/* ═══════════════════════════════════════════════════════════════════════
   tingxins — studio hub
   Zero build. Zero framework. Zero webfonts.
   ═══════════════════════════════════════════════════════════════════════ */

/* ── animatable accent, so the per-act colour bleed interpolates ───────── */
@property --ac      { syntax: '<color>'; inherits: true; initial-value: #6EE7D6; }
@property --ac2     { syntax: '<color>'; inherits: true; initial-value: #8AB4FF; }
@property --ac-deep { syntax: '<color>'; inherits: true; initial-value: #0B1220; }

/* ── tokens ───────────────────────────────────────────────────────────── */
:root {
  --bg:    #08090C;
  --bg2:   #0B0C11;
  --card:  #111318;
  --card2: #15171D;
  --ink:   #E9EAEE;
  --ink2:  #A8AEBD;
  --mut:   #7E8496;
  --line:  #1E2028;
  --line2: #2A2D38;
  --ac:      #6EE7D6;
  --ac2:     #8AB4FF;
  --ac-deep: #0B1220;
  --shadow: 0 1px 2px rgb(0 0 0 / .5), 0 18px 50px -18px rgb(0 0 0 / .8);

  --wrap: 1200px;
  --pad:  clamp(20px, 5vw, 48px);
  --r:    16px;
  --r-lg: 24px;

  --font: -apple-system, BlinkMacSystemFont, "SF Pro Display", "SF Pro Text",
          "Segoe UI", "PingFang SC", "Hiragino Sans GB", "Microsoft YaHei",
          system-ui, Roboto, Helvetica, Arial, sans-serif;
  --mono: ui-monospace, SFMono-Regular, "SF Mono", Menlo, Consolas, monospace;

  --ease: cubic-bezier(.22,.68,0,1);
  --spring: cubic-bezier(.34,1.42,.44,1);

  color-scheme: dark;
}

:root[data-theme="light"] {
  --bg:    #F7F7F5;
  --bg2:   #FFFFFF;
  --card:  #FFFFFF;
  --card2: #F1F1EE;
  --ink:   #14161B;
  --ink2:  #434857;
  --mut:   #6B7180;
  --line:  #E5E5E1;
  --line2: #D2D3CE;
  --shadow: 0 1px 2px rgb(20 22 27 / .06), 0 20px 44px -22px rgb(20 22 27 / .30);
  color-scheme: light;
}

/* accent tuned for legibility against the current ground */
:root            { --ac-txt: var(--ac); --ac-soft: color-mix(in srgb, var(--ac) 14%, transparent); }
:root[data-theme="light"] { --ac-txt: color-mix(in srgb, var(--ac) 62%, #16181D 38%);
                            --ac-soft: color-mix(in srgb, var(--ac) 20%, transparent); }

/* the accent bleed interpolates because --ac is a registered property */
html { transition: --ac .7s var(--ease), --ac2 .7s var(--ease), --ac-deep .7s var(--ease); }
@media (prefers-reduced-motion: reduce) { html { transition: none; } }

/* ── bilingual: both languages in the DOM, one shown ───────────────────── */
html[data-lang="en"] [data-lang="zh"],
html[data-lang="zh"] [data-lang="en"] { display: none !important; }

/* ── reset / base ─────────────────────────────────────────────────────── */
*, *::before, *::after { box-sizing: border-box; }
* { margin: 0; }

html { -webkit-text-size-adjust: 100%; scroll-behavior: smooth; scroll-padding-top: 88px; }

body {
  background: var(--bg);
  color: var(--ink);
  font-family: var(--font);
  font-size: 16px;
  line-height: 1.6;
  -webkit-font-smoothing: antialiased;
  -moz-osx-font-smoothing: grayscale;
  overflow-x: hidden;
  transition: background .6s var(--ease), color .3s linear;
}

img, svg, canvas { display: block; max-width: 100%; }
img { height: auto; }
button { font: inherit; color: inherit; background: none; border: 0; cursor: pointer; }
ul[class], ol[class] { list-style: none; padding-inline-start: 0; }
a { color: inherit; text-decoration: none; }
:where(h1,h2,h3,h4) { line-height: 1.1; font-weight: 620; letter-spacing: -.022em; text-wrap: balance; }
p { text-wrap: pretty; }

:focus-visible {
  outline: 2px solid var(--ac-txt);
  outline-offset: 3px;
  border-radius: 6px;
}

