/* ==========================================================================
   小森 · xiaosen.ai · ice-blue / silver-white hardware site
   原生 CSS，无依赖。文件顺序：令牌 → 基础 → 组件 → 区块 → 响应式
   ========================================================================== */

/* ==== 1. 设计令牌 ==== */
:root {
  /* 字体：中文 PingFang SC 优先 */
  --font-sans: "PingFang SC", "HarmonyOS Sans SC", "Hiragino Sans GB",
               "Source Han Sans SC", "Noto Sans SC", "Microsoft YaHei",
               -apple-system, BlinkMacSystemFont, "Segoe UI", system-ui, sans-serif;
  --font-mono: "SF Mono", "JetBrains Mono", "PingFang SC", ui-monospace, monospace;

  /* 深海军蓝 */
  --navy-900: #0e1b2e;
  --navy-800: #14243c;
  --navy-700: #1d3050;

  /* 正文灰蓝 */
  --ink-600: #3f526e;
  --ink-500: #5c6f8a;
  --ink-400: #8194ab;

  /* 天空蓝 */
  --blue-700: #1668d4;
  --blue-600: #1e86f5;
  --blue-500: #3fa2ff;
  --blue-400: #74bcff;
  --blue-200: #cbe4fb;
  --blue-100: #e2f0fd;
  --blue-50: #f0f7fe;

  /* 冰蓝银白 */
  --ice-50: #fbfdff;
  --ice-100: #f5f9fd;
  --ice-200: #eaf3fc;
  --ice-300: #ddeaf7;
  --white: #ffffff;

  /* 细线 */
  --line: rgba(20, 42, 74, 0.085);
  --line-2: rgba(20, 42, 74, 0.14);
  --line-blue: rgba(30, 134, 245, 0.18);

  /* 阴影：柔和、低对比 */
  --shadow-xs: 0 1px 2px rgba(16, 40, 74, 0.04);
  --shadow-sm: 0 4px 14px -6px rgba(16, 40, 74, 0.12);
  --shadow-md: 0 18px 40px -24px rgba(16, 40, 74, 0.26);
  --shadow-lg: 0 40px 80px -48px rgba(16, 40, 74, 0.34);
  --shadow-cta: 0 12px 26px -12px rgba(30, 134, 245, 0.6);

  /* 尺寸 */
  --content: 1200px;
  --gutter: 24px;
  --header-h: 72px;
  --radius-sm: 10px;
  --radius: 16px;
  --radius-lg: 24px;
  --radius-xl: 32px;

  --ease: cubic-bezier(0.22, 0.61, 0.36, 1);
}

/* ==== 2. 基础 ==== */
*, *::before, *::after { box-sizing: border-box; }

[hidden] { display: none !important; }

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

body {
  margin: 0;
  font-family: var(--font-sans);
  font-size: 16px;
  line-height: 1.7;
  color: var(--ink-600);
  background: var(--ice-50);
  -webkit-font-smoothing: antialiased;
  -moz-osx-font-smoothing: grayscale;
  text-rendering: optimizeLegibility;
  overflow-x: hidden;
}

/* 极轻的颗粒，给纯色背景一点摄影质感 */
body::before {
  content: "";
  position: fixed;
  inset: 0;
  z-index: 1;
  pointer-events: none;
  opacity: 0.028;
  background-image: url("data:image/svg+xml,%3Csvg xmlns='http://www.w3.org/2000/svg' width='160' height='160'%3E%3Cfilter id='n'%3E%3CfeTurbulence type='fractalNoise' baseFrequency='0.8' numOctaves='3' stitchTiles='stitch'/%3E%3C/filter%3E%3Crect width='160' height='160' filter='url(%23n)'/%3E%3C/svg%3E");
}

h1, h2, h3, h4 {
  margin: 0;
  color: var(--navy-900);
  font-weight: 600;
  line-height: 1.24;
  letter-spacing: -0.015em;
}

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

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

a { color: inherit; text-decoration: none; }

button {
  font: inherit;
  color: inherit;
  background: none;
  border: 0;
  padding: 0;
  cursor: pointer;
}

svg { display: block; }

::selection { background: var(--blue-200); color: var(--navy-900); }

:focus-visible {
  outline: 2px solid var(--blue-600);
  outline-offset: 3px;
  border-radius: 6px;
}

/* ==== 3. 工具类 ==== */
.container {
  width: 100%;
  max-width: calc(var(--content) + var(--gutter) * 2);
  margin-inline: auto;
  padding-inline: var(--gutter);
}

.sr-only {
  position: absolute;
  width: 1px; height: 1px;
  padding: 0; margin: -1px;
  overflow: hidden;
  clip: rect(0 0 0 0);
  clip-path: inset(50%);
  white-space: nowrap;
  border: 0;
}

.skip-link {
  position: fixed;
  top: 10px; left: 50%;
  transform: translate(-50%, -180%);
  z-index: 200;
  padding: 10px 20px;
  border-radius: 999px;
  background: var(--white);
  color: var(--navy-900);
  font-size: 14px;
  box-shadow: var(--shadow-md);
  transition: transform 0.22s var(--ease);
}
.skip-link:focus { transform: translate(-50%, 0); }

.eyebrow {
  display: flex;
  align-items: center;
  gap: 12px;
  margin: 0 0 22px;
  font-size: 11px;
  font-weight: 500;
  line-height: 1;
  letter-spacing: 0.2em;
  text-transform: uppercase;
  color: var(--ink-400);
}
.eyebrow--plain { display: block; }

.eyebrow__label { color: var(--ink-400); }

.chip {
  display: inline-flex;
  align-items: center;
  height: 24px;
  padding: 0 11px;
  border-radius: 999px;
  border: 1px solid var(--line-blue);
  background: rgba(255, 255, 255, 0.72);
  color: var(--blue-700);
  font-size: 11px;
  font-weight: 500;
  letter-spacing: 0.06em;
  text-transform: none;
}

.btn {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  gap: 8px;
  height: 46px;
  padding: 0 26px;
  border-radius: 999px;
  border: 1px solid transparent;
  font-size: 15px;
  font-weight: 500;
  letter-spacing: 0.01em;
  white-space: nowrap;
  cursor: pointer;
  transition: transform 0.2s var(--ease), box-shadow 0.24s var(--ease),
              background-color 0.2s var(--ease), border-color 0.2s var(--ease),
              color 0.2s var(--ease);
}
.btn--lg { height: 52px; padding: 0 32px; font-size: 16px; }
.btn--sm { height: 40px; padding: 0 20px; font-size: 14px; }

