/* =========================================================
   冷狐宝盒 · 落地页样式
   配色取自 logo：石墨灰（毛衣）、银灰（发色/爪印）、暖棕（眼瞳）
   设计基调：浅色高级灰底 + 深色信息块，克制的层级与大留白
   ========================================================= */

:root {
  /* —— 取自 logo 的配色 —— */
  --brand: #3d444b;          /* 主色：石墨灰（毛衣色） */
  --brand-dark: #23282d;     /* 深色：用于下载区块 */
  --brand-soft: #5b636b;     /* 次级石墨灰 */
  --silver: #cfd5db;         /* 辅助色：银灰（发色 / 爪印） */
  --silver-soft: #e8ecef;    /* 银灰浅调 */
  --accent: #9a6047;         /* 点缀色：暖棕（眼瞳） */
  --accent-soft: #f2e9e4;    /* 暖棕浅调 */

  /* —— 中性色 —— */
  --bg: #f6f7f8;
  --surface: #ffffff;
  --text: #1d2125;
  --text-muted: #6b737b;
  --text-light: #9aa3ab;
  --line: #e4e8eb;
  --line-strong: #d3d9de;

  /* —— 尺度 —— */
  --container: 1200px;
  --header-h: 76px;
  --radius-s: 10px;
  --radius: 16px;
  --radius-l: 24px;
  --radius-xl: 28px;

  /* —— 阴影 —— */
  --shadow-s: 0 1px 2px rgba(29, 33, 37, .05), 0 10px 24px -18px rgba(29, 33, 37, .35);
  --shadow-m: 0 2px 6px rgba(29, 33, 37, .05), 0 28px 56px -34px rgba(29, 33, 37, .45);

  /* —— 字体与动效 —— */
  --font: -apple-system, BlinkMacSystemFont, "PingFang SC", "Microsoft YaHei", "Segoe UI", sans-serif;
  --ease: cubic-bezier(.22, .61, .36, 1);
}

/* ------------------------- 基础 ------------------------- */
*,
*::before,
*::after { box-sizing: border-box; }

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

body {
  margin: 0;
  font-family: var(--font);
  font-size: 16px;
  line-height: 1.7;
  color: var(--text);
  background: var(--bg);
  -webkit-font-smoothing: antialiased;
  -moz-osx-font-smoothing: grayscale;
}

h1, h2, h3, p, ul { margin: 0; }
ul { list-style: none; padding: 0; }
img { display: block; max-width: 100%; }
a { color: inherit; text-decoration: none; }
button { font: inherit; color: inherit; }

h1, h2, h3 { letter-spacing: -.02em; line-height: 1.2; }

/* 锚点定位时避开吸顶导航，防止标题被遮挡 */
[id] { scroll-margin-top: calc(var(--header-h) + 16px); }

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

.skip-link {
  position: fixed;
  top: 12px;
  left: -9999px;
  z-index: 300;
  padding: 10px 18px;
  border-radius: 999px;
  background: var(--brand);
  color: #fff;
  font-size: 14px;
  transition: left .2s var(--ease);
}
.skip-link:focus { left: 16px; }

/* 图片占位：src 为空时不显示破图图标，由父容器提供低调底色与文字占位 */
img[src=""],
img:not([src]) { opacity: 0; }

/* ------------------------- 通用 ------------------------- */
.container {
  width: 100%;
  max-width: var(--container);
  margin-inline: auto;
  padding-inline: clamp(20px, 4vw, 40px);
}

.btn {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  gap: 8px;
  padding: 11px 20px;
  border-radius: 999px;
  border: 1px solid transparent;
  font-size: 14.5px;
  font-weight: 600;
  letter-spacing: .01em;
  cursor: pointer;
  white-space: nowrap;
  transition: background .28s var(--ease), color .28s var(--ease), border-color .28s var(--ease), transform .28s var(--ease), box-shadow .28s var(--ease);
}

.btn--primary {
  background: var(--brand);
  color: #fff;
  box-shadow: 0 10px 24px -14px rgba(35, 40, 45, .7);
}
.btn--primary:hover { background: var(--brand-dark); transform: translateY(-1px); }
.btn--primary:active { transform: translateY(1px); box-shadow: 0 2px 6px -3px rgba(35, 40, 45, .6); }

.btn--ghost {
  background: transparent;
  border-color: var(--line-strong);
  color: var(--text);
}
.btn--ghost:hover { background: #fff; border-color: var(--brand-soft); transform: translateY(-1px); }

.btn--lg { padding: 15px 28px; font-size: 15.5px; }
.btn__icon { flex: 0 0 auto; }