.wrap { width: 100%; max-width: var(--wrap); margin-inline: auto; padding-inline: var(--pad); }

.skip {
  position: fixed; top: -100px; left: 16px; z-index: 200;
  padding: 10px 16px; border-radius: 10px;
  background: var(--ink); color: var(--bg); font-weight: 600;
  transition: top .2s var(--ease);
}
.skip:focus { top: 16px; }

/* ── atmosphere ───────────────────────────────────────────────────────── */
.grain {
  position: fixed; inset: 0; z-index: 90; pointer-events: none;
  opacity: .035; mix-blend-mode: overlay;
  background-image: url("data:image/svg+xml,%3Csvg xmlns='http://www.w3.org/2000/svg' width='140' height='140'%3E%3Cfilter id='n'%3E%3CfeTurbulence type='fractalNoise' baseFrequency='.85' numOctaves='3'/%3E%3C/filter%3E%3Crect width='140' height='140' filter='url(%23n)'/%3E%3C/svg%3E");
}
:root[data-theme="light"] .grain { opacity: .05; mix-blend-mode: multiply; }

.glow {
  position: fixed; inset: 0; z-index: -1; pointer-events: none;
  background:
    radial-gradient(70ch 60ch at 78% -10%, color-mix(in srgb, var(--ac) 13%, transparent), transparent 62%),
    radial-gradient(60ch 50ch at 8% 12%,  color-mix(in srgb, var(--ac2) 9%, transparent), transparent 60%);
  transition: background .8s var(--ease);
}

/* ═══════════════════════  HEADER  ═══════════════════════ */
.site-head {
  position: sticky; top: 0; z-index: 100;
  border-bottom: 1px solid transparent;
  transition: background .35s var(--ease), border-color .35s var(--ease), backdrop-filter .35s;
}
.site-head.is-stuck {
  background: color-mix(in srgb, var(--bg) 78%, transparent);
  backdrop-filter: saturate(180%) blur(18px);
  -webkit-backdrop-filter: saturate(180%) blur(18px);
  border-bottom-color: var(--line);
}
.site-head__in { display: flex; align-items: center; gap: 24px; height: 64px; }

.brand { display: flex; align-items: center; gap: 9px; font-weight: 650; letter-spacing: -.02em; }
.brand__dot {
  width: 9px; height: 9px; border-radius: 50%;
  background: var(--ac);
  box-shadow: 0 0 0 4px color-mix(in srgb, var(--ac) 18%, transparent);
  transition: background .6s var(--ease), box-shadow .6s var(--ease);
}
.brand__name { font-size: 15px; }

.site-nav { display: flex; gap: 4px; margin-left: auto; }
.site-nav a {
  padding: 7px 12px; border-radius: 9px; font-size: 13.5px; color: var(--ink2);
  transition: color .18s, background .18s;
}
.site-nav a:hover { color: var(--ink); background: color-mix(in srgb, var(--ink) 7%, transparent); }

.head-tools { display: flex; gap: 6px; }
.tool {
  min-width: 46px; height: 34px; padding: 0 11px;
  display: inline-flex; align-items: center; justify-content: center;
  border: 1px solid var(--line2); border-radius: 10px;
  font-size: 12.5px; font-weight: 560; color: var(--ink2);
  transition: color .18s, border-color .18s, background .18s;
}
.tool:hover { color: var(--ink); border-color: var(--ac); background: var(--ac-soft); }
.tool--icon { min-width: 34px; padding: 0; }
.tool--icon svg { fill: none; stroke: currentColor; stroke-width: 1.6; }
.t-moon { display: none; }
:root[data-theme="light"] .t-sun, :root[data-theme="light"] .t-rays { display: none; }
:root[data-theme="light"] .t-moon { display: block; fill: currentColor; stroke: none; }

/* ═══════════════════════  HERO  ═══════════════════════ */
.hero { padding: clamp(48px, 9vw, 110px) 0 clamp(40px, 6vw, 76px); }
.hero__in {
  display: grid; grid-template-columns: minmax(0, 1.05fr) minmax(0, .95fr);
  gap: clamp(28px, 5vw, 72px); align-items: center;
}

