/* ==========================================================
   宇奇引擎 · Yuqi Engine — Official Site
   视觉关键词：安静 · 精确 · 透明
   ========================================================== */

:root {
  --bg: #f6f8f8;
  --bg-2: #eef3f2;
  --card: #ffffff;
  --ink: #0e1414;
  --ink-2: #3c4949;
  --ink-3: #6b7a7a;
  --ink-4: #98a5a5;
  --line: #e2e9e8;
  --line-2: #d3dddc;
  --grid: rgba(18, 122, 110, 0.07);

  --brand: #127a6e;
  --brand-ink: #0c5d54;
  --brand-soft: #e5f2f0;
  --brand-glow: rgba(18, 122, 110, 0.18);

  --ok: #1f9d55;
  --ok-soft: #e6f5ec;
  --warn: #c97d12;
  --warn-soft: #fbf1e1;
  --bad: #d14343;
  --bad-soft: #fbeaea;
  --na: #8f9b9b;
  --na-soft: #eff2f2;

  --font-sans: -apple-system, BlinkMacSystemFont, "Segoe UI Variable Text", "Segoe UI", "Inter",
    "PingFang SC", "HarmonyOS Sans SC", "MiSans", "Hiragino Sans GB", "Microsoft YaHei UI",
    "Microsoft YaHei", system-ui, sans-serif;
  --font-mono: "JetBrains Mono", "Cascadia Mono", "Cascadia Code", "SF Mono", Consolas, "Liberation Mono",
    monospace;

  --r-sm: 8px;
  --r-md: 14px;
  --r-lg: 22px;
  --r-xl: 30px;

  --shadow-1: 0 1px 2px rgba(14, 20, 20, 0.04), 0 2px 8px rgba(14, 20, 20, 0.04);
  --shadow-2: 0 2px 6px rgba(14, 20, 20, 0.04), 0 12px 32px rgba(14, 20, 20, 0.07);
  --shadow-3: 0 4px 12px rgba(14, 20, 20, 0.05), 0 30px 80px -20px rgba(14, 40, 38, 0.28);

  --ease: cubic-bezier(0.22, 1, 0.36, 1);
  --wrap: 1180px;
  --nav-h: 64px;
}

/* ---------- base ---------- */
*,
*::before,
*::after {
  box-sizing: border-box;
}
html {
  -webkit-text-size-adjust: 100%;
  scroll-behavior: smooth;
  scroll-padding-top: calc(var(--nav-h) + 16px);
}
body {
  margin: 0;
  background: var(--bg);
  color: var(--ink);
  font-family: var(--font-sans);
  font-size: 17px;
  line-height: 1.65;
  -webkit-font-smoothing: antialiased;
  -moz-osx-font-smoothing: grayscale;
  text-rendering: optimizeLegibility;
  overflow-x: hidden;
}
img {
  max-width: 100%;
  display: block;
}
a {
  color: inherit;
  text-decoration: none;
}
button {
  font: inherit;
  color: inherit;
  background: none;
  border: 0;
  cursor: pointer;
  padding: 0;
}
h1,
h2,
h3,
h4,
p {
  margin: 0;
}
::selection {
  background: var(--brand);
  color: #fff;
}
:focus-visible {
  outline: 2px solid var(--brand);
  outline-offset: 3px;
  border-radius: 6px;
}
.mono {
  font-family: var(--font-mono);
  font-feature-settings: "zero" 1;
  letter-spacing: 0;
}
.wrap {
  width: min(var(--wrap), 100% - 48px);
  margin-inline: auto;
}
.sr-only {
  position: absolute;
  width: 1px;
  height: 1px;
  overflow: hidden;
  clip: rect(0 0 0 0);
  white-space: nowrap;
}
.icon {
  width: 20px;
  height: 20px;
  flex: none;
  stroke: currentColor;
  fill: none;
  stroke-width: 1.6;
  stroke-linecap: round;
  stroke-linejoin: round;
}
.icon.fill {
  fill: currentColor;
  stroke: none;
}

/* ---------- language ---------- */
html[data-lang="zh"] .en,
html[data-lang="en"] .zh {
  display: none !important;
}
html[data-lang="en"] body {
  letter-spacing: -0.005em;
}

/* ---------- nav ---------- */
.nav {
  position: sticky;
  top: 0;
  z-index: 50;
  height: var(--nav-h);
  transition: background 0.3s var(--ease), box-shadow 0.3s var(--ease);
}
.nav.scrolled {
  background: rgba(246, 248, 248, 0.78);
  backdrop-filter: saturate(160%) blur(16px);
  -webkit-backdrop-filter: saturate(160%) blur(16px);
  box-shadow: 0 1px 0 var(--line);
}
.nav-inner {
  height: 100%;
  display: flex;
  align-items: center;
  gap: 28px;
}
.brand {
  display: flex;
  align-items: center;
  gap: 10px;
  font-weight: 650;
  font-size: 16px;
  letter-spacing: 0.01em;
  white-space: nowrap;
}
.brand img {
  width: 26px;
  height: auto;
}
.brand small {
  font-weight: 500;
  color: var(--ink-3);
  font-size: 15px;
}
.nav-links {
  display: flex;
  gap: 4px;
  margin-left: 8px;
}
.nav-links a {
  font-size: 14.5px;
  color: var(--ink-2);
  padding: 7px 12px;
  border-radius: 8px;
  transition: color 0.2s, background 0.2s;
}
.nav-links a:hover {
  color: var(--ink);
  background: rgba(14, 20, 20, 0.045);
}
.nav-links a.active {
  color: var(--ink);
  font-weight: 600;
}
.nav-right {
  margin-left: auto;
  display: flex;
  align-items: center;
  gap: 8px;
}
.icon-btn {
  width: 38px;
  height: 38px;
  display: grid;
  place-items: center;
  border-radius: 10px;
  color: var(--ink-2);
  transition: background 0.2s, color 0.2s;
}
.icon-btn:hover {
  background: rgba(14, 20, 20, 0.05);
  color: var(--ink);
}
.lang-toggle {
  display: flex;
  align-items: center;
  height: 34px;
  padding: 3px;
  border-radius: 999px;
  background: rgba(14, 20, 20, 0.05);
  font-size: 12.5px;
  font-weight: 600;
}
.lang-toggle button {
  height: 28px;
  padding: 0 11px;
  border-radius: 999px;
  color: var(--ink-3);
  transition: all 0.25s var(--ease);
}
html[data-lang="zh"] .lang-toggle [data-set-lang="zh"],
html[data-lang="en"] .lang-toggle [data-set-lang="en"] {
  background: #fff;
  color: var(--ink);
  box-shadow: var(--shadow-1);
}
.nav-cta {
  margin-left: 4px;
}
.menu-btn {
  display: none;
}
.mobile-menu {
  display: none;
}

/* ---------- buttons ---------- */
.btn {
  --h: 46px;
  display: inline-flex;
  align-items: center;
  justify-content: center;
  gap: 9px;
  height: var(--h);
  padding: 0 22px;
  border-radius: 999px;
  font-size: 15.5px;
  font-weight: 600;
  white-space: nowrap;
  transition: transform 0.25s var(--ease), box-shadow 0.25s var(--ease), background 0.25s, color 0.25s,
    border-color 0.25s;
  position: relative;
  isolation: isolate;
}
.btn .icon {
  width: 18px;
  height: 18px;
}
.btn-primary {
  background: var(--ink);
  color: #fff;
  box-shadow: 0 1px 0 rgba(255, 255, 255, 0.12) inset, 0 6px 18px -6px rgba(14, 20, 20, 0.45);
  overflow: hidden;
}
.btn-primary::after {
  content: "";
  position: absolute;
  inset: 0;
  background: linear-gradient(110deg, transparent 30%, rgba(255, 255, 255, 0.18) 50%, transparent 70%);
  transform: translateX(-120%);
  transition: transform 0.8s var(--ease);
  z-index: -1;
}
.btn-primary:hover {
  transform: translateY(-1px);
  box-shadow: 0 1px 0 rgba(255, 255, 255, 0.12) inset, 0 12px 28px -8px rgba(14, 20, 20, 0.5);
}
.btn-primary:hover::after {
  transform: translateX(120%);
}
.btn-brand {
  background: var(--brand);
  color: #fff;
  box-shadow: 0 8px 22px -8px var(--brand-glow);
}
.btn-brand:hover {
  background: var(--brand-ink);
  transform: translateY(-1px);
}
.btn-ghost {
  background: rgba(255, 255, 255, 0.7);
  color: var(--ink);
  border: 1px solid var(--line-2);
}
.btn-ghost:hover {
  border-color: var(--ink-4);
  background: #fff;
  transform: translateY(-1px);
}
.btn-sm {
  --h: 36px;
  padding: 0 15px;
  font-size: 14px;
}
.btn .arrow {
  transition: transform 0.25s var(--ease);
}
.btn:hover .arrow {
  transform: translateX(3px);
}
.btn:active {
  transform: translateY(0) scale(0.97);
  transition-duration: 0.08s;
}

/* ---------- typographic refinement ---------- */
.hero-title,
.page-hero .h1,
html[data-lang="en"] .h2 {
  text-wrap: balance;
}
html[data-lang="zh"] .h2 {
  text-wrap: pretty;
}
.lead {
  text-wrap: pretty;
}
html[data-lang="zh"] .hero-title,
html[data-lang="zh"] .page-hero .h1,
html[data-lang="zh"] .h2,
html[data-lang="zh"] .block-title h2,
html[data-lang="zh"] .tl-item h3 {
  font-feature-settings: "halt"; /* 中文标点挤压，收紧逗号句号占位 */
}
.hero-meta,
.ver-date,
.file-btn .size,
.tl-date,
.tl-item .tl-date,
.req {
  font-variant-numeric: tabular-nums;
}

/* ---------- subtle grain (material texture, kills flatness) ---------- */
body::before {
  content: "";
  position: fixed;
  inset: 0;
  z-index: 4000;
  pointer-events: none;
  background-image: url("data:image/svg+xml,%3Csvg viewBox='0 0 200 200' xmlns='http://www.w3.org/2000/svg'%3E%3Cfilter id='n'%3E%3CfeTurbulence type='fractalNoise' baseFrequency='0.9' numOctaves='3' stitchTiles='stitch'/%3E%3C/filter%3E%3Crect width='100%25' height='100%25' filter='url(%23n)' opacity='0.028'/%3E%3C/svg%3E");
}

