: none; transition: opacity .4s; }
.pc.off .off-veil { opacity: 1; }
.controls { display: flex; flex-wrap: wrap; justify-content: center; gap: 10px; }
.controls button:disabled { opacity: .4; }
.controls button.glow { border-color: var(--c); }

/* ---------- cloud ---------- */

.w-cloud { position: relative; display: flex; flex-direction: column; gap: 12px; }
.w-cloud .step { margin: 0; font-size: 1.2rem; font-weight: 800; min-height: 3.4em; }
.sky {
  display: flex; align-items: center; gap: 10px; justify-content: center;
  min-height: 110px; padding: 10px;
  border-radius: 60px;
  background: linear-gradient(#e7f5ff, #d0ebff);
  border: 3px dashed #a5d8ff;
}
.sky.over { border-color: var(--c); }
.cloud-icon { font-size: 3.4rem; }
.cloud-lbl { font-weight: 800; color: var(--ink-2); }
.sky .things { margin: 0; }
.phones { display: grid; grid-template-columns: 1fr 1fr; gap: 14px; }
.device { display: flex; flex-direction: column; align-items: center; gap: 8px; padding: 10px; border-radius: 22px; background: #212529; color: white; transition: filter .4s, opacity .4s; }
.dev-lbl { font-weight: 800; }
.dev-screen { display: grid; place-items: center; width: 100%; min-height: 110px; border-radius: 12px; background: #f8f9fa; color: var(--ink); font-size: 2.6rem; }
.device .chip.photo { font-size: 2rem; }
.device .chip.photo.placed { opacity: .35; }
.device.broken { filter: grayscale(1); opacity: .5; }
.device.broken .dev-screen::after { content: '💦'; }
.dl { color: var(--ink); font-size: 1rem; }
.dl:disabled { opacity: .4; }
.dl.glow { border-color: var(--c); }

/* ---------- packets ---------- */

.w-packets { display: flex; flex-direction: column; gap: 12px; }
.w-packets .msg { margin: 0; font-size: 1.2rem; }
.net { position: relative; width: 100%; aspect-ratio: 600 / 220; border-radius: 18px; background: var(--card); border: 2px solid var(--line); }
.net > svg { position: absolute; inset: 0; width: 100%; height: 100%; }
.net line { stroke: #ced4da; stroke-width: 4; stroke-linecap: round; vector-effect: non-scaling-stroke; }
.node { position: absolute; translate: -50% -50%; font-size: clamp(1.4rem, 4vw, 2rem); }
.node.end { font-size: clamp(2rem, 6vw, 3rem); }
.router-ico { display: block; width: 1.3em; height: 1.1em; }
.packet, .packet-card { display: inline-flex; align-items: center; gap: .3rem; font-weight: 800; }
.packet { position: absolute; translate: -50% -50%; padding: .15rem .5rem; border-radius: 10px; background: #fff3bf; border: 2px solid var(--star); font-size: .95rem; white-space: nowrap; }
.packet i, .packet-card i { display: grid; place-items: center; width: 1.5em; height: 1.5em; border-radius: 50%; background: var(--c); color: white; font-style: normal; font-size: .85em; }
.w-packets .go { align-self: center; }
.arrived p { margin: 0 0 8px; font-weight: 800; }
.packet-card.placed { opacity: .35; }
.pk-rebuild p { margin: 0 0 8px; font-weight: 800; }
.pk-slots { list-style: none; display: flex; flex-wrap: wrap; justify-content: center; gap: 8px; margin: 0; padding: 0; }
.pk-slot { display: inline-flex; align-items: center; gap: .4rem; min-width: 96px; min-height: 52px; padding: 0 12px; border: 2px dashed var(--line); border-radius: 14px; background: var(--card); font-weight: 800; font-size: 1.2rem; color: var(--ink-3); }
.pk-slot i { display: grid; place-items: center; width: 1.5em; height: 1.5em; border-radius: 50%; background: var(--line); color: var(--ink-2); font-style: normal; font-size: .75em; }
.pk-slot.over { border-color: var(--c); background: color-mix(in srgb, var(--c) 8%, white); }
.pk-slot.pk-in { border-style: solid; border-color: color-mix(in srgb, var(--good) 40%, white); background: #ebfbee; color: var(--ink); }
.pk-slot.pk-in i { background: var(--c); color: white; }
.w-packets .pk-done { margin: 8px 0 0; text-align: center; color: var(--c); font-size: 1.4rem; }

/* routing: you are each router; the table says where the packet goes next */
.w-route { display: flex; flex-direction: column; align-items: center; gap: 8px; }
.rt-pkt { margin: 0; font-weight: 800; font-size: 1.1rem; }
.rt-pkt mark, .rt-table u { background: #ffe066; border-radius: 4px; padding: 0 3px; text-decoration: none; }
.rt-net { position: relative; width: min(100%, 640px); aspect-ratio: 640 / 300; border-radius: 18px; background: var(--card); border: 2px solid var(--line); }
.rt-net > svg { position: absolute; inset: 0; width: 100%; height: 100%; }
.rt-net line { stroke: #dee2e6; stroke-width: 5; stroke-linecap: round; }
.rt-net line.rt-used { stroke: var(--c); }
.rt-node { position: absolute; translate: -50% -50%; display: flex; flex-direction: column; align-items: center; min-width: 48px; min-height: 48px; padding: 2px 4px; border: 2px solid transparent; border-radius: 12px; background: var(--card); font-size: 1.8rem; line-height: 1; }
.rt-node small { font-size: .7rem; font-weight: 800; color: var(--ink-2); margin-top: 2px; }
.rt-node.rt-dev small { font-family: ui-monospace, Menlo, monospace; }
.rt-node.rt-here { border-color: var(--c); background: color-mix(in srgb, var(--c) 12%, white); }
.rt-node.rt-can { border-color: #ffd43b; border-style: dashed; animation: glow 1.4s infinite; }
.rt-box { position: absolute; translate: -50% -110%; font-size: 1.5rem; pointer-events: none; z-index: 2; }
.rt-table { display: flex; flex-wrap: wrap; justify-content: center; gap: 4px 12px; min-height: 2em; font-family: ui-monospace, Menlo, monospace; font-weight: 700; }
.rt-table b { font-family: var(--font, inherit); }
.rt-table span { padding: 2px 8px; border-radius: 8px; background: #f1f3f5; }
.rt-table span.rt-hit { background: color-mix(in srgb, var(--c) 15%, white); outline: 2px solid var(--c); }
.rt-msg { margin: 0; font-weight: 800; text-align: center; }

/* ---------- race ---------- */

.w-race { display: flex; flex-direction: column; align-items: center; gap: 14px; }
.lanes { display: grid; grid-template-columns: 1fr 1fr; gap: 16px; width: 100%; max-width: 560px; }
.lane { margin: 0; text-align: center; }
.lane figcaption { display: flex; flex-direction: column; margin-bottom: 6px; font-size: 1.15rem; }
.lane small { color: var(--ink-2); font-size: .9rem; }
.lane .px { transition: background .15s; }
.lane .time { margin: 6px 0 0; font-family: ui-monospace, Menlo, monospace; font-size: 1.4rem; font-weight: 800; }
.w-race .result { margin: 0; font-size: 1.15rem; line-height: 1.7; text-align: center; min-height: 1.7em; }

/* ---------- printer ---------- */

.w-printer .canvas, .w-printer .paper { width: min(240px, 40vw); }
.w-printer .canvas { --px: var(--c); }
.paper { position: relative; padding: 8px; border-radius: 6px; background: white; box-shadow: var(--shadow); }
.paper .pxgrid { background: white; padding: 0; gap: 2px; }
.paper .px { background: #f8f9fa; border-radius: 50%; }
.paper .px.on { background: #212529; }
.head { position: absolute; width: 26px; height: 18px; translate: -50% -60%; border-radius: 4px; background: var(--c); opacity: 0; transition: top .05s, left .05s; pointer-events: none; }
.head.show { opacity: .9; }
.w-printer .mid { display: flex; flex-direction: column; gap: 10px; }
.lz-beam { position: absolute; left: 4px; right: 4px; height: 3px; translate: 0 -50%; border-radius: 2px; background: #ff3b3b; box-shadow: 0 0 8px #ff3b3b; opacity: 0; transition: top .1s; pointer-events: none; }
.lz-beam.show { opacity: 1; }
.paper .px.lz-charge { background: #fff; box-shadow: inset 0 0 0 2px #ced4da; }
.paper .px.lz-toner { background: #868e96; transition: background .3s; }
.lz-heat { position: absolute; inset: 0; border-radius: 6px; background: radial-gradient(circle, rgba(255, 146, 43, .45), rgba(255, 146, 43, 0) 70%); opacity: 0; transition: opacity .3s; pointer-events: none; }
.lz-heat.show { opacity: 1; }
.paper .head { margin: 8px; }

/* ---------- connect ---------- */

.w-connect { display: flex; flex-direction: column; align-items: center; gap: 12px; }
.scene { position: relative; display: flex; align-items: center; justify-content: space-between; width: min(100%, 460px); padding: 14px 20px; border-radius: 20px; background: var(--card); border: 2px solid var(--line); font-size: 3.4rem; }
.scene .link { flex: 1; height: 6px; margin: 0 14px; border-radius: 3px; background: repeating-linear-gradient(90deg, #dee2e6 0 10px, transparent 10px 18px); }
.scene .globe { filter: grayscale(1); opacity: .5; transition: filter .3s, opacity .3s; }
.scene.online .globe { filter: none; opacity: 1; }
.scene.online .link { animation: flow .6s linear infinite; }
.scene.via-cable .link { background: var(--c); height: 8px; }
.scene.via-wifi .link { background: repeating-linear-gradient(90deg, var(--c) 0 6px, transparent 6px 16px); }
.scene.via-cell .link { background: repeating-linear-gradient(90deg, var(--c) 0 14px, transparent 14px 22px); }
.scene.via-sat .link { background: repeating-linear-gradient(90deg, var(--c) 0 4px, transparent 4px 12px); }
@keyframes flow { to { background-position: 32px 0; } }
.where { margin: 0; font-size: 1.25rem; font-weight: 800; text-align: center; }
.status { margin: 0; font-size: 1.1rem; text-align: center; }
.pill { display: inline-block; padding: .05rem .6rem; border-radius: 99px; font-weight: 800; font-size: .95rem; }
.pill.off { background: #e9ecef; color: var(--ink-2); }
.pill.on { background: #d3f9d8; color: var(--good); }
.ways { display: flex; flex-wrap: wrap; justify-content: center; gap: 10px; }
.way { display: inline-flex; align-items: center; gap: .4rem; text-align: left; }
.way.right { border-color: var(--good); background: #ebfbee; }
.way.wrong { border-color: var(--bad); opacity: .5; }
.way-svg { display: block; width: 1.9em; height: 1.9em; flex: none; }

/* ---------- finish ---------- */

.finish {
  position: relative;
  display: flex; flex-direction: column; align-items: center; justify-content: center;
  min-height: 100vh; min-height: 100dvh;
  padding: 24px 16px;
  text-align: center;
  overflow: hidden;
}
.finish h2 { margin: .4rem 0; font-size: clamp(1.8rem, 5vw, 2.6rem); color: var(--c); }
.finish p { font-size: 1.2rem; }
.finish .big-icon { margin: 0; font-size: 5rem; line-height: 1.1; }
.unit-stars.big { font-size: 2.4rem; }
.finish-btns { display: flex; flex-wrap: wrap; justify-content: center; gap: 12px; margin-top: 1rem; }
.finish .fin-ch { margin: .6rem 0 0; font-size: 1.05rem; font-weight: 800; color: var(--ink-2); }
.fin-next { position: relative; display: flex; flex-direction: column; align-items: center; gap: 4px; width: min(100%, 440px); margin-top: .4rem; padding: 14px 18px; border-radius: var(--radius); background: var(--card); border: 2px solid var(--line); border-left: 8px solid var(--c); box-shadow: var(--shadow); }
.fin-next small { color: var(--ink-3); font-weight: 800; }
.fin-next b { font-size: 1.3rem; color: color-mix(in srgb, var(--c) 80%, black); }
.fin-next span { color: var(--ink-2); font-weight: 600; }
.finish .fin-part { margin: 0 0 6px; font-size: 1.05rem; font-weight: 800; color: var(--star); }
.confetti i {
  position: absolute; top: -20px;
  width: 10px; height: 16px; border-radius: 3px;
  background: var(--c);
  animation: fall 3s linear infinite;
}
.confetti i:nth-child(3n) { background: var(--star); }
.confetti i:nth-child(3n+1) { background: #40c057; }
.confetti i:nth-child(4n) { animation-duration: 4s; }
.confetti i:nth-child(5n) { animation-duration: 2.4s; }
@keyframes fall { to { transform: translateY(110vh) rotate(540deg); } }
@media (prefers-reduced-motion: reduce) { .confetti { display: none; } }

/* ---------- portrait iPad: more room below the text, so the tasks grow ---------- */

@media (orientation: portrait) and (min-width: 700px) and (min-height: 900px) {
  .stage { padding-top: 1.4rem; }
  .chip, .way, .option { min-height: 64px; font-size: 1.3rem; }
  .chip-icon { font-size: 2rem; }
  .bin { min-height: 200px; }
  .bin-head { font-size: 1.2rem; }
  .bin-icon { font-size: 2.6rem; }
  .key { min-height: 84px; font-size: 2.2rem; }
  .w-keys .screen { min-height: 190px; font-size: 2.6rem; }
  .w-keys .cpu { font-size: 3.4rem; }
  .w-keys .caption { font-size: 1.5rem; }
  .bulb { width: 130px; }
  .bulb .bico { font-size: 3.4rem; }
  .w-pixels .model { width: 210px; }
  .w-pixels .canvas { width: min(440px, 60vw); }
  .w-printer .canvas, .w-printer .paper { width: min(300px, 38vw); }
  .w-rgb .mix { transform: scale(1.25); margin: 30px; }
  .lamp { width: 92px; height: 92px; font-size: 1.5rem; }
  .w-mouse .screen, .desk, .w-touch .pad { width: min(100%, 680px); }
  .desk { height: 240px; }
  .scene { width: min(100%, 600px); font-size: 4.4rem; }
  .lanes { max-width: 720px; }
  .w-power .step, .w-cloud .step, .where { font-size: 1.4rem; }
  .things { font-size: 3.2rem; }
  .area { min-height: 200px; }
  .dev-screen { min-height: 150px; }
}