.eyebrow {
  display: inline-flex; align-items: center; gap: 9px;
  font-size: 12.5px; font-weight: 600; letter-spacing: .07em; text-transform: uppercase;
  color: var(--ink2);
}
.eyebrow__pip {
  width: 6px; height: 6px; border-radius: 50%; background: var(--ac);
  box-shadow: 0 0 0 0 color-mix(in srgb, var(--ac) 55%, transparent);
  animation: pip 2.6s var(--ease) infinite;
}
@keyframes pip {
  0%   { box-shadow: 0 0 0 0 color-mix(in srgb, var(--ac) 50%, transparent); }
  70%,100% { box-shadow: 0 0 0 9px color-mix(in srgb, var(--ac) 0%, transparent); }
}

.hero__title {
  margin: 18px 0 0;
  font-size: clamp(38px, 6.4vw, 74px);
  letter-spacing: -.038em;
  line-height: 1.03;
}
/* kinetic word reveal (words wrapped by JS) */
.kinetic .w { display: inline-block; overflow: hidden; vertical-align: bottom; padding-bottom: .06em; }
.kinetic .w > i {
  display: inline-block; font-style: inherit;
  transform: translateY(105%);
  animation: wordUp .9s var(--ease) forwards;
  animation-delay: calc(var(--i) * 55ms);
}
@keyframes wordUp { to { transform: translateY(0); } }

.hero__sub {
  margin-top: 22px; max-width: 46ch;
  font-size: clamp(15.5px, 1.5vw, 18.5px); color: var(--ink2);
}

.hero__cta { display: flex; flex-wrap: wrap; gap: 12px; margin-top: 30px; }

.btn {
  --tx: 0px; --ty: 0px;
  position: relative; display: inline-flex; align-items: center; gap: 8px;
  padding: 12px 20px; border-radius: 12px;
  font-size: 14.5px; font-weight: 570; letter-spacing: -.01em;
  transform: translate(var(--tx), var(--ty));
  transition: transform .35s var(--spring), background .25s, border-color .25s, color .25s;
}
.btn--sm { padding: 8px 14px; font-size: 13px; }
.btn--primary {
  background: var(--ac); color: #08090C;
  box-shadow: 0 6px 22px -8px color-mix(in srgb, var(--ac) 70%, transparent);
}
.btn--primary:hover { background: color-mix(in srgb, var(--ac) 88%, #fff); }
.btn--ghost { border: 1px solid var(--line2); color: var(--ink); }
.btn--ghost:hover { border-color: var(--ac); background: var(--ac-soft); }

.hero__stats {
  display: grid; grid-template-columns: repeat(3, minmax(0, 1fr)); gap: 14px 26px;
  margin-top: 40px; padding-top: 26px; border-top: 1px solid var(--line);
}
.hero__stats li { display: grid; gap: 5px; align-content: start; }
.hero__stats b {
  font-size: 12px; font-weight: 640; letter-spacing: .1em; text-transform: uppercase;
  color: var(--ac-txt);
}
.hero__stats li span { font-size: 13.5px; color: var(--ink2); }

.hero__art { position: relative; display: grid; justify-items: center; gap: 14px; }
#boundary { width: min(100%, 460px); height: auto; aspect-ratio: 1; }
.hero__art-cap {
  font-size: 12.5px; letter-spacing: .05em; text-transform: uppercase;
  color: var(--mut); font-weight: 560;
}

/* ═══════════════════════  MARQUEE BAND  ═══════════════════════ */
.band {
  overflow: hidden; padding: 15px 0;
  border-block: 1px solid var(--line);
  background: color-mix(in srgb, var(--ac) 4%, transparent);
  mask-image: linear-gradient(90deg, transparent, #000 8%, #000 92%, transparent);
}
.band__track { display: flex; width: max-content; animation: slide 44s linear infinite; }
.band__track span {
  display: inline-flex; align-items: center; gap: 22px; padding-right: 22px;
  font-size: 13px; letter-spacing: .1em; text-transform: uppercase;
  font-weight: 560; color: var(--ink2); white-space: nowrap;
}
.band__track span::after { content: "◈"; color: var(--ac); font-size: 10px; }
.band:hover .band__track { animation-play-state: paused; }
@keyframes slide { to { transform: translateX(-50%); } }

/* ═══════════════════════  ACTS  ═══════════════════════ */
.act { padding: clamp(60px, 10vw, 130px) 0; position: relative; }
.act + .act { border-top: 1px solid var(--line); }