/* ---------- section scaffolding ---------- */
.section {
  padding: clamp(96px, 13vw, 168px) 0;
  position: relative;
}
.section.flush-top {
  padding-top: 0;
}
.section.flush-bottom {
  padding-bottom: clamp(64px, 9vw, 120px);
}
.section-head {
  max-width: 760px;
  margin-bottom: clamp(48px, 6vw, 72px);
}
html[data-lang="zh"] .section-head {
  max-width: 960px;
}
html[data-lang="zh"] .section-head .lead {
  max-width: 820px;
}
.section-head.center {
  margin-inline: auto;
  text-align: center;
}
html[data-lang="zh"] .section-head.center .lead {
  margin-inline: auto;
}
.kicker {
  display: inline-flex;
  align-items: center;
  gap: 10px;
  font-size: 13px;
  font-weight: 600;
  letter-spacing: 0.14em;
  text-transform: uppercase;
  color: var(--brand);
  margin-bottom: 20px;
}
.kicker .ymark {
  width: 15px;
  height: 15px;
}
.h2 {
  font-size: clamp(34px, 4.6vw, 54px);
  line-height: 1.12;
  letter-spacing: -0.025em;
  font-weight: 700;
}
html[data-lang="zh"] .h2 {
  letter-spacing: -0.01em;
  line-height: 1.2;
}
@media (min-width: 761px) {
  .mbr {
    display: none;
  }
}
.em {
  font-style: normal;
  color: var(--brand);
}
.lead {
  margin-top: 22px;
  font-size: clamp(17px, 1.5vw, 19.5px);
  color: var(--ink-3);
  line-height: 1.7;
}
.muted {
  color: var(--ink-3);
}

/* Y mark (logo motif) */
.ymark {
  stroke: currentColor;
  fill: none;
  stroke-width: 2.2;
  stroke-linecap: round;
}

/* grid background */
.grid-bg {
  position: absolute;
  inset: 0;
  pointer-events: none;
  background-image: linear-gradient(var(--grid) 1px, transparent 1px),
    linear-gradient(90deg, var(--grid) 1px, transparent 1px);
  background-size: 44px 44px;
  background-position: center top;
}

/* reveal */
.reveal {
  opacity: 0;
  transform: translateY(26px);
  transition: opacity 0.9s var(--ease), transform 0.9s var(--ease);
  transition-delay: var(--d, 0ms);
}
.reveal.in {
  opacity: 1;
  transform: none;
}

/* ==========================================================
   HERO
   ========================================================== */
.hero {
  position: relative;
  padding: clamp(56px, 8vw, 96px) 0 0;
  margin-top: calc(var(--nav-h) * -1);
  padding-top: calc(var(--nav-h) + clamp(40px, 5.5vw, 76px));
  overflow: hidden;
}
.hero .grid-bg {
  -webkit-mask-image: radial-gradient(ellipse 70% 60% at 50% 72%, #000 20%, transparent 75%);
  mask-image: radial-gradient(ellipse 70% 60% at 50% 72%, #000 20%, transparent 75%);
}
.hero-glow {
  position: absolute;
  left: 50%;
  top: 55%;
  width: min(1100px, 120vw);
  aspect-ratio: 2 / 1;
  transform: translate(-50%, -50%);
  background: radial-gradient(ellipse 65% 55% at 50% 50%, rgba(20, 184, 166, 0.16) 0%, rgba(20, 184, 166, 0.04) 50%, transparent 72%);
  pointer-events: none;
}
.hero-copy {
  position: relative;
  text-align: center;
  max-width: 1080px;
  margin-inline: auto;
}
.pill {
  display: inline-flex;
  align-items: center;
  gap: 10px;
  height: 34px;
  padding: 0 6px 0 14px;
  border-radius: 999px;
  background: rgba(255, 255, 255, 0.75);
  border: 1px solid var(--line);
  box-shadow: var(--shadow-1);
  font-size: 13.5px;
  color: var(--ink-2);
  transition: border-color 0.25s, transform 0.25s var(--ease);
}
.pill:hover {
  border-color: var(--line-2);
  transform: translateY(-1px);
}
.pill .dot {
  width: 7px;
  height: 7px;
  border-radius: 50%;
  background: var(--ok);
  box-shadow: 0 0 0 3px var(--ok-soft);
}
.pill .tag {
  height: 24px;
  display: inline-flex;
  align-items: center;
  gap: 4px;
  padding: 0 10px;
  border-radius: 999px;
  background: var(--bg-2);
  font-weight: 600;
  color: var(--ink);
  font-size: 12.5px;
}
.hero-title {
  margin-top: 30px;
  font-size: clamp(42px, 7vw, 86px);
  line-height: 1.06;
  letter-spacing: -0.035em;
  font-weight: 760;
}
html[data-lang="zh"] .hero-title {
  letter-spacing: -0.015em;
  line-height: 1.16;
  font-size: clamp(34px, 5vw, 66px);
}
.hero-title .line {
  display: block;
  overflow: hidden;
  padding-bottom: 0.06em;
  white-space: nowrap;
}
.hero-title .line > span {
  display: inline-block;
  transform: translateY(105%);
  animation: lineUp 1.1s var(--ease) forwards;
  animation-delay: var(--d, 0ms);
}
.hero-title .accent {
  color: var(--brand);
  position: relative;
}
@keyframes lineUp {
  to {
    transform: none;
  }
}
.hero-sub {
  margin: 26px auto 0;
  max-width: 680px;
  font-size: clamp(17px, 1.6vw, 20px);
  color: var(--ink-3);
  line-height: 1.7;
}
.hero-ctas {
  margin-top: 38px;
  display: flex;
  justify-content: center;
  gap: 12px;
  flex-wrap: wrap;
}
.hero-meta {
  margin-top: 30px;
  display: flex;
  justify-content: center;
  flex-wrap: wrap;
  font-size: 13.5px;
  color: var(--ink-3);
}
.hero-meta > span {
  display: inline-flex;
  align-items: center;
  gap: 7px;
  padding: 6px 0;
}
.hero-meta > span + span {
  margin-left: 24px;
  position: relative;
}
.hero-meta > span + span::before {
  content: "";
  position: absolute;
  left: -12px;
  top: 50%;
  width: 1px;
  height: 12px;
  transform: translateY(-50%);
  background: var(--line-2);
}
.hero-meta .icon {
  width: 15px;
  height: 15px;
  color: var(--brand);
}
.fade-up {
  opacity: 0;
  transform: translateY(16px);
  animation: fadeUp 1s var(--ease) forwards;
  animation-delay: var(--d, 0ms);
}
@keyframes fadeUp {
  to {
    opacity: 1;
    transform: none;
  }
}

/* hero shot */
.hero-stage {
  position: relative;
  margin-top: clamp(44px, 5vw, 64px);
  padding-bottom: clamp(40px, 6vw, 72px);
}
.window {
  position: relative;
  border-radius: 14px;
  background: #fff;
  box-shadow: 0 0 0 1px rgba(14, 20, 20, 0.08), 0 16px 40px -8px rgba(14, 20, 20, 0.09), 0 32px 64px -16px rgba(14, 20, 20, 0.12);
  overflow: hidden;
}
.window img {
  width: 100%;
  height: auto;
}
.hero-window {
  max-width: 1080px;
  margin-inline: auto;
  opacity: 0;
  animation: heroWindowIn 1s var(--ease) forwards;
  animation-delay: 500ms;
}
@keyframes heroWindowIn {
  from {
    opacity: 0;
    transform: translateY(22px);
  }
  to {
    opacity: 1;
    transform: none;
  }
}
.hero-window::after {
  content: "";
  position: absolute;
  inset: 0;
  border-radius: inherit;
  background: linear-gradient(180deg, rgba(255, 255, 255, 0.0) 60%, rgba(246, 248, 248, 0.0));
  pointer-events: none;
}
.hero-reflect {
  position: absolute;
  left: 50%;
  bottom: 0;
  width: min(900px, 80%);
  height: 50px;
  transform: translateX(-50%);
  background: radial-gradient(ellipse 60% 50% at 50% 50%, rgba(14, 40, 38, 0.12), transparent 70%);
  z-index: -1;
  pointer-events: none;
}
.shot-note {
  margin-top: 18px;
  text-align: center;
  font-size: 12.5px;
  color: var(--ink-4);
}
.shot-note a {
  color: var(--brand);
  font-weight: 550;
  text-decoration: underline;
  text-underline-offset: 3px;
}

/* floating chips on hero */
.float-chip {
  position: absolute;
  z-index: 3;
  display: flex;
  align-items: center;
  gap: 10px;
  padding: 10px 14px;
  border-radius: 14px;
  background: rgba(255, 255, 255, 0.96);
  border: 1px solid var(--line);
  box-shadow: var(--shadow-2);
  font-size: 13px;
  color: var(--ink-2);
  white-space: nowrap;
  pointer-events: none;
  opacity: 0;
  animation: chipIn 1s var(--ease) forwards, bob 6s ease-in-out infinite;
  animation-delay: var(--d), calc(var(--d) + 1s);
}
.float-chip b {
  color: var(--ink);
  font-weight: 650;
}
.float-chip .badge {
  width: 30px;
  height: 30px;
  border-radius: 9px;
  display: grid;
  place-items: center;
}
.float-chip .badge .icon {
  width: 17px;
  height: 17px;
}
.chip-a {
  left: max(0px, calc(50% - 600px));
  top: 18%;
}
.chip-b {
  right: max(0px, calc(50% - 600px));
  top: 46%;
}
@keyframes chipIn {
  from {
    opacity: 0;
    transform: translateY(14px) scale(0.96);
  }
  to {
    opacity: 1;
    transform: none;
  }
}
@keyframes bob {
  0%,
  100% {
    translate: 0 var(--py, 0px);
  }
  50% {
    translate: 0 calc(var(--py, 0px) - 6px);
  }
}

/* hero parallax layers — JS drives --py per layer */
.hero .grid-bg {
  translate: 0 var(--py, 0px);
}

