/* ============================================================
   听语字幕 · 官网样式
   纯原生 CSS，无任何第三方依赖
   ============================================================ */

:root {
  --ink: #0F1F1C;
  --ink-2: #33544F;
  --muted: #6E8C87;
  --muted-2: #8CA7A2;
  --deep: #0C8C7D;
  --teal: #35D0BA;
  --teal-soft: #E4FAF5;
  --bg: #F7FBFA;
  --card: #FFFFFF;
  --line: #E2F0ED;
  --dark: #10131A;
  --dark-2: #171B24;
  --radius: 18px;
  --shadow-sm: 0 2px 10px rgba(18, 60, 54, .05);
  --shadow-md: 0 10px 30px rgba(18, 60, 54, .08);
  --shadow-lg: 0 30px 70px rgba(9, 30, 27, .16);
  --max: 1160px;
  --nav-h: 64px;
}

* { box-sizing: border-box; }

html {
  scroll-behavior: smooth;
  -webkit-text-size-adjust: 100%;
}

body {
  margin: 0;
  font-family: -apple-system, BlinkMacSystemFont, "HarmonyOS Sans SC", "PingFang SC",
    "Hiragino Sans GB", "Microsoft YaHei", "Source Han Sans SC", sans-serif;
  color: var(--ink);
  background: var(--bg);
  line-height: 1.75;
  -webkit-font-smoothing: antialiased;
}

img { max-width: 100%; display: block; border: 0; }

a {
  color: var(--deep);
  text-decoration: none;
  transition: color .2s ease;
}
a:hover { color: var(--teal); }

h1, h2, h3, h4 {
  margin: 0;
  line-height: 1.3;
  font-weight: 700;
  letter-spacing: -.01em;
}

p { margin: 0; }

ul { margin: 0; padding: 0; list-style: none; }

.wrap {
  width: 100%;
  max-width: var(--max);
  margin: 0 auto;
  padding: 0 22px;
}

/* ---------------- 顶部导航 ---------------- */

.nav {
  position: sticky;
  top: 0;
  z-index: 100;
  height: var(--nav-h);
  display: flex;
  align-items: center;
  background: rgba(247, 251, 250, .82);
  backdrop-filter: saturate(180%) blur(14px);
  -webkit-backdrop-filter: saturate(180%) blur(14px);
  border-bottom: 1px solid rgba(226, 240, 237, .9);
}

.nav .wrap {
  display: flex;
  align-items: center;
  gap: 14px;
}

.brand {
  display: flex;
  align-items: center;
  gap: 10px;
  color: var(--ink);
  font-weight: 700;
  font-size: 16px;
  letter-spacing: .02em;
}
.brand:hover { color: var(--ink); }

/* 品牌标记：字幕框 + 声波，纯 CSS 绘制 */
.logo {
  position: relative;
  width: 34px;
  height: 34px;
  border-radius: 10px;
  background: var(--dark);
  flex: 0 0 auto;
  display: flex;
  align-items: center;
  justify-content: center;
}
.logo-bars {
  display: flex;
  align-items: center;
  gap: 2px;
  height: 14px;
}
.logo-bars i {
  display: block;
  width: 3px;
  border-radius: 2px;
  background: var(--teal);
}
.logo-bars i:nth-child(1) { height: 8px; }
.logo-bars i:nth-child(2) { height: 14px; }
.logo-bars i:nth-child(3) { height: 8px; }

.brand-sub {
  font-size: 10px;
  font-weight: 500;
  color: var(--muted-2);
  letter-spacing: .16em;
  text-transform: uppercase;
  margin-top: -2px;
}

.nav-links {
  display: flex;
  align-items: center;
  gap: 26px;
  margin-left: auto;
}
.nav-links a {
  font-size: 14px;
  color: var(--ink-2);
  font-weight: 500;
}
.nav-links a:hover { color: var(--deep); }