.link-arrow {
  position: relative;
  font-size: 14.5px;
  font-weight: 500;
  color: var(--brand);
  padding-bottom: 2px;
}
.link-arrow::after {
  content: "";
  position: absolute;
  left: 0;
  bottom: 0;
  width: 100%;
  height: 1px;
  background: currentColor;
  transform: scaleX(.4);
  transform-origin: left;
  opacity: .45;
  transition: transform .35s var(--ease), opacity .35s var(--ease);
}
.link-arrow:hover::after { transform: scaleX(1); opacity: .9; }

.kicker {
  display: inline-block;
  font-size: 11px;
  font-weight: 600;
  letter-spacing: .22em;
  text-transform: uppercase;
  color: var(--text-light);
}
.kicker--light { color: rgba(255, 255, 255, .58); }

.section {
  padding-block: clamp(64px, 7vw, 112px);
  border-bottom: 1px solid var(--line);
}

.section-head { max-width: 740px; margin-bottom: clamp(34px, 4vw, 58px); }
.section-title {
  margin-top: 14px;
  font-size: clamp(1.85rem, 3vw, 2.7rem);
  font-weight: 600;
  line-height: 1.24;
}
.section-desc {
  margin-top: 16px;
  max-width: 58ch;
  font-size: 15.5px;
  color: var(--text-muted);
}
.section-desc strong { color: var(--text); font-weight: 600; }

/* 滚动淡入（用 translate 独立属性，避免覆盖卡片 hover 的 transform） */
.reveal {
  opacity: 0;
  translate: 0 18px;
  transition: opacity .8s var(--ease) var(--reveal-delay, 0ms),
              translate .8s var(--ease) var(--reveal-delay, 0ms);
}
.reveal.is-visible { opacity: 1; translate: 0 0; }

/* ------------------------- 顶部导航 ------------------------- */
.site-header {
  position: sticky;
  top: 0;
  z-index: 100;
  background: rgba(246, 247, 248, .8);
  -webkit-backdrop-filter: saturate(150%) blur(14px);
  backdrop-filter: saturate(150%) blur(14px);
  border-bottom: 1px solid transparent;
  transition: border-color .3s var(--ease), box-shadow .3s var(--ease), background .3s var(--ease);
}
.site-header.is-scrolled {
  border-bottom-color: var(--line);
  box-shadow: 0 12px 32px -28px rgba(29, 33, 37, .6);
  background: rgba(246, 247, 248, .92);
}

.header-inner {
  position: relative;
  display: flex;
  align-items: center;
  gap: 28px;
  min-height: var(--header-h);
}

.brand {
  display: inline-flex;
  align-items: center;
  gap: 12px;
  flex: 0 0 auto;
}
.logo-badge {
  position: relative;
  display: grid;
  place-items: center;
  width: 42px;
  height: 42px;
  border-radius: 13px;
  overflow: hidden;
  background: linear-gradient(145deg, #4f575f, #262b30);
  box-shadow: 0 8px 18px -12px rgba(35, 40, 45, .9);
  flex: 0 0 auto;
}
.logo-badge img {
  position: absolute;
  inset: 0;
  width: 100%;
  height: 100%;
  object-fit: cover;
}
.logo-fallback {
  font-size: 15px;
  font-weight: 600;
  letter-spacing: .04em;
  color: rgba(255, 255, 255, .9);
}
.logo-badge--sm { width: 36px; height: 36px; border-radius: 11px; }

.brand-text { display: flex; flex-direction: column; line-height: 1.1; }
.brand-name { font-size: 16px; font-weight: 600; letter-spacing: .02em; }
.brand-sub {
  margin-top: 4px;
  font-size: 9.5px;
  letter-spacing: .18em;
  text-transform: uppercase;
  color: var(--text-light);
}

.nav {
  display: flex;
  align-items: center;
  gap: 2px;
  margin-left: auto;
}
.nav a {
  padding: 8px 14px;
  border-radius: 8px;
  font-size: 14.5px;
  color: #4a525a;
  transition: color .25s var(--ease), background .25s var(--ease);
}
.nav a:hover { color: var(--text); background: rgba(61, 68, 75, .06); }

.header-actions { display: flex; align-items: center; gap: 12px; flex: 0 0 auto; }