/* ==========================================================
   WHAT IT DOES (3 cards with crafted mini UIs)
   ========================================================== */
.what-grid {
  display: grid;
  grid-template-columns: repeat(3, 1fr);
  gap: 20px;
}
.card {
  background: var(--card);
  border: 1px solid var(--line);
  border-radius: var(--r-lg);
  box-shadow: var(--shadow-1);
}
.what-card {
  padding: 30px 30px 0;
  display: flex;
  flex-direction: column;
  overflow: hidden;
  transition: transform 0.5s var(--ease), box-shadow 0.5s var(--ease), border-color 0.4s;
}
.what-card:hover {
  transform: translateY(-4px);
  box-shadow: var(--shadow-2);
  border-color: var(--line-2);
}
.what-card .num {
  font-family: var(--font-mono);
  font-size: 13px;
  color: var(--brand);
  letter-spacing: 0.05em;
}
.what-card h3 {
  margin-top: 14px;
  font-size: 23px;
  letter-spacing: -0.01em;
  font-weight: 680;
}
.what-card p {
  margin-top: 10px;
  color: var(--ink-3);
  font-size: 15.5px;
  line-height: 1.7;
  min-height: 3.4em;
}
html[data-lang="en"] .what-card p {
  min-height: 5.1em;
}
.mini {
  margin-top: auto;
  padding-top: 16px;
  flex: 1;
  min-height: 230px;
  position: relative;
  border-radius: 14px 14px 0 0;
  background: var(--bg);
  border: 1px solid var(--line);
  border-bottom: 0;
  padding: 16px;
  font-size: 12.5px;
  overflow: hidden;
}
.mini::after {
  content: "";
  position: absolute;
  inset: auto 0 0 0;
  height: 48px;
  background: linear-gradient(transparent, var(--card));
  pointer-events: none;
}
/* mini: modules list */
.mini-list {
  display: grid;
  gap: 4px;
}
.mini-row {
  display: flex;
  align-items: center;
  gap: 10px;
  padding: 8px 10px;
  border-radius: 9px;
  color: var(--ink-2);
  transition: background 0.3s, color 0.3s;
}
.mini-row .icon {
  width: 16px;
  height: 16px;
  color: var(--ink-3);
}
.mini-row .count {
  margin-left: auto;
  font-family: var(--font-mono);
  font-size: 11.5px;
  color: var(--ink-4);
}
.mini-row.on {
  background: #fff;
  color: var(--ink);
  box-shadow: var(--shadow-1);
  font-weight: 600;
}
.mini-row.on .icon {
  color: var(--brand);
}
.what-card:hover .mini-row:nth-child(3) {
  background: #fff;
  box-shadow: var(--shadow-1);
}
/* mini: detail panel */
.mini-detail {
  background: #fff;
  border: 1px solid var(--line);
  border-radius: 12px;
  padding: 14px;
  box-shadow: var(--shadow-1);
}
.mini-detail .t {
  display: flex;
  align-items: center;
  gap: 8px;
  font-weight: 650;
  font-size: 13.5px;
  color: var(--ink);
}
.mini-detail dl {
  margin: 12px 0 0;
  display: grid;
  grid-template-columns: auto 1fr;
  gap: 8px 12px;
}
.mini-detail dt {
  color: var(--ink-4);
}
.mini-detail dd {
  margin: 0;
  color: var(--ink-2);
}
.mini-detail .tags {
  display: flex;
  gap: 6px;
  margin-top: 12px;
  flex-wrap: wrap;
}
/* mini: backup timeline */
.mini-tl {
  position: relative;
  padding-left: 22px;
  display: grid;
  gap: 16px;
}
.mini-tl::before {
  content: "";
  position: absolute;
  left: 6px;
  top: 6px;
  bottom: 6px;
  width: 1.5px;
  background: var(--line-2);
}
.mini-tl .step {
  position: relative;
  background: #fff;
  border: 1px solid var(--line);
  border-radius: 10px;
  padding: 10px 12px;
  box-shadow: var(--shadow-1);
}
.mini-tl .step::before {
  content: "";
  position: absolute;
  left: -21px;
  top: 14px;
  width: 11px;
  height: 11px;
  border-radius: 50%;
  background: #fff;
  border: 2px solid var(--ink-4);
}
.mini-tl .step.done::before {
  border-color: var(--ok);
  background: var(--ok);
  box-shadow: 0 0 0 3px var(--ok-soft);
}
.mini-tl .step b {
  display: block;
  color: var(--ink);
  font-weight: 620;
  font-size: 12.5px;
}
.mini-tl .step > span {
  color: var(--ink-4);
  font-size: 11.5px;
}

/* status chip (shared with demo) */
.st {
  display: inline-flex;
  align-items: center;
  gap: 6px;
  height: 24px;
  padding: 0 9px;
  border-radius: 999px;
  font-size: 12px;
  font-weight: 600;
  white-space: nowrap;
  transition: background 0.4s var(--ease), color 0.4s var(--ease), box-shadow 0.3s;
}
.st i {
  width: 6px;
  height: 6px;
  border-radius: 50%;
  background: currentColor;
  flex: none;
}
.st-ok {
  background: var(--ok-soft);
  color: var(--ok);
}
.st-warn {
  background: var(--warn-soft);
  color: var(--warn);
}
.st-bad {
  background: var(--bad-soft);
  color: var(--bad);
}
.st-na {
  background: var(--na-soft);
  color: var(--na);
}
.st-read {
  background: var(--brand-soft);
  color: var(--brand);
}
.st-read i {
  background: transparent;
  width: 10px;
  height: 10px;
  border: 1.6px solid currentColor;
  border-right-color: transparent;
  animation: spin 0.8s linear infinite;
}
@keyframes spin {
  to {
    transform: rotate(360deg);
  }
}

/* ==========================================================
   FLOW
   ========================================================== */
.flow-section {
  background: linear-gradient(180deg, var(--bg), #fff 40%, #fff 60%, var(--bg));
}
/* pinned narrative: sticky stage, scroll scrubs steps */
.flow-pin {
  position: relative;
  height: 440vh;
}
.flow-sticky {
  position: sticky;
  top: 0;
  min-height: 100vh;
  display: flex;
  flex-direction: column;
  justify-content: center;
  padding: calc(var(--nav-h) + 20px) 0 28px;
}
.flow-cols {
  display: grid;
  grid-template-columns: minmax(0, 0.85fr) minmax(0, 1.15fr);
  gap: clamp(44px, 6vw, 96px);
  align-items: center;
  margin-top: clamp(24px, 3.5vh, 44px);
}
.flow-steps {
  list-style: none;
  margin: 0;
  padding: 0;
}
.fstep {
  position: relative;
  padding: 14px 0 14px 62px;
  opacity: 0.34;
  transition: opacity 0.5s var(--ease);
}
.fstep::before {
  content: "";
  position: absolute;
  left: 20px;
  top: 58px;
  bottom: -16px;
  width: 2px;
  background: var(--line);
}
.fstep:last-child::before {
  display: none;
}
.fstep.lit {
  opacity: 1;
}
.flow-node {
  width: 56px;
  height: 56px;
  margin: 0 auto;
  border-radius: 50%;
  background: #fff;
  border: 1px solid var(--line-2);
  display: grid;
  place-items: center;
  color: var(--ink-4);
  position: relative;
  transition: all 0.6s var(--ease);
}
.fstep .flow-node {
  position: absolute;
  left: 0;
  top: 14px;
  margin: 0;
  width: 42px;
  height: 42px;
  background: var(--bg);
}
.flow-node .icon {
  width: 22px;
  height: 22px;
}
.fstep .flow-node .icon {
  width: 18px;
  height: 18px;
}
.fstep.lit .flow-node {
  color: var(--brand);
  border-color: rgba(18, 122, 110, 0.4);
  background: var(--brand-soft);
}
.fstep.on .flow-node {
  color: #fff;
  background: var(--brand);
  border-color: var(--brand);
  box-shadow: 0 0 0 6px var(--brand-soft), 0 10px 24px -8px var(--brand-glow);
}
.fstep .idx {
  font-family: var(--font-mono);
  font-size: 12px;
  color: var(--brand);
  letter-spacing: 0.08em;
}
.fstep h3 {
  margin-top: 4px;
  font-size: 19px;
  font-weight: 680;
}
.fstep p {
  margin-top: 6px;
  font-size: 14.5px;
  color: var(--ink-3);
  line-height: 1.65;
  max-width: 42ch;
}

/* right-hand visual panels, crossfaded by scroll */
.flow-stage {
  position: relative;
  min-height: clamp(340px, 46vh, 460px);
}
.fvis {
  position: absolute;
  inset: 0;
  display: flex;
  align-items: center;
  justify-content: center;
  opacity: 0;
  transform: translateY(26px) scale(0.975);
  transition: opacity 0.55s var(--ease), transform 0.55s var(--ease);
  pointer-events: none;
}
.fvis.on {
  opacity: 1;
  transform: none;
  pointer-events: auto;
}
.fvis-card {
  width: min(440px, 100%);
  padding: 24px 26px;
}

/* scroll progress bar under the columns */
.flow-bar {
  margin-top: clamp(26px, 4vh, 46px);
  height: 2px;
  border-radius: 2px;
  background: var(--line);
  overflow: hidden;
}
.flow-bar i {
  display: block;
  height: 100%;
  background: linear-gradient(90deg, var(--brand), #2bb3a2);
  transform: scaleX(var(--fp, 0));
  transform-origin: left;
}

/* terminal — step 1 visual */
.term {
  width: min(540px, 100%);
  border-radius: 16px;
  overflow: hidden;
  background: #0c1417;
  box-shadow: var(--shadow-3), 0 0 0 1px rgba(255, 255, 255, 0.07);
  font-family: var(--font-mono);
}
.term-bar {
  display: flex;
  align-items: center;
  gap: 6px;
  padding: 11px 15px;
  border-bottom: 1px solid rgba(255, 255, 255, 0.07);
}
.term-bar i {
  width: 9px;
  height: 9px;
  border-radius: 50%;
  background: rgba(255, 255, 255, 0.15);
}
.term-bar span {
  margin-left: auto;
  font-size: 11px;
  letter-spacing: 0.1em;
  color: rgba(255, 255, 255, 0.35);
}
.term-body {
  padding: 18px 20px 22px;
  min-height: 240px;
  font-size: 12.8px;
  line-height: 1.5;
  color: #b9c8c5;
}
.term-body p {
  display: flex;
  align-items: baseline;
  gap: 8px;
  margin: 0 0 10px;
  opacity: 0;
  transform: translateY(5px);
  transition: opacity 0.35s, transform 0.35s var(--ease);
}
.term-body p.on {
  opacity: 1;
  transform: none;
}
.term .t-c {
  color: #2bd4c0;
}
.term .t-mut {
  color: rgba(255, 255, 255, 0.38);
}
.term .t-warn {
  color: #f5b04c;
}
.term b {
  color: #e8f2f0;
  font-weight: 600;
}
.term .t-d {
  width: 7px;
  height: 7px;
  border-radius: 50%;
  flex: none;
  position: relative;
  top: -1px;
}
.term .t-d.ok {
  background: #34d399;
}
.term .t-d.warn {
  background: #f5b04c;
}
.term .t-d.na {
  background: #5e6a77;
}
.term .t-caret {
  display: inline-block;
  width: 8px;
  height: 14px;
  background: #2bd4c0;
  vertical-align: -2px;
  animation: caretBlink 1s steps(1) infinite;
}
@keyframes caretBlink {
  50% {
    opacity: 0;
  }
}