.nav-cta {
  margin-left: 6px;
  padding: 9px 18px;
  border-radius: 999px;
  background: var(--dark);
  color: #fff !important;
  font-size: 14px;
  font-weight: 600;
  transition: transform .2s ease, box-shadow .2s ease, background .2s ease;
}
.nav-cta:hover {
  background: #000;
  transform: translateY(-1px);
  box-shadow: 0 8px 20px rgba(16, 19, 26, .22);
}

/* ---------------- 首屏 ---------------- */

.hero {
  position: relative;
  overflow: hidden;
  background: var(--dark);
  color: #fff;
  padding: 76px 0 84px;
}

.hero::before,
.hero::after {
  content: "";
  position: absolute;
  border-radius: 50%;
  pointer-events: none;
}
.hero::before {
  width: 620px;
  height: 620px;
  right: -180px;
  top: -240px;
  background: radial-gradient(circle, rgba(53, 208, 186, .22), rgba(53, 208, 186, 0) 68%);
}
.hero::after {
  width: 520px;
  height: 520px;
  left: -200px;
  bottom: -260px;
  background: radial-gradient(circle, rgba(12, 140, 125, .18), rgba(12, 140, 125, 0) 70%);
}

.hero .wrap {
  position: relative;
  z-index: 1;
  display: grid;
  grid-template-columns: 1.06fr .94fr;
  gap: 52px;
  align-items: center;
}

.eyebrow {
  display: inline-flex;
  align-items: center;
  gap: 8px;
  padding: 6px 14px;
  border-radius: 999px;
  background: rgba(53, 208, 186, .12);
  border: 1px solid rgba(53, 208, 186, .28);
  color: var(--teal);
  font-size: 12.5px;
  font-weight: 600;
  letter-spacing: .04em;
}
.eyebrow .dot {
  width: 6px;
  height: 6px;
  border-radius: 50%;
  background: var(--teal);
  box-shadow: 0 0 0 4px rgba(53, 208, 186, .18);
  animation: pulse 2.4s ease-in-out infinite;
}

.hero h1 {
  font-size: clamp(32px, 4.4vw, 54px);
  margin: 22px 0 0;
  letter-spacing: -.02em;
  line-height: 1.18;
}

.hero h1 em {
  font-style: normal;
  color: var(--teal);
}

.hero-sub {
  margin-top: 20px;
  font-size: 16.5px;
  color: #A9B7B4;
  max-width: 33em;
}
.hero-sub strong { color: #fff; font-weight: 600; }

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

.btn {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  gap: 8px;
  height: 50px;
  padding: 0 28px;
  border-radius: 999px;
  font-size: 15px;
  font-weight: 600;
  border: 1px solid transparent;
  cursor: pointer;
  transition: transform .2s ease, box-shadow .2s ease, background .2s ease, border-color .2s ease;
}

.btn-primary {
  background: var(--teal);
  color: #062A25;
  box-shadow: 0 12px 28px rgba(53, 208, 186, .28);
}
.btn-primary:hover {
  color: #062A25;
  transform: translateY(-2px);
  box-shadow: 0 16px 36px rgba(53, 208, 186, .36);
}

.btn-ghost {
  background: rgba(255, 255, 255, .06);
  border-color: rgba(255, 255, 255, .22);
  color: #fff;
}
.btn-ghost:hover {
  color: #fff;
  background: rgba(255, 255, 255, .12);
  transform: translateY(-2px);
}

.btn-outline {
  background: transparent;
  border-color: var(--line);
  color: var(--ink);
}
.btn-outline:hover {
  color: var(--deep);
  border-color: var(--teal);
  transform: translateY(-2px);
}

.hero-stats {
  display: flex;
  gap: 34px;
  margin-top: 42px;
  padding-top: 26px;
  border-top: 1px solid rgba(255, 255, 255, .1);
}
.hero-stats div { min-width: 78px; }
.hero-stats b {
  display: block;
  font-size: 24px;
  font-weight: 700;
  color: #fff;
  line-height: 1.2;
}
.hero-stats span {
  font-size: 12.5px;
  color: #7D8F8C;
}