.btn--primary {
  background: linear-gradient(180deg, var(--blue-500), var(--blue-600));
  color: #fff;
  box-shadow: var(--shadow-cta);
}
.btn--primary:hover { transform: translateY(-1px); box-shadow: 0 18px 34px -14px rgba(30, 134, 245, 0.7); }
.btn--primary:active { transform: translateY(0); }

.btn--ghost {
  background: rgba(255, 255, 255, 0.66);
  border-color: var(--line-2);
  color: var(--navy-800);
  backdrop-filter: blur(10px);
  -webkit-backdrop-filter: blur(10px);
}
.btn--ghost:hover { background: #fff; border-color: var(--blue-200); color: var(--blue-700); }

.btn--outline {
  background: transparent;
  border-color: var(--line-2);
  color: var(--navy-800);
}
.btn--outline:hover { border-color: var(--blue-500); color: var(--blue-700); background: var(--blue-50); }

.btn--quiet {
  background: var(--ice-100);
  color: var(--ink-600);
}
.btn--quiet:hover { background: var(--ice-200); color: var(--navy-800); }

.linklike {
  font: inherit;
  color: inherit;
  cursor: pointer;
  border-bottom: 1px solid transparent;
  transition: color 0.2s var(--ease), border-color 0.2s var(--ease);
}
.linklike:hover { color: var(--blue-700); border-bottom-color: currentColor; }

/* 通用区块 */
.section {
  position: relative;
  padding-block: 132px;
}

/* sticky header 锚点偏移：跳转时标题不被导航遮住 */
section[id],
main[id] {
  scroll-margin-top: calc(var(--header-h) + 24px);
}
#top { scroll-margin-top: 0; }
.section--tint {
  background: linear-gradient(180deg, var(--ice-50) 0%, var(--ice-100) 34%, var(--ice-100) 66%, var(--ice-50) 100%);
  border-block: 1px solid var(--line);
}

.section__head { max-width: 660px; margin-bottom: 64px; }
.section__title { font-size: clamp(30px, 3.6vw, 46px); }
.section__lead {
  margin-top: 20px;
  font-size: 17px;
  line-height: 1.85;
  color: var(--ink-500);
}

.fineprint {
  margin-top: 40px;
  font-size: 13px;
  line-height: 1.8;
  color: var(--ink-400);
}

/* ==== 4. 导航 ==== */
.site-header {
  position: sticky;
  top: 0;
  z-index: 80;
  background: rgba(252, 253, 255, 0.72);
  backdrop-filter: saturate(180%) blur(18px);
  -webkit-backdrop-filter: saturate(180%) blur(18px);
  border-bottom: 1px solid transparent;
  transition: border-color 0.3s var(--ease), background-color 0.3s var(--ease);
}
.site-header.is-stuck {
  border-bottom-color: var(--line);
  background: rgba(252, 253, 255, 0.86);
}

.site-header__inner {
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 24px;
  height: var(--header-h);
}

.brand {
  display: inline-flex;
  align-items: center;
  gap: 9px;
  flex: none;
}
.brand__mark {
  display: grid;
  place-items: center;
  width: 32px; height: 32px;
  border-radius: 10px;
  background: linear-gradient(160deg, #fff, var(--blue-100));
  border: 1px solid var(--line-blue);
  color: var(--blue-600);
  box-shadow: var(--shadow-xs);
}
.brand__mark svg { width: 21px; height: 21px; }
.brand__name {
  font-size: 19px;
  font-weight: 600;
  letter-spacing: 0.06em;
  color: var(--navy-900);
}
.brand__ver {
  font-size: 11px;
  letter-spacing: 0.06em;
  color: var(--ink-400);
  padding-top: 2px;
}

.site-nav {
  display: flex;
  align-items: center;
  gap: 40px;
}
.site-nav__list {
  display: flex;
  align-items: center;
  gap: 34px;
}
.site-nav__link {
  position: relative;
  font-size: 14.5px;
  letter-spacing: 0.04em;
  color: var(--ink-600);
  padding-block: 6px;
  transition: color 0.2s var(--ease);
}
.site-nav__link::after {
  content: "";
  position: absolute;
  left: 0; right: 0; bottom: 0;
  height: 1px;
  background: var(--blue-600);
  transform: scaleX(0);
  transform-origin: left;
  transition: transform 0.26s var(--ease);
}
.site-nav__link:hover { color: var(--navy-900); }
.site-nav__link:hover::after,
.site-nav__link.is-current::after { transform: scaleX(1); }
.site-nav__link.is-current { color: var(--navy-900); }

.nav-toggle {
  display: none;
  width: 42px; height: 42px;
  border-radius: 12px;
  border: 1px solid var(--line);
  background: rgba(255, 255, 255, 0.7);
  place-items: center;
  flex: none;
}
.nav-toggle__bars {
  display: grid;
  gap: 4px;
  width: 18px;
}
.nav-toggle__bars i {
  display: block;
  height: 1.5px;
  border-radius: 2px;
  background: var(--navy-800);
  transition: transform 0.26s var(--ease), opacity 0.18s var(--ease);
}
.nav-toggle[aria-expanded="true"] .nav-toggle__bars i:nth-child(1) { transform: translateY(5.5px) 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(-5.5px) rotate(-45deg); }

/* ==== 5. 首屏 ==== */
.hero {
  position: relative;
  display: flex;
  align-items: center;
  min-height: 680px;
  padding-block: 96px 104px;
  overflow: hidden;
  isolation: isolate;
}

.hero__bg {
  position: absolute;
  inset: 0;
  z-index: -2;
  background:
    radial-gradient(120% 100% at 8% 0%, #ffffff 0%, rgba(255, 255, 255, 0) 56%),
    linear-gradient(180deg, #f7fbff 0%, #eef6fd 52%, #fbfdff 100%);
}
.hero__glow {
  position: absolute;
  border-radius: 50%;
  filter: blur(70px);
}
.hero__glow--a {
  width: 46vw; height: 46vw;
  max-width: 620px; max-height: 620px;
  right: 4%; top: -14%;
  background: radial-gradient(circle, rgba(116, 188, 255, 0.42), rgba(116, 188, 255, 0) 68%);
}
.hero__glow--b {
  width: 34vw; height: 34vw;
  max-width: 460px; max-height: 460px;
  left: -8%; bottom: -22%;
  background: radial-gradient(circle, rgba(203, 228, 251, 0.6), rgba(203, 228, 251, 0) 70%);
}
.hero__grid {
  position: absolute;
  inset: 0;
  opacity: 0.5;
  background-image:
    linear-gradient(to right, rgba(20, 42, 74, 0.045) 1px, transparent 1px),
    linear-gradient(to bottom, rgba(20, 42, 74, 0.045) 1px, transparent 1px);
  background-size: 96px 96px;
  -webkit-mask-image: radial-gradient(120% 90% at 72% 40%, #000 0%, transparent 72%);
  mask-image: radial-gradient(120% 90% at 72% 40%, #000 0%, transparent 72%);
}