/* step 3: pick list · step 4: verify sequence */
.pick {
  display: grid;
  gap: 8px;
}
.pick-row {
  display: flex;
  align-items: center;
  gap: 11px;
  padding: 11px 13px;
  border-radius: 11px;
  border: 1px solid var(--line);
  font-size: 14px;
  color: var(--ink-2);
}
.pick-row.on {
  border-color: rgba(18, 122, 110, 0.3);
  background: var(--brand-soft);
  color: var(--ink);
}
.pick-row.locked {
  color: var(--ink-4);
}
.pick .ck {
  width: 18px;
  height: 18px;
  flex: none;
  border-radius: 5px;
  border: 1.5px solid var(--line-2);
  display: grid;
  place-items: center;
  color: transparent;
}
.pick-row.on .ck {
  background: var(--brand);
  border-color: var(--brand);
  color: #fff;
}
.pick-row.locked .ck {
  border-color: var(--line-2);
  color: var(--ink-4);
}
.pick .ck .icon {
  width: 12px;
  height: 12px;
}
.seq {
  display: grid;
  gap: 10px;
}
.seq-row {
  display: flex;
  align-items: center;
  gap: 12px;
  padding: 11px 14px;
  border-radius: 11px;
  border: 1px solid var(--line);
}
.seq-mut {
  font-size: 12.5px;
  color: var(--ink-4);
}
.seq-arrow {
  display: grid;
  place-items: center;
  color: var(--ink-4);
}
.seq-arrow .icon {
  width: 15px;
  height: 15px;
  transform: rotate(90deg);
}
.seq-note {
  margin: 8px 0 0;
  font-size: 13px;
  line-height: 1.65;
  color: var(--ink-3);
  border-top: 1px dashed var(--line);
  padding-top: 12px;
}
.promise {
  margin: clamp(56px, 7vw, 84px) auto 0;
  max-width: 760px;
  text-align: center;
  padding: 26px 30px;
  border-radius: var(--r-lg);
  border: 1px dashed var(--line-2);
  background: rgba(255, 255, 255, 0.6);
  font-size: clamp(18px, 2vw, 22px);
  font-weight: 620;
  letter-spacing: -0.01em;
}
.promise .icon {
  display: inline-block;
  vertical-align: -3px;
  width: 22px;
  height: 22px;
  color: var(--ok);
  margin-right: 8px;
}

/* ==========================================================
   STATUS DEMO
   ========================================================== */
.status-wrap {
  display: grid;
  grid-template-columns: 0.9fr 1.1fr;
  gap: clamp(40px, 6vw, 88px);
  align-items: center;
}
.legend {
  margin-top: 36px;
  display: grid;
  gap: 2px;
}
.legend-row {
  display: grid;
  grid-template-columns: minmax(88px, max-content) 1fr;
  gap: 16px;
  align-items: baseline;
  padding: 12px 0;
  border-top: 1px solid var(--line);
  font-size: 15px;
  color: var(--ink-3);
  transition: color 0.3s;
}
.legend-row.hl {
  color: var(--ink);
}
.legend-row.hl .st {
  box-shadow: 0 0 0 4px var(--brand-soft);
}
.legend-row:last-child {
  border-bottom: 1px solid var(--line);
}
/* hovering a legend row dims the demo to items of that state */
.status-demo[data-focus] .demo-item {
  opacity: 0.36;
}
.status-demo[data-focus="ok"] .demo-item[data-state="ok"],
.status-demo[data-focus="read"] .demo-item[data-state="read"],
.status-demo[data-focus="warn"] .demo-item[data-state="warn"],
.status-demo[data-focus="na"] .demo-item[data-state="na"] {
  opacity: 1;
  border-left-color: var(--brand);
  background: linear-gradient(90deg, rgba(18, 122, 110, 0.06), transparent 70%);
}
.panel {
  position: relative;
  background: #fff;
  border: 1px solid var(--line);
  border-radius: var(--r-lg);
  box-shadow: var(--shadow-3);
  overflow: visible;
}
.panel-head {
  display: flex;
  align-items: center;
  gap: 12px;
  padding: 18px 22px;
  border-bottom: 1px solid var(--line);
}
.panel-head .ic {
  width: 36px;
  height: 36px;
  border-radius: 10px;
  background: var(--bg);
  border: 1px solid var(--line);
  display: grid;
  place-items: center;
  color: var(--ink-2);
}
.panel-head b {
  display: block;
  font-size: 15.5px;
  font-weight: 650;
}
.panel-head > div > span {
  display: block;
  font-size: 12.5px;
  color: var(--ink-4);
}
.panel-head .replay {
  margin-left: auto;
}
.demo-list {
  padding: 6px 0;
}
.demo-item {
  display: grid;
  grid-template-columns: 1fr auto;
  align-items: center;
  gap: 16px;
  padding: 16px 22px;
  border-left: 3px solid transparent;
  position: relative;
  transition: background 0.4s, border-color 0.4s, opacity 0.35s;
}
.demo-item + .demo-item {
  border-top: 1px solid var(--line);
}
.demo-item.is-ok {
  border-left-color: var(--brand);
  background: linear-gradient(90deg, rgba(18, 122, 110, 0.045), transparent 70%);
}
.demo-item .name {
  font-weight: 620;
  font-size: 15px;
}
.demo-item .desc {
  margin-top: 3px;
  font-size: 13px;
  color: var(--ink-4);
  line-height: 1.55;
}
.demo-item .right {
  display: flex;
  align-items: center;
  gap: 8px;
  position: relative;
}
.reason-chip {
  font-size: 11.5px;
  font-family: var(--font-mono, ui-monospace, monospace);
  padding: 3px 8px;
  border-radius: 6px;
  background: var(--bg);
  border: 1px solid var(--line);
  color: var(--ink-3);
  white-space: nowrap;
  opacity: 0;
  transform: translateX(6px);
  transition: opacity 0.28s var(--ease), transform 0.28s var(--ease), background 0.3s, color 0.3s, border-color 0.3s;
  pointer-events: none;
}
html[data-lang="en"] .reason-chip {
  position: absolute;
  right: calc(100% + 10px);
  top: 50%;
  transform: translateY(-50%) translateX(6px);
  z-index: 2;
}
html[data-lang="en"] .demo-item:hover .reason-chip,
html[data-lang="en"] .demo-item.show-reason .reason-chip,
html[data-lang="en"] .status-demo[data-focus="ok"] .demo-item[data-state="ok"] .reason-chip,
html[data-lang="en"] .status-demo[data-focus="warn"] .demo-item[data-state="warn"] .reason-chip,
html[data-lang="en"] .status-demo[data-focus="na"] .demo-item[data-state="na"] .reason-chip,
html[data-lang="en"] .status-demo[data-focus="read"] .demo-item[data-state="read"] .reason-chip {
  transform: translateY(-50%);
}
.reason-chip.chip-ok {
  color: var(--ok);
  background: var(--ok-soft);
  border-color: rgba(16, 185, 129, 0.2);
}
.reason-chip.chip-warn {
  color: var(--warn);
  background: var(--warn-soft);
  border-color: rgba(217, 119, 6, 0.2);
}
.reason-chip.chip-na {
  color: var(--na);
  background: var(--na-soft);
  border-color: rgba(148, 163, 184, 0.2);
}
.reason-chip.chip-read {
  color: var(--brand);
  background: var(--brand-soft);
  border-color: rgba(18, 122, 110, 0.2);
}
.demo-item:hover .reason-chip,
.demo-item.show-reason .reason-chip,
.status-demo[data-focus="ok"] .demo-item[data-state="ok"] .reason-chip,
.status-demo[data-focus="warn"] .demo-item[data-state="warn"] .reason-chip,
.status-demo[data-focus="na"] .demo-item[data-state="na"] .reason-chip,
.status-demo[data-focus="read"] .demo-item[data-state="read"] .reason-chip {
  opacity: 1;
  transform: none;
}
@media (max-width: 820px) {
  .reason-chip {
    display: none;
  }
}
.why {
  width: 26px;
  height: 26px;
  display: grid;
  place-items: center;
  border-radius: 50%;
  color: var(--ink-4);
  transition: color 0.2s, background 0.2s;
  position: relative;
}
.why:hover,
.why:focus-visible,
.why[aria-expanded="true"] {
  color: var(--ink);
  background: var(--bg-2);
}
.why .icon {
  width: 16px;
  height: 16px;
}
.tip {
  position: absolute;
  right: 0;
  bottom: calc(100% + 10px);
  width: 260px;
  padding: 12px 14px;
  border-radius: 12px;
  background: var(--ink);
  color: #e9f0ef;
  font-size: 12.5px;
  line-height: 1.6;
  text-align: left;
  box-shadow: var(--shadow-2);
  opacity: 0;
  transform: translateY(6px);
  pointer-events: none;
  transition: all 0.25s var(--ease);
  z-index: 5;
  font-weight: 400;
}
.tip b {
  color: #fff;
  display: block;
  margin-bottom: 2px;
}
.why:hover .tip,
.why:focus-visible .tip,
.why[aria-expanded="true"] .tip {
  opacity: 1;
  transform: none;
}
.toggle {
  width: 40px;
  height: 23px;
  border-radius: 999px;
  background: #dde5e4;
  position: relative;
  transition: background 0.4s var(--ease);
  flex: none;
}
.toggle::after {
  content: "";
  position: absolute;
  top: 3px;
  left: 3px;
  width: 17px;
  height: 17px;
  border-radius: 50%;
  background: #fff;
  box-shadow: 0 1px 3px rgba(0, 0, 0, 0.18);
  transition: transform 0.4s var(--ease);
}
.toggle.on {
  background: #1f6fd1;
}
.toggle.on::after {
  transform: translateX(17px);
}
.toggle.locked {
  opacity: 0.45;
}
.panel-foot {
  display: flex;
  align-items: center;
  gap: 18px;
  flex-wrap: wrap;
  padding: 14px 22px;
  border-top: 1px solid var(--line);
  background: var(--bg);
  border-radius: 0 0 var(--r-lg) var(--r-lg);
  font-size: 12.5px;
  color: var(--ink-3);
}
.panel-foot b {
  font-family: var(--font-mono);
  color: var(--ink);
  font-weight: 600;
}
.panel-foot .sep {
  width: 1px;
  height: 12px;
  background: var(--line-2);
}
.demo-note {
  margin-top: 16px;
  font-size: 12.5px;
  color: var(--ink-4);
  text-align: center;
}