.act__head {
  display: grid; grid-template-columns: auto auto 1fr auto; align-items: center;
  gap: 18px; padding-bottom: clamp(28px, 4vw, 48px);
}
.act__num {
  font-family: var(--mono); font-size: 12px; letter-spacing: .12em;
  color: var(--ac-txt); padding-top: 3px; align-self: start;
}
.act__icon {
  width: 60px; height: 60px; border-radius: 14px;
  box-shadow: var(--shadow); background: var(--card);
}
.act__name { font-size: clamp(26px, 3.4vw, 40px); letter-spacing: -.032em; }
.act__name em { font-style: normal; font-weight: 400; color: var(--mut); font-size: .58em; letter-spacing: -.01em; }
.act__pitch { margin-top: 5px; font-size: clamp(15px, 1.6vw, 18px); color: var(--ink2); }

.chips { display: flex; flex-wrap: wrap; gap: 7px; justify-self: end; }
.chip-tag {
  padding: 5px 11px; border-radius: 999px;
  border: 1px solid var(--line2); font-size: 12px; font-weight: 560; color: var(--ink2);
  white-space: nowrap;
}
.chip-tag:first-child { border-color: color-mix(in srgb, var(--ac) 45%, transparent); color: var(--ac-txt); }

.act__body {
  display: grid; grid-template-columns: minmax(0, 380px) minmax(0, 1fr);
  gap: clamp(32px, 5vw, 80px); align-items: start;
}
.act__stage { position: sticky; top: 92px; display: grid; gap: 18px; justify-items: center; }

/* ── device frame ── */
.device {
  --tx: 0deg; --ty: 0deg;
  position: relative; width: min(100%, 300px);
  transform: perspective(1200px) rotateX(var(--tx)) rotateY(var(--ty));
  transition: transform .5s var(--ease);
  transform-style: preserve-3d;
}
.device__glow {
  position: absolute; inset: -14% -10% -6%; z-index: -1; border-radius: 50%;
  background: radial-gradient(closest-side, color-mix(in srgb, var(--ac) 30%, transparent), transparent 72%);
  filter: blur(28px);
}
.device__frame {
  position: relative; aspect-ratio: 393 / 852; padding: 9px; border-radius: 46px;
  background: linear-gradient(150deg, #33363F, #14161A 42%, #0A0B0E 70%, #2B2E36);
  box-shadow:
    0 0 0 1px rgb(255 255 255 / .07) inset,
    0 2px 3px rgb(0 0 0 / .5),
    0 40px 80px -30px rgb(0 0 0 / .85);
}
.device__island {
  position: absolute; top: 20px; left: 50%; transform: translateX(-50%);
  width: 27%; height: 20px; border-radius: 999px; background: #05060A; z-index: 3;
}
.device__screen {
  position: relative; height: 100%; border-radius: 38px; overflow: hidden;
  background: var(--ac-deep);
}
.device__screen .shot {
  position: absolute; inset: 0; width: 100%; height: 100%; object-fit: cover; object-position: top center;
  opacity: 0; transition: opacity .45s var(--ease);
}
.device__screen .shot.is-on { opacity: 1; }

.shot-tabs { display: flex; flex-wrap: wrap; gap: 5px; justify-content: center; }
.shot-tabs button {
  padding: 6px 11px; border-radius: 999px; font-size: 12px; font-weight: 550;
  color: var(--mut); border: 1px solid transparent;
  transition: color .18s, background .18s, border-color .18s;
}
.shot-tabs button:hover { color: var(--ink); }
.shot-tabs button[aria-selected="true"] {
  color: var(--ac-txt); border-color: color-mix(in srgb, var(--ac) 40%, transparent);
  background: var(--ac-soft);
}

/* ── feature rows ── */
.act__flow { display: grid; gap: clamp(28px, 4vw, 44px); }
.feats { list-style: none; display: grid; gap: 2px; }
.feats li {
  display: grid; grid-template-columns: 34px 1fr; gap: 4px 14px; align-items: start;
  padding: 20px 4px; border-bottom: 1px solid var(--line);
}
.feats li:first-child { border-top: 1px solid var(--line); }
.feats__g {
  grid-row: 1 / span 2; width: 34px; height: 34px; border-radius: 9px;
  display: grid; place-items: center; font-size: 15px;
  color: var(--ac-txt); background: var(--ac-soft);
  border: 1px solid color-mix(in srgb, var(--ac) 22%, transparent);
}
.feats h3 { font-size: 17px; letter-spacing: -.02em; }
.feats p { font-size: 14.5px; color: var(--ink2); max-width: 56ch; }