.nav-toggle {
  display: none;
  place-items: center;
  width: 42px;
  height: 42px;
  padding: 0;
  border-radius: 12px;
  border: 1px solid var(--line-strong);
  background: rgba(255, 255, 255, .72);
  cursor: pointer;
}
.nav-toggle__bars { position: relative; display: block; width: 18px; height: 12px; }
.nav-toggle__bars i {
  position: absolute;
  left: 0;
  width: 18px;
  height: 1.5px;
  border-radius: 2px;
  background: var(--brand);
  transition: transform .35s var(--ease), opacity .25s var(--ease);
}
.nav-toggle__bars i:nth-child(1) { top: 0; }
.nav-toggle__bars i:nth-child(2) { top: 5.25px; }
.nav-toggle__bars i:nth-child(3) { top: 10.5px; }
.nav-toggle[aria-expanded="true"] .nav-toggle__bars i:nth-child(1) { transform: translateY(5.25px) rotate(45deg); }
.nav-toggle[aria-expanded="true"] .nav-toggle__bars i:nth-child(2) { opacity: 0; }
.nav-toggle[aria-expanded="true"] .nav-toggle__bars i:nth-child(3) { transform: translateY(-5.25px) rotate(-45deg); }

/* ------------------------- 首屏 ------------------------- */
.hero {
  position: relative;
  padding-block: clamp(30px, 4.2vw, 60px);
  border-bottom: 1px solid var(--line);
}
.hero::before {
  content: "";
  position: absolute;
  inset: 0;
  pointer-events: none;
  background:
    radial-gradient(900px 540px at 76% -18%, rgba(61, 68, 75, .13), transparent 62%),
    radial-gradient(620px 460px at 2% 18%, rgba(154, 96, 71, .06), transparent 66%);
}

.hero-grid {
  position: relative;
  display: grid;
  grid-template-columns: minmax(0, 1.06fr) minmax(0, .94fr);
  align-items: center;
  gap: clamp(28px, 4.5vw, 64px);
}

.hero-copy { max-width: 640px; }

.eyebrow {
  display: inline-flex;
  align-items: center;
  gap: 9px;
  font-size: 11.5px;
  font-weight: 600;
  letter-spacing: .16em;
  text-transform: uppercase;
  color: var(--text-muted);
}
.pulse {
  width: 6px;
  height: 6px;
  border-radius: 50%;
  background: var(--accent);
  box-shadow: 0 0 0 4px rgba(154, 96, 71, .12);
}

.hero-title {
  margin-top: 18px;
  font-size: clamp(2.9rem, 5.1vw, 4.2rem);
  font-weight: 600;
  letter-spacing: -.035em;
  line-height: 1.04;
}
.hero-title__sub {
  display: block;
  margin-top: 16px;
  font-size: clamp(1.22rem, 1.9vw, 1.6rem);
  font-weight: 500;
  letter-spacing: -.01em;
  line-height: 1.42;
  color: #4c545c;
}

.lede {
  margin-top: 22px;
  max-width: 46ch;
  font-size: 16px;
  line-height: 1.82;
  color: var(--text-muted);
}

.hero-tags {
  display: flex;
  flex-wrap: wrap;
  gap: 8px;
  margin-top: 22px;
}
.hero-tags li {
  display: inline-flex;
  align-items: center;
  gap: 7px;
  padding: 6px 13px;
  border: 1px solid var(--line-strong);
  border-radius: 999px;
  background: rgba(255, 255, 255, .66);
  font-size: 12.5px;
  color: #4c545c;
}
.hero-tags li::before {
  content: "";
  width: 4px;
  height: 4px;
  border-radius: 50%;
  background: var(--brand-soft);
}

.hero-cta {
  display: flex;
  align-items: center;
  flex-wrap: wrap;
  gap: 12px 22px;
  margin-top: 30px;
}

.meta-cards {
  display: grid;
  grid-template-columns: repeat(3, minmax(0, 1fr));
  gap: 10px;
  max-width: 478px;
  margin-top: 28px;
}
.meta-card {
  padding: 12px 14px;
  border: 1px solid var(--line);
  border-radius: var(--radius-s);
  background: rgba(255, 255, 255, .78);
  box-shadow: var(--shadow-s);
}
.meta-label {
  display: block;
  font-size: 10px;
  font-weight: 600;
  letter-spacing: .14em;
  text-transform: uppercase;
  color: var(--text-light);
}
.meta-value {
  display: block;
  margin-top: 5px;
  font-size: 15px;
  font-weight: 600;
  font-variant-numeric: tabular-nums;
  letter-spacing: -.01em;
  color: var(--text);
}

/* 截图叠放区 */
.hero-visual {
  position: relative;
  display: flex;
  flex-direction: column;
  align-items: center;
  gap: 20px;
  padding-block: 6px;
}

.shot-stage {
  position: relative;
  width: clamp(238px, 20vw, 300px);
  aspect-ratio: 9 / 17;
}