/* ==========================================================
   MODULES
   ========================================================== */
.mod-groups {
  display: grid;
  grid-template-columns: 8fr 6fr;
  gap: 20px;
}
.mod-group {
  padding: 28px;
}
.mod-group-head {
  display: flex;
  align-items: baseline;
  justify-content: space-between;
  margin-bottom: 20px;
}
.mod-group-head h3 {
  font-size: 18px;
  font-weight: 680;
}
.mod-group-head > span {
  font-family: var(--font-mono);
  font-size: 12.5px;
  color: var(--ink-4);
}
.mod-grid {
  display: grid;
  grid-template-columns: repeat(4, 1fr);
  gap: 10px;
}
.mod-group.win .mod-grid {
  grid-template-columns: repeat(3, 1fr);
}
.mod {
  position: relative;
  padding: 18px 14px 16px;
  border-radius: 14px;
  background: var(--bg);
  border: 1px solid transparent;
  transition: all 0.35s var(--ease);
  min-height: 116px;
}
.mod .icon {
  width: 22px;
  height: 22px;
  color: var(--ink-2);
  transition: color 0.3s, transform 0.4s var(--ease);
}
.mod b {
  display: block;
  margin-top: 16px;
  font-size: 14.5px;
  font-weight: 620;
}
.mod small {
  display: block;
  margin-top: 4px;
  font-size: 12px;
  color: var(--ink-4);
  line-height: 1.5;
}
.mod:hover {
  background: #fff;
  border-color: var(--line);
  box-shadow: var(--shadow-2);
  transform: translateY(-2px);
}
.mod:hover .icon {
  color: var(--brand);
  transform: scale(1.08);
}
.tools {
  margin-top: 20px;
  padding: 22px 28px;
  display: flex;
  align-items: center;
  gap: 18px 28px;
  flex-wrap: wrap;
}
.tools h3 {
  font-size: 16px;
  font-weight: 680;
  margin-right: 8px;
}
html[data-lang="en"] .tools h3 {
  flex-basis: 100%;
  margin-right: 0;
  margin-bottom: -4px;
}
.tool {
  display: inline-flex;
  align-items: center;
  gap: 8px;
  font-size: 14px;
  color: var(--ink-2);
}
.tool .icon {
  width: 17px;
  height: 17px;
  color: var(--brand);
}

/* ==========================================================
   SHOWCASE (sticky zoom)
   ========================================================== */
.showcase {
  position: relative;
  height: 240vh;
}
.showcase-sticky {
  position: sticky;
  top: 0;
  height: 100vh;
  display: flex;
  flex-direction: column;
  justify-content: center;
  overflow: hidden;
  padding: calc(var(--nav-h) + 8px) 0 24px;
}
.showcase-head {
  display: flex;
  align-items: flex-end;
  justify-content: space-between;
  gap: 24px;
  margin-bottom: 28px;
}
.showcase-head .h2 {
  font-size: clamp(30px, 3.6vw, 44px);
}
.showcase-head .kicker {
  margin-bottom: 12px;
}
.tabs {
  display: inline-flex;
  padding: 4px;
  border-radius: 999px;
  background: rgba(14, 20, 20, 0.05);
  flex: none;
}
.tabs button {
  height: 36px;
  padding: 0 16px;
  border-radius: 999px;
  font-size: 14px;
  font-weight: 600;
  color: var(--ink-3);
  transition: all 0.3s var(--ease);
}
.tabs button[aria-selected="true"] {
  background: #fff;
  color: var(--ink);
  box-shadow: var(--shadow-1);
}
.zoom-frame {
  position: relative;
  flex: 0 1 auto;
  --fh: calc(100vh - 300px);
  max-height: var(--fh);
  aspect-ratio: 1568 / 960;
  margin-inline: auto;
  width: 100%;
  max-width: calc(var(--fh) * 1568 / 960);
  border-radius: 16px;
  overflow: hidden;
  background: #fff;
  box-shadow: 0 0 0 1px rgba(14, 20, 20, 0.07), var(--shadow-3);
}
.zoom-img {
  --z: 0;
  position: absolute;
  inset: 0;
  width: 100%;
  height: 100%;
  object-fit: cover;
  transform-origin: var(--ox, 50%) var(--oy, 50%);
  transform: scale(calc(1 + 0.55 * var(--z)));
  transition: opacity 0.5s var(--ease);
  will-change: transform;
}
.zoom-img[hidden] {
  display: block;
  opacity: 0;
  pointer-events: none;
}
.callout {
  position: absolute;
  z-index: 3;
  max-width: 330px;
  padding: 14px 16px;
  border-radius: 14px;
  background: rgba(14, 20, 20, 0.88);
  backdrop-filter: blur(8px);
  -webkit-backdrop-filter: blur(8px);
  color: #eef4f3;
  font-size: 13.5px;
  line-height: 1.6;
  box-shadow: var(--shadow-2);
  opacity: 0;
  transform: translateY(10px);
  transition: opacity 0.5s var(--ease), transform 0.5s var(--ease);
  pointer-events: none;
}
.callout small {
  display: block;
  color: #8fd3c8;
  font-size: 11.5px;
  font-weight: 600;
  letter-spacing: 0.08em;
  text-transform: uppercase;
  margin-bottom: 4px;
}
.callout.show {
  opacity: 1;
  transform: none;
}
.showcase-note {
  margin-top: 16px;
  text-align: center;
  font-size: 12.5px;
  color: var(--ink-4);
}

/* ==========================================================
   TICKER (module names marquee)
   ========================================================== */
.ticker {
  overflow: hidden;
  border-top: 1px solid var(--line);
  border-bottom: 1px solid var(--line);
  padding: 14px 0;
  margin-bottom: clamp(96px, 13vw, 168px);
  -webkit-mask-image: linear-gradient(90deg, transparent, #000 8%, #000 92%, transparent);
  mask-image: linear-gradient(90deg, transparent, #000 8%, #000 92%, transparent);
}
.ticker-track {
  display: flex;
  width: max-content;
  animation: ticker 80s linear infinite;
}
.ticker:hover .ticker-track {
  animation-play-state: paused;
}
.ticker-set {
  flex: none;
  padding-right: 48px;
}
.ticker-set .zh,
.ticker-set .en {
  font-size: 13px;
  font-weight: 550;
  letter-spacing: 0.14em;
  color: var(--ink-4);
  white-space: nowrap;
  font-variant-numeric: tabular-nums;
}
.ticker-set i {
  font-style: normal;
  color: var(--brand);
  margin: 0 22px;
  font-size: 10px;
  vertical-align: 1px;
}
@keyframes ticker {
  to { transform: translateX(-50%); }
}
@media (prefers-reduced-motion: reduce) {
  .ticker-track {
    animation: none;
  }
}

/* ==========================================================
   LIVE PREVIEW (real app UI embedded)
   ========================================================== */
.live-stage {
  margin-top: clamp(36px, 5vw, 56px);
}
/* generic embeddable app visual — used in hero and the interface section.
   1280×860 design coords, JS scales the iframe to the container. */
.app-embed {
  position: relative;
  overflow: hidden;
  aspect-ratio: 1280 / 860;
  background: #e2e8f0;
}
.app-embed iframe {
  display: block;
  width: 1280px;
  height: 860px;
  border: 0;
  transform-origin: 0 0;
  background: #e2e8f0;
}
.app-embed .fallback-shot {
  display: none;
  width: 100%;
}
.app-embed.fallback iframe {
  display: none;
}
.app-embed.fallback {
  aspect-ratio: auto;
  background: none;
}
.app-embed.fallback .fallback-shot {
  display: block;
}
.embed-live {
  position: absolute;
  left: 16px;
  bottom: 14px;
  z-index: 3;
  display: inline-flex;
  align-items: center;
  gap: 7px;
  padding: 5px 12px;
  border-radius: 999px;
  background: rgba(14, 20, 20, 0.68);
  -webkit-backdrop-filter: blur(8px);
  backdrop-filter: blur(8px);
  color: #fff;
  font-size: 11.5px;
  font-weight: 600;
  letter-spacing: 0.05em;
  pointer-events: none;
}
.embed-live i {
  width: 6px;
  height: 6px;
  border-radius: 50%;
  background: #2bd4c0;
  animation: dotPulse 1.6s ease-in-out infinite;
}
@keyframes dotPulse {
  50% {
    opacity: 0.3;
  }
}
.app-embed.fallback .embed-live {
  display: none;
}
/* poster state: static preview until the user asks for the live app */
.app-embed.poster iframe {
  display: none;
}
.app-embed.poster .fallback-shot {
  display: block;
}
.app-embed.poster .live-hint {
  display: none;
}
.embed-load {
  position: absolute;
  inset: 0;
  z-index: 3;
  display: grid;
  place-items: center;
  border: 0;
  padding: 0;
  background: transparent;
  cursor: pointer;
}
.embed-load::before {
  content: "";
  position: absolute;
  inset: 0;
  background: transparent;
  transition: background 0.35s;
}
.embed-load:hover::before {
  background: rgba(246, 248, 248, 0.08);
}
.load-pill {
  position: relative;
  display: inline-flex;
  align-items: center;
  gap: 10px;
  padding: 13px 22px;
  border-radius: 999px;
  background: rgba(14, 20, 20, 0.82);
  -webkit-backdrop-filter: blur(10px);
  backdrop-filter: blur(10px);
  color: #fff;
  font-size: 14.5px;
  font-weight: 600;
  box-shadow: var(--shadow-3);
  transition: transform 0.3s var(--ease), background 0.3s;
}
.embed-load:hover .load-pill {
  transform: scale(1.04);
  background: rgba(14, 20, 20, 0.9);
}
.load-pill .icon {
  width: 16px;
  height: 16px;
}
.app-embed:not(.poster) .embed-load,
.app-embed.fallback .embed-load {
  display: none;
}
.hero-window .app-embed {
  aspect-ratio: 1280 / 860;
}
.hero-window .app-embed.fallback {
  aspect-ratio: auto;
}
.live-frame {
  position: relative;
  border-radius: var(--r-lg);
  overflow: hidden;
  box-shadow: 0 0 0 1px rgba(14, 20, 20, 0.07), var(--shadow-3);
}
.live-hint {
  position: absolute;
  right: 16px;
  bottom: 16px;
  z-index: 2;
  display: inline-flex;
  align-items: center;
  gap: 7px;
  padding: 8px 14px;
  border-radius: 999px;
  background: rgba(14, 20, 20, 0.72);
  color: #fff;
  font-size: 12.5px;
  font-weight: 550;
  letter-spacing: 0.02em;
  -webkit-backdrop-filter: blur(10px);
  backdrop-filter: blur(10px);
  pointer-events: none;
  opacity: 0;
  animation: liveHintIn 0.6s var(--ease) 1.2s forwards, liveHintOut 0.8s var(--ease) 7s forwards;
}
.live-hint .icon {
  width: 14px;
  height: 14px;
}
@keyframes liveHintIn {
  from { opacity: 0; transform: translateY(8px); }
  to { opacity: 0.94; transform: none; }
}
@keyframes liveHintOut {
  to { opacity: 0; transform: translateY(6px); }
}
.live-foot {
  margin-top: 16px;
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 14px;
  flex-wrap: wrap;
}
.live-foot .muted {
  font-size: 13px;
  color: var(--ink-4);
}
.live-actions {
  display: flex;
  gap: 10px;
  flex-wrap: wrap;
}
.live-frame:has(.app-embed.fallback) {
  box-shadow: none;
  border-radius: 0;
  overflow: visible;
}
.live-frame .fallback-shot {
  border-radius: var(--r-lg);
  box-shadow: 0 0 0 1px rgba(14, 20, 20, 0.07), var(--shadow-3);
}