.hero__media {
  position: absolute;
  inset: 0;
  z-index: -1;
  overflow: hidden;
}
.hero__img {
  width: 100%;
  height: 100%;
  object-fit: cover;
  object-position: 68% 44%;
}
/* 图片左侧渐隐，给文案留出干净底子 */
.hero__media::after {
  content: "";
  position: absolute;
  inset: 0;
  background: linear-gradient(
    90deg,
    #f8fcff 0%,
    rgba(248, 252, 255, 0.94) 24%,
    rgba(248, 252, 255, 0.55) 43%,
    rgba(248, 252, 255, 0) 64%
  );
}

.hero__inner { position: relative; z-index: 2; }

.hero__copy { max-width: 560px; }

.hero__title {
  font-size: clamp(42px, 4.5vw, 64px);
  line-height: 1.14;
  letter-spacing: -0.03em;
  color: var(--navy-900);
}
/* 两行标题：每一行都不折行，第二行完整显示 */
.hero__title-line {
  display: block;
  white-space: nowrap;
}
.hero__sub {
  margin-top: 24px;
  max-width: 420px;
  font-size: 18px;
  line-height: 1.8;
  color: var(--ink-500);
}
.hero__actions {
  display: flex;
  flex-wrap: wrap;
  gap: 14px;
  margin-top: 40px;
}
.hero__note {
  margin-top: 26px;
  font-size: 12.5px;
  letter-spacing: 0.04em;
  color: var(--ink-400);
}

/* 首屏文案入场（纯 CSS，无 JS 也生效） */
@keyframes hero-in {
  from { opacity: 0; transform: translateY(16px); }
  to { opacity: 1; transform: none; }
}
.hero__copy > * { animation: hero-in 0.85s var(--ease) both; }
.hero__copy > *:nth-child(1) { animation-delay: 0.06s; }
.hero__copy > *:nth-child(2) { animation-delay: 0.14s; }
.hero__copy > *:nth-child(3) { animation-delay: 0.22s; }
.hero__copy > *:nth-child(4) { animation-delay: 0.30s; }
.hero__copy > *:nth-child(5) { animation-delay: 0.38s; }

/* ==== 6. 六能力横条 ==== */
.abilities-band {
  position: relative;
  z-index: 0;
  background: var(--white);
  border-top: 1px solid var(--line);
  border-bottom: 1px solid var(--line);
}
.abilities {
  display: grid;
  grid-template-columns: repeat(6, minmax(0, 1fr));
  gap: 1px;
  background: var(--line);
}
.ability {
  display: flex;
  flex-direction: column;
  align-items: flex-start;
  gap: 4px;
  padding: 36px 22px 34px;
  background: var(--white);
  transition: background-color 0.3s var(--ease);
}
.ability:hover { background: var(--blue-50); }
.ability__icon {
  display: grid;
  place-items: center;
  width: 34px; height: 34px;
  margin-bottom: 16px;
  color: var(--blue-600);
  transition: transform 0.3s var(--ease);
}
.ability__icon svg { width: 24px; height: 24px; }
.ability:hover .ability__icon { transform: translateY(-2px); }
.ability__name {
  font-size: 15px;
  font-weight: 500;
  letter-spacing: 0.02em;
  color: var(--navy-900);
}
.ability__en {
  font-size: 10.5px;
  letter-spacing: 0.18em;
  text-transform: uppercase;
  color: var(--ink-400);
}

/* ==== 7. 为什么是小森 ==== */
.why {
  display: grid;
  grid-template-columns: minmax(0, 0.86fr) minmax(0, 1.14fr);
  gap: 72px;
  align-items: start;
}
.why__intro { position: sticky; top: calc(var(--header-h) + 48px); }
.why__points {
  display: grid;
  gap: 16px;
  margin-top: 36px;
  padding-top: 32px;
  border-top: 1px solid var(--line);
}
.why__points li {
  display: grid;
  grid-template-columns: 22px minmax(0, 1fr);
  gap: 12px;
  font-size: 14.5px;
  line-height: 1.75;
  color: var(--ink-500);
}
.why__points strong {
  display: block;
  color: var(--navy-900);
  font-weight: 500;
}
.why__check {
  display: grid;
  place-items: center;
  width: 22px; height: 22px;
  margin-top: 3px;
  border-radius: 50%;
  background: var(--blue-100);
  color: var(--blue-700);
}
.why__check svg { width: 13px; height: 13px; }

.why__grid {
  display: grid;
  grid-template-columns: repeat(2, minmax(0, 1fr));
  gap: 28px 24px;
}

.feature-card {
  display: flex;
  flex-direction: column;
}
.feature-card__media {
  position: relative;
  overflow: hidden;
  aspect-ratio: 4 / 3;
  border-radius: var(--radius-lg);
  border: 1px solid var(--line);
  background: linear-gradient(150deg, var(--ice-100), var(--ice-300));
  box-shadow: var(--shadow-sm);
}
.feature-card__media img {
  width: 100%; height: 100%;
  object-fit: cover;
  transform: scale(var(--zoom, 1));
  transform-origin: var(--fx, 50%) var(--fy, 50%);
  transition: transform 0.7s var(--ease);
}
.feature-card:hover .feature-card__media img {
  transform: scale(calc(var(--zoom, 1) * 1.045));
}
/* 图片下方的柔和内阴影，避免卡片显得像截图 */
.feature-card__media::after {
  content: "";
  position: absolute;
  inset: 0;
  box-shadow: inset 0 -40px 60px -40px rgba(16, 40, 74, 0.28);
  pointer-events: none;
}
.feature-card__title {
  margin-top: 22px;
  font-size: 19px;
  letter-spacing: -0.005em;
}
.feature-card__text {
  margin-top: 10px;
  font-size: 14.5px;
  line-height: 1.8;
  color: var(--ink-500);
}