.shot {
  position: absolute;
  inset: 0;
  border-radius: var(--radius-xl);
  overflow: hidden;
  background: linear-gradient(165deg, #f2f4f6 0%, #e2e7ea 55%, #eceff2 100%);
  border: 1px solid var(--line-strong);
  box-shadow: var(--shadow-m);
  cursor: pointer;
  transition: transform .6s var(--ease), opacity .5s var(--ease), box-shadow .5s var(--ease);
  will-change: transform;
}

.shot.is-active {
  z-index: 3;
  opacity: 1;
  transform: translate3d(0, 0, 0) rotate(0) scale(1);
}
.shot.is-right {
  z-index: 2;
  opacity: .62;
  transform: translate3d(8.5%, 1.5%, 0) rotate(4deg) scale(.915);
}
.shot.is-left {
  z-index: 2;
  opacity: .62;
  transform: translate3d(-8.5%, 1.5%, 0) rotate(-4deg) scale(.915);
}

.shot img {
  position: absolute;
  inset: 0;
  width: 100%;
  height: 100%;
  object-fit: cover;
  z-index: 1;
}

.shot-ph {
  position: absolute;
  inset: 0;
  z-index: 0;
  display: flex;
  flex-direction: column;
  align-items: center;
  justify-content: center;
  gap: 7px;
  color: #8b949c;
  font-size: 13px;
  letter-spacing: .08em;
  text-align: center;
}
.shot-ph__num {
  font-size: 26px;
  font-weight: 600;
  letter-spacing: .02em;
  color: #a5adb4;
  font-variant-numeric: tabular-nums;
}
.shot-ph__hint {
  font-size: 10.5px;
  letter-spacing: .04em;
  color: #aeb6bd;
}

.shot-dots { display: flex; align-items: center; gap: 8px; }
.shot-dot {
  width: 44px;
  height: 32px;
  padding: 0;
  border: 1px solid var(--line-strong);
  border-radius: 999px;
  background: rgba(255, 255, 255, .8);
  color: var(--text-light);
  font-size: 11.5px;
  font-weight: 600;
  font-variant-numeric: tabular-nums;
  letter-spacing: .06em;
  cursor: pointer;
  transition: background .3s var(--ease), color .3s var(--ease), border-color .3s var(--ease), transform .3s var(--ease);
}
.shot-dot:hover { border-color: var(--brand-soft); color: var(--brand); }
.shot-dot.is-active {
  background: var(--brand);
  border-color: var(--brand);
  color: #fff;
  transform: translateY(-1px);
}

.shot-hint { font-size: 11.5px; color: var(--text-light); letter-spacing: .04em; }

/* ------------------------- 简介 ------------------------- */
.intro { background: var(--surface); }

.intro-grid {
  display: grid;
  grid-template-columns: minmax(0, 1fr) minmax(0, 1.12fr);
  gap: clamp(28px, 5vw, 80px);
  align-items: start;
}
.intro-lead .section-title { max-width: 22ch; }
.intro-body p {
  font-size: 15.5px;
  line-height: 1.9;
  color: var(--text-muted);
}
.intro-body p + p { margin-top: 16px; }

.stat-row {
  display: grid;
  grid-template-columns: repeat(3, minmax(0, 1fr));
  gap: 18px;
  margin-top: clamp(28px, 3vw, 40px);
  padding-top: clamp(24px, 2.6vw, 34px);
  border-top: 1px solid var(--line);
}
.stat-value {
  display: block;
  font-size: clamp(1.5rem, 2.2vw, 1.85rem);
  font-weight: 600;
  letter-spacing: -.02em;
  font-variant-numeric: tabular-nums;
  color: var(--brand);
  line-height: 1.2;
}
.stat-label {
  display: block;
  margin-top: 8px;
  font-size: 12.5px;
  line-height: 1.65;
  color: var(--text-muted);
}

/* ------------------------- 功能 ------------------------- */
.features { background: var(--bg); }

.feature-grid {
  display: grid;
  grid-template-columns: repeat(3, minmax(0, 1fr));
  gap: clamp(14px, 1.6vw, 22px);
}

.feature-card {
  position: relative;
  padding: clamp(22px, 2.2vw, 30px);
  border: 1px solid var(--line);
  border-radius: var(--radius);
  background: var(--surface);
  box-shadow: var(--shadow-s);
  transition: transform .35s var(--ease), box-shadow .35s var(--ease), border-color .35s var(--ease),
              opacity .8s var(--ease) var(--reveal-delay, 0ms), translate .8s var(--ease) var(--reveal-delay, 0ms);
}
.feature-card:hover {
  transform: translateY(-4px);
  border-color: var(--line-strong);
  box-shadow: var(--shadow-m);
}