/* ==========================================================
   SAFETY
   ========================================================== */
.safety-grid {
  display: grid;
  grid-template-columns: repeat(4, 1fr);
  gap: 16px;
}
.safe {
  padding: 28px 24px;
  transition: transform 0.5s var(--ease), box-shadow 0.5s var(--ease);
}
.safe:hover {
  transform: translateY(-3px);
  box-shadow: var(--shadow-2);
}
.safe .ic {
  width: 44px;
  height: 44px;
  border-radius: 12px;
  display: grid;
  place-items: center;
  background: var(--brand-soft);
  color: var(--brand);
}
.safe .ic .icon {
  width: 22px;
  height: 22px;
}
.safe h3 {
  margin-top: 22px;
  font-size: 18px;
  font-weight: 680;
}
.safe p {
  margin-top: 8px;
  font-size: 14.5px;
  color: var(--ink-3);
  line-height: 1.7;
}
.fineprint {
  margin-top: 28px;
  display: flex;
  gap: 12px;
  align-items: flex-start;
  padding: 18px 22px;
  border-radius: var(--r-md);
  background: var(--warn-soft);
  color: #7a5310;
  font-size: 14px;
  line-height: 1.7;
}
.fineprint .icon {
  margin-top: 3px;
  color: var(--warn);
  flex: none;
}
.fineprint-list {
  list-style: none;
  display: grid;
  gap: 8px;
  margin: 0;
  padding: 0;
}
.fineprint-list b {
  font-weight: 650;
}

/* ==========================================================
   AUTHOR (the only dark block)
   ========================================================== */
.author {
  position: relative;
  overflow: hidden;
  border-radius: var(--r-xl);
  background: #0d1413;
  color: #e7efee;
  padding: clamp(48px, 7vw, 96px);
  isolation: isolate;
}
.author .grid-bg {
  --grid: rgba(143, 211, 200, 0.06);
  -webkit-mask-image: radial-gradient(ellipse at 85% 20%, #000, transparent 65%);
  mask-image: radial-gradient(ellipse at 85% 20%, #000, transparent 65%);
}
.author::before {
  content: "";
  position: absolute;
  right: -10%;
  top: -40%;
  width: 70%;
  aspect-ratio: 1;
  background: radial-gradient(closest-side, rgba(18, 122, 110, 0.35), transparent);
  z-index: -1;
}
.author-logo {
  position: absolute;
  right: clamp(24px, 6vw, 80px);
  bottom: clamp(24px, 5vw, 64px);
  width: clamp(120px, 18vw, 230px);
  opacity: 0.07;
  z-index: -1;
}
.author .kicker {
  color: #8fd3c8;
}
.author h2 {
  color: #fff;
}
.author-body {
  margin-top: 26px;
  max-width: 640px;
  font-size: clamp(16.5px, 1.5vw, 18.5px);
  line-height: 1.85;
  color: #b6c5c3;
}
.author-body p + p {
  margin-top: 14px;
}
.author-sign {
  margin-top: 34px;
  display: flex;
  align-items: center;
  gap: 14px;
  flex-wrap: wrap;
}
.author-sign .name {
  font-size: 17px;
  font-weight: 650;
  color: #fff;
  margin-right: 10px;
}
.social {
  display: inline-flex;
  align-items: center;
  gap: 7px;
  height: 36px;
  padding: 0 14px;
  border-radius: 999px;
  border: 1px solid rgba(255, 255, 255, 0.14);
  color: #d5e2e0;
  font-size: 13.5px;
  transition: background 0.25s, border-color 0.25s, color 0.25s;
}
.social:hover {
  background: rgba(255, 255, 255, 0.08);
  border-color: rgba(255, 255, 255, 0.28);
  color: #fff;
}
.social .icon {
  width: 15px;
  height: 15px;
}
.author .btn-ghost {
  background: transparent;
  color: #fff;
  border-color: rgba(255, 255, 255, 0.22);
}
.author .btn-ghost:hover {
  background: rgba(255, 255, 255, 0.08);
}

/* ==========================================================
   DOWNLOAD
   ========================================================== */
/* ---------- fit: honest self-selection ---------- */
.fit-grid {
  margin: 0 auto;
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: 20px;
}
.fit-card {
  padding: 28px 30px;
  position: relative;
  display: flex;
  flex-direction: column;
  transition: transform 0.4s var(--ease), box-shadow 0.4s var(--ease), border-color 0.4s;
}
.fit-card:hover {
  transform: translateY(-2px);
  box-shadow: var(--shadow-2);
  border-color: var(--line-2);
}
.fit-top {
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 12px;
  margin-bottom: 18px;
}
.fit-badge {
  display: inline-flex;
  align-items: center;
  padding: 4px 10px;
  border-radius: 999px;
  font-size: 12px;
  font-weight: 600;
  background: var(--bg);
  color: var(--ink-4);
  border: 1px solid var(--line);
}
.fit-badge.ok {
  background: var(--ok-soft);
  color: var(--ok);
  border-color: transparent;
}
.fit-yes .fit-verdict {
  color: var(--brand);
}
.fit-no .fit-verdict {
  color: var(--ink-3);
}
.fit-card h3 {
  display: flex;
  align-items: center;
  gap: 9px;
  font-size: 17px;
  font-weight: 650;
  margin: 0;
}
.fit-card h3 .icon {
  width: 19px;
  height: 19px;
}
.fit-yes h3 .icon {
  color: var(--ok);
}
.fit-no h3 .icon {
  color: var(--ink-4);
}
.fit-card ul {
  list-style: none;
  margin: 0;
  padding: 0;
  display: grid;
  gap: 11px;
}
.fit-card li {
  display: flex;
  align-items: baseline;
  gap: 10px;
  font-size: 14.5px;
  line-height: 1.65;
  color: var(--ink-2);
}
.fit-card li .icon {
  width: 14px;
  height: 14px;
  flex: none;
  transform: translateY(2px);
}
.fit-yes li .icon {
  color: var(--ok);
}
.fit-no li .icon {
  color: var(--ink-4);
}
.fit-no li {
  color: var(--ink-3);
}
.fit-verdict {
  margin-top: auto;
  padding-top: 18px;
  border-top: 1px solid var(--line);
  font-size: 15px;
  font-weight: 650;
  color: var(--text);
}
.fit-card ul + .fit-verdict {
  margin-top: 22px;
}
.fit-note {
  display: flex;
  gap: 10px;
  align-items: flex-start;
  margin-top: 20px;
  font-size: 13.5px;
  line-height: 1.75;
  color: var(--sub);
}
.fit-note .icon {
  width: 16px;
  height: 16px;
  flex: none;
  margin-top: 3px;
  color: var(--sub2);
}
.safe-banner {
  display: flex;
  align-items: center;
  gap: 14px;
  padding: 16px 20px;
  background: linear-gradient(90deg, rgba(18, 122, 110, 0.08) 0%, rgba(18, 122, 110, 0.02) 100%);
  border: 1px solid rgba(18, 122, 110, 0.24);
  border-radius: var(--r-md);
  margin-bottom: 32px;
  font-size: 14px;
  line-height: 1.6;
  color: var(--ink-2);
}
.safe-banner .icon {
  width: 22px;
  height: 22px;
  color: var(--brand);
  flex: none;
}
.safe-banner b {
  color: var(--ink);
  font-weight: 650;
}
.legend-note {
  margin-top: 20px;
  font-size: 13.5px;
  color: var(--ink-4);
}
.dl-head {
  text-align: left;
}
.dl-pick {
  margin: 0 0 24px;
  padding: 14px 20px;
  font-size: 14px;
  line-height: 1.7;
  color: var(--ink-3);
  background: var(--card);
  border: 1px solid var(--line);
  border-radius: var(--r-md);
}
.dl-pick b {
  color: var(--ink);
  font-weight: 650;
}
.dl-grid {
  margin-top: 24px;
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: 20px;
}
.ver {
  padding: 32px;
  display: flex;
  flex-direction: column;
  position: relative;
  overflow: hidden;
}
.ver.primary {
  border-color: rgba(18, 122, 110, 0.35);
  box-shadow: 0 0 0 4px var(--brand-soft), var(--shadow-2);
}
.ver-top {
  display: flex;
  align-items: center;
  gap: 10px;
  flex-wrap: wrap;
}
.ver-tag {
  height: 24px;
  display: inline-flex;
  align-items: center;
  padding: 0 10px;
  border-radius: 999px;
  font-size: 12px;
  font-weight: 650;
  background: var(--bg-2);
  color: var(--ink-2);
}
.ver.primary .ver-tag {
  background: var(--brand-soft);
  color: var(--brand);
}
.ver-date {
  margin-left: auto;
  font-family: var(--font-mono);
  font-size: 12.5px;
  color: var(--ink-4);
}
.ver h3 {
  margin-top: 18px;
  font-family: var(--font-mono);
  font-size: 30px;
  font-weight: 600;
  letter-spacing: -0.02em;
}
.ver .desc {
  margin-top: 8px;
  color: var(--ink-3);
  font-size: 15px;
  line-height: 1.7;
  min-height: 3.4em;
}
.ver ul {
  list-style: none;
  padding: 0;
  margin: 18px 0 0;
  display: grid;
  gap: 8px;
  font-size: 14px;
  color: var(--ink-2);
}
.ver li {
  display: flex;
  gap: 9px;
  align-items: flex-start;
}
.ver li .icon {
  width: 16px;
  height: 16px;
  margin-top: 4px;
  flex: none;
  color: var(--ok);
}
.ver li.warn .icon {
  color: var(--warn);
}
.ver-actions {
  margin-top: auto;
  padding-top: 26px;
  display: grid;
  gap: 10px;
}
.file-btn {
  display: flex;
  align-items: center;
  gap: 12px;
  padding: 13px 16px;
  border-radius: 14px;
  border: 1px solid var(--line);
  background: var(--bg);
  transition: all 0.3s var(--ease);
}
.file-btn:hover {
  border-color: var(--ink-4);
  background: #fff;
  transform: translateY(-1px);
  box-shadow: var(--shadow-1);
}
.file-btn.main {
  background: var(--ink);
  border-color: var(--ink);
  color: #fff;
}
.file-btn.main:hover {
  background: #1d2828;
}
.file-btn .icon {
  width: 20px;
  height: 20px;
}
.file-btn b {
  display: block;
  font-size: 14.5px;
  font-weight: 620;
}
.file-btn small {
  display: block;
  font-size: 12px;
  opacity: 0.6;
  font-family: var(--font-mono);
}
.file-btn .size {
  margin-left: auto;
  font-family: var(--font-mono);
  font-size: 12.5px;
  opacity: 0.65;
}
.dl-foot {
  margin-top: 24px;
  display: flex;
  align-items: center;
  justify-content: space-between;
  flex-wrap: wrap;
  gap: 10px 24px;
  font-size: 14px;
  color: var(--ink-3);
  line-height: 1.7;
}
.dl-foot a {
  color: var(--brand);
  font-weight: 600;
}
.dl-foot a:hover {
  text-decoration: underline;
  text-underline-offset: 3px;
}
.req {
  display: inline-flex;
  flex-wrap: wrap;
  gap: 6px 18px;
  font-family: var(--font-mono);
  font-size: 12.5px;
  color: var(--ink-4);
}
html[data-lang="en"] .req {
  flex-basis: 100%;
}