/* ---------- home sections ---------- */

.part-title { margin: 2rem 0 0; font-size: 1.3rem; font-weight: 900; color: var(--ink-2); display: flex; align-items: center; gap: .3rem; }
.part-title .en { --c: #868e96; }
.part-title + .units { margin-top: .8rem; }

/* connector drawings in chips and boxes */
.conn { width: 2.4em; height: auto; vertical-align: middle; }
.bin-icon .conn { width: 64px; }
.chip.placed .conn { width: 1.8em; }

/* ---------- labs: a play area plus a task checklist ---------- */

.w-lab { display: grid; grid-template-columns: 1fr minmax(180px, 34%); gap: 14px; align-items: start; }
@media (max-width: 760px) { .w-lab { grid-template-columns: 1fr; } }
/* portrait: the task takes the full width, and the checklist goes below it in columns */
@media (orientation: portrait) {
  .w-lab { grid-template-columns: 1fr; }
  .w-lab > .tasks { display: grid; grid-template-columns: repeat(auto-fill, minmax(220px, 1fr)); gap: 4px 12px; }
  .w-lab > .frame { width: min(100%, 600px); justify-self: center; }
}
.tasks { list-style: none; margin: 0; padding: 10px; display: flex; flex-direction: column; gap: 6px; border-radius: var(--radius); background: var(--card); border: 2px solid var(--line); }
.tasks li { display: flex; align-items: flex-start; gap: .5rem; padding: .3rem .2rem; font-weight: 800; line-height: 1.35; }
.tasks .tick { flex: none; width: 24px; height: 24px; margin-top: 1px; border-radius: 7px; border: 2.5px solid var(--line); }
.tasks li.done .tick { background: var(--good); border-color: var(--good); }
.tasks li.done .tick::after { content: '✓'; display: block; color: white; font-size: 15px; line-height: 19px; text-align: center; }
.tasks li.optional:not(.done) { opacity: .5; }
.tasks .alt { display: block; color: var(--ink-3); font-size: .85rem; font-weight: 600; }
.tasks li.done .alt { color: var(--good); }
.toast {
  position: absolute; left: 50%; bottom: 10px; translate: -50% 0; z-index: 6;
  padding: .45rem .9rem; border-radius: 12px;
  background: var(--ink); color: white; font-weight: 700; white-space: nowrap;
  pointer-events: none;
}

/* mouse playground */
.playground {
  position: relative;
  display: grid; grid-template-columns: repeat(3, 1fr); gap: 10px;
  padding: 30px 12px 48px;
  border-radius: var(--radius);
  background: var(--card); border: 2px solid var(--line);
  touch-action: manipulation;
  -webkit-user-select: none; user-select: none;
}
.playground .cell { position: relative; display: flex; flex-direction: column; align-items: center; justify-content: center; gap: 4px; min-height: 120px; padding: 8px; border-radius: 14px; background: var(--paper); }
.playground .cell.wide { grid-column: span 2; flex-direction: row; flex-wrap: wrap; gap: 14px; }
.playground .cell.wide p { flex-basis: 100%; text-align: center; }
.playground .cell p { margin: 0; color: var(--ink-2); font-weight: 700; font-size: .95rem; }
.obj { border: 0; background: none; font-size: 3rem; line-height: 1.1; padding: 0; -webkit-touch-callout: none; }
.apple { touch-action: none; cursor: grab; position: relative; }
.apple.placed { visibility: hidden; }
.basket.full::after { content: '🍎'; position: absolute; font-size: 1.6rem; translate: -1.6em -.2em; }
.basket { position: relative; padding: 4px 10px; border-radius: 12px; border: 3px dashed transparent; }
.basket.over { border-color: var(--c); }
.arrow { color: var(--ink-3); font-size: 1.6rem; font-weight: 900; }
.scroller { width: 100%; max-width: 120px; height: 84px; overflow-y: auto; border-radius: 10px; background: #e7f5ff; border: 2px solid #a5d8ff; font-size: 1.6rem; text-align: center; line-height: 1.4; touch-action: pan-y; overscroll-behavior: contain; }
.ctx { position: absolute; top: 58%; left: 55%; z-index: 4; display: flex; flex-direction: column; min-width: 110px; padding: 4px; border-radius: 12px; background: white; box-shadow: 0 8px 24px rgba(0,0,0,.2); }
.ctx button { border: 0; background: none; padding: .55rem .7rem; text-align: left; font-size: 1rem; font-weight: 700; border-radius: 8px; }
.ctx button:active { background: var(--paper); }
.coords { position: absolute; top: 6px; right: 12px; font-family: ui-monospace, Menlo, monospace; font-size: .85rem; color: var(--ink-3); }
.tip { position: absolute; z-index: 5; translate: -50% -110%; padding: .15rem .5rem; border-radius: 6px; background: var(--ink); color: white; font-size: .85rem; font-weight: 700; pointer-events: none; }

/* touch photo */
.frame {
  position: relative; overflow: hidden;
  aspect-ratio: 4 / 3;
  border: 14px solid #212529; border-radius: 26px;
  background: #212529;
  touch-action: none;
  -webkit-user-select: none; user-select: none; -webkit-touch-callout: none;
}
.pic { position: absolute; inset: 0; display: grid; place-items: center; background: linear-gradient(160deg, #fff3bf, #d3f9d8); transform-origin: center; will-change: transform; }
.pic.settle { transition: transform .25s ease-out; }
.pic .beast { font-size: clamp(5rem, 16vw, 9rem); pointer-events: none; }
.pic .corner { position: absolute; font-size: 2rem; }
.corner.tl { top: 8px; left: 10px; }
.corner.br { bottom: 8px; right: 10px; }
.photo-cap { position: absolute; left: 0; right: 0; bottom: 0; margin: 0; padding: .6rem 1rem; background: rgba(0,0,0,.6); color: white; font-weight: 700; }
.menu { position: absolute; top: 50%; left: 50%; translate: -50% -50%; z-index: 4; display: flex; flex-direction: column; padding: 6px; border-radius: 14px; background: rgba(255,255,255,.95); box-shadow: 0 8px 24px rgba(0,0,0,.25); }
.menu button { border: 0; background: none; padding: .6rem 1rem; font-size: 1.05rem; font-weight: 700; text-align: left; border-radius: 8px; }
.count { position: absolute; top: 8px; right: 12px; padding: 0 .5rem; border-radius: 99px; background: rgba(0,0,0,.45); color: white; font-weight: 700; font-size: .85rem; }

/* camera app */
.cam { display: flex; flex-direction: column; gap: 8px; padding: 12px; border-radius: 26px; background: #111; color: white; max-width: 520px; width: 100%; justify-self: center; }
.viewfinder { position: relative; aspect-ratio: 4 / 3; border-radius: 12px; overflow: hidden; background: linear-gradient(#a5d8ff 60%, #8ce99a 60%); }
.shot { position: absolute; inset: 0; font-size: clamp(2.4rem, 7vw, 4rem); }
.shot.front { background: linear-gradient(#ffe8cc, #ffd8a8); font-size: clamp(5rem, 14vw, 8rem); }
.rec { position: absolute; top: 8px; left: 50%; translate: -50% 0; padding: .1rem .6rem; border-radius: 6px; background: #e03131; font-weight: 800; }
.flash { position: absolute; inset: 0; background: white; opacity: 0; pointer-events: none; }
.flash.go { animation: flash .35s ease-out; }
@keyframes flash { 0% { opacity: 1; } 100% { opacity: 0; } }
.modes { display: flex; justify-content: center; gap: 18px; }
.modes button { min-height: 44px; border: 0; background: none; color: #adb5bd; font-weight: 800; font-size: 1rem; padding: .3rem .8rem; }
.modes button.on { color: #ffd43b; }
.cam-bar { display: grid; grid-template-columns: 1fr auto 1fr; align-items: center; }
.thumb { position: relative; justify-self: start; width: 64px; height: 48px; border-radius: 10px; background: #343a40; overflow: hidden; }
.thumb b { position: absolute; right: 2px; bottom: 0; z-index: 4; font-size: .8rem; color: white; text-shadow: 0 1px 2px rgba(0, 0, 0, .6); }
.shutter { width: 76px; height: 76px; border-radius: 50%; border: 5px solid white; background: none; padding: 5px; }
.shutter i { display: block; width: 100%; height: 100%; border-radius: 50%; background: white; transition: border-radius .2s, transform .2s, background .2s; }
.shutter.video i { background: #e03131; }
.shutter.recording i { border-radius: 8px; transform: scale(.55); }
.flip { justify-self: end; width: 52px; height: 52px; border: 0; border-radius: 50%; background: #343a40; font-size: 1.5rem; }
/* the live view: things sit at left/top percentages, so a copy of it scales into the thumbnail */
.cm-o { position: absolute; translate: -50% -50%; line-height: 1; }
.cm-cloud { font-size: 1.1em; }
.cm-bird { font-size: .55em; }
.cm-tree { font-size: 1.15em; }
.cm-house { font-size: 1.05em; }
.cm-fly { font-size: .5em; }
.cm-dog { font-size: .9em; }
.cm-dog.cm-right { scale: -1 1; } /* the emoji faces left */
.cm-balloon { font-size: .4em; }
.cm-ya { font-size: .5em; }
/* a drawn face, so one eye can wink */
.cm-face { position: absolute; translate: -50% -50%; height: 66%; aspect-ratio: .86; border-radius: 48% 48% 46% 46%; background: #ffd5b0; box-shadow: inset 0 -6px 0 rgba(0, 0, 0, .05); }
.cm-face i { position: absolute; display: block; }
.cm-hair { left: -4%; right: -4%; top: -6%; height: 38%; border-radius: 50% 50% 30% 30%; background: #5c3b1e; }
.cm-eye { top: 46%; width: 11%; height: 13%; border-radius: 50%; background: #2b2f36; transition: scale .06s; }
.cm-eye.cm-l { left: 26%; }
.cm-eye.cm-r { right: 26%; }
.cm-eye.cm-shut { scale: 1 .14; }
.cm-cheek { top: 62%; width: 14%; height: 8%; border-radius: 50%; background: #ffa8a8; opacity: .7; }
.cm-cheek.cm-l { left: 13%; }
.cm-cheek.cm-r { right: 13%; }
.cm-mouth { left: 36%; top: 68%; width: 28%; height: 13%; border-radius: 0 0 99px 99px; background: #c92a2a; }

/* the photo: a still copy of the scene */
.cm-pic { position: absolute; left: 0; top: 0; z-index: 3; overflow: hidden; border-radius: 12px; transform-origin: 0 0; background: linear-gradient(#a5d8ff 60%, #8ce99a 60%); pointer-events: none; }
.cm-pic .shot { position: absolute; inset: 0; }
.thumb .cm-pic { border-radius: 0; }
.shutter.cm-quick i { background: #e03131; transform: scale(.8); }
.shutter.cm-quick { border-color: #ffc9c9; }

/* tilt game */
.w-tilt { display: flex; flex-wrap: wrap; justify-content: center; align-items: center; gap: 18px; }
.board { position: relative; width: min(100%, 420px); aspect-ratio: 4 / 3; border-radius: 20px; background: radial-gradient(circle at 30% 30%, #b2f2bb, #69db7c); border: 10px solid #8d6e63; box-shadow: inset 0 4px 12px rgba(0,0,0,.2); touch-action: none; }
.board .hole { position: absolute; width: 52px; height: 52px; translate: -50% -50%; border-radius: 50%; background: radial-gradient(#212529 55%, #495057); }
.board .ball { position: absolute; width: 32px; height: 32px; translate: -50% -50%; border-radius: 50%; background: radial-gradient(circle at 35% 35%, #fff, #adb5bd 60%, #495057); box-shadow: 0 4px 6px rgba(0,0,0,.35); }
.board .score { position: absolute; top: 6px; left: 10px; font-weight: 800; color: #1b4332; }
.tilt-side { display: flex; flex-direction: column; align-items: center; gap: 10px; max-width: 260px; }
.stick { position: relative; width: 160px; height: 160px; border-radius: 50%; background: radial-gradient(#f1f3f5, #ced4da); border: 3px solid var(--line); touch-action: none; }
.stick.off { opacity: .4; }
.knob { position: absolute; left: 50%; top: 50%; width: 64px; height: 64px; margin: -32px 0 0 -32px; border-radius: 50%; background: var(--c); box-shadow: 0 4px 0 color-mix(in srgb, var(--c) 60%, black); }
.tilt-side .readout { margin: 0; font-weight: 800; text-align: center; }
.tilt-side .note { margin: 0; color: var(--ink-2); font-size: .95rem; text-align: center; }

/* orientation */
.w-orient { display: flex; flex-direction: column; align-items: center; gap: 12px; }
.w-orient .real { margin: 0; font-size: 1.1rem; text-align: center; }
.tab-stage { display: grid; place-items: center; width: 280px; height: 280px; }
.tab { width: 150px; height: 210px; padding: 10px; border-radius: 20px; background: #212529; transition: rotate .5s ease-in-out; }
.tab-screen { display: grid; place-items: center; width: 100%; height: 100%; border-radius: 10px; background: #e7f5ff; overflow: hidden; }
.content { display: flex; flex-direction: column; align-items: center; font-size: 3rem; line-height: 1; transition: rotate .4s ease-in-out .35s; }
.content b { font-size: 1.4rem; }
.lockbtn.on, [data-act="lock"].on { border-color: var(--c); background: color-mix(in srgb, var(--c) 10%, white); }
.w-orient .step { margin: 0; font-size: 1.2rem; font-weight: 800; text-align: center; }