.feature-icon {
  display: grid;
  place-items: center;
  width: 46px;
  height: 46px;
  margin-bottom: 22px;
  border-radius: 12px;
  background: linear-gradient(150deg, #eff2f4, #e1e6e9);
  color: var(--brand);
}
.feature-icon svg { width: 22px; height: 22px; }

.feature-index {
  position: absolute;
  top: clamp(24px, 2.4vw, 32px);
  right: clamp(24px, 2.4vw, 32px);
  font-size: 11px;
  font-weight: 600;
  letter-spacing: .1em;
  color: #b4bcc2;
  font-variant-numeric: tabular-nums;
}

.feature-card h3 { font-size: 18px; font-weight: 600; }
.feature-card p {
  margin-top: 10px;
  font-size: 14.5px;
  line-height: 1.8;
  color: var(--text-muted);
}

/* 卡片错峰入场 */
.feature-grid > .reveal:nth-child(3n + 2) { --reveal-delay: 70ms; }
.feature-grid > .reveal:nth-child(3n + 3) { --reveal-delay: 140ms; }

/* ------------------------- 评价 ------------------------- */
.reviews { background: var(--surface); }

.review-grid {
  display: grid;
  grid-template-columns: repeat(2, minmax(0, 1fr));
  gap: clamp(14px, 1.6vw, 20px);
}

.review-card {
  display: flex;
  flex-direction: column;
  gap: 16px;
  padding: clamp(22px, 2.4vw, 34px);
  border: 1px solid var(--line);
  border-radius: var(--radius);
  background: var(--bg);
  transition: border-color .3s var(--ease), box-shadow .3s var(--ease),
              opacity .8s var(--ease) var(--reveal-delay, 0ms), translate .8s var(--ease) var(--reveal-delay, 0ms);
}
.review-card:hover { border-color: var(--line-strong); box-shadow: var(--shadow-s); }

.review-stars {
  color: var(--accent);
  font-size: 13px;
  letter-spacing: .12em;
  line-height: 1;
}

.review-quote {
  font-size: 16px;
  line-height: 1.85;
  color: #2f353b;
}

.review-foot {
  display: flex;
  align-items: center;
  gap: 12px;
  margin-top: auto;
  padding-top: 18px;
  border-top: 1px solid var(--line);
}

/* 汉字头像：绝对不使用 img */
.avatar {
  display: grid;
  place-items: center;
  width: 42px;
  height: 42px;
  border-radius: 50%;
  flex: 0 0 auto;
  background: var(--brand);
  color: #fff;
  font-size: 16px;
  font-weight: 600;
  letter-spacing: .02em;
  user-select: none;
}
.review-grid > .review-card:nth-child(2) .avatar { background: var(--accent); }
.review-grid > .review-card:nth-child(3) .avatar { background: var(--brand-soft); }
.review-grid > .review-card:nth-child(4) .avatar { background: #6d757d; }

.review-person { display: flex; flex-direction: column; line-height: 1.35; }
.review-name { font-size: 14.5px; font-weight: 600; }
.review-date {
  font-size: 12px;
  color: var(--text-light);
  font-variant-numeric: tabular-nums;
}

.review-grid > .reveal:nth-child(2) { --reveal-delay: 70ms; }
.review-grid > .reveal:nth-child(3) { --reveal-delay: 70ms; }
.review-grid > .reveal:nth-child(4) { --reveal-delay: 140ms; }

/* ------------------------- FAQ ------------------------- */
.faq { background: var(--bg); }

.faq-wrap {
  display: grid;
  grid-template-columns: minmax(0, .82fr) minmax(0, 1.18fr);
  gap: clamp(28px, 5vw, 72px);
  align-items: start;
}
.faq-head {
  position: sticky;
  top: calc(var(--header-h) + 36px);
}

.faq-list { border-top: 1px solid var(--line-strong); }

.faq-item { border-bottom: 1px solid var(--line-strong); }

.faq-trigger {
  display: flex;
  align-items: center;
  gap: 16px;
  width: 100%;
  padding: 22px 4px;
  border: 0;
  background: none;
  text-align: left;
  cursor: pointer;
}
.faq-index {
  flex: 0 0 auto;
  width: 24px;
  font-size: 11px;
  font-weight: 600;
  letter-spacing: .08em;
  color: #a3abb2;
  font-variant-numeric: tabular-nums;
}
.faq-q {
  flex: 1 1 auto;
  font-size: 16px;
  font-weight: 600;
  letter-spacing: -.01em;
  color: var(--text);
  transition: color .25s var(--ease);
}
.faq-trigger:hover .faq-q { color: var(--brand); }