/* ==========================================================
   FOOTER
   ========================================================== */
.footer {
  border-top: 1px solid var(--line);
  padding: 56px 0 40px;
  font-size: 14px;
  color: var(--ink-3);
}
.footer-top {
  display: grid;
  grid-template-columns: 1.4fr repeat(3, 1fr);
  gap: 40px;
}
.footer .brand {
  font-size: 16px;
}
.footer-motto {
  margin-top: 14px;
  max-width: 300px;
  line-height: 1.75;
}
.footer h4 {
  font-size: 13px;
  font-weight: 650;
  color: var(--ink);
  margin-bottom: 14px;
}
.footer ul {
  list-style: none;
  padding: 0;
  margin: 0;
  display: grid;
  gap: 9px;
}
.footer ul a:hover {
  color: var(--ink);
}
.footer-bottom {
  margin-top: 48px;
  padding-top: 22px;
  border-top: 1px solid var(--line);
  display: flex;
  justify-content: space-between;
  align-items: center;
  gap: 16px;
  flex-wrap: wrap;
  font-size: 12.5px;
  color: var(--ink-4);
}
.footer-bottom-right {
  display: inline-flex;
  align-items: center;
  gap: 18px;
  flex-wrap: wrap;
}
.to-top {
  display: inline-flex;
  align-items: center;
  gap: 6px;
  color: var(--ink-3);
  font-weight: 550;
  transition: color 0.25s;
}
.to-top .icon {
  width: 12px;
  height: 12px;
  transform: rotate(-90deg);
  transition: transform 0.3s var(--ease);
}
.to-top:hover {
  color: var(--ink);
}
.to-top:hover .icon {
  transform: rotate(-90deg) translateX(3px);
}

/* ==========================================================
   SUB PAGES
   ========================================================== */
.page-hero {
  position: relative;
  overflow: hidden;
  margin-top: calc(var(--nav-h) * -1);
  padding: calc(var(--nav-h) + clamp(64px, 9vw, 120px)) 0 clamp(48px, 6vw, 80px);
}
.page-hero .grid-bg {
  -webkit-mask-image: radial-gradient(ellipse 60% 80% at 50% 0%, #000 10%, transparent 70%);
  mask-image: radial-gradient(ellipse 60% 80% at 50% 0%, #000 10%, transparent 70%);
}
.page-hero .h1 {
  position: relative;
  font-size: clamp(38px, 5.6vw, 66px);
  line-height: 1.1;
  letter-spacing: -0.03em;
  font-weight: 740;
}
html[data-lang="zh"] .page-hero .h1 {
  letter-spacing: -0.015em;
  line-height: 1.18;
}
.page-hero .lead {
  position: relative;
  max-width: 640px;
}
.page-body {
  padding-bottom: clamp(80px, 10vw, 140px);
}
.block + .block {
  margin-top: clamp(64px, 8vw, 104px);
}
.block-title {
  display: flex;
  align-items: baseline;
  gap: 14px;
  margin-bottom: 26px;
}
.block-title .n {
  font-family: var(--font-mono);
  font-size: 13px;
  color: var(--brand);
}
.block-title h2 {
  font-size: clamp(24px, 2.6vw, 32px);
  letter-spacing: -0.015em;
  font-weight: 700;
}

/* code block */
.code {
  position: relative;
  border-radius: var(--r-md);
  background: #0f1716;
  color: #d8e6e4;
  padding: 18px 20px;
  padding-right: 96px;
  font-family: var(--font-mono);
  font-size: 13.5px;
  line-height: 1.7;
  overflow-x: auto;
  white-space: pre;
}
.code .c {
  color: #6f8b87;
}
.code .k {
  color: #8fd3c8;
}
.copy {
  position: absolute;
  top: 12px;
  right: 12px;
  height: 32px;
  padding: 0 12px;
  display: inline-flex;
  align-items: center;
  gap: 6px;
  border-radius: 8px;
  background: rgba(255, 255, 255, 0.08);
  color: #d8e6e4;
  font-family: var(--font-sans);
  font-size: 12.5px;
  font-weight: 600;
  transition: background 0.2s;
}
.copy:hover {
  background: rgba(255, 255, 255, 0.16);
}
.copy .icon {
  width: 14px;
  height: 14px;
}
.copy.done {
  color: #7fe0b0;
  animation: copyPop 0.32s var(--ease) forwards;
}
@keyframes copyPop {
  0% { transform: scale(0.92); }
  60% { transform: scale(1.08); }
  100% { transform: scale(1); }
}
.code.light {
  background: #fff;
  color: var(--ink-2);
  border: 1px solid var(--line);
}
.code.light .copy {
  background: var(--bg-2);
  color: var(--ink-2);
}
.code.light .copy:hover {
  background: var(--line);
}

/* steps */
.steps {
  display: grid;
  grid-template-columns: repeat(4, 1fr);
  gap: 16px;
  counter-reset: s;
}
.steps.three {
  grid-template-columns: repeat(3, 1fr);
}
.step-card {
  padding: 24px;
  position: relative;
}
.step-card::before {
  counter-increment: s;
  content: counter(s, decimal-leading-zero);
  font-family: var(--font-mono);
  font-size: 13px;
  color: var(--brand);
}
.step-card h3 {
  margin-top: 14px;
  font-size: 17px;
  font-weight: 680;
}
.step-card p {
  margin-top: 8px;
  font-size: 14.5px;
  color: var(--ink-3);
  line-height: 1.7;
}

/* table */
.table {
  width: 100%;
  border-collapse: separate;
  border-spacing: 0;
  background: #fff;
  border: 1px solid var(--line);
  border-radius: var(--r-md);
  overflow: hidden;
  font-size: 15px;
}
.table th,
.table td {
  text-align: left;
  padding: 16px 20px;
  vertical-align: top;
}
.table th {
  font-size: 12.5px;
  font-weight: 650;
  color: var(--ink-3);
  letter-spacing: 0.04em;
  background: var(--bg);
  border-bottom: 1px solid var(--line);
}
.table td {
  border-top: 1px solid var(--line);
  color: var(--ink-2);
}
.table tr:first-child td {
  border-top: 0;
}
.table td:first-child {
  white-space: nowrap;
  width: 1%;
  color: var(--ink);
  font-weight: 600;
}

/* faq */
.faq {
  border-top: 1px solid var(--line);
}
.faq details {
  border-bottom: 1px solid var(--line);
}
.faq summary {
  list-style: none;
  display: flex;
  align-items: center;
  gap: 16px;
  padding: 24px 4px;
  cursor: pointer;
  font-size: 17.5px;
  font-weight: 620;
}
.faq summary::-webkit-details-marker {
  display: none;
}
.faq summary .pm {
  margin-left: auto;
  width: 28px;
  height: 28px;
  border-radius: 50%;
  border: 1px solid var(--line-2);
  display: grid;
  place-items: center;
  flex: none;
  transition: transform 0.35s var(--ease), background 0.3s;
}
.faq summary .pm .icon {
  width: 14px;
  height: 14px;
}
.faq details[open] summary .pm {
  transform: rotate(45deg);
  background: var(--ink);
  color: #fff;
  border-color: var(--ink);
}
.faq .ans {
  padding: 0 4px 26px;
  max-width: 760px;
  color: var(--ink-3);
  font-size: 15.5px;
  line-height: 1.8;
}