/* ==== 8. 场景 / Tabs ==== */
.tabs__list {
  display: flex;
  flex-wrap: wrap;
  gap: 8px;
  padding: 7px;
  border-radius: 999px;
  border: 1px solid var(--line);
  background: rgba(255, 255, 255, 0.72);
  backdrop-filter: blur(10px);
  -webkit-backdrop-filter: blur(10px);
  width: fit-content;
  max-width: 100%;
  box-shadow: var(--shadow-xs);
}
.tab {
  height: 42px;
  padding: 0 22px;
  border-radius: 999px;
  font-size: 14.5px;
  letter-spacing: 0.02em;
  color: var(--ink-500);
  white-space: nowrap;
  transition: background-color 0.24s var(--ease), color 0.24s var(--ease), box-shadow 0.24s var(--ease);
}
.tab:hover { color: var(--navy-900); background: var(--ice-100); }
.tab[aria-selected="true"] {
  background: linear-gradient(180deg, var(--blue-500), var(--blue-600));
  color: #fff;
  box-shadow: var(--shadow-cta);
}

.tabs__panels { margin-top: 44px; }

.panel {
  display: grid;
  grid-template-columns: minmax(0, 1fr) minmax(0, 1.02fr);
  gap: 64px;
  align-items: start;
  animation: panel-in 0.42s var(--ease) both;
}
@keyframes panel-in {
  from { opacity: 0; transform: translateY(10px); }
  to { opacity: 1; transform: none; }
}
.panel:focus-visible { outline-offset: 10px; }

.panel__title { font-size: clamp(24px, 2.4vw, 32px); }
.panel__text {
  margin-top: 18px;
  font-size: 16px;
  line-height: 1.9;
  color: var(--ink-500);
}

.dialogue {
  display: grid;
  gap: 12px;
  margin-top: 30px;
}
.bubble {
  position: relative;
  max-width: 94%;
  padding: 14px 18px;
  border-radius: 16px;
  font-size: 14.5px;
  line-height: 1.75;
}
.bubble__who {
  display: block;
  margin-bottom: 5px;
  font-size: 10.5px;
  letter-spacing: 0.16em;
  text-transform: uppercase;
}
.bubble--user {
  justify-self: end;
  background: var(--white);
  border: 1px solid var(--line);
  border-bottom-right-radius: 5px;
  color: var(--navy-800);
  box-shadow: var(--shadow-xs);
}
.bubble--user .bubble__who { color: var(--ink-400); }
.bubble--bot {
  background: linear-gradient(150deg, var(--blue-600), var(--blue-500));
  border-bottom-left-radius: 5px;
  color: #fff;
  box-shadow: var(--shadow-cta);
}
.bubble--bot .bubble__who { color: rgba(255, 255, 255, 0.72); }

.tags {
  display: flex;
  flex-wrap: wrap;
  gap: 8px;
  margin-top: 26px;
}
.tags li {
  padding: 6px 13px;
  border-radius: 999px;
  border: 1px solid var(--line-blue);
  background: rgba(255, 255, 255, 0.7);
  font-size: 12.5px;
  color: var(--blue-700);
}

/* 工作流 UI 模型 */
.workflow {
  border-radius: var(--radius-lg);
  border: 1px solid var(--line);
  background: var(--white);
  box-shadow: var(--shadow-md);
  overflow: hidden;
}
.workflow__bar {
  display: grid;
  grid-template-columns: auto minmax(0, 1fr) auto;
  align-items: center;
  gap: 14px;
  padding: 15px 20px;
  border-bottom: 1px solid var(--line);
  background: linear-gradient(180deg, #fff, var(--ice-100));
}
.workflow__dots { display: flex; gap: 6px; }
.workflow__dots i {
  width: 9px; height: 9px;
  border-radius: 50%;
  background: var(--ice-300);
}
.workflow__dots i:first-child { background: #cddff2; }
.workflow__title {
  font-size: 13px;
  font-weight: 500;
  letter-spacing: 0.02em;
  color: var(--navy-800);
}
.workflow__meta {
  font-family: var(--font-mono);
  font-size: 11.5px;
  letter-spacing: 0.06em;
  color: var(--ink-400);
}

.workflow__steps {
  display: grid;
  gap: 2px;
  padding: 18px 20px 20px;
}
.step {
  position: relative;
  display: grid;
  grid-template-columns: 22px minmax(0, 1fr) auto;
  align-items: center;
  gap: 14px;
  padding: 11px 0;
}
/* 竖向连接线 */
.step:not(:last-child)::before {
  content: "";
  position: absolute;
  left: 10.5px;
  top: 32px;
  bottom: -3px;
  width: 1px;
  background: var(--line-2);
}
.step:not(:last-child).is-done::before { background: var(--blue-200); }

/* 步骤标记（由 ::after 生成，无需额外标签） */
.step::after {
  content: "";
  grid-column: 1;
  grid-row: 1;
  width: 22px; height: 22px;
  border-radius: 50%;
  border: 1px solid var(--line-2);
  background: var(--white);
  background-position: center;
  background-repeat: no-repeat;
  display: block;
}
.step.is-done::after {
  border-color: var(--blue-600);
  background: var(--blue-600);
  background-image: url("data:image/svg+xml,%3Csvg xmlns='http://www.w3.org/2000/svg' viewBox='0 0 24 24' fill='none' stroke='%23ffffff' stroke-width='3.2' stroke-linecap='round' stroke-linejoin='round'%3E%3Cpath d='m5 12.6 4.4 4.4L19 7'/%3E%3C/svg%3E");
  background-size: 11px 11px;
  background-position: center;
  background-repeat: no-repeat;
}
.step.is-active::after {
  border-color: var(--blue-500);
  background: var(--white);
  box-shadow: 0 0 0 4px rgba(63, 162, 255, 0.16);
}
.step.is-active::before { background: var(--blue-200); }

.step__label {
  grid-column: 2;
  font-size: 14px;
  color: var(--ink-500);
}
.step.is-done .step__label { color: var(--ink-600); }
.step.is-active .step__label { color: var(--navy-900); font-weight: 500; }

.step__status {
  grid-column: 3;
  padding: 3px 10px;
  border-radius: 999px;
  font-size: 11px;
  letter-spacing: 0.04em;
  background: var(--ice-100);
  color: var(--ink-400);
  white-space: nowrap;
}
.step.is-done .step__status { background: var(--blue-50); color: var(--blue-700); }
.step.is-active .step__status { background: var(--blue-100); color: var(--blue-700); }