/* charging */
.w-charge { display: flex; flex-direction: column; align-items: center; gap: 14px; }
.chargers { display: flex; flex-wrap: wrap; justify-content: center; gap: 10px; }
.rig { display: flex; align-items: center; gap: 0; }
.brick { display: flex; flex-direction: column; align-items: center; padding: 10px 12px; border-radius: 14px; background: white; border: 2px solid var(--line); font-size: 2.4rem; }
.brick small { font-size: .9rem; font-weight: 800; min-height: 1.2em; }
.cable { width: 90px; height: 8px; border-radius: 4px; background: #adb5bd; }
.rig.on .cable { background: repeating-linear-gradient(90deg, var(--c) 0 12px, #ffd43b 12px 20px); animation: flow .5s linear infinite; }
.charge-tab { display: flex; flex-direction: column; align-items: center; justify-content: center; gap: 8px; width: 130px; height: 180px; border-radius: 18px; background: #212529; color: white; }
.batt { position: relative; width: 74px; height: 32px; padding: 3px; border: 3px solid white; border-radius: 7px; }
.batt::after { content: ''; position: absolute; right: -8px; top: 8px; width: 4px; height: 10px; border-radius: 0 2px 2px 0; background: white; }
.batt i { display: block; width: 10%; height: 100%; border-radius: 3px; background: #40c057; }
.batt.slow i { background: #fab005; }
.pct { font-size: 1.3rem; }
.clock { margin: 0; font-family: ui-monospace, Menlo, monospace; font-weight: 800; font-size: 1.1rem; }
.w-charge .readout { margin: 0; text-align: center; font-size: 1.1rem; line-height: 1.7; }

/* find the camera */
.w-findcam { display: flex; flex-direction: column; align-items: center; gap: 10px; }
.devs { display: flex; flex-wrap: wrap; justify-content: center; align-items: flex-end; gap: 22px; }
.dev { margin: 0; display: flex; flex-direction: column; align-items: center; max-width: 240px; }
.dev .body { position: relative; background: #212529; cursor: pointer; }
.dev figcaption { margin-top: 8px; text-align: center; }
.dev figcaption small { display: block; color: var(--good); font-weight: 700; line-height: 1.5; max-width: 220px; }
.dev .lens { position: absolute; width: 7px; height: 7px; translate: -50% -50%; border-radius: 50%; background: #495057; }
.laptop .body { width: 220px; height: 140px; border-radius: 10px 10px 0 0; border: 9px solid #212529; border-top-width: 14px; background: #d0ebff; }
.laptop .lens { left: 50%; top: -7px; }
.laptop .led { position: absolute; left: calc(50% + 10px); top: -9px; width: 4px; height: 4px; border-radius: 50%; background: #2f9e44; box-shadow: 0 0 6px #40c057; }
.laptop .base { width: 250px; height: 12px; border-radius: 0 0 12px 12px; background: #adb5bd; }
.dev.tablet .body { width: 130px; height: 180px; border-radius: 18px; border: 12px solid #212529; background: #ffe3e3; }
.dev.tablet .lens { left: 50%; top: -6px; }
.dev.phone .body { width: 96px; height: 190px; border-radius: 22px; background: #495057; }
.dev.phone .body::before { content: ''; position: absolute; left: 8px; top: 8px; width: 36px; height: 36px; border-radius: 10px; background: #343a40; }
.dev.phone .lens { left: 27%; top: 13%; width: 16px; height: 16px; background: radial-gradient(#4dabf7 20%, #111 30%); }
.dev.phone .body::after { content: ''; position: absolute; left: 32px; top: 30px; width: 8px; height: 8px; border-radius: 50%; background: #fff3bf; }
.dev .ring { position: absolute; width: 40px; height: 40px; translate: -50% -50%; border-radius: 50%; border: 4px solid var(--good); box-shadow: 0 0 0 4px rgba(64,192,87,.3); pointer-events: none; }
.laptop .ring { top: -7px !important; }
.dev.tablet .ring { top: -6px !important; }
.dev .miss { position: absolute; width: 30px; height: 30px; translate: -50% -50%; border-radius: 50%; border: 3px solid var(--bad); pointer-events: none; }

/* URL */
.w-url { display: flex; flex-direction: column; gap: 14px; }
.addr { display: flex; flex-wrap: wrap; align-items: center; gap: 2px; padding: .7rem 1rem; border-radius: 99px; background: white; border: 2px solid var(--line); font-family: ui-monospace, Menlo, monospace; font-size: clamp(1rem, 2.6vw, 1.5rem); }
.addr .lock { margin-right: .4rem; }
.part { min-height: 44px; border: 0; border-radius: 8px; padding: .3rem .2rem; font: inherit; font-weight: 800; background: none; }
.proto { --tone: #d6336c; }
.domain { --tone: #1971c2; }
.path { --tone: #2b8a3e; }
.part { color: var(--tone); box-shadow: inset 0 -4px 0 color-mix(in srgb, var(--tone) 30%, transparent); }
.part.on { background: color-mix(in srgb, var(--tone) 14%, white); }
.explain-box { min-height: 110px; padding: .8rem 1rem; border-radius: var(--radius); background: var(--card); border: 2px solid var(--line); font-size: 1.15rem; line-height: 1.7; }
.explain-box p { margin: 0; }
.explain-box p.proto, .explain-box p.domain, .explain-box p.path { color: var(--tone); font-size: 1.3rem; }
.url-seen { display: flex; flex-wrap: wrap; gap: 8px; }
.url-seen span { padding: .2rem .7rem; border-radius: 99px; border: 2px dashed var(--line); color: var(--ink-3); font-weight: 700; }
.url-seen span.got { border-style: solid; border-color: var(--tone); color: var(--tone); }

/* pass the note */
.w-cipher { position: relative; display: flex; flex-direction: column; align-items: center; gap: 14px; }
.note-msg { margin: 0; font-size: 1.15rem; }
.chain { display: flex; justify-content: space-between; width: 100%; max-width: 640px; gap: 6px; }
.kid { position: relative; display: flex; flex-direction: column; align-items: center; flex: 1; font-size: clamp(2.4rem, 7vw, 3.6rem); }
.kid small { font-size: .9rem; font-weight: 700; color: var(--ink-2); }
.bubble { position: absolute; top: 100%; margin-top: 30px; width: max-content; max-width: 180px; padding: .4rem .6rem; border-radius: 12px; background: #fff9db; border: 2px solid #ffe066; font-size: .95rem; font-weight: 700; line-height: 1.4; text-align: center; }
.peek .bubble { background: #fff5f5; border-color: #ffa8a8; }
.end .bubble { right: 0; }
.w-cipher .controls { margin-top: 90px; }
.w-cipher .step { margin: 0; font-size: 1.15rem; font-weight: 800; text-align: center; }

/* shift cipher */
.w-caesar { display: flex; flex-direction: column; align-items: center; gap: 14px; }
.coded { margin: 0; font-size: 1.3rem; }
.coded b { font-family: ui-monospace, Menlo, monospace; font-size: 2rem; letter-spacing: .15em; color: var(--c); }
.rows { display: flex; flex-direction: column; gap: 4px; }
.row { display: flex; gap: 4px; }
.row i { display: grid; place-items: center; width: clamp(26px, 6vw, 40px); height: clamp(30px, 6vw, 40px); border-radius: 8px; font-style: normal; font-weight: 800; font-family: ui-monospace, Menlo, monospace; }
.row.top i { background: color-mix(in srgb, var(--c) 14%, white); color: var(--c); }
.row.bottom i { background: var(--card); border: 2px solid var(--line); }
.keybar { display: flex; align-items: center; gap: 10px; }
.keybar label { display: flex; flex-direction: column; align-items: center; gap: 4px; font-weight: 800; }
.keybar input { width: min(260px, 50vw); height: 44px; accent-color: var(--c); }
.keybar .option { min-width: 56px; font-size: 1.4rem; text-align: center; }
.decoded { margin: 0; font-size: 1.3rem; }
.decoded b { font-family: ui-monospace, Menlo, monospace; font-size: 2rem; letter-spacing: .15em; }
.decoded.ok b { color: var(--good); }

/* update */
.w-update { display: flex; flex-direction: column; align-items: center; gap: 12px; }
.w-update .step { margin: 0; font-size: 1.15rem; font-weight: 800; text-align: center; min-height: 1.7em; }
.app { width: min(100%, 380px); border-radius: 18px; overflow: hidden; background: white; border: 3px solid var(--line); }
.app.crash { filter: grayscale(1) brightness(.7); }
.app-head { display: flex; justify-content: space-between; padding: .5rem .9rem; background: color-mix(in srgb, var(--c) 12%, white); }
.ver { font-family: ui-monospace, Menlo, monospace; font-weight: 800; color: var(--c); }
.app-canvas { position: relative; display: grid; place-items: center; height: 130px; font-size: 3rem; }
.leak { position: absolute; right: 10px; bottom: 6px; font-size: 1.8rem; }
.leak i { font-style: normal; font-size: 1.4rem; margin-left: -6px; }
.leak.fixed { font-size: 1.6rem; }
.leak.fixed::after { content: '🛡️'; position: absolute; left: 0; top: 0; }
.leak.fixed i { opacity: 0; }
.app-tools { display: flex; flex-wrap: wrap; justify-content: center; gap: 8px; padding: .6rem; border-top: 1px solid var(--line); }
.app-tools button { min-height: 48px; padding: .4rem .9rem; border: 2px solid var(--line); border-radius: 12px; background: white; font-weight: 800; }
.upd { display: flex; flex-direction: column; align-items: center; gap: 8px; }
.upd .progress { position: relative; width: 260px; height: 28px; border-radius: 14px; background: var(--line); overflow: hidden; }
.upd .progress i { display: block; height: 100%; width: 0; background: var(--c); }
.upd .progress span { position: absolute; inset: 0; display: grid; place-items: center; font-weight: 800; font-size: .9rem; }
.notes { margin: 0; padding: .6rem 1rem .6rem 1.4rem; border-radius: 14px; background: #fff9db; line-height: 1.8; font-weight: 700; }

@media (orientation: portrait) and (min-width: 700px) and (min-height: 900px) {
  .playground .cell { min-height: 150px; }
  .obj { font-size: 3.8rem; }
  .tasks li { font-size: 1.15rem; }
  .board { width: min(100%, 560px); }
  .tab-stage { width: 340px; height: 340px; }
  .tab { width: 180px; height: 250px; }
}

.part-desc { margin: .2rem 0 0; color: var(--ink-3); }
.part-desc + .units { margin-top: .8rem; }

/* ---------- screen: LCD vs OLED ---------- */

.w-screen { display: flex; flex-direction: column; gap: 14px; }
.tabs { display: flex; justify-content: center; gap: 10px; }
.tabs .on, .opts .on, .names .on { border-color: var(--c); background: color-mix(in srgb, var(--c) 12%, white); }
.split { display: flex; flex-wrap: wrap; justify-content: center; align-items: center; gap: 20px; }
.layers { display: flex; flex-direction: column; gap: 6px; width: min(100%, 300px); min-height: 200px; justify-content: center; }
.ly { position: relative; display: flex; align-items: center; justify-content: center; gap: 6px; min-height: 44px; padding: 4px 8px; border-radius: 10px; font-weight: 800; font-size: .95rem; }
.ly span { margin-left: 6px; }
.ly.eye { background: none; }
.ly.filter, .ly.emit { background: #343a40; color: white; }
.ly i { display: block; width: 26px; height: 26px; border-radius: 6px; }
.ly .r { background: #fa5252; } .ly .g { background: #40c057; } .ly .b { background: #4c6ef5; }
.ly.emit i { box-shadow: 0 0 12px currentColor; }
.ly.emit .r { color: #fa5252; } .ly.emit .g { color: #40c057; } .ly.emit .b { color: #4c6ef5; }
.ly.blinds { background: #dee2e6; }
.ly.blinds i { width: 26px; height: 26px; border-radius: 3px; background: repeating-linear-gradient(0deg, #868e96 0 3px, transparent 3px 7px); }
.ly.back { background: #fff9db; box-shadow: 0 0 18px #ffe066; }
.layers.black .ly.blinds i { background: #495057; }
.layers.black .ly.filter i, .layers.black .ly.emit i { opacity: .15; box-shadow: none; }
.layers.black .ly.back { box-shadow: 0 0 18px #ffe066; }
.demo { display: flex; flex-direction: column; align-items: center; gap: 10px; }
.mini { position: relative; display: grid; place-items: center; width: 200px; height: 140px; border: 10px solid #111; border-radius: 14px; background: linear-gradient(#1c2a5a, #3b5bdb); font-size: 3rem; }
.mini .stars { position: absolute; top: 10px; right: 16px; font-size: 1.2rem; }
.mini.black { background: #000; }
.mini.black > span { visibility: hidden; }
.w-screen[data-mode="lcd"] .mini.black { background: #23252b; box-shadow: inset 0 0 30px rgba(255,255,255,.08); }
.w-screen .say { margin: 0; font-size: 1.15rem; font-weight: 700; text-align: center; line-height: 1.6; }

/* ---------- waves ---------- */

.w-waves { display: flex; flex-direction: column; gap: 10px; }
.wave { width: 100%; height: 110px; }
.wave path { fill: none; stroke: var(--c); stroke-width: 4; vector-effect: non-scaling-stroke; transition: d .3s; }
.wave[data-zone="3"] path { stroke: url(#none); stroke: #e64980; }
.band { display: grid; grid-template-columns: repeat(6, 1fr); border-radius: 14px; overflow: hidden; border: 2px solid var(--line); }
.zone { display: flex; flex-direction: column; align-items: center; gap: 2px; padding: .5rem .2rem; border: 0; font-weight: 800; }
.zone span { font-size: 1.8rem; }
.zone small { font-size: .85rem; }
.z0 { background: #e9ecef; } .z1 { background: #dee2e6; } .z2 { background: #ffe3e3; }
.z3 { background: linear-gradient(90deg, #ffc9c9, #ffec99, #b2f2bb, #a5d8ff, #d0bfff); }
.z4 { background: #e5dbff; } .z5 { background: #d0bfff; }
.zone.on { outline: 4px solid var(--c); outline-offset: -4px; }
.zone.got::after { content: '✓'; color: var(--good); font-weight: 900; }
.axis { display: flex; justify-content: space-between; color: var(--ink-3); font-weight: 700; font-size: .9rem; }