/* ---------------- 手机样机 ---------------- */

.phone {
  position: relative;
  width: 100%;
  max-width: 296px;
  margin: 0 auto;
  padding: 11px;
  border-radius: 46px;
  background: linear-gradient(160deg, #2A303A 0%, #0B0D12 46%, #1B2029 100%);
  box-shadow:
    0 0 0 1px rgba(255, 255, 255, .07) inset,
    0 40px 80px rgba(0, 0, 0, .5),
    0 6px 18px rgba(0, 0, 0, .35);
  animation: float 7s ease-in-out infinite;
}

.phone::after {
  /* 灵动岛 */
  content: "";
  position: absolute;
  top: 22px;
  left: 50%;
  transform: translateX(-50%);
  width: 84px;
  height: 22px;
  border-radius: 999px;
  background: #05060A;
  z-index: 3;
  pointer-events: none;
}

.phone-screen {
  position: relative;
  border-radius: 36px;
  overflow: hidden;
  background: #F8FCFB;
  aspect-ratio: 1280 / 2832;
}

.phone-screen img {
  width: 100%;
  height: 100%;
  object-fit: cover;
  object-position: top center;
}

.phone-glow {
  position: absolute;
  inset: -8% -14%;
  z-index: -1;
  border-radius: 50%;
  background: radial-gradient(circle at 50% 40%, rgba(53, 208, 186, .34), rgba(53, 208, 186, 0) 62%);
  filter: blur(6px);
}

.hero-phone { position: relative; }

/* 声波动画（首屏右侧底部装饰） */
.soundwave {
  display: flex;
  align-items: flex-end;
  justify-content: center;
  gap: 4px;
  height: 26px;
  margin-top: 22px;
}
.soundwave i {
  width: 4px;
  border-radius: 3px;
  background: rgba(53, 208, 186, .7);
  animation: wave 1.4s ease-in-out infinite;
}
.soundwave i:nth-child(1) { height: 8px;  animation-delay: 0s; }
.soundwave i:nth-child(2) { height: 15px; animation-delay: .12s; }
.soundwave i:nth-child(3) { height: 22px; animation-delay: .24s; }
.soundwave i:nth-child(4) { height: 13px; animation-delay: .36s; }
.soundwave i:nth-child(5) { height: 7px;  animation-delay: .48s; }

/* ---------------- 通用区块 ---------------- */

.section {
  padding: 84px 0;
}
.section.tight { padding: 62px 0; }
.section.dark {
  background: var(--dark);
  color: #fff;
}
.section.alt {
  background: #fff;
}

.sec-head {
  max-width: 660px;
  margin: 0 auto 46px;
  text-align: center;
}
.sec-tag {
  display: inline-block;
  font-size: 12px;
  font-weight: 700;
  letter-spacing: .18em;
  color: var(--deep);
  text-transform: uppercase;
  margin-bottom: 12px;
}
.section.dark .sec-tag { color: var(--teal); }

.sec-head h2 {
  font-size: clamp(24px, 3vw, 36px);
  letter-spacing: -.02em;
}
.sec-head p {
  margin-top: 14px;
  color: var(--muted);
  font-size: 15.5px;
}
.section.dark .sec-head p { color: #93A5A2; }

/* ---------------- 特点卡片 ---------------- */

.features {
  display: grid;
  grid-template-columns: repeat(3, 1fr);
  gap: 18px;
}

.card {
  position: relative;
  background: var(--card);
  border: 1px solid var(--line);
  border-radius: var(--radius);
  padding: 26px 24px 24px;
  box-shadow: var(--shadow-sm);
  transition: transform .28s cubic-bezier(.2, .8, .3, 1), box-shadow .28s ease, border-color .28s ease;
  overflow: hidden;
}

.card::before {
  content: "";
  position: absolute;
  inset: 0 0 auto 0;
  height: 2px;
  background: linear-gradient(90deg, var(--teal), rgba(53, 208, 186, 0));
  opacity: 0;
  transition: opacity .28s ease;
}