.workflow__foot {
  display: flex;
  align-items: center;
  gap: 14px;
  padding: 0 20px 20px;
}
.workflow__progress {
  flex: 1;
  height: 3px;
  border-radius: 999px;
  background: var(--ice-200);
  overflow: hidden;
}
.workflow__progress i {
  display: block;
  height: 100%;
  width: var(--p, 50%);
  border-radius: 999px;
  background: linear-gradient(90deg, var(--blue-400), var(--blue-600));
}
.workflow__caption {
  font-size: 11px;
  letter-spacing: 0.1em;
  text-transform: uppercase;
  color: var(--ink-400);
}

/* ==== 9. 隐私 ==== */
.privacy-grid {
  display: grid;
  grid-template-columns: repeat(4, minmax(0, 1fr));
  gap: 20px;
}
.privacy-card {
  padding: 32px 26px 34px;
  border-radius: var(--radius-lg);
  border: 1px solid var(--line);
  background: linear-gradient(170deg, #fff 0%, var(--ice-100) 100%);
  box-shadow: var(--shadow-xs);
  transition: transform 0.3s var(--ease), box-shadow 0.3s var(--ease), border-color 0.3s var(--ease);
}
.privacy-card:hover {
  transform: translateY(-3px);
  border-color: var(--line-blue);
  box-shadow: var(--shadow-sm);
}
.privacy-card__icon {
  display: grid;
  place-items: center;
  width: 42px; height: 42px;
  margin-bottom: 22px;
  border-radius: 13px;
  border: 1px solid var(--line-blue);
  background: rgba(255, 255, 255, 0.9);
  color: var(--blue-600);
}
.privacy-card__icon svg { width: 22px; height: 22px; }
.privacy-card__title { font-size: 17px; }
.privacy-card__text {
  margin-top: 12px;
  font-size: 14px;
  line-height: 1.85;
  color: var(--ink-500);
}

.privacy__actions {
  display: flex;
  flex-wrap: wrap;
  align-items: center;
  gap: 20px 28px;
  margin-top: 44px;
  padding-top: 36px;
  border-top: 1px solid var(--line);
}
.privacy__hint {
  display: flex;
  align-items: center;
  gap: 10px;
  font-size: 13.5px;
  color: var(--ink-400);
}
.privacy__hint-icon { color: var(--blue-500); }
.privacy__hint-icon svg { width: 18px; height: 18px; }

/* ==== 10. 底部 banner ==== */
.cta-banner {
  position: relative;
  overflow: hidden;
  padding-block: 128px;
  text-align: center;
  background: linear-gradient(180deg, var(--ice-50), var(--ice-200));
  border-top: 1px solid var(--line);
}
.cta-banner__bg { position: absolute; inset: 0; }
.cta-banner__glow {
  position: absolute;
  left: 50%; top: 8%;
  width: 780px; height: 780px;
  max-width: 120vw;
  transform: translateX(-50%);
  border-radius: 50%;
  filter: blur(80px);
  background: radial-gradient(circle, rgba(116, 188, 255, 0.4), rgba(116, 188, 255, 0) 66%);
}
.cta-banner__rings {
  position: absolute;
  left: 50%; top: 50%;
  width: 900px; height: 900px;
  transform: translate(-50%, -50%);
  border-radius: 50%;
  border: 1px solid var(--line-blue);
  box-shadow:
    0 0 0 120px rgba(255, 255, 255, 0.28),
    0 0 0 260px rgba(255, 255, 255, 0.18);
  opacity: 0.75;
}
.cta-banner__inner { position: relative; z-index: 1; }
.cta-banner__title {
  font-size: clamp(32px, 4.4vw, 56px);
  letter-spacing: -0.025em;
}
.cta-banner__text {
  margin: 22px auto 0;
  max-width: 460px;
  font-size: 17px;
  line-height: 1.85;
  color: var(--ink-500);
}
.cta-banner .btn { margin-top: 38px; }

/* ==== 11. 页脚 ==== */
.site-footer {
  padding-block: 56px 64px;
  background: var(--white);
  border-top: 1px solid var(--line);
}
.site-footer__inner {
  display: flex;
  flex-wrap: wrap;
  align-items: center;
  justify-content: space-between;
  gap: 24px 40px;
}
.site-footer__brand {
  display: inline-flex;
  align-items: center;
  gap: 9px;
}
.brand__mark--sm { width: 28px; height: 28px; border-radius: 9px; }
.brand__mark--sm svg { width: 18px; height: 18px; }
.site-footer__name {
  font-size: 16px;
  font-weight: 600;
  letter-spacing: 0.06em;
  color: var(--navy-900);
}
.site-footer__ver { font-size: 11px; color: var(--ink-400); }
.site-footer__nav {
  display: flex;
  flex-wrap: wrap;
  gap: 26px;
  font-size: 14px;
  color: var(--ink-500);
}
.site-footer__nav a:hover,
.site-footer__nav .linklike:hover { color: var(--blue-700); }
.site-footer__legal {
  flex: 1 0 100%;
  padding-top: 28px;
  border-top: 1px solid var(--line);
  font-size: 12.5px;
  letter-spacing: 0.04em;
  color: var(--ink-400);
}

/* ==== 12. 弹窗 ==== */
.modal {
  position: fixed;
  inset: 0;
  z-index: 120;
  display: grid;
  place-items: center;
  padding: 24px;
}
.modal__scrim {
  position: absolute;
  inset: 0;
  background: rgba(14, 27, 46, 0.34);
  backdrop-filter: blur(6px);
  -webkit-backdrop-filter: blur(6px);
  opacity: 0;
  transition: opacity 0.28s var(--ease);
}
.modal__panel {
  position: relative;
  display: flex;
  flex-direction: column;
  width: min(680px, 100%);
  max-height: min(86vh, 780px);
  border-radius: var(--radius-xl);
  border: 1px solid var(--line);
  background: var(--ice-50);
  box-shadow: var(--shadow-lg);
  overflow: hidden;
  opacity: 0;
  transform: translateY(14px) scale(0.985);
  transition: opacity 0.3s var(--ease), transform 0.34s var(--ease);
}
.modal__panel--doc { width: min(720px, 100%); }

.modal.is-open .modal__scrim { opacity: 1; }
.modal.is-open .modal__panel { opacity: 1; transform: none; }

.modal__head {
  display: flex;
  align-items: flex-start;
  justify-content: space-between;
  gap: 20px;
  padding: 28px 30px 0;
}
.modal__headings .eyebrow { margin-bottom: 12px; }
.modal__title { font-size: 26px; letter-spacing: -0.02em; }
.modal__close {
  display: grid;
  place-items: center;
  width: 38px; height: 38px;
  flex: none;
  border-radius: 50%;
  border: 1px solid var(--line);
  background: var(--white);
  color: var(--ink-500);
  transition: background-color 0.2s var(--ease), color 0.2s var(--ease), border-color 0.2s var(--ease);
}
.modal__close svg { width: 17px; height: 17px; }
.modal__close:hover { color: var(--navy-900); border-color: var(--line-2); }