/* ── demo shell ── */
.demo {
  --mx: 50%; --my: 0%;
  position: relative; padding: 24px; border-radius: var(--r-lg);
  border: 1px solid var(--line2); background: var(--card);
  box-shadow: var(--shadow); overflow: hidden;
}
.demo::before {
  content: ""; position: absolute; inset: 0; pointer-events: none; opacity: 0;
  background: radial-gradient(38ch 30ch at var(--mx) var(--my), color-mix(in srgb, var(--ac) 12%, transparent), transparent 70%);
  transition: opacity .4s var(--ease);
}
.demo:hover::before { opacity: 1; }
.demo__head { display: flex; flex-wrap: wrap; align-items: baseline; gap: 6px 14px; margin-bottom: 18px; }
.demo__title { font-size: 15px; letter-spacing: -.015em; }
.demo__title::before { content: "▸ "; color: var(--ac-txt); }
.demo__hint { font-size: 13px; color: var(--mut); }

.act__cta { display: flex; flex-wrap: wrap; align-items: center; gap: 12px; }
.badge { display: inline-flex; border-radius: 9px; transition: opacity .2s, transform .3s var(--spring); }
.badge:hover { opacity: .85; transform: translateY(-1px); }
.badge__img { height: 40px; width: auto; }

/* ═══════════  DEMO 1 — evidence ladder  ═══════════ */
.samples { display: flex; flex-wrap: wrap; gap: 6px; margin-bottom: 14px; }
.samples button {
  padding: 7px 13px; border-radius: 999px; font-size: 12.5px; font-weight: 550;
  border: 1px solid var(--line2); color: var(--ink2);
  transition: all .2s var(--ease);
}
.samples button:hover { color: var(--ink); border-color: var(--ac); }
.samples button[aria-selected="true"] {
  background: var(--ac); border-color: var(--ac); color: #08090C;
}

.filecard {
  position: relative; display: flex; align-items: center; gap: 11px;
  padding: 13px 15px; border-radius: 12px; overflow: hidden;
  background: var(--card2); border: 1px solid var(--line);
  font-size: 13px;
}
.filecard__ico {
  width: 26px; height: 26px; border-radius: 7px; flex: none;
  background: linear-gradient(140deg, var(--ac), var(--ac2));
  opacity: .9;
}
.filecard__name { font-family: var(--mono); font-size: 12.5px; color: var(--ink); }
.filecard__meta { margin-left: auto; color: var(--mut); font-size: 12px; font-variant-numeric: tabular-nums; }
.filecard__sweep {
  position: absolute; inset: 0 auto 0 -35%; width: 35%;
  background: linear-gradient(90deg, transparent, color-mix(in srgb, var(--ac) 32%, transparent), transparent);
  opacity: 0;
}
.filecard.is-scanning .filecard__sweep { opacity: 1; animation: sweep .75s var(--ease); }
@keyframes sweep { to { left: 100%; } }

.ladder { list-style: none; display: grid; gap: 1px; margin-top: 12px; }
.ladder li {
  display: grid; grid-template-columns: 26px minmax(0, 1fr) auto; align-items: center; gap: 12px;
  padding: 12px 4px; border-bottom: 1px solid var(--line);
  opacity: .32; transform: translateY(6px);
  transition: opacity .4s var(--ease), transform .4s var(--ease);
  transition-delay: calc(var(--d, 0) * 90ms);
}
.ladder.is-resolved li { opacity: 1; transform: none; }
.lad__g { font-size: 14px; color: var(--mut); text-align: center; }
.ladder.is-resolved li[data-state="found"] .lad__g { color: var(--ac-txt); }
.lad__n { display: grid; gap: 1px; min-width: 0; }
.lad__n b { font-size: 13.5px; font-weight: 600; }
.lad__n i { font-style: normal; font-size: 12px; color: var(--mut); }
.lad__v {
  font-size: 12px; font-weight: 550; padding: 4px 10px; border-radius: 999px;
  border: 1px solid var(--line2); color: var(--mut); text-align: right; white-space: nowrap;
  max-width: 24ch; overflow: hidden; text-overflow: ellipsis;
}
li[data-state="found"]  .lad__v { color: var(--ac-txt); border-color: color-mix(in srgb, var(--ac) 42%, transparent); background: var(--ac-soft); }
li[data-state="broken"] .lad__v { color: #F0A742; border-color: color-mix(in srgb, #F0A742 42%, transparent); background: color-mix(in srgb, #F0A742 12%, transparent); }
li[data-state="none"]   .lad__v,
li[data-state="off"]    .lad__v { opacity: .75; }