/* ---------- wireless charging ---------- */

.w-qi { display: flex; flex-direction: column; align-items: center; gap: 12px; }
.desk2 { position: relative; width: min(100%, 520px); height: 240px; border-radius: 18px; background: repeating-linear-gradient(90deg, #c8a27a 0 40px, #c39b71 40px 80px); touch-action: none; }
.qpad { position: absolute; left: 62%; top: 50%; width: 130px; height: 130px; translate: -50% -50%; border-radius: 50%; background: #343a40; display: grid; place-items: center; }
.qpad i { position: absolute; border-radius: 50%; border: 3px solid #fab005; opacity: .5; }
.qpad i:nth-child(1) { inset: 22px; } .qpad i:nth-child(2) { inset: 34px; } .qpad i:nth-child(3) { inset: 46px; }
.qpad.on i { opacity: 1; box-shadow: 0 0 10px #fab005; animation: wave 1s infinite; }
.qphone { position: absolute; width: 84px; height: 160px; translate: -50% -50%; border-radius: 18px; background: rgba(33,37,41,.88); border: 3px solid #212529; cursor: grab; touch-action: none; display: grid; place-items: center; }
.qcoil { position: relative; width: 60px; height: 60px; }
.qcoil i { position: absolute; border-radius: 50%; border: 2px dashed #adb5bd; }
.qcoil i:nth-child(1) { inset: 4px; } .qcoil i:nth-child(2) { inset: 16px; }
.qphone.charging .qcoil i { border-color: #fab005; border-style: solid; }
.bolt { position: absolute; top: 6px; font-size: 1.4rem; }
.qbatt { display: flex; align-items: center; gap: 10px; padding: 8px 14px; border-radius: 14px; background: #212529; color: white; }
.w-qi .readout { margin: 0; font-weight: 800; font-size: 1.1rem; text-align: center; }

/* ---------- coding robot ---------- */

.w-code { display: flex; flex-wrap: wrap; justify-content: center; align-items: flex-start; gap: 18px; }
.cgrid { position: relative; display: grid; grid-template-columns: repeat(var(--cols), 1fr); gap: 4px; width: min(100%, 360px); padding: 6px; border-radius: 14px; background: #d3f9d8; }
.cgrid i { display: grid; place-items: center; aspect-ratio: 1; border-radius: 8px; background: white; font-style: normal; font-size: 1.8rem; }
.cgrid i.rock { background: #e9ecef; }
.bot { position: absolute; translate: -50% -50%; font-size: 2.2rem; transition: left .3s, top .3s; pointer-events: none; }
.cside { display: flex; flex-direction: column; gap: 10px; width: min(100%, 320px); }
.prog { display: flex; flex-wrap: wrap; gap: 6px; min-height: 64px; padding: 8px; border-radius: 14px; background: var(--card); border: 2px dashed var(--line); }
.prog .empty { color: var(--ink-3); font-size: .95rem; align-self: center; }
.step-chip { display: grid; place-items: center; width: 40px; height: 40px; border-radius: 10px; background: var(--paper); font-size: 1.4rem; }
.step-chip.on { background: var(--c); box-shadow: 0 0 0 3px color-mix(in srgb, var(--c) 30%, transparent); }
.cmds { display: flex; flex-wrap: wrap; gap: 8px; }
.cmds [data-cmd] { font-size: 1.6rem; min-width: 64px; text-align: center; }
.w-code .readout { margin: 0; font-weight: 800; }

/* ---------- drop test ---------- */

.w-drop { display: flex; flex-direction: column; align-items: center; gap: 12px; }
.opts { display: flex; gap: 10px; }
.drop-stage { position: relative; width: min(100%, 420px); height: 260px; --fall: 150px; }
.table { position: absolute; left: 0; top: 70px; width: 45%; height: 14px; border-radius: 4px; background: #8d6e63; }
.floor { position: absolute; left: 0; right: 0; bottom: 0; height: 18px; border-radius: 4px; background: #adb5bd; }
.dphone { position: absolute; left: 22%; top: 6px; width: 40px; height: 64px; padding: 4px; border-radius: 8px; background: #212529; transform-origin: center; }
.dscreen { position: relative; width: 100%; height: 100%; border-radius: 4px; background: #a5d8ff; }
.dphone.has-case { outline: 5px solid #f08c00; }
.dphone.has-film .dscreen { box-shadow: inset 0 0 0 3px rgba(255,255,255,.8); }
.dphone.crack-screen .dscreen::after, .dphone.crack-film .dscreen::after { content: ''; position: absolute; inset: 0; background: linear-gradient(35deg, transparent 45%, #212529 46%, transparent 48%), linear-gradient(-50deg, transparent 52%, #212529 53%, transparent 55%), linear-gradient(80deg, transparent 30%, #212529 31%, transparent 33%); }
.dphone.crack-film .dscreen::after { opacity: .35; }
.dphone.dent { border-radius: 8px 2px 8px 8px; box-shadow: 4px -4px 0 -2px #fa5252; }
.w-drop .result { margin: 0; font-size: 1.15rem; font-weight: 800; text-align: center; line-height: 1.6; }
/* the close-up that swaps a cracked screen protector */
.dr-zoom { position: absolute; right: 0; top: 0; z-index: 2; display: flex; flex-direction: column; align-items: center; gap: 6px; width: 46%; padding: 8px 6px 10px; border-radius: 16px; background: var(--card); border: 2px solid var(--line); box-shadow: var(--shadow); }
.dr-say { margin: 0; min-height: 2.6em; font-weight: 800; font-size: .95rem; line-height: 1.3; text-align: center; }
.dr-phone { position: relative; width: 96px; height: 160px; padding: 7px; border-radius: 16px; background: #212529; overflow: hidden; }
.dr-screen { display: grid; place-items: center; width: 100%; height: 100%; border-radius: 9px; background: #a5d8ff; }
.dr-ok { font-size: 2.2rem; opacity: 0; }
.dr-film, .dr-new { position: absolute; inset: 5px; border-radius: 11px; border: 2px solid rgba(255, 255, 255, .9); background: rgba(255, 255, 255, .28); }
.dr-film { background:
  linear-gradient(35deg, transparent 45%, rgba(33, 37, 41, .8) 46%, transparent 48%),
  linear-gradient(-50deg, transparent 52%, rgba(33, 37, 41, .8) 53%, transparent 55%),
  linear-gradient(80deg, transparent 30%, rgba(33, 37, 41, .8) 31%, transparent 33%),
  rgba(255, 255, 255, .28); }
.dr-new { opacity: 0; }

/* ---------- files ---------- */

/* files go into a folder */
.w-stash { position: relative; display: flex; flex-direction: column; align-items: center; gap: 10px; }
.sh-files { display: flex; flex-wrap: wrap; justify-content: center; gap: 12px; }
.sh-file { display: flex; flex-direction: column; align-items: center; gap: 2px; min-width: 88px; padding: 10px 8px; border: 2px solid var(--line); border-radius: 16px; background: var(--card); font-weight: 800; box-shadow: var(--shadow); }
.sh-file b, .sh-fly b { font-size: 2.6rem; line-height: 1.1; }
.sh-file.sh-gone { visibility: hidden; }
.sh-fly { position: absolute; z-index: 3; margin: 0; pointer-events: none; }
.sh-arrow { color: var(--ink-3); font-size: 1.6rem; }
.sh-folder { display: flex; flex-direction: column; align-items: center; gap: 2px; min-width: 180px; padding: 10px 18px; border: 2px dashed var(--c); border-radius: 20px; background: color-mix(in srgb, var(--c) 6%, white); font-weight: 800; }
.sh-folder b { font-size: 4.4rem; line-height: 1.1; }
.sh-count { color: var(--ink-2); font-style: normal; font-size: .95rem; }
.sh-inside { display: flex; flex-wrap: wrap; justify-content: center; gap: 6px; margin: 0; padding: 0; list-style: none; }
.sh-inside li { padding: 4px 10px; border-radius: 10px; background: var(--card); border: 2px solid var(--line); font-weight: 800; }
.sh-hint { margin: 0; font-weight: 800; color: var(--ink-2); text-align: center; }


.fm { position: relative; display: grid; grid-template-columns: 150px 1fr; min-height: 300px; border-radius: var(--radius); overflow: hidden; background: var(--card); border: 2px solid var(--line); }
.fm-side { display: flex; flex-direction: column; gap: 4px; padding: 8px; background: var(--paper); }
.fm-side button { min-height: 48px; padding: .4rem .6rem; border: 0; border-radius: 10px; background: none; text-align: left; font-weight: 800; }
.fm-side button.on { background: color-mix(in srgb, var(--c) 15%, white); }
.fm-side b { color: var(--ink-3); }
.fm-main { display: flex; flex-direction: column; gap: 10px; padding: 10px; }
.fm-title { margin: 0; font-weight: 800; }
.fm-items { display: flex; flex-wrap: wrap; gap: 8px; min-height: 110px; align-content: flex-start; }
.file { display: flex; flex-direction: column; align-items: center; width: 96px; padding: 6px 4px; border: 2px solid transparent; border-radius: 12px; background: none; }
.file span { font-size: 2.6rem; }
.file small { font-weight: 700; font-size: .85rem; word-break: break-all; }
.file.sel { border-color: var(--c); background: color-mix(in srgb, var(--c) 10%, white); }
.fm .empty { margin: 0; color: var(--ink-3); }
.fm-actions { display: flex; flex-wrap: wrap; gap: 8px; align-items: center; margin-top: auto; padding-top: 8px; border-top: 1px solid var(--line); }
.fm-actions .option { font-size: 1rem; min-height: 48px; padding: .4rem .8rem; }
.option.danger { border-color: #ffc9c9; color: var(--bad); }
.rename { min-height: 48px; padding: .3rem .6rem; border: 2px solid var(--c); border-radius: 10px; font: inherit; font-size: 16px; width: 10em; }
.dialog { position: absolute; inset: 0; z-index: 7; display: grid; place-items: center; align-content: center; gap: 10px; padding: 16px; background: rgba(255,255,255,.94); text-align: center; }
.dialog p { margin: 0; font-size: 1.15rem; line-height: 1.6; }
.dialog div { display: flex; gap: 10px; justify-content: center; }
.dialog .danger { background: var(--bad); color: white; border-color: var(--bad); }
@media (max-width: 560px) { .fm { grid-template-columns: 1fr; } .fm-side { flex-direction: row; flex-wrap: wrap; } }

/* ---------- passcode ---------- */

.lockwrap { display: flex; flex-direction: column; align-items: center; gap: 10px; }
.lockphone { position: relative; width: 250px; min-height: 400px; padding: 16px; border-radius: 34px; background: linear-gradient(#364fc7, #9c36b5); color: white; border: 8px solid #111; overflow: hidden; }
.lock-top { display: flex; flex-direction: column; align-items: center; gap: 2px; }
.lock-top b { font-size: 2.2rem; font-weight: 300; }
.lock-msg { margin: 8px 0; text-align: center; font-weight: 700; min-height: 2.6em; font-size: .95rem; }
.pdots { display: flex; justify-content: center; gap: 12px; margin-bottom: 12px; }
.pdots i { width: 14px; height: 14px; border-radius: 50%; border: 2px solid white; }
.pdots i.on { background: white; }
.keypad { display: grid; grid-template-columns: repeat(3, 1fr); gap: 10px; justify-items: center; }
.keypad button { width: 58px; height: 58px; border-radius: 50%; border: 0; background: rgba(255,255,255,.22); color: white; font-size: 1.5rem; }
.keypad button:active { background: rgba(255,255,255,.5); }
.unlocked { display: flex; flex-direction: column; align-items: center; gap: 18px; margin-top: 20px; }
.unlocked .apps { display: grid; grid-template-columns: repeat(4, 1fr); gap: 14px; font-size: 2rem; }
.unlocked .option { color: var(--ink); }
.scan { position: absolute; inset: 0; display: grid; place-items: center; background: rgba(0,0,0,.6); font-size: 4rem; }
.scan span { padding: 12px; border-radius: 24px; border: 3px dashed #69db7c; animation: wave .5s infinite; }
.lockwrap .hint { margin: 0; }

/* ---------- account ---------- */

.w-account { display: flex; justify-content: center; }
.acc-warn { margin: 6px 0 0; padding: 8px 12px; border-radius: 12px; background: #fff4e6; border: 2px solid #ffa94d; color: #a63e00; font-weight: 700; line-height: 1.5; }
.acc-tip { margin: 6px 0 0; color: var(--ink-3); font-size: .9rem; font-weight: 700; }
.form { display: flex; flex-direction: column; gap: 8px; width: min(100%, 460px); padding: 16px; border-radius: var(--radius); background: var(--card); border: 2px solid var(--line); }
.form-title { margin: 0; font-size: 1.3rem; font-weight: 900; }
.lbl { margin: .4rem 0 0; font-weight: 800; display: flex; align-items: center; gap: .3rem; }
.eye-btn { border: 0; background: none; font-size: 1.2rem; min-width: 44px; min-height: 44px; }
.names, .tiles { display: flex; flex-wrap: wrap; gap: 8px; }
.names .option, .tiles .option { min-height: 48px; padding: .3rem .9rem; font-size: 1.05rem; }
.tiles .option { min-width: 52px; font-family: ui-monospace, Menlo, monospace; }
.pw { display: flex; gap: 8px; align-items: center; }
.pw-text { flex: 1; min-height: 48px; display: flex; align-items: center; padding: 0 .8rem; border-radius: 12px; background: var(--paper); font-family: ui-monospace, Menlo, monospace; font-size: 1.2rem; letter-spacing: .05em; overflow-wrap: anywhere; }
.meter { position: relative; height: 26px; border-radius: 13px; background: var(--line); overflow: hidden; }
.meter i { display: block; height: 100%; width: 0; background: var(--bad); transition: width .2s; }
.meter[data-k="2"] i, .meter[data-k="3"] i { background: #fab005; }
.meter[data-k="4"] i, .meter[data-k="5"] i { background: var(--good); }
.meter span { position: absolute; inset: 0; display: grid; place-items: center; font-weight: 800; font-size: .9rem; }
.form .go { align-self: flex-start; margin-top: 6px; }
.form .msg { margin: 0; font-weight: 700; line-height: 1.6; min-height: 1.6em; }