.modal__note {
  display: flex;
  align-items: flex-start;
  gap: 10px;
  margin: 20px 30px 0;
  padding: 13px 16px;
  border-radius: var(--radius-sm);
  border: 1px solid var(--line-blue);
  background: var(--blue-50);
  font-size: 13px;
  line-height: 1.75;
  color: var(--blue-700);
}
.modal__note-icon { flex: none; margin-top: 2px; }
.modal__note-icon svg { width: 16px; height: 16px; }

.modal__body {
  padding: 26px 30px 4px;
  overflow-y: auto;
  -webkit-overflow-scrolling: touch;
}
.doc-block + .doc-block { margin-top: 28px; }
.doc-block h3 {
  font-size: 15px;
  letter-spacing: 0.02em;
  color: var(--navy-900);
}
.doc-list {
  display: grid;
  gap: 10px;
  margin-top: 14px;
}
.doc-list li {
  position: relative;
  padding-left: 20px;
  font-size: 14px;
  line-height: 1.85;
  color: var(--ink-500);
}
.doc-list li::before {
  content: "";
  position: absolute;
  left: 3px; top: 11px;
  width: 5px; height: 5px;
  border-radius: 50%;
  background: var(--blue-400);
}
.doc-list strong { color: var(--navy-800); font-weight: 500; }
.doc-block--muted {
  padding: 18px 20px;
  border-radius: var(--radius);
  background: var(--ice-100);
  border: 1px solid var(--line);
}
.doc-block--muted p {
  margin-top: 10px;
  font-size: 13.5px;
  line-height: 1.85;
  color: var(--ink-500);
}

.modal__foot {
  display: flex;
  flex-wrap: wrap;
  align-items: center;
  justify-content: flex-end;
  gap: 12px;
  padding: 20px 30px 26px;
  margin-top: auto;
}

/* ==== 13. 演示弹窗 ==== */
.demo {
  flex: 1;
  min-height: 0;
  display: flex;
  flex-direction: column;
  padding: 24px 30px 0;
  overflow-y: auto;
  -webkit-overflow-scrolling: touch;
}
.demo__prompt {
  margin-bottom: 16px;
  font-size: 14px;
  color: var(--ink-500);
}
.demo__options {
  display: grid;
  grid-template-columns: repeat(3, minmax(0, 1fr));
  gap: 12px;
}
.choice {
  display: flex;
  flex-direction: column;
  align-items: flex-start;
  gap: 8px;
  padding: 18px 16px;
  text-align: left;
  border-radius: var(--radius);
  border: 1px solid var(--line);
  background: var(--white);
  transition: transform 0.24s var(--ease), border-color 0.24s var(--ease), box-shadow 0.24s var(--ease);
}
.choice:hover:not(:disabled) {
  transform: translateY(-2px);
  border-color: var(--blue-200);
  box-shadow: var(--shadow-sm);
}
.choice:disabled { opacity: 0.45; cursor: not-allowed; }
.choice.is-picked {
  border-color: var(--blue-500);
  background: var(--blue-50);
}
.choice__icon { color: var(--blue-600); }
.choice__icon svg { width: 22px; height: 22px; }
.choice__label {
  font-size: 14.5px;
  font-weight: 500;
  color: var(--navy-900);
}
.choice__desc {
  font-size: 12px;
  line-height: 1.6;
  color: var(--ink-400);
}

.demo__thread {
  display: grid;
  gap: 14px;
  padding-bottom: 8px;
}
.msg {
  display: flex;
  gap: 10px;
  max-width: 84%;
  animation: msg-in 0.36s var(--ease) both;
}
@keyframes msg-in {
  from { opacity: 0; transform: translateY(8px); }
  to { opacity: 1; transform: none; }
}
.msg--user {
  justify-self: end;
  flex-direction: row-reverse;
}
.msg__avatar {
  display: grid;
  place-items: center;
  width: 30px; height: 30px;
  flex: none;
  border-radius: 10px;
  background: linear-gradient(160deg, var(--blue-500), var(--blue-600));
  color: #fff;
  font-size: 12px;
  font-weight: 600;
}
.msg__bubble {
  padding: 12px 16px;
  border-radius: 16px;
  font-size: 14.5px;
  line-height: 1.75;
}
.msg--bot .msg__bubble {
  background: var(--white);
  border: 1px solid var(--line);
  border-top-left-radius: 5px;
  color: var(--navy-800);
  box-shadow: var(--shadow-xs);
}
.msg--user .msg__bubble {
  background: linear-gradient(150deg, var(--blue-600), var(--blue-500));
  border-top-right-radius: 5px;
  color: #fff;
}
.msg--user .msg__avatar {
  background: var(--ice-200);
  color: var(--ink-500);
}

.dots { display: inline-flex; gap: 4px; align-items: center; height: 20px; }
.dots i {
  width: 5px; height: 5px;
  border-radius: 50%;
  background: var(--blue-400);
  animation: dot 1.1s var(--ease) infinite;
}
.dots i:nth-child(2) { animation-delay: 0.16s; }
.dots i:nth-child(3) { animation-delay: 0.32s; }
@keyframes dot {
  0%, 60%, 100% { opacity: 0.3; transform: translateY(0); }
  30% { opacity: 1; transform: translateY(-3px); }
}

.demo__done {
  display: flex;
  align-items: center;
  gap: 10px;
  padding: 12px 16px;
  border-radius: var(--radius-sm);
  background: var(--ice-100);
  border: 1px dashed var(--line-2);
  font-size: 12.5px;
  line-height: 1.7;
  color: var(--ink-400);
}

/* ==== 14. 滚动揭示 ==== */
[data-reveal] {
  opacity: 0;
  transform: translateY(18px);
  transition: opacity 0.7s var(--ease), transform 0.7s var(--ease);
}
[data-reveal].is-visible { opacity: 1; transform: none; }
/* 无 JS 时的兜底：内容始终可见 */
.no-js [data-reveal] { opacity: 1; transform: none; }