.verdict {
  margin-top: 16px; padding: 14px 16px; border-radius: 12px;
  border: 1px solid var(--line2); background: var(--card2);
  font-size: 13.5px; color: var(--ink2); min-height: 62px;
}
.verdict b { color: var(--ink); font-weight: 620; }
.verdict.is-null { border-color: color-mix(in srgb, var(--ac) 34%, transparent); }

/* ═══════════  DEMO 2 — A/B loop  ═══════════ */
.loop { display: grid; gap: 12px; }
.loop__wave {
  position: relative; height: 118px; border-radius: 12px; overflow: hidden;
  background: var(--card2); border: 1px solid var(--line);
  touch-action: none; cursor: ew-resize;
}
.loop__bars { position: absolute; inset: 0; width: 100%; height: 100%; }
.loop__bars rect { fill: var(--line2); transition: fill .3s; }
.loop__bars rect.in { fill: var(--ac); }
.loop__region {
  position: absolute; top: 0; bottom: 0;
  background: color-mix(in srgb, var(--ac) 11%, transparent);
  border-inline: 1px solid color-mix(in srgb, var(--ac) 55%, transparent);
  pointer-events: none;
}
.loop__head {
  position: absolute; top: 0; bottom: 0; width: 2px; background: var(--ink);
  box-shadow: 0 0 12px color-mix(in srgb, var(--ink) 60%, transparent);
  pointer-events: none;
}
.loop__handle {
  position: absolute; top: 0; bottom: 0; width: 26px; margin-left: -13px;
  display: grid; place-items: center; cursor: grab; touch-action: none; z-index: 3;
}
.loop__handle b {
  display: grid; place-items: center;
  width: 22px; height: 22px; border-radius: 7px;
  background: var(--ac); color: #08090C; font-size: 11px; font-weight: 700;
  box-shadow: 0 2px 10px rgb(0 0 0 / .45);
  transition: transform .2s var(--spring);
}
.loop__handle::after {
  content: ""; position: absolute; top: 0; bottom: 0; width: 2px; background: var(--ac);
}
.loop__handle:hover b, .loop__handle:focus-visible b { transform: scale(1.18); }
.loop__handle.is-drag { cursor: grabbing; }

.loop__scale { display: flex; justify-content: space-between; font-size: 11px; color: var(--mut); font-variant-numeric: tabular-nums; }
.loop__read {
  display: block; font-family: var(--mono); font-size: 13px; color: var(--ac-txt);
  padding: 9px 12px; border-radius: 10px; background: var(--ac-soft);
  border: 1px solid color-mix(in srgb, var(--ac) 22%, transparent);
}
.loop__ctrls { display: flex; flex-wrap: wrap; gap: 10px; align-items: center; }
.seg { display: flex; align-items: center; gap: 3px; padding: 3px; border: 1px solid var(--line); border-radius: 10px; }
.seg__lab { font-size: 11.5px; color: var(--mut); padding: 0 7px; }
.seg button {
  padding: 5px 9px; border-radius: 7px; font-size: 12px; font-weight: 550; color: var(--ink2);
  font-variant-numeric: tabular-nums; transition: all .18s;
}
.seg button:hover { color: var(--ink); background: color-mix(in srgb, var(--ink) 8%, transparent); }
.seg button.is-on { background: var(--ac); color: #08090C; }
.loop__play {
  display: inline-flex; align-items: center; gap: 8px; margin-left: auto;
  padding: 8px 15px; border-radius: 10px; border: 1px solid var(--line2);
  font-size: 12.5px; font-weight: 560;
}
.loop__play:hover { border-color: var(--ac); background: var(--ac-soft); }
.loop__play-i { width: 8px; height: 10px; background: var(--ac); clip-path: polygon(0 0,3px 0,3px 10px,0 10px,0 0,5px 0,8px 0,8px 10px,5px 10px); }
.loop__play[aria-pressed="false"] .loop__play-i { clip-path: polygon(0 0, 8px 5px, 0 10px); }
.loop__count { font-size: 12.5px; color: var(--mut); }
.loop__count b { color: var(--ink); font-variant-numeric: tabular-nums; margin-inline: 4px; }
.loop__local { color: var(--ac-txt); }