.card:hover {
  transform: translateY(-5px);
  box-shadow: var(--shadow-md);
  border-color: rgba(53, 208, 186, .45);
}
.card:hover::before { opacity: 1; }

.card-icon {
  width: 44px;
  height: 44px;
  border-radius: 13px;
  background: var(--teal-soft);
  display: flex;
  align-items: center;
  justify-content: center;
  margin-bottom: 16px;
  transition: transform .28s ease;
}
.card:hover .card-icon { transform: scale(1.06) rotate(-3deg); }

.card-icon svg { width: 22px; height: 22px; }

.card h3 {
  font-size: 17px;
  margin-bottom: 9px;
}
.card p {
  font-size: 14px;
  color: var(--muted);
  line-height: 1.72;
}

.card-highlight {
  background: linear-gradient(150deg, #0C8C7D, #0A6E63);
  border-color: transparent;
  color: #fff;
}
.card-highlight h3 { color: #fff; }
.card-highlight p { color: rgba(255, 255, 255, .78); }
.card-highlight .card-icon { background: rgba(255, 255, 255, .16); }
.card-highlight .card-icon svg { stroke: #fff; }
.card-highlight::before { display: none; }
.card-highlight:hover {
  border-color: transparent;
  box-shadow: 0 18px 44px rgba(12, 140, 125, .34);
}

/* ---------------- 场景 ---------------- */

.scenes {
  display: grid;
  grid-template-columns: repeat(5, 1fr);
  gap: 14px;
}
.scene {
  background: rgba(255, 255, 255, .04);
  border: 1px solid rgba(255, 255, 255, .09);
  border-radius: 16px;
  padding: 22px 18px;
  transition: background .25s ease, border-color .25s ease, transform .25s ease;
}
.scene:hover {
  background: rgba(53, 208, 186, .09);
  border-color: rgba(53, 208, 186, .34);
  transform: translateY(-4px);
}
.scene svg { width: 24px; height: 24px; margin-bottom: 12px; }
.scene h4 {
  font-size: 14.5px;
  color: #fff;
  margin-bottom: 6px;
}
.scene p {
  font-size: 12.5px;
  color: #829491;
  line-height: 1.62;
}

/* ---------------- 界面展示 ---------------- */

.gallery {
  display: flex;
  gap: 26px;
  overflow-x: auto;
  padding: 10px 22px 34px;
  scroll-snap-type: x mandatory;
  scrollbar-width: thin;
  -webkit-overflow-scrolling: touch;
}
.gallery::-webkit-scrollbar { height: 6px; }
.gallery::-webkit-scrollbar-thumb {
  background: rgba(53, 208, 186, .4);
  border-radius: 999px;
}
.gallery::-webkit-scrollbar-track { background: transparent; }

.shot {
  flex: 0 0 auto;
  width: 236px;
  scroll-snap-align: center;
}

.shot .phone {
  max-width: 100%;
  padding: 8px;
  border-radius: 38px;
  animation: none;
  transition: transform .3s ease, box-shadow .3s ease;
}
.shot .phone::after { width: 66px; height: 17px; top: 17px; }
.shot .phone-screen { border-radius: 30px; }
.shot:hover .phone {
  transform: translateY(-8px) scale(1.02);
  box-shadow: 0 0 0 1px rgba(255, 255, 255, .1) inset, 0 46px 80px rgba(0, 0, 0, .55);
}

.shot figcaption {
  margin-top: 14px;
  text-align: center;
  font-size: 13px;
  color: var(--muted);
  line-height: 1.5;
}
.shot figcaption b {
  display: block;
  color: var(--ink);
  font-size: 13.5px;
  font-weight: 600;
  margin-bottom: 2px;
}

.gallery-hint {
  text-align: center;
  font-size: 12.5px;
  color: var(--muted-2);
  margin-top: -12px;
}

/* ---------------- 模型表 ---------------- */

.models {
  display: grid;
  grid-template-columns: repeat(5, 1fr);
  gap: 14px;
}