/* ==== 15. 响应式 ==== */
@media (max-width: 1180px) {
  .why { gap: 52px; }
  /* 中窄屏：图片右移并加强左侧留白，避免文案压在机身上 */
  .hero__img { object-position: 76% 44%; }
  .hero__media::after {
    background: linear-gradient(
      90deg,
      #f8fcff 0%,
      rgba(248, 252, 255, 0.97) 32%,
      rgba(248, 252, 255, 0.72) 52%,
      rgba(248, 252, 255, 0) 74%
    );
  }
}

@media (max-width: 1080px) {
  .section { padding-block: 104px; }
  .abilities { grid-template-columns: repeat(3, minmax(0, 1fr)); }
  .privacy-grid { grid-template-columns: repeat(2, minmax(0, 1fr)); }
  .panel { gap: 44px; }
}

@media (max-width: 980px) {
  .why {
    grid-template-columns: minmax(0, 1fr);
    gap: 48px;
  }
  .why__intro { position: static; }
  .panel {
    grid-template-columns: minmax(0, 1fr);
    gap: 36px;
  }
}

/* ==== 首屏切换为竖向排布：图片不再压在文案下面 ==== */
@media (max-width: 900px) {
  .hero {
    display: block;
    min-height: 0;
    padding-block: 64px 0;
  }
  .hero__media {
    position: relative;
    inset: auto;
    z-index: 0;
    margin-top: 44px;
    overflow: hidden;
    border-top: 1px solid var(--line);
    background: linear-gradient(160deg, var(--ice-100), var(--ice-300));
  }
  .hero__media::after {
    background: linear-gradient(180deg, rgba(248, 252, 255, 0.85) 0%, rgba(248, 252, 255, 0) 34%);
  }
  .hero__img {
    height: auto;
    aspect-ratio: 16 / 11;
    object-position: 62% 46%;
  }
  .hero__copy { max-width: 100%; }
  .hero__sub { max-width: 100%; }
  .hero__glow--a { top: 4%; right: -20%; opacity: 0.7; }
}

@media (max-width: 860px) {
  .site-header__inner {
    height: calc(var(--header-h) + env(safe-area-inset-top, 0px));
    padding-top: env(safe-area-inset-top, 0px);
  }
  .site-nav {
    position: absolute;
    top: calc(var(--header-h) + env(safe-area-inset-top, 0px) + 6px);
    left: var(--gutter);
    right: var(--gutter);
    display: grid;
    gap: 6px;
    max-height: calc(100vh - var(--header-h) - env(safe-area-inset-top, 0px) - 18px);
    max-height: calc(100dvh - var(--header-h) - env(safe-area-inset-top, 0px) - 18px);
    overflow-y: auto;
    -webkit-overflow-scrolling: touch;
    padding: 12px;
    padding-bottom: calc(12px + env(safe-area-inset-bottom, 0px));
    border-radius: var(--radius-lg);
    border: 1px solid var(--line);
    background: rgba(255, 255, 255, 0.96);
    backdrop-filter: blur(18px);
    -webkit-backdrop-filter: blur(18px);
    box-shadow: var(--shadow-md);
    opacity: 0;
    visibility: hidden;
    transform: translateY(-8px);
    transition: opacity 0.26s var(--ease), transform 0.26s var(--ease), visibility 0.26s;
  }
  .site-nav.is-open {
    opacity: 1;
    visibility: visible;
    transform: none;
  }
  .site-nav__list {
    display: grid;
    gap: 2px;
  }
  .site-nav__link {
    display: flex;
    align-items: center;
    min-height: 44px;
    padding: 11px 14px;
    border-radius: 12px;
    font-size: 15.5px;
  }
  .site-nav__link:hover { background: var(--ice-100); }
  .site-nav__link::after { display: none; }
  .site-nav__cta {
    width: 100%;
    height: 46px;
    min-height: 44px;
    margin-top: 6px;
  }
  .nav-toggle { display: grid; width: 44px; height: 44px; }
}

@media (max-width: 720px) {
  :root { --gutter: 20px; --header-h: 64px; }
  .section { padding-block: 60px; }
  .section__head { margin-bottom: 32px; }
  .section__title { font-size: clamp(24px, 7vw, 30px); }
  .section__lead { font-size: 15.5px; line-height: 1.75; margin-top: 14px; }

  /* 首屏：紧凑排布，CTA 并列，主图裁掉左侧空白 */
  .hero { padding-block: 36px 0; }
  .hero__copy .eyebrow { margin-bottom: 12px; }
  .hero__title { font-size: clamp(34px, 10.4vw, 42px); line-height: 1.12; }
  .hero__sub { margin-top: 12px; font-size: 15px; line-height: 1.65; }
  .hero__actions { flex-wrap: nowrap; gap: 10px; margin-top: 22px; }
  .hero__actions .btn {
    flex: 1 1 0;
    min-width: 0;
    height: 48px;
    min-height: 44px;
    padding: 0 14px;
    font-size: 15px;
  }
  .hero__note { margin-top: 14px; font-size: 12px; }
  .hero__media {
    margin-top: 24px;
    width: 100%;
    height: clamp(280px, 82vw, 360px);
    aspect-ratio: auto;
    max-height: none;
  }
  .hero__img {
    width: 100%;
    height: 100%;
    aspect-ratio: auto;
    object-fit: cover;
    object-position: 90% 50%;
  }
  .hero__media::after {
    background: linear-gradient(180deg, rgba(248, 252, 255, 0.6) 0%, rgba(248, 252, 255, 0) 15%);
  }

  /* 六能力：紧凑 3 列 2 行，图标与标签居中 */
  .abilities { grid-template-columns: repeat(3, minmax(0, 1fr)); }
  .ability {
    align-items: center;
    text-align: center;
    gap: 2px;
    padding: 18px 10px 16px;
  }
  .ability__icon { margin-bottom: 8px; }
  .ability__name { font-size: 13px; line-height: 1.4; }
  .ability__en { font-size: 10px; letter-spacing: 0.12em; }

  /* 为什么：四卡改单列横向图文，图片高度受控 */
  .why { gap: 30px; }
  .why__points { margin-top: 22px; padding-top: 20px; gap: 12px; font-size: 14px; }
  .why__grid { grid-template-columns: minmax(0, 1fr); gap: 12px; }
  .feature-card {
    display: grid;
    grid-template-columns: clamp(88px, 27vw, 116px) minmax(0, 1fr);
    grid-template-rows: auto auto;
    column-gap: 14px;
    row-gap: 4px;
    padding: 12px;
    border: 1px solid var(--line);
    border-radius: var(--radius);
    background: var(--white);
    box-shadow: var(--shadow-xs);
  }
  .feature-card__media {
    grid-column: 1;
    grid-row: 1 / span 2;
    align-self: center;
    width: 100%;
    aspect-ratio: 1 / 1;
    border-radius: 14px;
  }
  .feature-card__title {
    grid-column: 2;
    grid-row: 1;
    align-self: end;
    margin-top: 0;
    font-size: 16px;
  }
  .feature-card__text {
    grid-column: 2;
    grid-row: 2;
    align-self: start;
    margin-top: 0;
    font-size: 13.5px;
    line-height: 1.65;
  }