/* ═══════════  DEMO 3 — on-device chat  ═══════════ */
.chat { display: block; }
.chat__log { display: grid; gap: 10px; align-content: start; min-height: 190px; }
.bub {
  max-width: 88%; padding: 10px 14px; border-radius: 15px; font-size: 13.5px; line-height: 1.55;
  animation: bubIn .4s var(--ease) both;
}
.bub--me { justify-self: end; background: var(--ac); color: #08090C; border-bottom-right-radius: 5px; }
.bub--ai { justify-self: start; background: var(--card2); border: 1px solid var(--line); border-bottom-left-radius: 5px; }
.bub--ai .caret {
  display: inline-block; width: 2px; height: 1em; margin-left: 1px; vertical-align: -2px;
  background: var(--ac); animation: blink .9s steps(2) infinite;
}
@keyframes bubIn { from { opacity: 0; transform: translateY(8px) scale(.98); } }
@keyframes blink { 50% { opacity: 0; } }

/* ═══════════════════  WHAT THEY SHARE  ═══════════════════ */
.rule { padding: clamp(60px, 10vw, 130px) 0; border-top: 1px solid var(--line); }
.rule__title { margin: 16px 0 clamp(30px, 5vw, 56px); font-size: clamp(30px, 5vw, 56px); letter-spacing: -.035em; max-width: 18ch; }
.nevers { list-style: none; counter-reset: n; display: grid; grid-template-columns: repeat(auto-fit, minmax(258px, 1fr)); gap: 1px; background: var(--line); border: 1px solid var(--line); border-radius: var(--r-lg); overflow: hidden; }
.nevers li { counter-increment: n; padding: 26px 24px 30px; background: var(--bg); transition: background .3s; }
.nevers li:hover { background: var(--card); }
.nevers li::before {
  content: counter(n, decimal-leading-zero);
  display: block; margin-bottom: 14px;
  font-family: var(--mono); font-size: 11.5px; letter-spacing: .12em; color: var(--ac-txt);
}
.nevers h3 { font-size: 17.5px; letter-spacing: -.022em; margin-bottom: 8px; }
.nevers p { font-size: 14px; color: var(--ink2); }

.rule__foot { display: flex; flex-wrap: wrap; align-items: center; gap: 10px 20px; margin-top: 26px; font-size: 13.5px; color: var(--mut); }
.rule__links { display: flex; flex-wrap: wrap; gap: 8px; }
.rule__links a {
  padding: 6px 13px; border-radius: 999px; border: 1px solid var(--line2);
  font-size: 12.5px; color: var(--ink2); transition: all .2s;
}
.rule__links a:hover { color: var(--ac-txt); border-color: var(--ac); background: var(--ac-soft); }

/* ═══════════════════════  CLOSER  ═══════════════════════ */
.closer { padding: clamp(60px, 9vw, 120px) 0; border-top: 1px solid var(--line); text-align: center; }
.closer h2 { font-size: clamp(30px, 5vw, 54px); letter-spacing: -.035em; }
.closer__in > p { margin-top: 12px; color: var(--ink2); font-size: clamp(15px, 1.6vw, 18px); }
.closer__grid { display: grid; grid-template-columns: repeat(auto-fit, minmax(180px, 1fr)); gap: 14px; margin-top: 42px; }
.closer__card {
  --tx: 0deg; --ty: 0deg;
  display: grid; justify-items: center; gap: 9px; padding: 28px 18px;
  border: 1px solid var(--line2); border-radius: var(--r-lg); background: var(--card);
  transform: perspective(900px) rotateX(var(--tx)) rotateY(var(--ty));
  transition: transform .5s var(--ease), border-color .3s, box-shadow .3s;
}
.closer__card:hover { border-color: var(--ac); box-shadow: 0 20px 50px -24px color-mix(in srgb, var(--ac) 60%, transparent); }
.closer__card img { width: 60px; height: 60px; border-radius: 14px; }
.closer__card b { font-size: 15.5px; font-weight: 620; letter-spacing: -.02em; }
.closer__card > span { font-size: 12.5px; color: var(--mut); }