.model {
  position: relative;
  background: var(--card);
  border: 1px solid var(--line);
  border-radius: 16px;
  padding: 20px 18px;
  transition: transform .25s ease, box-shadow .25s ease, border-color .25s ease;
}
.model:hover {
  transform: translateY(-4px);
  border-color: rgba(53, 208, 186, .5);
  box-shadow: var(--shadow-md);
}
.model .tag {
  position: absolute;
  top: 14px;
  right: 14px;
  font-size: 10px;
  font-weight: 700;
  padding: 2px 7px;
  border-radius: 6px;
  background: var(--teal-soft);
  color: var(--deep);
}
.model h4 { font-size: 15px; margin-bottom: 8px; }
.model dl {
  margin: 0;
  font-size: 12.5px;
  color: var(--muted);
  line-height: 1.9;
}
.model dl div {
  display: flex;
  justify-content: space-between;
  gap: 8px;
  border-top: 1px dashed var(--line);
  padding-top: 4px;
  margin-top: 4px;
}
.model dt { color: var(--muted-2); }
.model dd { margin: 0; color: var(--ink-2); font-weight: 500; }

/* ---------------- 隐私承诺 ---------------- */

.pledges {
  display: grid;
  grid-template-columns: repeat(2, 1fr);
  gap: 16px;
}
.pledge {
  display: flex;
  gap: 16px;
  padding: 24px;
  border-radius: 16px;
  background: rgba(255, 255, 255, .04);
  border: 1px solid rgba(255, 255, 255, .08);
  transition: background .25s ease, border-color .25s ease;
}
.pledge:hover {
  background: rgba(53, 208, 186, .08);
  border-color: rgba(53, 208, 186, .3);
}
.pledge-num {
  flex: 0 0 auto;
  width: 34px;
  height: 34px;
  border-radius: 10px;
  background: rgba(53, 208, 186, .16);
  color: var(--teal);
  display: flex;
  align-items: center;
  justify-content: center;
  font-size: 13px;
  font-weight: 700;
}
.pledge h4 { color: #fff; font-size: 15.5px; margin-bottom: 6px; }
.pledge p { font-size: 13.5px; color: #8FA2A0; line-height: 1.7; }

/* ---------------- 下载 ---------------- */

.download {
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: 34px;
  align-items: center;
}

.dl-panel {
  background: var(--card);
  border: 1px solid var(--line);
  border-radius: 22px;
  padding: 30px;
  box-shadow: var(--shadow-md);
}

.tabs {
  display: flex;
  gap: 6px;
  padding: 5px;
  background: #EEF6F4;
  border-radius: 999px;
  margin-bottom: 22px;
}
.tabs button {
  flex: 1;
  border: 0;
  background: transparent;
  padding: 10px 8px;
  border-radius: 999px;
  font-size: 13.5px;
  font-weight: 600;
  color: var(--muted);
  font-family: inherit;
  cursor: pointer;
  transition: background .22s ease, color .22s ease, box-shadow .22s ease;
}
.tabs button[aria-selected="true"] {
  background: #fff;
  color: var(--ink);
  box-shadow: 0 2px 8px rgba(18, 60, 54, .1);
}

.tab-body { display: none; }
.tab-body.active { display: block; animation: fadeIn .35s ease both; }

.dl-ver {
  display: flex;
  align-items: baseline;
  gap: 10px;
  margin-bottom: 6px;
}
.dl-ver b { font-size: 26px; font-weight: 700; }
.dl-ver span { font-size: 12.5px; color: var(--muted-2); }

.dl-note {
  font-size: 13.5px;
  color: var(--muted);
  margin-bottom: 18px;
}

.dl-steps {
  counter-reset: st;
  margin-bottom: 22px;
}
.dl-steps li {
  position: relative;
  padding-left: 30px;
  font-size: 13.5px;
  color: var(--ink-2);
  margin-bottom: 10px;
  counter-increment: st;
}
.dl-steps li::before {
  content: counter(st);
  position: absolute;
  left: 0;
  top: 3px;
  width: 20px;
  height: 20px;
  border-radius: 50%;
  background: var(--teal-soft);
  color: var(--deep);
  font-size: 11px;
  font-weight: 700;
  display: flex;
  align-items: center;
  justify-content: center;
}