  /* 场景：标签改多行网格，五项全部可见可点 */
  .tabs__list {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(132px, 1fr));
    gap: 8px;
    width: 100%;
    padding: 8px;
    border-radius: var(--radius);
    overflow: visible;
  }
  .tab { width: 100%; height: auto; min-height: 44px; padding: 10px 12px; font-size: 14px; }
  .tabs__panels { margin-top: 26px; }
  .panel { gap: 28px; }
  .panel__text { margin-top: 14px; font-size: 15px; line-height: 1.8; }
  .dialogue { margin-top: 20px; gap: 10px; }
  .bubble { max-width: 100%; padding: 12px 14px; font-size: 14px; }
  .tags { margin-top: 18px; }

  /* 工作流压紧，内容保留 */
  .workflow__bar { padding: 12px 14px; gap: 10px; }
  .workflow__title { font-size: 12.5px; }
  .workflow__steps { padding: 12px 14px 14px; }
  .step { grid-template-columns: 22px minmax(0, 1fr); row-gap: 3px; padding: 8px 0; gap: 10px; }
  .step__label { font-size: 13px; }
  .step__status { grid-column: 2; grid-row: 2; justify-self: start; }
  .workflow__foot { padding: 0 14px 14px; }

  /* 隐私：紧凑双列，操作区纵排防溢出 */
  .privacy-grid { grid-template-columns: repeat(2, minmax(0, 1fr)); gap: 12px; }
  .privacy-card { padding: 18px 16px; border-radius: var(--radius); }
  .privacy-card__icon { width: 36px; height: 36px; margin-bottom: 14px; border-radius: 11px; }
  .privacy-card__icon svg { width: 19px; height: 19px; }
  .privacy-card__title { font-size: 15.5px; }
  .privacy-card__text { margin-top: 8px; font-size: 13px; line-height: 1.7; }
  .privacy__actions {
    flex-direction: column;
    align-items: stretch;
    gap: 16px;
    margin-top: 28px;
    padding-top: 24px;
  }
  .privacy__actions > .btn { width: 100%; min-height: 44px; }
  .privacy__hint { font-size: 13px; }

  /* 底部 banner 与页脚防溢出 */
  .cta-banner { padding-block: 64px; }
  .cta-banner__title { font-size: clamp(26px, 7.6vw, 34px); }
  .cta-banner__text { margin-top: 16px; font-size: 15px; }
  .cta-banner .btn { margin-top: 24px; width: min(100%, 320px); min-height: 48px; }
  .cta-banner__rings { width: 520px; height: 520px; }
  .site-footer {
    padding-block: 36px 40px;
    padding-bottom: calc(40px + env(safe-area-inset-bottom, 0px));
  }
  .site-footer__inner { flex-direction: column; align-items: flex-start; gap: 16px; }
  .site-footer__nav { gap: 8px 18px; }
  .site-footer__nav a,
  .site-footer__nav .linklike { display: inline-flex; align-items: center; min-height: 44px; }
  .site-footer__legal { padding-top: 18px; font-size: 12px; }

  /* 弹窗变为底部抽屉式，适配动态视口与安全区 */
  .modal { padding: 0; place-items: end center; }
  .modal__panel {
    width: 100%;
    max-height: 92vh;
    max-height: 92dvh;
    border-radius: var(--radius-xl) var(--radius-xl) 0 0;
    transform: translateY(24px);
  }
  .modal__head,
  .modal__note,
  .modal__foot { flex: none; }
  .modal__head { padding: 22px 20px 0; }
  .modal__close { min-width: 44px; min-height: 44px; }
  .modal__note { margin: 16px 20px 0; }
  .modal__body { flex: 1 1 auto; min-height: 0; padding: 22px 20px 4px; }
  .demo { padding: 20px 20px 0; }
  .modal__foot { padding: 16px 20px calc(22px + env(safe-area-inset-bottom, 0px)); }
  .modal__foot .btn { flex: 1 1 auto; min-height: 44px; }
  .demo__options { grid-template-columns: minmax(0, 1fr); }
  .choice { flex-direction: row; align-items: center; gap: 12px; padding: 14px 16px; min-height: 44px; }
  .choice__desc { margin-left: auto; text-align: right; }
  .msg { max-width: 92%; }
}

@media (max-width: 420px) {
  :root { --gutter: 16px; }
  .section { padding-block: 56px; }
  .hero { padding-block: 32px 0; }
  .hero__title { font-size: clamp(34px, 10.4vw, 40px); }
  .hero__sub { font-size: 14.5px; margin-top: 10px; }
  .hero__actions { margin-top: 18px; }
  .hero__actions .btn { flex: 1 1 calc(50% - 5px); padding: 0 10px; font-size: 14.5px; }
  .hero__media { margin-top: 20px; }
  .eyebrow { flex-wrap: wrap; gap: 10px; }
  .choice__desc { display: none; }
  .site-footer__nav { gap: 6px 16px; }
}

/* 320 级窄屏：能力与隐私卡回到更宽松的列数 */
@media (max-width: 360px) {
  .abilities { grid-template-columns: repeat(2, minmax(0, 1fr)); }
  .privacy-grid { grid-template-columns: minmax(0, 1fr); }
}

/* ==== 16. 动效偏好 ==== */
@media (prefers-reduced-motion: reduce) {
  html { scroll-behavior: auto; }
  *, *::before, *::after {
    animation-duration: 0.001ms !important;
    animation-iteration-count: 1 !important;
    transition-duration: 0.001ms !important;
    scroll-behavior: auto !important;
  }
  [data-reveal] { opacity: 1; transform: none; }
  .dots i { opacity: 0.7; }
  .feature-card:hover .feature-card__media img { transform: none; }
  .btn--primary:hover { transform: none; }
}

/* ==== 17. 打印 / 高对比兜底 ==== */
@media (prefers-contrast: more) {
  :root {
    --line: rgba(20, 42, 74, 0.26);
    --line-2: rgba(20, 42, 74, 0.4);
    --ink-500: #3c4d66;
    --ink-400: #55677f;
  }
}