.faq-icon {
  position: relative;
  flex: 0 0 auto;
  width: 26px;
  height: 26px;
  border: 1px solid var(--line-strong);
  border-radius: 50%;
  transition: background .3s var(--ease), border-color .3s var(--ease), transform .45s var(--ease);
}
.faq-icon::before,
.faq-icon::after {
  content: "";
  position: absolute;
  top: 50%;
  left: 50%;
  background: var(--text-muted);
  border-radius: 1px;
  transition: background .3s var(--ease), transform .35s var(--ease), opacity .3s var(--ease);
}
.faq-icon::before {
  width: 10px;
  height: 1.5px;
  transform: translate(-50%, -50%);
}
.faq-icon::after {
  width: 1.5px;
  height: 10px;
  transform: translate(-50%, -50%);
}

.faq-item.is-open .faq-icon {
  background: var(--brand);
  border-color: var(--brand);
  transform: rotate(180deg);
}
.faq-item.is-open .faq-icon::before,
.faq-item.is-open .faq-icon::after { background: #fff; }
.faq-item.is-open .faq-icon::after { transform: translate(-50%, -50%) scaleY(0); }

.faq-panel {
  display: grid;
  grid-template-rows: 0fr;
  transition: grid-template-rows .45s var(--ease);
}
.faq-panel-inner {
  overflow: hidden;
  opacity: 0;
  transition: opacity .3s var(--ease);
}
.faq-item.is-open .faq-panel { grid-template-rows: 1fr; }
.faq-item.is-open .faq-panel-inner { opacity: 1; transition-delay: .1s; }

.faq-a {
  max-width: 62ch;
  padding: 0 4px 26px 40px;
  font-size: 14.5px;
  line-height: 1.85;
  color: var(--text-muted);
}

/* ------------------------- 下载（重点区） ------------------------- */
.download {
  position: relative;
  overflow: hidden;
  padding-block: clamp(68px, 8vw, 122px);
  background: var(--brand-dark);
  color: #fff;
  border-bottom: 0;
}
.download::before {
  content: "";
  position: absolute;
  inset: 0;
  pointer-events: none;
  background:
    radial-gradient(760px 460px at 86% -6%, rgba(255, 255, 255, .09), transparent 62%),
    radial-gradient(680px 520px at 6% 106%, rgba(154, 96, 71, .26), transparent 64%);
}
.download::after {
  content: "";
  position: absolute;
  left: 50%;
  bottom: -46%;
  width: min(880px, 78vw);
  height: 420px;
  transform: translateX(-50%);
  border: 1px solid rgba(255, 255, 255, .07);
  border-radius: 50%;
  pointer-events: none;
}

.download-inner { position: relative; }

.download-copy {
  max-width: 780px;
  margin-inline: auto;
  text-align: center;
}
.download-title {
  margin-top: 16px;
  font-size: clamp(2.1rem, 4.2vw, 3.35rem);
  font-weight: 600;
  line-height: 1.16;
  letter-spacing: -.03em;
  color: #fff;
}
.download-desc {
  margin: 18px auto 0;
  max-width: 52ch;
  font-size: 15.5px;
  line-height: 1.8;
  color: rgba(255, 255, 255, .68);
}

.store-row {
  display: flex;
  justify-content: center;
  flex-wrap: wrap;
  gap: 14px;
  margin-top: clamp(34px, 4vw, 52px);
}

.store-btn {
  display: flex;
  align-items: center;
  gap: 15px;
  min-width: 268px;
  padding: 18px 24px;
  border: 1px solid transparent;
  border-radius: var(--radius);
  text-align: left;
  transition: transform .32s var(--ease), background .32s var(--ease), color .32s var(--ease), border-color .32s var(--ease), box-shadow .32s var(--ease);
}
.store-btn:hover { transform: translateY(-3px); }
.store-btn:active { transform: translateY(1px) scale(.99); }

.store-btn--android {
  background: #fbfbfc;
  color: var(--brand-dark);
  box-shadow: 0 22px 40px -24px rgba(0, 0, 0, .8);
}
.store-btn--android:hover { background: #fff; box-shadow: 0 28px 48px -24px rgba(0, 0, 0, .85); }
.store-btn--android .store-label { color: #6f7880; }
.store-btn--android .store-arrow { color: var(--brand); }

.store-btn--ios {
  background: rgba(255, 255, 255, .05);
  border-color: rgba(255, 255, 255, .28);
  color: #fff;
}
.store-btn--ios:hover {
  background: rgba(255, 255, 255, .12);
  border-color: rgba(255, 255, 255, .45);
}
.store-btn--ios .store-label { color: rgba(255, 255, 255, .6); }
.store-btn--ios .store-arrow { color: rgba(255, 255, 255, .8); }