.dl-qr {
  display: flex;
  align-items: center;
  gap: 16px;
  padding: 16px;
  border-radius: 14px;
  background: #F6FBF9;
  border: 1px dashed #C9E4DF;
}
.dl-qr-box {
  flex: 0 0 auto;
  width: 78px;
  height: 78px;
  border-radius: 10px;
  background: #fff;
  border: 1px solid var(--line);
  display: flex;
  align-items: center;
  justify-content: center;
  color: var(--muted-2);
  font-size: 10.5px;
  text-align: center;
  line-height: 1.4;
  padding: 4px;
}
.dl-qr p {
  font-size: 12.5px;
  color: var(--muted);
  line-height: 1.62;
}
.dl-qr p b { color: var(--ink-2); }

.dl-aside h3 {
  font-size: clamp(22px, 2.6vw, 30px);
  margin-bottom: 14px;
}
.dl-aside > p {
  color: var(--muted);
  font-size: 15px;
  margin-bottom: 22px;
}

.spec {
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: 12px;
}
.spec div {
  background: #fff;
  border: 1px solid var(--line);
  border-radius: 13px;
  padding: 14px 16px;
}
.spec b { display: block; font-size: 18px; }
.spec span { font-size: 12.5px; color: var(--muted-2); }

/* ---------------- 联系方式 ---------------- */

.contacts {
  display: grid;
  grid-template-columns: repeat(4, 1fr);
  gap: 14px;
}
.contact {
  background: #fff;
  border: 1px solid var(--line);
  border-radius: 16px;
  padding: 22px;
  transition: transform .25s ease, box-shadow .25s ease, border-color .25s ease;
}
.contact:hover {
  transform: translateY(-4px);
  border-color: rgba(53, 208, 186, .45);
  box-shadow: var(--shadow-md);
}
.contact .k {
  font-size: 12px;
  color: var(--muted-2);
  margin-bottom: 8px;
  letter-spacing: .04em;
}
.contact .v {
  font-size: 15px;
  font-weight: 600;
  color: var(--ink);
  word-break: break-all;
}
.contact .v small {
  display: block;
  font-size: 11.5px;
  font-weight: 400;
  color: var(--muted-2);
  margin-top: 4px;
}

/* ---------------- FAQ ---------------- */

.faq {
  max-width: 800px;
  margin: 0 auto;
}
.faq details {
  background: #fff;
  border: 1px solid var(--line);
  border-radius: 14px;
  padding: 4px 22px;
  margin-bottom: 12px;
  transition: border-color .22s ease, box-shadow .22s ease;
}
.faq details[open] {
  border-color: rgba(53, 208, 186, .5);
  box-shadow: var(--shadow-sm);
}
.faq summary {
  cursor: pointer;
  padding: 16px 0;
  font-size: 15px;
  font-weight: 600;
  list-style: none;
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 12px;
}
.faq summary::-webkit-details-marker { display: none; }
.faq summary::after {
  content: "+";
  flex: 0 0 auto;
  width: 22px;
  height: 22px;
  border-radius: 50%;
  background: var(--teal-soft);
  color: var(--deep);
  font-size: 15px;
  font-weight: 700;
  display: flex;
  align-items: center;
  justify-content: center;
  transition: transform .22s ease;
}
.faq details[open] summary::after { transform: rotate(45deg); }
.faq .a {
  padding-bottom: 18px;
  font-size: 14px;
  color: var(--muted);
  line-height: 1.78;
}
.faq .a p + p { margin-top: 8px; }