/* ---------- network speed ---------- */

.w-speed { display: flex; flex-direction: column; align-items: center; gap: 14px; }
.speeds { display: flex; flex-wrap: wrap; justify-content: center; gap: 10px; }
.speeds .option { display: flex; flex-direction: column; align-items: center; min-width: 150px; }
.speeds small { font-weight: 600; color: var(--ink-2); font-size: .85rem; }
.dl-card { display: flex; align-items: center; gap: 12px; width: min(100%, 460px); padding: 12px 16px; border-radius: var(--radius); background: var(--card); border: 2px solid var(--line); }
.dl-icon { font-size: 2.6rem; }
.dl-body { flex: 1; display: flex; flex-direction: column; gap: 6px; }
.dl-bar { height: 16px; border-radius: 8px; background: var(--line); overflow: hidden; }
.dl-bar i { display: block; height: 100%; width: 0; background: var(--c); }
.dl-text { color: var(--ink-2); font-weight: 700; }
.w-speed .readout { margin: 0; text-align: center; font-size: 1.1rem; font-weight: 700; line-height: 1.7; }

/* ---------- select ---------- */

.selbox { display: flex; flex-direction: column; gap: 10px; }
.mods { display: flex; flex-wrap: wrap; gap: 8px; }
.mods .option { font-size: 1rem; min-height: 48px; padding: .4rem .9rem; }
.mods .on { border-color: var(--c); background: color-mix(in srgb, var(--c) 14%, white); }
.tiles-grid { display: grid; grid-template-columns: repeat(4, 1fr); gap: 10px; padding: 12px; border-radius: var(--radius); background: var(--card); border: 2px solid var(--line); }
.tile { position: relative; aspect-ratio: 1; border: 3px solid transparent; border-radius: 14px; background: var(--paper); font-size: clamp(2rem, 6vw, 3rem); }
.tile i { position: absolute; right: 6px; bottom: 6px; width: 24px; height: 24px; border-radius: 50%; border: 2px solid #ced4da; background: white; }
.tile.on { border-color: var(--c); background: color-mix(in srgb, var(--c) 10%, white); }
.tile.on i { background: var(--c); border-color: var(--c); }
.tile.on i::after { content: '✓'; display: block; color: white; font-size: 14px; line-height: 20px; text-align: center; font-style: normal; }
.selcount { margin: 0; font-weight: 800; }

/* ---------- folders ---------- */

.fold-box { position: relative; display: flex; flex-direction: column; gap: 10px; padding: 12px; border-radius: var(--radius); background: var(--card); border: 2px solid var(--line); }
.crumbs { display: flex; align-items: center; gap: .3rem; padding: .4rem .7rem; border-radius: 10px; background: var(--paper); font-weight: 700; }
.crumbs button { border: 0; background: none; font-weight: 800; color: var(--c); padding: .2rem .4rem; min-height: 44px; }
.fold-tools { display: flex; flex-wrap: wrap; align-items: center; gap: 8px; }
.fold-tools .option { font-size: 1rem; min-height: 48px; padding: .3rem .8rem; }
.name-pick { display: inline-flex; flex-wrap: wrap; align-items: center; gap: 6px; font-weight: 700; }
.fold-area { display: flex; flex-wrap: wrap; align-items: flex-start; gap: 10px; min-height: 120px; }
.fold { display: flex; flex-direction: column; align-items: center; width: 100px; padding: 8px 4px; border: 3px dashed transparent; border-radius: 14px; background: #fff9db; font-weight: 800; }
.fold span { font-size: 2.6rem; }
.fold small { color: var(--ink-3); font-weight: 600; }
.fold.over { border-color: var(--c); }
.file-chip { display: flex; align-items: center; gap: .4rem; padding: .4rem .8rem; border-radius: 12px; background: var(--paper); font-weight: 700; }
.file-chip span { font-size: 1.6rem; }
.fold-area .up { font-size: 1rem; min-height: 48px; padding: .3rem .8rem; }
.fold-area .empty { color: var(--ink-3); margin: 0; align-self: center; }
.tree { font-size: .95rem; color: var(--ink-2); }
.tree p { margin: 0 0 4px; font-weight: 800; }
.tree ul { margin: 0; padding-left: 1.2rem; list-style: none; border-left: 2px solid var(--line); }
.tree > ul { border-left: 0; padding-left: 0; }
.tree li { padding: 1px 0 1px .3rem; }

/* ---------- clipboard ---------- */

.clip-box { display: flex; flex-direction: column; gap: 10px; }
.cnote { padding: 10px 12px; border-radius: var(--radius); background: #fffdf0; border: 2px solid #ffe8a1; }
.note-title { margin: 0 0 6px; font-weight: 800; }
.wordrow { display: flex; flex-wrap: wrap; gap: 6px; min-height: 48px; align-items: center; }
.wd { min-height: 44px; padding: .3rem .7rem; border: 2px solid transparent; border-radius: 8px; background: white; font-size: 1.25rem; font-weight: 700; }
button.wd.on { background: #a5d8ff; border-color: #4dabf7; }
.wordrow .empty { color: var(--ink-3); }
.clip-bar { display: flex; flex-wrap: wrap; gap: 8px; }
.clip-bar .option { font-size: 1rem; min-height: 48px; padding: .3rem .8rem; }
.clip { margin: 0; padding: .5rem .8rem; border-radius: 12px; background: var(--paper); font-weight: 700; }

/* ---------- battery ---------- */

.bat-box { display: flex; flex-direction: column; gap: 8px; padding: 12px; border-radius: var(--radius); background: var(--card); border: 2px solid var(--line); }
.bat-row { display: flex; flex-wrap: wrap; align-items: center; justify-content: space-between; gap: 8px; padding: 4px 0; border-bottom: 1px solid var(--line); }
.bat-lbl { font-weight: 800; }
.seg { display: inline-flex; border-radius: 12px; overflow: hidden; border: 2px solid var(--line); }
.seg button { min-height: 44px; min-width: 64px; padding: .2rem .7rem; border: 0; background: white; font-weight: 700; }
.seg button + button { border-left: 2px solid var(--line); }
.seg button.on { background: var(--c); color: white; }
.bat-out { display: flex; flex-direction: column; gap: 6px; margin-top: 6px; }
.drain { height: 22px; border-radius: 11px; background: var(--line); overflow: hidden; }
.drain i { display: block; height: 100%; width: 0; transition: width .25s, background .25s; background: var(--good); }
.drain[data-level="mid"] i { background: #fab005; }
.drain[data-level="high"] i { background: var(--bad); }
.hours { margin: 0; font-size: 1.15rem; }
.hours b { font-size: 1.5rem; color: var(--c); }

/* ---------- GPS ---------- */

.w-gps { display: flex; flex-direction: column; align-items: center; gap: 10px; }
.sky2 { position: relative; width: min(100%, 520px); aspect-ratio: 400 / 260; border-radius: 18px; background: linear-gradient(#1c2a5a, #364fc7 70%, #69db7c 70%); overflow: hidden; }
.sky2 svg { position: absolute; inset: 0; width: 100%; height: 100%; }
.orbit { fill: none; stroke: #ffd43b; stroke-width: 2.5; stroke-dasharray: 6 5; opacity: 0; transition: opacity .3s; }
.orbit.show { opacity: .9; }
.orbit.r1 { stroke: #ff8787; } .orbit.r2 { stroke: #8ce99a; }
.sat { position: absolute; translate: -50% -50%; width: 56px; height: 56px; border: 0; border-radius: 50%; background: rgba(255,255,255,.15); font-size: 1.9rem; }
.sat.on { background: rgba(255,212,59,.45); }
.gps-me { position: absolute; translate: -50% -100%; font-size: 2rem; }
.w-gps .readout { margin: 0; font-weight: 800; font-size: 1.1rem; text-align: center; }
/* GPS: once located, the sky fades into a map */
.gps-map { opacity: 0; transition: opacity .8s ease; }
.sky2.located .gps-map { opacity: 1; }
.sky2.located .orbit.show { opacity: .5; }
.sky2.located .sat { background: rgba(28, 126, 214, .18); opacity: .6; transition: opacity .8s; }
.gps-acc { fill: rgba(28, 126, 214, .18); stroke: rgba(28, 126, 214, .5); stroke-width: 1.5; }
.sky2.located .gps-acc { animation: gps-pulse 1.8s ease-out infinite; transform-box: fill-box; transform-origin: center; }
@keyframes gps-pulse { 0% { transform: scale(.6); opacity: 1; } 100% { transform: scale(1.4); opacity: 0; } }
.sky2.located .gps-me { filter: drop-shadow(0 2px 2px rgba(0, 0, 0, .3)); }

/* ---------- control center ---------- */

.cc-box { display: flex; flex-wrap: wrap; gap: 16px; align-items: flex-start; justify-content: center; }
.cc { display: grid; grid-template-columns: repeat(2, 96px); gap: 12px; padding: 14px; border-radius: 28px; background: #343a40; }
.cc-tile { display: flex; flex-direction: column; align-items: center; justify-content: center; gap: 4px; height: 96px; border: 0; border-radius: 22px; background: #495057; color: white; font-weight: 700; }
.cc-tile span { font-size: 2rem; filter: grayscale(1); opacity: .6; }
.cc-tile.on { background: var(--c); }
.cc-tile.on span { filter: none; opacity: 1; }
.cc-tile[data-k="air"].on { background: #f08c00; }
.cc-tile:disabled { opacity: .45; }
.can { list-style: none; margin: 0; padding: 12px; display: flex; flex-direction: column; gap: 6px; min-width: 220px; max-width: 300px; border-radius: var(--radius); background: var(--card); border: 2px solid var(--line); font-weight: 700; line-height: 1.4; }
.can .no { color: var(--ink-3); text-decoration: line-through; }
.can .ok { color: var(--ink); }

/* ---------- personal hotspot ---------- */

.w-hot { display: flex; flex-direction: column; align-items: center; gap: 12px; }
.w-hot .step { margin: 0; font-size: 1.15rem; font-weight: 800; text-align: center; }
.hot-row { display: flex; align-items: center; justify-content: center; gap: 8px; width: 100%; }
.hdev { display: flex; flex-direction: column; align-items: center; gap: 6px; flex: 1; max-width: 230px; padding: 12px; border-radius: 22px; background: var(--card); border: 2px solid var(--line); text-align: center; }
.hicon { font-size: 2.8rem; }
.hdev small { color: var(--ink-2); font-weight: 600; }
.hdev .option { font-size: 1rem; min-height: 48px; padding: .3rem .7rem; }
.hdev .option.on { border-color: var(--good); background: #ebfbee; }
.nets, .pwpick { display: flex; flex-direction: column; gap: 6px; width: 100%; }
.beam { flex: 0 0 60px; height: 8px; border-radius: 4px; background: repeating-linear-gradient(90deg, var(--line) 0 8px, transparent 8px 14px); }
.w-hot.sharing .beam { background: repeating-linear-gradient(90deg, #ffc078 0 8px, transparent 8px 14px); }
.w-hot.linked .beam { background: repeating-linear-gradient(90deg, var(--c) 0 8px, transparent 8px 14px); animation: flow .6s linear infinite; }
.w-hot .usage { margin: 0; font-weight: 700; text-align: center; min-height: 1.6em; }
/* the phone's battery: a bar and a percentage */
.hbat { display: flex; align-items: center; flex-wrap: wrap; justify-content: center; gap: 6px; font-weight: 800; }
.hbat-cell { position: relative; margin-right: 6px; width: 44px; height: 20px; padding: 2px; border: 2px solid var(--ink-2); border-radius: 5px; }
.hbat-cell::after { content: ''; position: absolute; right: -6px; top: 5px; width: 3px; height: 6px; border-radius: 0 2px 2px 0; background: var(--ink-2); }
.hbat-cell i { display: block; height: 100%; border-radius: 2px; background: #40c057; transition: width .3s, background .3s; }
.hbat-fast { color: #e8590c; font-style: normal; font-size: .9rem; }
.hbat.fast .hbat-cell { border-color: #e8590c; }