.store-icon { display: grid; place-items: center; flex: 0 0 auto; width: 28px; height: 28px; }
.store-icon svg { width: 26px; height: 26px; }
.store-btn--ios .store-icon svg { width: 24px; height: 24px; }

.store-copy { display: flex; flex-direction: column; line-height: 1.25; }
.store-label {
  font-size: 10.5px;
  font-weight: 600;
  letter-spacing: .14em;
  text-transform: uppercase;
}
.store-title { margin-top: 5px; font-size: 16.5px; font-weight: 600; letter-spacing: .01em; }

.store-arrow {
  display: grid;
  place-items: center;
  margin-left: auto;
  width: 30px;
  height: 30px;
  border-radius: 50%;
  background: rgba(255, 255, 255, .1);
  transition: transform .32s var(--ease);
}
.store-btn--android .store-arrow { background: rgba(61, 68, 75, .08); }
.store-btn:hover .store-arrow { transform: translateY(2px); }

.download-note {
  margin-top: 28px;
  font-size: 12.5px;
  letter-spacing: .02em;
  color: rgba(255, 255, 255, .5);
  font-variant-numeric: tabular-nums;
}

/* ------------------------- 页脚 ------------------------- */
.site-footer { background: var(--bg); padding-block: clamp(48px, 5vw, 72px) 30px; }

.footer-top {
  display: grid;
  grid-template-columns: minmax(0, 1.3fr) auto auto;
  align-items: center;
  gap: 28px 40px;
  padding-bottom: 38px;
  border-bottom: 1px solid var(--line);
}

.footer-brand { display: flex; flex-direction: column; gap: 14px; }
.footer-slogan { font-size: 13.5px; color: var(--text-muted); }

.footer-links {
  display: flex;
  flex-wrap: wrap;
  gap: 4px 22px;
  font-size: 13.5px;
  color: var(--text-muted);
}
.footer-links a { transition: color .25s var(--ease); }
.footer-links a:hover { color: var(--text); }

.footer-cta { padding: 9px 18px; font-size: 13.5px; }

.footer-bottom {
  display: flex;
  flex-wrap: wrap;
  justify-content: space-between;
  align-items: center;
  gap: 8px 24px;
  padding-top: 24px;
  font-size: 12px;
  color: var(--text-light);
}
.footer-note { max-width: 62ch; text-align: right; }

/* ------------------------- 响应式：平板 ------------------------- */
@media (max-width: 1199px) {
  :root { --header-h: 70px; }

  .hero-grid { gap: 36px; }
  .hero-title { font-size: clamp(2.6rem, 4.9vw, 3.6rem); }
  .shot-stage { width: clamp(230px, 24vw, 280px); }

  .feature-grid { gap: 16px; }
  .feature-card { padding: 24px; }
}

@media (max-width: 1023px) {
  .intro-grid { grid-template-columns: 1fr; gap: 26px; }
  .intro-lead .section-title { max-width: 30ch; }
  .stat-row { margin-top: 26px; }

  .feature-grid { grid-template-columns: repeat(2, minmax(0, 1fr)); }
  .feature-grid > .reveal:nth-child(3n + 2) { --reveal-delay: 0ms; }
  .feature-grid > .reveal:nth-child(3n + 3) { --reveal-delay: 0ms; }
  .feature-grid > .reveal:nth-child(even) { --reveal-delay: 70ms; }

  .faq-wrap { grid-template-columns: 1fr; gap: 28px; }
  .faq-head { position: static; }
  .faq-head .section-desc { margin-bottom: 4px; }
}

@media (max-width: 940px) {
  .hero-grid {
    grid-template-columns: 1fr;
    gap: 42px;
    justify-items: start;
  }
  .hero-copy { max-width: 620px; }
  .hero-visual {
    width: 100%;
    padding-top: 8px;
  }
  .shot-stage { width: clamp(244px, 44vw, 300px); }
  .hero-title { font-size: clamp(2.7rem, 6.4vw, 3.6rem); }
}