/* ---------------- 页脚 ---------------- */

.footer {
  background: var(--dark);
  color: #8FA2A0;
  padding: 54px 0 30px;
  font-size: 13px;
}
.footer a { color: #A9B7B4; }
.footer a:hover { color: var(--teal); }

.footer-top {
  display: grid;
  grid-template-columns: 1.4fr 1fr 1fr 1fr;
  gap: 30px;
  padding-bottom: 34px;
  border-bottom: 1px solid rgba(255, 255, 255, .08);
}
.footer-brand { display: flex; align-items: center; gap: 12px; margin-bottom: 14px; }
.footer-brand b { color: #fff; font-size: 15px; }
.footer-brand span {
  display: block;
  font-size: 10px;
  letter-spacing: .16em;
  color: #6E8C87;
}
.footer h4 {
  color: #fff;
  font-size: 13.5px;
  margin-bottom: 12px;
  letter-spacing: .04em;
}
.footer li { margin-bottom: 8px; }

.footer-bottom {
  padding-top: 22px;
  display: flex;
  flex-wrap: wrap;
  gap: 8px 20px;
  align-items: center;
  justify-content: space-between;
  font-size: 12px;
  color: #6E8C87;
}

/* ---------------- 子页面（文档） ---------------- */

.doc-hero {
  background: var(--dark);
  color: #fff;
  padding: 58px 0 54px;
}
.doc-hero h1 {
  font-size: clamp(26px, 3.4vw, 38px);
}
.doc-hero p {
  margin-top: 14px;
  color: #93A5A2;
  font-size: 15px;
  max-width: 46em;
}
.doc-meta {
  display: inline-flex;
  gap: 14px;
  margin-top: 18px;
  font-size: 12.5px;
  color: #6E8C87;
}

.doc-body {
  padding: 46px 0 70px;
}
.doc-layout {
  display: grid;
  grid-template-columns: 210px 1fr;
  gap: 40px;
  align-items: start;
}

.toc {
  position: sticky;
  top: calc(var(--nav-h) + 24px);
  background: #fff;
  border: 1px solid var(--line);
  border-radius: 14px;
  padding: 18px;
  font-size: 13px;
}
.toc b {
  display: block;
  font-size: 12px;
  color: var(--muted-2);
  letter-spacing: .1em;
  margin-bottom: 10px;
  text-transform: uppercase;
}
.toc a {
  display: block;
  padding: 6px 0;
  color: var(--ink-2);
  border-left: 2px solid transparent;
  padding-left: 10px;
  margin-left: -10px;
  transition: color .2s ease, border-color .2s ease;
}
.toc a:hover,
.toc a.on {
  color: var(--deep);
  border-left-color: var(--teal);
}

.article {
  max-width: 780px;
}
.article section {
  margin-bottom: 34px;
  scroll-margin-top: calc(var(--nav-h) + 20px);
}
.article h2 {
  font-size: 19px;
  margin-bottom: 12px;
  padding-left: 12px;
  border-left: 3px solid var(--teal);
  line-height: 1.4;
}
.article p {
  font-size: 14.5px;
  color: var(--ink-2);
  line-height: 1.9;
  margin-bottom: 10px;
}
.article ul { margin: 8px 0 12px; }
.article li {
  position: relative;
  padding-left: 18px;
  font-size: 14.5px;
  color: var(--ink-2);
  line-height: 1.9;
  margin-bottom: 6px;
}
.article li::before {
  content: "";
  position: absolute;
  left: 2px;
  top: 12px;
  width: 5px;
  height: 5px;
  border-radius: 50%;
  background: var(--teal);
}
.article .callout {
  background: var(--teal-soft);
  border-radius: 12px;
  padding: 16px 18px;
  font-size: 13.5px;
  color: var(--deep);
  line-height: 1.75;
  margin: 14px 0;
}

/* ---------------- 动效 ---------------- */

/* 只有 JS 可用时才隐藏待进场元素：禁用 JS 或爬虫抓取时内容照常可见 */
.js .reveal {
  opacity: 0;
  transform: translateY(20px);
  transition: opacity .7s cubic-bezier(.2, .8, .3, 1), transform .7s cubic-bezier(.2, .8, .3, 1);
  will-change: opacity, transform;
}
.js .reveal.in {
  opacity: 1;
  transform: none;
}