/* timeline (story) */
.timeline {
  position: relative;
  margin-left: 8px;
  padding-left: 40px;
}
.timeline::before {
  content: "";
  position: absolute;
  left: 0;
  top: 8px;
  bottom: 8px;
  width: 2px;
  background: linear-gradient(var(--line-2), var(--line-2) 70%, transparent);
}
.tl-item {
  position: relative;
  padding-bottom: 46px;
}
.tl-item::before {
  content: "";
  position: absolute;
  left: -47px;
  top: 6px;
  width: 16px;
  height: 16px;
  border-radius: 50%;
  background: var(--bg);
  border: 2px solid var(--ink-4);
}
.tl-item.ok::before {
  border-color: var(--brand);
  background: var(--brand);
  box-shadow: 0 0 0 5px var(--brand-soft);
}
.tl-item.bad::before {
  border-color: var(--bad);
  background: var(--bad);
  box-shadow: 0 0 0 5px var(--bad-soft);
}
.tl-date {
  font-family: var(--font-mono);
  font-size: 13px;
  color: var(--ink-4);
}
.tl-item h3 {
  margin-top: 6px;
  font-size: 20px;
  font-weight: 680;
  letter-spacing: -0.01em;
}
.tl-item p {
  margin-top: 8px;
  max-width: 680px;
  color: var(--ink-3);
  font-size: 15.5px;
  line-height: 1.8;
}
.quote {
  position: relative;
  margin: 0;
  padding: clamp(32px, 4vw, 48px);
  border-radius: var(--r-lg);
  background: #fff;
  border: 1px solid var(--line);
  font-size: clamp(19px, 2vw, 24px);
  line-height: 1.75;
  letter-spacing: -0.005em;
  font-weight: 560;
  color: var(--ink);
}
.quote footer {
  margin-top: 20px;
  font-size: 14px;
  font-weight: 500;
  color: var(--ink-4);
}
.prose {
  max-width: 720px;
  color: var(--ink-2);
  font-size: 16.5px;
  line-height: 1.9;
}
.prose p + p {
  margin-top: 16px;
}
.prose a,
.faq .ans a,
.step-card a {
  color: var(--brand);
  text-decoration: none;
  border-bottom: 1px solid rgba(11, 107, 86, 0.3);
  transition: border-color 0.2s;
}
.prose a:hover,
.faq .ans a:hover,
.step-card a:hover {
  border-bottom-color: var(--brand);
}
.prose code,
.faq .ans code {
  font-family: var(--font-mono);
  font-size: 0.86em;
  background: var(--bg-2);
  border: 1px solid var(--line);
  border-radius: 6px;
  padding: 1px 6px;
}
.two-col {
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: 16px;
}
.list-card {
  padding: 26px;
}
.list-card h3 {
  display: flex;
  align-items: center;
  gap: 10px;
  font-size: 17px;
  font-weight: 680;
}
.list-card h3 .icon {
  color: var(--ok);
}
.list-card.no h3 .icon {
  color: var(--bad);
}
.list-card ul {
  margin: 14px 0 0;
  padding-left: 20px;
  color: var(--ink-3);
  font-size: 15px;
  line-height: 1.9;
}
.toast {
  position: fixed;
  left: 50%;
  bottom: 28px;
  transform: translate(-50%, 20px);
  padding: 11px 18px;
  border-radius: 999px;
  background: var(--ink);
  color: #fff;
  font-size: 14px;
  box-shadow: var(--shadow-2);
  opacity: 0;
  pointer-events: none;
  transition: all 0.35s var(--ease);
  z-index: 100;
}
.toast.show {
  opacity: 1;
  transform: translate(-50%, 0);
}

/* ==========================================================
   RESPONSIVE
   ========================================================== */
@media (max-width: 1080px) {
  .nav-links {
    display: none;
  }
  .menu-btn {
    display: grid;
  }
  .nav-cta {
    display: none;
  }
  .mobile-menu {
    position: fixed;
    inset: var(--nav-h) 0 auto 0;
    z-index: 49;
    display: grid;
    gap: 2px;
    padding: 12px 24px 24px;
    background: rgba(246, 248, 248, 0.97);
    backdrop-filter: blur(16px);
    -webkit-backdrop-filter: blur(16px);
    border-bottom: 1px solid var(--line);
    transform: translateY(-8px);
    opacity: 0;
    pointer-events: none;
    transition: all 0.3s var(--ease);
  }
  .mobile-menu.open {
    transform: none;
    opacity: 1;
    pointer-events: auto;
  }
  .mobile-menu a {
    padding: 13px 4px;
    font-size: 17px;
    font-weight: 600;
    border-bottom: 1px solid var(--line);
  }
  .mobile-menu .btn {
    margin-top: 14px;
  }
  .what-grid {
    grid-template-columns: 1fr;
    max-width: 560px;
    margin-inline: auto;
  }
  .flow-cols {
    gap: 32px;
  }
  .term-body {
    font-size: 12px;
  }
  .status-wrap {
    grid-template-columns: 1fr;
  }
  .mod-groups {
    grid-template-columns: 1fr;
  }
  .safety-grid {
    grid-template-columns: 1fr 1fr;
  }
  .float-chip {
    display: none;
  }
  .footer-top {
    grid-template-columns: 1fr 1fr;
  }
  .steps {
    grid-template-columns: 1fr 1fr;
  }
}
@media (max-width: 760px) {
  body {
    font-size: 16px;
  }
  .wrap {
    width: calc(100% - 36px);
  }
  .brand small {
    display: none;
  }
  .hero-ctas .btn {
    width: 100%;
    max-width: 340px;
  }
  html[data-lang="en"] .hero-title .line {
    white-space: normal;
  }
  html[data-lang="zh"] .hero-title {
    font-size: clamp(30px, 9.6vw, 46px);
  }
  .flow-pin {
    height: auto;
  }
  .flow-sticky {
    position: static;
    min-height: 0;
    padding: 0;
  }
  .flow-cols {
    grid-template-columns: 1fr;
    gap: 0;
  }
  .flow-steps {
    max-width: 460px;
    margin-inline: auto;
  }
  .fstep {
    opacity: 1;
    padding: 0 0 26px 58px;
  }
  .fstep .flow-node {
    top: 0;
    background: #fff;
  }
  .fstep::before {
    left: 20px;
    top: 44px;
    bottom: 2px;
  }
  .fstep.lit .flow-node {
    color: #fff;
    background: var(--brand);
    border-color: var(--brand);
  }
  .flow-stage,
  .flow-bar {
    display: none;
  }
  .mod-grid,
  .mod-group.win .mod-grid {
    grid-template-columns: 1fr 1fr;
  }
  .safety-grid,
  .dl-grid,
  .fit-grid,
  .two-col,
  .steps,
  .steps.three {
    grid-template-columns: 1fr;
  }
  .showcase {
    height: auto;
  }
  .showcase-sticky {
    position: relative;
    height: auto;
    padding: 96px 0;
  }
  .showcase-head {
    flex-direction: column;
    align-items: flex-start;
  }
  .zoom-frame {
    max-height: none;
    max-width: 100%;
  }
  .callout {
    display: none;
  }
  .footer-top {
    grid-template-columns: 1fr;
    gap: 28px;
  }
  .table th,
  .table td {
    padding: 13px 14px;
    font-size: 14px;
  }
  .table td:first-child {
    white-space: normal;
  }
  .tip {
    width: 220px;
  }
  .demo-item {
    padding: 14px 16px;
  }
  .panel-head {
    padding: 16px;
    flex-wrap: wrap;
  }
}

/* ==========================================================
   TACTILE SURFACES — cursor spotlight / hairline / border beam
   ========================================================== */
.card,
.list-card {
  position: relative;
}
.card::before,
.list-card::before {
  content: "";
  position: absolute;
  top: 0;
  left: 14%;
  right: 14%;
  height: 1px;
  z-index: 2;
  background: linear-gradient(90deg, transparent, rgba(20, 160, 146, 0.5), transparent);
  opacity: 0;
  transition: opacity 0.5s var(--ease);
  pointer-events: none;
}
.card:hover::before,
.list-card:hover::before {
  opacity: 1;
}
:is(.card, .step-card, .list-card, .ver, .fit-card)::after {
  content: "";
  position: absolute;
  inset: 0;
  border-radius: inherit;
  z-index: 2;
  background: radial-gradient(
    340px circle at var(--mx, 50%) var(--my, -25%),
    rgba(18, 122, 110, 0.07),
    transparent 62%
  );
  opacity: 0;
  transition: opacity 0.4s;
  pointer-events: none;
}
:is(.card, .step-card, .list-card, .ver, .fit-card):hover::after {
  opacity: 1;
}

/* border beam — featured version card only */
.ver.primary .beam {
  position: absolute;
  inset: -75%;
  z-index: 0;
  background: conic-gradient(
    from 0deg,
    transparent 0 64%,
    rgba(18, 122, 110, 0.6) 78%,
    rgba(150, 240, 228, 0.95) 83%,
    rgba(18, 122, 110, 0.6) 88%,
    transparent 100%
  );
  animation: beamSpin 7s linear infinite;
}
.ver.primary::before {
  content: "";
  position: absolute;
  inset: 1px;
  z-index: 1;
  border-radius: calc(var(--r-lg) - 1px);
  background: var(--card);
  top: 1px;
  left: 1px;
  right: 1px;
  bottom: 1px;
  height: auto;
  opacity: 1;
}
.ver.primary > *:not(.beam) {
  position: relative;
  z-index: 2;
}
.ver.primary::after {
  z-index: 3;
}
@keyframes beamSpin {
  to {
    transform: rotate(1turn);
  }
}

@media (prefers-reduced-motion: reduce) {
  *,
  *::before,
  *::after {
    animation-duration: 0.01ms !important;
    animation-iteration-count: 1 !important;
    transition-duration: 0.01ms !important;
    scroll-behavior: auto !important;
  }
  .reveal {
    opacity: 1;
    transform: none;
  }
  .hero-title .line > span {
    transform: none;
  }
  /* un-pin the flow and show everything statically */
  .flow-pin {
    height: auto;
  }
  .flow-sticky {
    position: static;
    min-height: 0;
    padding: 0;
  }
  .fstep {
    opacity: 1;
  }
  .flow-cols {
    grid-template-columns: 1fr;
  }
  .flow-stage {
    position: static;
    display: grid;
    gap: 20px;
    min-height: 0;
    margin-top: 40px;
  }
  .fvis {
    position: static;
    opacity: 1;
    transform: none;
  }
  .term-body p {
    opacity: 1;
    transform: none;
  }
}