/* ═══════════════════════  FOOTER  ═══════════════════════ */
.site-foot { border-top: 1px solid var(--line); padding: clamp(40px, 6vw, 68px) 0 26px; background: var(--bg2); }
.site-foot__in { display: grid; grid-template-columns: 1.6fr repeat(4, minmax(0, 1fr)); gap: 32px 24px; }
.foot-brand { display: grid; grid-template-columns: auto 1fr; gap: 8px 9px; align-content: start; align-items: center; }
.foot-brand b { font-size: 15px; letter-spacing: -.02em; }
.foot-brand .brand__dot { grid-area: 1 / 1; }
.foot-brand p { grid-column: 1 / -1; font-size: 13px; color: var(--mut); max-width: 30ch; }
.foot-col { display: grid; gap: 7px; align-content: start; }
.foot-col h4 { font-size: 12px; letter-spacing: .08em; text-transform: uppercase; color: var(--mut); margin-bottom: 3px; font-weight: 600; }
.foot-col a, .linklike { font-size: 13px; color: var(--ink2); text-align: left; transition: color .18s; }
.linklike { padding: 0; justify-self: start; }
.foot-col a:hover, .linklike:hover { color: var(--ac-txt); }
.site-foot__bar {
  display: flex; flex-wrap: wrap; justify-content: space-between; gap: 8px;
  margin-top: clamp(32px, 5vw, 56px); padding-top: 20px; border-top: 1px solid var(--line);
  font-size: 12.5px; color: var(--mut);
}

/* ═══════════════════════  MOTION  ═══════════════════════ */
@keyframes rise { from { opacity: 0; transform: translateY(20px); } to { opacity: 1; transform: none; } }

/* preferred path: native scroll-driven timelines */
@supports (animation-timeline: view()) {
  @media (prefers-reduced-motion: no-preference) {
    .reveal, .feats li, .nevers li {
      animation: rise linear both;
      animation-timeline: view();
      animation-range: entry 4% cover 20%;
    }
  }
}
/* fallback path: IntersectionObserver adds .is-in (JS sets .js-io on <html>) */
.js-io .reveal, .js-io .feats li, .js-io .nevers li { opacity: 0; transform: translateY(20px); }
.js-io .is-in { opacity: 1; transform: none; transition: opacity .7s var(--ease), transform .7s var(--ease); }

/* ═══════════════════════  REDUCED MOTION  ═══════════════════════ */
@media (prefers-reduced-motion: reduce) {
  html { scroll-behavior: auto; }
  *, *::before, *::after {
    animation-duration: .001ms !important;
    animation-iteration-count: 1 !important;
    transition-duration: .001ms !important;
  }
  .kinetic .w > i { transform: none; }
  .band__track { animation: none; }
  .reveal, .feats li, .nevers li, .js-io .reveal, .js-io .feats li, .js-io .nevers li { opacity: 1; transform: none; }
  .ladder li { opacity: 1; transform: none; }
  .device, .closer__card { transform: none !important; }
}

/* ═══════════════════════  RESPONSIVE  ═══════════════════════ */
@media (max-width: 1080px) {
  .site-foot__in { grid-template-columns: 1fr 1fr 1fr; }
  .foot-brand { grid-column: 1 / -1; }
}

@media (max-width: 900px) {
  html { scroll-padding-top: 76px; }
  .hero__in { grid-template-columns: 1fr; }
  .hero__art { order: -1; }
  #boundary { width: min(78%, 340px); }
  .act__body { grid-template-columns: 1fr; }
  .act__stage { position: static; }
  .device { width: min(72%, 268px); }
  .act__head { grid-template-columns: auto 1fr; row-gap: 14px; }
  .act__num { grid-column: 1; }
  .act__id { grid-column: 2; }
  .chips { grid-column: 1 / -1; justify-self: start; }
}

@media (max-width: 640px) {
  .site-nav { display: none; }
  .head-tools { margin-left: auto; }
  .hero__stats { gap: 14px 22px; }
  .hero__stats b { font-size: 23px; }
  .demo { padding: 18px 15px; }
  .ladder li { grid-template-columns: 22px minmax(0, 1fr); row-gap: 6px; }
  .lad__v { grid-column: 2; justify-self: start; text-align: left; max-width: none; }
  .loop__ctrls { flex-direction: column; align-items: stretch; }
  .loop__play { margin-left: 0; justify-content: center; }
  .seg { justify-content: space-between; }
  .site-foot__in { grid-template-columns: 1fr 1fr; }
  .site-foot__bar { flex-direction: column; }
}

/* coarse pointers: no tilt, no magnets */
@media (hover: none) {
  .device, .closer__card { transform: none !important; }
  .btn { transform: none !important; }
}