/* ------------------------- 响应式：导航折叠 ------------------------- */
@media (max-width: 899px) {
  .nav {
    position: absolute;
    top: 100%;
    left: 0;
    right: 0;
    display: block;
    margin: 0;
    padding: 8px 0 18px;
    background: rgba(252, 253, 253, .98);
    -webkit-backdrop-filter: blur(16px);
    backdrop-filter: blur(16px);
    border-bottom: 1px solid var(--line);
    box-shadow: 0 28px 46px -34px rgba(29, 33, 37, .55);
    opacity: 0;
    visibility: hidden;
    transform: translateY(-8px);
    transition: opacity .3s var(--ease), transform .3s var(--ease), visibility .3s;
    pointer-events: none;
  }
  .nav.is-open {
    opacity: 1;
    visibility: visible;
    transform: translateY(0);
    pointer-events: auto;
  }
  .nav a {
    display: flex;
    align-items: center;
    justify-content: space-between;
    padding: 14px 22px;
    border-radius: 0;
    border-bottom: 1px solid var(--line);
    font-size: 15.5px;
  }
  .nav a:last-child { border-bottom: 0; }
  .nav a:hover { background: rgba(61, 68, 75, .04); }

  .nav-toggle { display: grid; }
  .header-inner { gap: 16px; }
}

/* ------------------------- 响应式：手机 ------------------------- */
@media (max-width: 767px) {
  :root { --header-h: 64px; }

  .container { padding-inline: 20px; }

  .hero { padding-block: 26px 40px; }
  .hero-title { font-size: clamp(2.25rem, 9vw, 2.9rem); }
  .hero-title__sub { font-size: 1.12rem; margin-top: 12px; }
  .lede { margin-top: 18px; font-size: 15px; }
  .hero-tags { margin-top: 18px; }
  .hero-cta { margin-top: 24px; gap: 12px 18px; }
  .btn--lg { padding: 14px 24px; font-size: 15px; }
  .link-arrow { font-size: 13.5px; }

  .meta-cards { gap: 8px; margin-top: 22px; }
  .meta-card { padding: 10px 11px; border-radius: 10px; }
  .meta-label { font-size: 9.5px; letter-spacing: .1em; }
  .meta-value { font-size: 13px; margin-top: 4px; }

  .hero-visual { gap: 16px; }
  .shot-stage { width: min(70vw, 288px); }
  /* 移动端叠放同一位置，只显示当前一张，其余淡出下沉 */
  .shot.is-left,
  .shot.is-right {
    opacity: 0;
    transform: translate3d(0, 14px, 0) scale(.92);
    pointer-events: none;
  }
  .shot.is-active { transform: translate3d(0, 0, 0) scale(1); }
  .shot-hint { display: none; }

  .section { padding-block: 56px; }
  .section-title { font-size: clamp(1.6rem, 7vw, 2rem); }

  .intro-body p { font-size: 14.5px; }
  .stat-row { grid-template-columns: 1fr; gap: 16px; }
  .stat-value { font-size: 1.3rem; }
  .stat-label { margin-top: 4px; }

  .feature-grid { grid-template-columns: 1fr; }
  .feature-grid > .reveal:nth-child(even) { --reveal-delay: 0ms; }
  .feature-card { padding: 24px; }
  .feature-icon { margin-bottom: 18px; }

  .review-grid { grid-template-columns: 1fr; }
  .review-grid > .reveal:nth-child(n) { --reveal-delay: 0ms; }
  .review-quote { font-size: 15px; }

  .faq-trigger { gap: 12px; padding: 20px 2px; }
  .faq-index { width: 20px; }
  .faq-q { font-size: 15px; }
  .faq-a { padding: 0 2px 24px 32px; font-size: 13.5px; }

  .download { padding-block: 64px 68px; }
  .download-title { font-size: clamp(1.85rem, 8vw, 2.4rem); }
  .download-desc { font-size: 14.5px; }
  .store-row { flex-direction: column; align-items: stretch; gap: 12px; margin-top: 32px; }
  .store-btn { width: 100%; min-width: 0; padding: 16px 20px; }
  .store-title { font-size: 15.5px; }
  .download-note { font-size: 11.5px; line-height: 1.7; }

  .footer-top { grid-template-columns: 1fr; gap: 22px; padding-bottom: 26px; justify-items: start; }
  .footer-links { gap: 4px 18px; }
  .footer-bottom { flex-direction: column; align-items: flex-start; gap: 10px; }
  .footer-note { text-align: left; }

  .header-actions .btn--primary { padding: 9px 16px; font-size: 13.5px; }
}

@media (max-width: 380px) {
  .brand-text .brand-sub { display: none; }
  .hero-title { font-size: 2.15rem; }
  .meta-value { font-size: 12px; }
  .header-actions .btn--primary { padding: 8px 13px; font-size: 12.5px; }
  .nav-toggle { width: 38px; height: 38px; }
}

/* ------------------------- 动效降级 ------------------------- */
@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; translate: 0 0; }
  .shot.is-right,
  .shot.is-left { transform: translate3d(0, 10px, 0) scale(.95); }
}