/* ---------- book index panel ---------- */

.ix-open {
  position: absolute;
  top: max(.5rem, env(safe-area-inset-top));
  right: max(.5rem, env(safe-area-inset-right));
  min-height: 48px; padding: .4rem 1rem;
  border: 2px solid var(--line); border-radius: 99px;
  background: var(--card); font-weight: 800;
  box-shadow: 0 2px 0 var(--line);
}
#book-index { position: fixed; inset: 0; z-index: 50; }
.ix-veil { position: absolute; inset: 0; background: rgba(29, 39, 56, .35); opacity: 0; transition: opacity .2s; }
.ix {
  position: absolute; top: 0; right: 0; bottom: 0;
  width: min(440px, 92vw);
  display: flex; flex-direction: column;
  background: var(--paper);
  box-shadow: -8px 0 30px rgba(0, 0, 0, .18);
  transform: translateX(100%);
  transition: transform .22s ease-out;
  padding-bottom: env(safe-area-inset-bottom);
}
#book-index.open .ix { transform: none; }
#book-index.open .ix-veil { opacity: 1; }
@media (prefers-reduced-motion: reduce) { .ix, .ix-veil { transition: none; } }
.ix-head { display: flex; align-items: center; justify-content: space-between; gap: 8px; padding: max(.6rem, env(safe-area-inset-top)) .8rem .6rem; background: var(--card); border-bottom: 1px solid var(--line); }
.ix-tabs { display: flex; gap: 6px; }
.ix-tabs button { min-height: 44px; padding: .3rem .9rem; border: 2px solid var(--line); border-radius: 99px; background: var(--card); font-weight: 800; }
.ix-tabs button[aria-selected="true"] { background: var(--ink); border-color: var(--ink); color: white; }
.ix-body { flex: 1; overflow-y: auto; -webkit-overflow-scrolling: touch; padding: .4rem .9rem 1.4rem; overscroll-behavior: contain; }
.ix-part { margin: 1rem 0 .4rem; font-size: 1.05rem; color: var(--ink-2); }
.ix-unit { margin: 0 0 6px; border-radius: 12px; background: var(--card); border-left: 6px solid var(--c); }
.ix-unit summary { display: flex; flex-wrap: wrap; align-items: baseline; gap: .35rem; padding: .6rem .7rem; font-weight: 800; cursor: pointer; list-style: none; }
.ix-unit summary::-webkit-details-marker { display: none; }
.ix-unit summary::after { content: '▸'; margin-left: auto; color: var(--ink-3); }
.ix-unit[open] summary::after { content: '▾'; }
.ix-unit summary small { width: 100%; padding-left: 2rem; color: var(--c); font-size: .8rem; }
.ix-no { display: inline-grid; place-items: center; width: 1.6rem; height: 1.6rem; border-radius: 50%; background: var(--c); color: white; font-size: .85rem; }
.ix-unit ol { margin: 0; padding: 0 .7rem .7rem 2.4rem; }
.ix-unit li { padding: .25rem 0; line-height: 1.45; }
.ix-unit li a { font-weight: 700; text-decoration: none; }
.ix-unit li a:active { color: var(--c); }
.ix-unit li.cur { background: color-mix(in srgb, var(--c) 12%, white); margin-left: -.5rem; padding-left: .5rem; border-radius: 6px; }
.ix-terms { display: block; color: var(--ink-3); font-size: .85rem; }
.ix-soon { color: var(--ink-3); font-weight: 700; margin: .6rem 0 0; }
.ix-search { width: 100%; min-height: 48px; margin-top: .6rem; padding: .4rem .8rem; border: 2px solid var(--line); border-radius: 12px; font: inherit; font-size: 16px; background: white; }
.ix-count { margin: .4rem 0; color: var(--ink-3); font-size: .9rem; }
.ix-list { list-style: none; margin: 0; padding: 0; display: flex; flex-direction: column; gap: 4px; }
.ix-list a { display: flex; flex-wrap: wrap; align-items: baseline; gap: .2rem .4rem; padding: .45rem .6rem; border-radius: 10px; background: var(--card); text-decoration: none; }
.ix-list small { width: 100%; color: var(--ink-3); font-size: .8rem; }
.ix-list .en { --c: #495057; }

/* a primary button inside a .controls row keeps its accent color */
.controls .go { background: var(--c); border-color: var(--c); color: white; box-shadow: 0 3px 0 color-mix(in srgb, var(--c) 70%, black); }
.bubble { max-width: 150px; }

/* ---------- saved progress ---------- */

.total-stars { margin: .6rem 0 0; color: var(--star); font-weight: 900; font-size: 1.15rem; }
.resume {
  display: inline-flex; align-items: center; margin-top: .6rem;
  min-height: 52px; padding: .5rem 1.2rem;
  border-radius: 99px; background: var(--c); color: white;
  font-weight: 800; text-decoration: none;
  box-shadow: 0 3px 0 color-mix(in srgb, var(--c) 70%, black);
}
.resume:active { transform: translateY(2px); box-shadow: 0 1px 0 color-mix(in srgb, var(--c) 70%, black); }
.unit-seen { display: block; height: 6px; margin-top: .5rem; border-radius: 3px; background: var(--line); overflow: hidden; }
.unit-seen i { display: block; height: 100%; background: var(--c); opacity: .6; }
.dots .dot.seen::after { background: color-mix(in srgb, var(--c) 35%, white); }
.store-note { max-width: 520px; margin: 0 auto .4rem !important; line-height: 1.6; }
.link-btn { border: 0; background: none; color: var(--ink-2); text-decoration: underline; text-underline-offset: 2px; font-size: .9rem; min-height: 44px; padding: 0 .6rem; }

/* ---------- scam inbox ---------- */

.w-inbox { display: flex; flex-direction: column; gap: 10px; }
.ib-left { margin: 0; font-weight: 800; }
.msgs { display: grid; grid-template-columns: repeat(auto-fill, minmax(min(100%, 260px), 1fr)); gap: 10px; }
.msg-card { display: flex; flex-direction: column; gap: 6px; padding: 10px 12px; border-radius: 16px; background: var(--card); border: 2px solid var(--line); }
.msg-card .from { margin: 0; font-weight: 800; }
.msg-card .body { margin: 0; padding: .5rem .7rem; border-radius: 12px; background: #e9ecef; line-height: 1.5; }
.ib-btns { display: flex; gap: 8px; }
.ib-btns .option { flex: 1; min-height: 48px; padding: .3rem .5rem; font-size: 1rem; }
.msg-card.judged .ib-btns { display: none; }
.msg-card.is-scam { border-color: #ffa8a8; background: #fff5f5; }
.msg-card.is-ok { border-color: #8ce99a; background: #ebfbee; }
.msg-card .why { margin: 0; font-weight: 700; line-height: 1.5; font-size: .95rem; }

/* web traps: one case at a time in a drawn iPad browser */
.w-webtrap { display: flex; flex-direction: column; align-items: center; gap: 10px; }
.wt-ask { margin: 0; min-height: 1.6em; font-weight: 800; font-size: 1.1rem; text-align: center; }
.wt-ipad { width: min(100%, 540px); padding: 12px; border-radius: 26px; background: #1f232b; box-shadow: var(--shadow); }
.wt-screen { position: relative; aspect-ratio: 4 / 2.7; overflow: hidden; border-radius: 12px; background: white; font-size: .95rem; }
.wt-bar { display: flex; align-items: center; gap: 6px; margin: 8px; padding: 6px 10px; border-radius: 10px; background: #f1f3f5; font-size: .9rem; }
.wt-lock { flex: none; font-weight: 800; }
.wt-lock.wt-bad { color: #c92a2a; }
.wt-url { min-width: 0; overflow: hidden; text-overflow: ellipsis; white-space: nowrap; font-family: ui-monospace, Menlo, monospace; }
.wt-page { padding: 4px 16px; line-height: 1.6; }
.wt-page p { margin: 0 0 6px; }
.wt-site { font-weight: 900; font-size: 1.15rem; }
.wt-q { padding: 4px 10px; border-radius: 99px; border: 1px solid #dee2e6; width: fit-content; }
.wt-res { display: flex; flex-direction: column; margin: 8px 0; padding: 6px 8px; border-radius: 8px; }
.wt-res small { width: fit-content; padding: 0 6px; border-radius: 4px; background: #fff3bf; font-weight: 800; }
.wt-res b { color: #1971c2; }
.wt-res em { font-style: normal; color: #2b8a3e; font-size: .85rem; }
.wt-grid { display: flex; gap: 10px; }
.wt-grid span { flex: 1; padding: 8px; border-radius: 10px; background: #f8f9fa; text-align: center; font-size: 1.4rem; line-height: 1.2; }
.wt-ad { display: flex; flex-direction: column; margin-top: 8px; padding: 6px 10px; border-radius: 8px; border: 1px solid #dee2e6; color: var(--ink-2); font-size: .85rem; }
.wt-ad small { color: var(--ink-3); }
.wt-btn { display: inline-block; margin-top: 6px; padding: 4px 14px; border-radius: 8px; background: #e03131; color: white; font-weight: 800; }
.wt-layer { position: absolute; inset: 0; display: grid; place-items: center; pointer-events: none; }
.wt-layer:empty { display: none; }
.wt-pop, .wt-alert { width: 78%; padding: 12px; border-radius: 14px; background: #fff9db; box-shadow: 0 10px 30px rgba(0, 0, 0, .35); text-align: center; }
.wt-alert { background: #fff5f5; border: 3px solid #e03131; }
.wt-pop b, .wt-alert b, .wt-big b { display: block; font-size: 1.05rem; }
.wt-pop p, .wt-alert p, .wt-big p { margin: 4px 0; }
.wt-big { margin-top: 6px; padding: 12px; border-radius: 12px; background: #fff3bf; text-align: center; }
.wt-login { display: flex; flex-direction: column; align-items: center; gap: 6px; }
.wt-in { width: 60%; padding: 4px 10px; border-radius: 8px; border: 1px solid #ced4da; color: var(--ink-3); }
.wt-login .wt-btn { background: #1971c2; }
.wt-going { color: var(--ink-3); font-weight: 800; text-align: center; margin-top: 30px !important; }
/* after a right answer, the clue lights up */
.wt-show .wt-c { outline: 3px solid #e03131; outline-offset: 2px; border-radius: 6px; animation: wt-blink 1s ease-in-out 2; }
@keyframes wt-blink { 50% { outline-color: transparent; } }
.wt-btns { display: flex; gap: 12px; }
.wt-btns .option.right { border-color: var(--good); background: #ebfbee; }
.wt-why { margin: 0; width: min(100%, 540px); padding: 8px 12px; border-radius: 12px; line-height: 1.6; font-weight: 700; }
.wt-why.wt-try { background: #f1f3f5; color: var(--ink-2); }
.wt-why.wt-is-scam { background: #fff5f5; color: #a61e1e; }
.wt-why.wt-is-ok { background: #ebfbee; color: #1b5e20; }
.wt-foot { display: flex; align-items: center; justify-content: center; flex-wrap: wrap; gap: 12px; font-weight: 800; color: var(--ink-2); }
.wt-adbox { position: relative; }
.wt-x { position: absolute; top: 3px; right: 4px; width: 16px; height: 16px; padding: 0; border: 0; border-radius: 50%; background: rgba(0, 0, 0, .25); color: white; font-size: 11px; line-height: 16px; touch-action: manipulation; }
.wt-oops { display: flex; align-items: center; justify-content: space-between; gap: 8px; padding: 4px 8px; border-radius: 8px; background: #fff5f5; color: #a61e1e; font-weight: 800; }
.wt-back { min-height: 36px; padding: 0 10px; border: 2px solid var(--line); border-radius: 10px; background: white; font-weight: 800; }
.wt-note { color: var(--good); font-weight: 800; }

/* ---------- input methods ---------- */

.ime { display: flex; flex-direction: column; gap: 8px; padding: 12px; border-radius: var(--radius); background: #d5d9de; }
.ime-text { min-height: 56px; padding: .6rem .8rem; border-radius: 12px; background: white; font-size: 1.6rem; }
.ime-text u { text-decoration-color: var(--c); text-decoration-thickness: 3px; }
.cands { display: flex; flex-wrap: wrap; gap: 6px; min-height: 48px; align-items: center; }
.cand { min-width: 52px; min-height: 48px; border: 0; border-radius: 10px; background: white; font-size: 1.5rem; }
.cands .hint { margin: 0; }
.kbd { display: flex; flex-direction: column; align-items: center; gap: 6px; }
.krow { display: flex; flex-wrap: wrap; justify-content: center; gap: 6px; }
.kk { min-width: 48px; min-height: 52px; padding: 0 .5rem; border: 0; border-radius: 10px; background: white; font-size: 1.35rem; box-shadow: 0 2px 0 #adb5bd; }
.kk:active { transform: translateY(2px); box-shadow: none; }
.kk.tone { background: #f1f3f5; font-size: 1.1rem; }
.pad-ink { width: min(100%, 320px); height: auto; aspect-ratio: 32 / 17; border-radius: 12px; background: white; touch-action: none; }
.kbd-bar { display: flex; align-items: center; gap: 6px; }
.kbd-bar .mode-name { flex: 1; text-align: center; font-weight: 800; }

/* ---------- settings ---------- */

/* the phone and the panel sit side by side, and the checklist goes below them,
   so the whole task fits a laptop screen without scrolling */
.w-lab:has(> .set-wrap) { grid-template-columns: 1fr; }
.w-lab:has(> .set-wrap) > .tasks { display: grid; grid-template-columns: repeat(auto-fill, minmax(200px, 1fr)); gap: 4px 12px; }
.set-wrap { display: flex; gap: 14px; justify-content: center; align-items: stretch; }
.set-phone { position: relative; width: 220px; padding: 10px 12px; border-radius: 26px; border: 8px solid #111; background: white; transition: filter .2s; overflow: hidden; }
.set-status { display: flex; justify-content: space-between; align-items: center; gap: 4px; font-weight: 800; font-size: .85rem; }
.badge { font-size: .75rem; color: var(--ink-2); }
.banner { position: absolute; left: 8px; right: 8px; top: 30px; padding: .5rem .6rem; border-radius: 14px; background: rgba(241, 243, 245, .97); box-shadow: 0 4px 14px rgba(0,0,0,.15); font-size: .9rem; line-height: 1.4; }
.sample { margin: 3.4rem 0 0; line-height: 1.7; transition: font-size .2s; }
.set-panel { display: flex; flex-direction: column; gap: 4px; min-width: 240px; padding: 10px 12px; border-radius: var(--radius); background: var(--card); border: 2px solid var(--line); }
.srow { display: flex; align-items: center; justify-content: space-between; gap: 10px; min-height: 44px; font-weight: 700; border-bottom: 1px solid var(--line); }
.srow input[type="range"] { width: 130px; height: 44px; accent-color: var(--c); }
.set-sub { margin: .4rem 0 0; font-weight: 800; color: var(--ink-2); }
.sw { position: relative; flex: none; width: 60px; height: 36px; border: 0; border-radius: 18px; background: #ced4da; transition: background .2s; }
.sw::before { content: ''; position: absolute; inset: -6px; }
.sw::after { content: ''; position: absolute; top: 3px; left: 3px; width: 30px; height: 30px; border-radius: 50%; background: white; box-shadow: 0 1px 3px rgba(0,0,0,.3); transition: transform .2s; }
.sw.on { background: #40c057; }
.sw.on::after { transform: translateX(24px); }
@media (max-width: 560px) { .set-wrap { flex-wrap: wrap; } .set-phone { height: 300px; } }