@keyframes float {
  0%, 100% { transform: translateY(0); }
  50% { transform: translateY(-12px); }
}

@keyframes wave {
  0%, 100% { transform: scaleY(.55); opacity: .55; }
  50% { transform: scaleY(1); opacity: 1; }
}

@keyframes pulse {
  0%, 100% { box-shadow: 0 0 0 3px rgba(53, 208, 186, .16); }
  50% { box-shadow: 0 0 0 7px rgba(53, 208, 186, .06); }
}

@keyframes fadeIn {
  from { opacity: 0; transform: translateY(8px); }
  to { opacity: 1; transform: none; }
}

@media (prefers-reduced-motion: reduce) {
  html { scroll-behavior: auto; }
  *, *::before, *::after {
    animation-duration: .001ms !important;
    animation-iteration-count: 1 !important;
    transition-duration: .001ms !important;
  }
  .reveal { opacity: 1; transform: none; }
  .js .reveal { opacity: 1; transform: none; }
}

/* ---------------- 响应式 ---------------- */

@media (max-width: 1020px) {
  .hero .wrap {
    grid-template-columns: 1fr;
    gap: 46px;
    text-align: center;
  }
  .hero-sub { margin-left: auto; margin-right: auto; }
  .hero-actions { justify-content: center; }
  .hero-stats { justify-content: center; }
  .hero-phone { order: -1; }
  .phone { max-width: 262px; }

  .features { grid-template-columns: repeat(2, 1fr); }
  .scenes { grid-template-columns: repeat(3, 1fr); }
  .models { grid-template-columns: repeat(2, 1fr); }
  .contacts { grid-template-columns: repeat(2, 1fr); }
  .download { grid-template-columns: 1fr; }
  .dl-aside { order: -1; }
  .footer-top { grid-template-columns: 1fr 1fr; }
  .doc-layout { grid-template-columns: 1fr; }
  .toc { position: static; }
}

@media (max-width: 720px) {
  :root { --nav-h: 58px; }

  .wrap { padding: 0 18px; }

  .nav-links { gap: 16px; }
  .nav-links a:not(.nav-cta) { display: none; }

  .hero { padding: 48px 0 60px; }
  .hero h1 { font-size: 30px; }
  .hero-sub { font-size: 15px; }
  .hero-stats { gap: 22px; flex-wrap: wrap; }
  .hero-stats b { font-size: 20px; }
  .phone { max-width: 232px; }

  .section { padding: 58px 0; }
  .section.tight { padding: 44px 0; }
  .sec-head { margin-bottom: 32px; }
  .sec-head h2 { font-size: 23px; }
  .sec-head p { font-size: 14px; }

  .features { grid-template-columns: 1fr; gap: 14px; }
  .card { padding: 22px 20px; }
  .scenes { grid-template-columns: 1fr 1fr; }
  .models { grid-template-columns: 1fr; }
  .pledges { grid-template-columns: 1fr; }
  .contacts { grid-template-columns: 1fr; }
  .spec { grid-template-columns: 1fr 1fr; }

  .gallery { gap: 18px; padding: 6px 18px 28px; }
  .shot { width: 200px; }

  .dl-panel { padding: 22px 18px; }
  .btn { height: 46px; padding: 0 22px; font-size: 14px; }
  .hero-actions .btn { flex: 1 1 auto; }

  .footer { padding: 40px 0 26px; }
  .footer-top { grid-template-columns: 1fr; gap: 24px; }
  .footer-bottom { justify-content: flex-start; }

  .doc-hero { padding: 40px 0 38px; }
  .doc-body { padding: 30px 0 50px; }
}

@media (max-width: 380px) {
  .scenes { grid-template-columns: 1fr; }
  .spec { grid-template-columns: 1fr; }
}