/* ---------- screenshot ---------- */

.w-shot { display: flex; flex-direction: column; align-items: center; gap: 12px; }
.shot-dev { position: relative; width: 300px; height: 220px; padding: 14px; border-radius: 22px; background: #212529; }
.shot-screen { position: relative; width: 100%; height: 100%; display: flex; flex-direction: column; align-items: center; justify-content: center; border-radius: 8px; background: #fff3bf; font-size: 3rem; overflow: hidden; }
.shot-screen b { font-size: 1.2rem; }
.shot-thumb { position: absolute; left: 8px; bottom: 8px; padding: 4px 10px; border-radius: 8px; border: 3px solid white; background: #fff3bf; font-size: 1.4rem; box-shadow: 0 4px 10px rgba(0,0,0,.3); }
.hw { position: absolute; border: 0; background: #868e96; color: white; font-weight: 800; font-size: .8rem; touch-action: none; -webkit-user-select: none; user-select: none; }
.hw::before { content: ''; position: absolute; inset: -12px; }
.hw.down { background: var(--c); }
.hw.top { top: -22px; right: 40px; width: 74px; height: 24px; border-radius: 6px 6px 0 0; }
.hw.volup { right: -24px; top: 30px; width: 26px; height: 54px; border-radius: 0 6px 6px 0; }
.hw.voldn { right: -24px; top: 92px; width: 26px; height: 54px; border-radius: 0 6px 6px 0; }
.w-shot .readout { margin: .6rem 0 0; font-weight: 800; text-align: center; }
.keys-list { margin: 0; padding-left: 1.2rem; color: var(--ink-2); line-height: 1.7; font-size: .95rem; }

/* ---------- QR ---------- */

.qr-row { display: flex; flex-wrap: wrap; justify-content: center; gap: 16px; }
.qr-card { position: relative; display: flex; flex-direction: column; align-items: center; gap: 8px; width: min(100%, 260px); margin: 0; padding: 12px; border-radius: var(--radius); background: var(--card); border: 2px solid var(--line); text-align: center; }
.qr-card img { width: 150px; height: 150px; background: white; image-rendering: pixelated; }
.qr-card.fake img { rotate: -6deg; box-shadow: 3px 3px 0 #ced4da; }
.qr-card figcaption { font-weight: 700; }
.qr-card.done { border-color: var(--good); }
.qr-pop { display: flex; flex-direction: column; gap: 6px; width: 100%; padding: 8px; border-radius: 12px; background: var(--paper); }
.qr-pop p { margin: 0; font-size: .95rem; overflow-wrap: anywhere; }
.qr-pop code { font-weight: 800; }
.qr-pop div { display: flex; gap: 6px; justify-content: center; }
.qr-pop .option { min-height: 44px; padding: .2rem .7rem; font-size: 1rem; }
.qr-res { font-weight: 700; line-height: 1.5; }

/* ---------- Find My ---------- */

.fm-map-box { display: flex; flex-direction: column; gap: 8px; }
.fm-map { position: relative; height: 200px; border-radius: var(--radius); background: #e9f5db; background-image: linear-gradient(90deg, transparent 46%, #fff 46%, #fff 54%, transparent 54%), linear-gradient(0deg, transparent 44%, #fff 44%, #fff 52%, transparent 52%); }
.fm-home { position: absolute; left: 30%; top: 22%; font-size: 2.6rem; }
.fm-pin { position: absolute; left: 40%; top: 40%; font-size: 2rem; filter: drop-shadow(0 0 8px #4dabf7); }
.fm-park { position: absolute; right: 12%; bottom: 12%; font-size: 2.4rem; }
.fm-name { margin: 0; }
.fm-acts { display: flex; flex-wrap: wrap; gap: 8px; }
.fm-acts .option { font-size: 1rem; min-height: 48px; padding: .3rem .8rem; }
.fm-lock { padding: .8rem; border-radius: 16px; background: #212529; color: white; text-align: center; font-weight: 800; line-height: 1.6; }
.fm-map-box .readout { margin: 0; font-weight: 700; }

/* ---------- AI chat ---------- */

.chat { display: flex; flex-direction: column; gap: 10px; }
.chat-log { display: flex; flex-direction: column; gap: 8px; height: 280px; overflow-y: auto; padding: 10px; border-radius: var(--radius); background: var(--card); border: 2px solid var(--line); }
.bot-msg, .me-msg, .fix-msg { max-width: 85%; margin: 0; padding: .5rem .8rem; border-radius: 14px; line-height: 1.6; }
.bot-msg { align-self: flex-start; background: #e6fcf5; }
.me-msg { align-self: flex-end; background: var(--c); color: white; }
.fix-msg { align-self: center; background: #fff9db; font-weight: 700; font-size: .95rem; }
.judge { display: flex; gap: 6px; margin-top: 6px; }
.judge .option, .chat-qs .option { min-height: 44px; padding: .2rem .7rem; font-size: 1rem; }
.chat-qs { display: flex; flex-wrap: wrap; gap: 6px; }
.chat-qs .option:disabled { opacity: .4; }

/* ---------- multitasking ---------- */

.w-multi { display: flex; flex-direction: column; gap: 12px; align-items: center; }
.mt-rows { display: flex; flex-direction: column; gap: 8px; width: min(100%, 460px); }
.mt-row { display: grid; grid-template-columns: 120px 1fr; align-items: center; gap: 10px; padding: 8px 10px; border-radius: 12px; background: var(--card); border: 2px solid var(--line); transition: border-color .1s, background .1s; }
.mt-row.on { border-color: var(--c); background: color-mix(in srgb, var(--c) 10%, white); }
.mt-name { font-weight: 800; }
.mt-bar { height: 16px; border-radius: 8px; background: var(--line); overflow: hidden; }
.mt-bar i { display: block; height: 100%; width: 0; background: var(--c); }
.w-multi .readout { margin: 0; font-weight: 800; text-align: center; }
.w-multi .controls .option.on { border-color: var(--c); background: color-mix(in srgb, var(--c) 12%, white); }

/* ---------- number guess ---------- */

.w-guess { display: flex; flex-direction: column; gap: 10px; align-items: center; }
.g-step, .g-say { margin: 0; font-weight: 800; text-align: center; font-size: 1.1rem; line-height: 1.6; }
.g-say b { font-size: 1.6rem; color: var(--c); }
.g-grid { display: grid; grid-template-columns: repeat(8, 1fr); gap: 4px; width: min(100%, 420px); }
.g-n { min-height: 44px; border: 0; border-radius: 8px; background: var(--card); font-weight: 700; box-shadow: 0 1px 0 var(--line); }
.g-n.out { opacity: .2; }
.g-n.guess { background: var(--c); color: white; }
.g-n.mine { outline: 3px solid var(--star); }
.g-n.hit { background: var(--good); color: white; animation: g-cheer .9s ease-out 2; position: relative; z-index: 1; }
@keyframes g-cheer { 30% { scale: 1.5; box-shadow: 0 0 0 8px rgba(43, 138, 62, .25); } 100% { scale: 1; } }
.g-yes { display: inline-block; color: var(--good); font-size: 1.4rem; animation: g-pop .5s ease-out; }
@keyframes g-pop { from { scale: .3; opacity: 0; } 70% { scale: 1.2; } to { scale: 1; opacity: 1; } }
@media (prefers-reduced-motion: reduce) { .g-n.hit, .g-yes { animation: none; } }
.g-play { display: flex; flex-direction: column; gap: 8px; align-items: center; }

/* ---------- swap sort ---------- */

.w-swap { display: flex; flex-direction: column; gap: 12px; align-items: center; }
.cards-row { display: flex; flex-wrap: wrap; align-items: center; justify-content: center; gap: 4px; }
.ncard { display: grid; place-items: center; width: 56px; height: 76px; border-radius: 12px; background: var(--card); border: 3px solid var(--c); font-size: 1.8rem; font-weight: 900; }
.swapbtn { width: 44px; height: 48px; border: 0; border-radius: 10px; background: var(--paper); font-size: 1.2rem; }
.swapbtn:active { background: color-mix(in srgb, var(--c) 20%, white); }
.w-swap .readout { margin: 0; font-weight: 800; text-align: center; }
.srt-demo { display: flex; flex-direction: column; align-items: center; gap: 8px; width: min(100%, 520px); margin-top: 6px; padding-top: 12px; border-top: 2px dashed var(--line); }
.srt-h { margin: 0; font-weight: 800; }
.srt-demo .controls { display: flex; flex-wrap: wrap; justify-content: center; gap: 8px; }
.srt-demo .controls .option { min-height: 48px; }
.srt-demo .controls .option.on { border-color: var(--c); background: color-mix(in srgb, var(--c) 12%, white); }
.srt-bars { position: relative; width: 100%; height: 150px; border-radius: 14px; background: var(--card); border: 2px solid var(--line); }
.srt-bar { position: absolute; bottom: 6px; width: calc(100% / 8 - 8px); margin-left: 4px; display: flex; align-items: flex-start; justify-content: center; max-height: calc(100% - 12px); border-radius: 6px 6px 2px 2px; background: #adb5bd; color: white; font-weight: 900; transition: left .3s ease-in-out, background .15s; }
.srt-bar b { margin-top: 2px; font-size: .9rem; }
.srt-bar.cmp { background: #fab005; }
.srt-bar.swap { background: #fa5252; }
.srt-bar.pivot { background: #7950f2; }
.srt-bar.done { background: var(--good); }
.srt-say { margin: 0; min-height: 3em; text-align: center; font-weight: 700; line-height: 1.5; }
.srt-say small { color: var(--ink-3); }
.srt-score { margin: 0; min-height: 1.5em; text-align: center; font-weight: 800; color: var(--ink-2); line-height: 1.6; }
@media (prefers-reduced-motion: reduce) { .srt-bar { transition: none; } }

/* ---------- run-length decoding ---------- */

.w-rle { display: flex; flex-wrap: wrap; align-items: flex-start; justify-content: center; gap: 16px; }
.rle-pair { display: flex; align-items: stretch; gap: 8px; }
.rle-codes { list-style: none; margin: 0; padding: 6px 0; display: grid; grid-template-rows: repeat(var(--rows), 1fr); gap: 3px; font-weight: 800; font-size: 1.15rem; }
.rle-codes li { display: flex; align-items: center; justify-content: flex-end; gap: 6px; white-space: nowrap; }
.rle-arrow { color: var(--c); font-weight: 900; }
.w-rle .canvas { background: #adb5bd; }
.w-rle .canvas .px { background: white; }
.w-rle .canvas .px.on { background: var(--px); }
.w-rle .canvas { width: min(300px, 60vw); }
.w-rle .hint { flex-basis: 100%; }

/* ---------- AI training ---------- */

.w-train { display: flex; flex-direction: column; gap: 12px; align-items: center; }
.tr-box { width: min(100%, 460px); padding: 10px 12px; border-radius: var(--radius); background: var(--card); border: 2px solid var(--line); }
.tr-box p { margin: 0 0 6px; font-weight: 800; }
.tr-ex { display: flex; flex-wrap: wrap; gap: 8px; }
.tr-chip { display: flex; flex-direction: column; align-items: center; padding: 4px 10px; border-radius: 12px; background: var(--paper); font-size: 2rem; }
.tr-chip small { font-size: .8rem; font-weight: 700; }
.tr-test { display: flex; align-items: center; gap: 14px; width: min(100%, 460px); }
.tr-item { font-size: 4rem; }
.tr-say { margin: 0; font-size: 1.1rem; line-height: 1.6; }

/* Center the text and the task in landscape without clipping a task that is taller
   than the screen: auto margins center when there is room and collapse when there
   is not, so the slide scrolls instead of cutting off the top. */
@media (min-width: 900px) and (orientation: landscape) {
  .slide.has-widget { align-items: stretch; }
  .slide.has-widget .words { margin-block: auto; }
  .slide.has-widget .stage { justify-content: flex-start; }
  .slide.has-widget .stage > * { margin-block: auto; }
}

/* ---------- undo / redo ---------- */

.ud-box { display: flex; flex-direction: column; gap: 10px; }
.ud-bar { display: flex; gap: 8px; }
.ud-bar .option { min-height: 48px; padding: .3rem 1rem; font-size: 1.05rem; }
.ud-bar .option:disabled { opacity: .4; }
.ud-scene { display: flex; flex-wrap: wrap; align-items: center; gap: 8px; min-height: 120px; padding: 12px; border-radius: var(--radius); background: linear-gradient(#e7f5ff 65%, #d3f9d8 65%); font-size: 2.6rem; }
.ud-scene em { font-size: 1rem; color: var(--ink-3); font-style: normal; }
.ud-picks { display: flex; flex-wrap: wrap; gap: 8px; }
.ud-picks .option { min-width: 56px; min-height: 52px; font-size: 1.6rem; text-align: center; padding: .2rem .5rem; }
.ud-stacks p { margin: 0; font-weight: 700; color: var(--ink-2); }

/* ---------- pretend browser ---------- */

.brw { display: flex; flex-direction: column; gap: 8px; border-radius: var(--radius); background: var(--card); border: 2px solid var(--line); overflow: hidden; }
.br-bar { display: flex; align-items: center; gap: 6px; padding: 8px; background: #f1f3f5; }
.br-btn { flex: none; width: 48px; height: 48px; border: 0; border-radius: 12px; background: white; font-size: 1.4rem; font-weight: 800; }
.br-btn:disabled { opacity: .35; }
.br-url { flex: 1; display: flex; align-items: center; gap: 4px; min-width: 0; padding: 0 10px; border-radius: 12px; background: white; }
.br-url input { flex: 1; min-width: 0; min-height: 48px; border: 0; font: inherit; font-size: 16px; background: none; }
.br-page { display: flex; flex-direction: column; align-items: flex-start; gap: 8px; min-height: 170px; padding: 6px 16px 12px; }
.br-page h4 { margin: 0; font-size: 1.4rem; }
.br-page p { margin: 0; }
.br-page small { color: var(--ink-3); }
.br-link { min-height: 44px; padding: 0 .4rem; border: 0; background: none; color: #1971c2; text-decoration: underline; font-size: 1.1rem; font-weight: 700; }
.br-hint { margin: 0; padding: 4px 16px 0; color: var(--ink-2); }
.br-hint p { margin: 0 0 4px; font-weight: 800; }
.br-hint ol { margin: 0; padding-left: 1.4em; display: flex; flex-direction: column; gap: 4px; }
.br-hint li { padding: 2px 6px; border-radius: 8px; line-height: 1.6; }
.br-hint li.br-now { background: color-mix(in srgb, var(--c) 12%, white); color: var(--ink); font-weight: 800; }
.br-hint li.br-ok { color: var(--good); }
.br-hint li.br-ok::marker { content: '✓ '; }
.br-hint code { padding: 1px 6px; border-radius: 6px; background: #f1f3f5; font-family: ui-monospace, Menlo, monospace; font-weight: 800; color: var(--ink); }
.br-hint kbd { padding: 1px 6px; border: 1px solid #adb5bd; border-bottom-width: 3px; border-radius: 6px; background: white; font-family: inherit; font-weight: 800; }
.br-sug, .br-enter { min-height: 40px; padding: 0 10px; border: 2px solid var(--line); border-radius: 10px; background: var(--card); color: var(--ink); font: inherit; font-weight: 800; text-decoration: none; }
.br-enter { border-color: var(--c); }
.br-hist { padding: 8px 16px 12px; border-top: 1px solid var(--line); color: var(--ink-3); font-size: .95rem; }
.br-hist .hist-now { color: var(--ink); font-weight: 800; }

/* a task this device cannot do: still listed, as information */
.tasks li.na { opacity: .7; }
.tasks li.na .tick { border: 0; font-size: 18px; line-height: 24px; text-align: center; }
.tasks li.na .alt { color: var(--ink-2); }

/* ---------- system gestures: a drawn iPad with room around it to start a swipe outside the screen ---------- */

/* --gw: as wide as fits, leaving height for the message row and the checklist */
.w-gs { --gw: min(100%, calc((100dvh - 430px) * 1.55)); display: flex; flex-direction: column; gap: 10px; align-items: center; }
.gs-say { display: flex; align-items: center; flex-wrap: wrap; gap: 8px; width: var(--gw); }
.gs-msg { flex: 1; min-width: 12em; font-weight: 800; font-size: 1.1rem; line-height: 1.4; }
.gs-msg > b:first-child { font-size: 1.3rem; }
.gs-say button { min-height: 44px; padding: 0 14px; border: 2px solid var(--line); border-radius: 12px; background: var(--card); font-weight: 800; }
.gs-say button:disabled { opacity: .45; }
.gs-say button.glow { border-color: var(--c); animation: glow 1.4s infinite; }
.gs-next { background: var(--c) !important; border-color: var(--c) !important; color: white; }

.gs-stage {
  position: relative;
  width: var(--gw);
  aspect-ratio: 1.55;
  border-radius: var(--radius);
  background: repeating-linear-gradient(45deg, #f3eee3 0 10px, #f7f3ea 10px 20px);
  border: 2px dashed var(--line);
  touch-action: none;
  -webkit-user-select: none; user-select: none; -webkit-touch-callout: none;
  overflow: hidden;
}
.gs-ink { position: absolute; inset: 0; width: 100%; height: 100%; pointer-events: none; z-index: 5; }
.gs-ipad {
  position: absolute; left: 50%; top: 50%; translate: -50% -50%;
  height: 76%; aspect-ratio: 1.38;
  padding: 2.6%;
  border-radius: 6% / 8.3%;
  background: #1f232b;
  box-shadow: 0 10px 24px rgba(29, 39, 56, .25), inset 0 0 0 2px #3a404c;
  container-type: inline-size;
}
.gs-screen {
  position: relative; width: 100%; height: 100%;
  overflow: hidden;
  border-radius: 3.4% / 4.6%;
  background: linear-gradient(160deg, #74c0fc, #b197fc 60%, #f783ac);
  font-size: 3.4cqw;
}
.gs-status { position: absolute; inset: 0 0 auto; z-index: 4; display: flex; justify-content: space-between; padding: .5% 4%; font-size: .8em; font-weight: 800; color: #1d2738; pointer-events: none; }
.gs-home { position: absolute; inset: 9% 6% 4%; display: grid; grid-template-columns: repeat(4, 1fr); align-content: start; gap: 6% 4%; transition: filter .3s, transform .3s; }
.gs-icon { display: flex; flex-direction: column; align-items: center; gap: 3px; font-size: .62em; font-weight: 800; color: white; text-shadow: 0 1px 2px rgba(0, 0, 0, .35); }
.gs-icon b, .gs-dock b { display: grid; place-items: center; width: 2.6em; aspect-ratio: 1; border-radius: 24%; background: rgba(255, 255, 255, .9); font-size: 1.6em; text-shadow: none; }
.gs-dock { position: absolute; left: 50%; bottom: 0; translate: -50% 0; display: flex; gap: .5em; padding: .4em; border-radius: .9em; background: rgba(255, 255, 255, .35); font-size: .62em; }
.gs-dock b { width: 2.3em; }

.gs-card { position: absolute; inset: 0; z-index: 2; display: flex; flex-direction: column; background: white; transition: transform .35s ease, opacity .35s ease, border-radius .35s; transform-origin: 50% 50%; }
.gs-card p { margin: 0; padding: 5.5% 4% 2%; font-weight: 900; font-size: .9em; border-bottom: 1px solid #eee; }
.gs-card > span { flex: 1; display: grid; place-items: center; font-size: 2.6em; }
.gs-art { display: flex !important; justify-content: center; align-items: center; gap: .3em; background: #fffdf5; }
.gs-art i { font-style: normal; transition: opacity .3s, transform .3s; }
.undone .gs-last { opacity: 0; transform: scale(.3); }
.gs-other { opacity: 0; pointer-events: none; background: #343a40; color: white; }
.gs-other p { border-color: #495057; }
/* in an app: the app covers the home screen; on the home screen it shrinks into its icon */
.on-home .gs-app { transform: translate(-37%, -36%) scale(.08); opacity: 0; border-radius: 30%; }
.show-cards .gs-home { filter: blur(3px) brightness(.8); }
.show-cards .gs-app { transform: translateX(22%) scale(.52); border-radius: 4%; box-shadow: 0 8px 20px rgba(0, 0, 0, .3); }
.show-cards .gs-other { opacity: 1; transform: translateX(-30%) scale(.52); border-radius: 4%; box-shadow: 0 8px 20px rgba(0, 0, 0, .3); }

.gs-search, .gs-nc, .gs-cc { position: absolute; z-index: 3; transform: translateY(-110%); transition: transform .35s ease; }
.gs-search { left: 15%; right: 15%; top: 0; display: flex; flex-direction: column; gap: .3em; padding: 7% 3% 3%; border-radius: 0 0 .8em .8em; background: rgba(255, 255, 255, .95); font-size: .8em; font-weight: 800; }
.gs-search p { margin: 0 0 .2em; padding: .3em .6em; border-radius: .6em; background: #eef1f5; color: #6b7280; }
.show-search .gs-search { transform: none; }
.show-search .gs-home { filter: blur(3px); }
.gs-nc { inset: 0; display: flex; flex-direction: column; gap: .5em; padding: 8% 20% 0; background: rgba(29, 39, 56, .55); backdrop-filter: blur(6px); -webkit-backdrop-filter: blur(6px); color: white; font-size: .8em; font-weight: 800; }
.gs-nc p { margin: 0 0 .3em; font-size: 1.4em; }
.gs-nc span { padding: .7em 1em; border-radius: .8em; background: rgba(255, 255, 255, .9); color: #1d2738; }
.show-nc .gs-nc { transform: none; }
.gs-cc { right: 3%; top: 8%; width: 40%; display: grid; grid-template-columns: repeat(4, 1fr); gap: .4em; padding: .6em; border-radius: 1em; background: rgba(40, 44, 52, .75); backdrop-filter: blur(6px); -webkit-backdrop-filter: blur(6px); transform: translateY(-140%); }
.gs-cc b { display: grid; place-items: center; aspect-ratio: 1; border-radius: 30%; background: rgba(255, 255, 255, .85); font-size: 1em; }
.gs-cc .gs-wide { grid-column: span 2; aspect-ratio: auto; padding: .5em 0; font-size: .7em; }
.show-cc .gs-cc { transform: none; }
.gs-hud { position: absolute; left: 50%; top: 18%; translate: -50% 0; z-index: 4; padding: .4em .9em; border-radius: .7em; background: rgba(29, 39, 56, .85); color: white; font-weight: 800; font-size: .8em; white-space: nowrap; }
.gs-bar { position: absolute; left: 50%; bottom: 1.6%; translate: -50% 0; z-index: 4; width: 26%; height: 1.4%; min-height: 4px; border-radius: 9px; background: #1d2738; opacity: .75; pointer-events: none; }

.gs-tasks { width: var(--gw); display: grid !important; grid-template-columns: repeat(auto-fill, minmax(160px, 1fr)); gap: 2px 12px !important; }
.gs-tasks li { border-radius: 10px; cursor: default; }
.gs-tasks li.done { cursor: pointer; }
.gs-tasks li.gs-now { background: color-mix(in srgb, var(--c) 10%, white); outline: 2px solid var(--c); }
.w-gs .toast { white-space: normal; width: max-content; max-width: 90%; text-align: center; }
@media (orientation: portrait) { .gs-stage { aspect-ratio: 1.7; } }
@media (orientation: landscape) and (max-height: 740px) { .gs-tasks .alt { display: none; } }

/* ---------- the network picture: dotted world map, devices, and data dots on the lines ---------- */

.net-map { width: min(100%, 900px, calc((100dvh - 300px) * 2.25)); height: auto; display: block; border-radius: 18px; box-shadow: var(--shadow); }
.nm-land { stroke: #a9c1d6; stroke-width: 2.6; stroke-linecap: round; opacity: .45; }
.nm-line { fill: none; stroke: #74c0fc; stroke-width: 2; opacity: .75; }
.nm-stray { opacity: .3; }
.nm-beam { stroke-dasharray: 5 6; }
.nm-bit { fill: #ffe066; filter: drop-shadow(0 0 3px #ffe066); }
.nm-back { fill: #ffffff; filter: drop-shadow(0 0 3px #a5d8ff); }
.nm-badge { fill: rgba(255, 255, 255, .14); stroke: #74c0fc; stroke-width: 2; }
.nm-ring { fill: none; stroke: #74c0fc; stroke-width: 1; opacity: .35; }
@media (prefers-reduced-motion: reduce) { .nm-bit { display: none; } }

/* ---------- TLS: five animated steps between the browser and the website ---------- */

.w-tls { display: flex; flex-direction: column; align-items: center; gap: 12px; }
.tl-dots { list-style: none; display: flex; gap: 8px; margin: 0; padding: 0; }
.tl-dots li { display: grid; place-items: center; width: 32px; height: 32px; border-radius: 50%; background: var(--line); color: var(--ink-2); font-weight: 900; }
.tl-dots li.done { background: color-mix(in srgb, var(--c) 35%, white); color: white; }
.tl-dots li.on { background: var(--c); color: white; }
.tl-stage { display: flex; align-items: center; gap: 8px; width: min(100%, 560px); min-height: 190px; padding: 14px; border-radius: var(--radius); background: var(--card); border: 2px solid var(--line); }
.tl-side { position: relative; flex: none; display: flex; flex-direction: column; align-items: center; gap: 2px; width: 92px; }
.tl-side > span { font-size: 3rem; line-height: 1.1; }
.tl-side b { font-weight: 800; }
.tl-near { min-height: 48px; display: grid; place-items: center; font-size: 1.8rem; }
.tl-path { position: relative; flex: 1; align-self: stretch; display: grid; place-items: center; }
.tl-path::before { content: ''; position: absolute; left: 0; right: 0; top: 40%; border-top: 3px dashed var(--line); }
.tl-tok { position: absolute; top: 40%; translate: -50% -50%; padding: 4px 10px; border-radius: 99px; background: #fff9db; border: 2px solid #ffd43b; font-weight: 800; white-space: nowrap; }
.tl-tok.tl-locked { background: color-mix(in srgb, var(--c) 12%, white); border-color: var(--c); }
.tl-mid { position: relative; top: 22%; font-size: 2rem; }
.tl-spy { display: flex; flex-direction: column; align-items: center; }
.tl-spy small { font-size: .8rem; font-weight: 800; color: var(--ink-3); }
.tl-card { position: relative; }
.tl-mag { position: absolute; left: 10px; top: -6px; font-size: 1.3rem; animation: tl-scan 1.2s ease-in-out 2; }
.tl-ok { position: absolute; right: -18px; top: -14px; font-size: 1.2rem; opacity: 0; animation: tl-stamp .4s ease-out 2.4s forwards; }
@keyframes tl-scan { 0%, 100% { translate: -14px 0; } 50% { translate: 14px 8px; } }
@keyframes tl-stamp { from { opacity: 0; scale: 2; } to { opacity: 1; scale: 1; } }
.tl-key { animation: tl-glint 1.2s ease-out; }
@keyframes tl-glint { from { opacity: 0; scale: .3; rotate: -90deg; } to { opacity: 1; scale: 1; rotate: 0deg; } }
.tl-shake { display: inline-block; animation: tl-wave .5s ease-in-out 3; }
@keyframes tl-wave { 50% { rotate: 12deg; } }
.tl-say { margin: 0; min-height: 3.2em; width: min(100%, 560px); font-weight: 800; font-size: 1.1rem; line-height: 1.6; text-align: center; }
@media (prefers-reduced-motion: reduce) { .tl-mag, .tl-key, .tl-shake { animation: none; } .tl-ok { animation: none; opacity: 1; } }