/* site.css —— 官网基础层 + 组件层
 * 依赖 tokens.css。顺序：基础 → 版心/导航 → 按钮 → 首屏 → 通用区块 → 卡片/网格
 *            → 手机示意 → 下载页 → 折叠问答 → 客服 → 法务文档 → 页脚 → 响应式
 */

/* ==================== 1. 基础 ==================== */
* { box-sizing: border-box; }

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

body {
  margin: 0;
  background: var(--bg);
  color: var(--text);
  font-family: -apple-system, BlinkMacSystemFont, "PingFang SC", "Hiragino Sans GB",
    "Microsoft YaHei", "Helvetica Neue", Helvetica, Arial, sans-serif;
  font-size: var(--fs-md);
  line-height: 1.6;
  -webkit-font-smoothing: antialiased;
  -moz-osx-font-smoothing: grayscale;
}

img { max-width: 100%; display: block; }
a { color: var(--brand); text-decoration: none; }
a:hover { color: var(--brand-deep); }

h1, h2, h3, h4 { margin: 0; font-weight: 700; line-height: 1.25; letter-spacing: -0.2px; }
p { margin: 0; }
ul { margin: 0; padding: 0; list-style: none; }

:focus-visible {
  outline: 2px solid var(--brand);
  outline-offset: 2px;
  border-radius: var(--r-xs);
}

.skip {
  position: absolute; left: -9999px; top: 0;
  background: var(--brand); color: #fff; padding: 10px 16px;
  border-radius: 0 0 var(--r-sm) 0; z-index: 999;
}
.skip:focus { left: 0; }

/* ==================== 2. 版心 / 导航 ==================== */
.wrap {
  width: 100%;
  max-width: var(--container);
  margin: 0 auto;
  padding: 0 var(--gutter);
}

.nav {
  position: fixed; top: 0; left: 0; right: 0; z-index: 60;
  height: var(--nav-h);
  background: rgba(255, 255, 255, 0.82);
  backdrop-filter: saturate(180%) blur(14px);
  -webkit-backdrop-filter: saturate(180%) blur(14px);
  border-bottom: 1px solid var(--line);
}
.nav-inner {
  height: var(--nav-h);
  display: flex; align-items: center; gap: var(--sp-6);
}
.nav-brand { display: flex; align-items: center; gap: 10px; color: var(--text); flex-shrink: 0; }
.nav-brand:hover { color: var(--text); }
.nav-mark { width: 30px; height: 30px; flex-shrink: 0; }
.nav-name { font-size: var(--fs-lg); font-weight: 700; letter-spacing: -0.3px; }

.nav-links { display: flex; align-items: center; gap: 4px; margin-left: auto; }
.nav-link {
  padding: 8px 12px; border-radius: var(--r-sm);
  color: var(--text-sub); font-size: var(--fs-md); font-weight: 500;
  transition: color var(--dur) var(--ease), background var(--dur) var(--ease);
}
.nav-link:hover { color: var(--text); background: var(--surface-muted); }
.nav-link.is-active { color: var(--brand); background: var(--brand-soft); }
.nav-cta { margin-left: var(--sp-4); }

.nav-burger {
  display: none; margin-left: auto;
  width: 40px; height: 40px; border: 0; background: transparent;
  border-radius: var(--r-sm); cursor: pointer;
  align-items: center; justify-content: center; flex-direction: column; gap: 5px;
}
.nav-burger span {
  display: block; width: 20px; height: 2px; border-radius: 2px;
  background: var(--text-sub); transition: transform var(--dur) var(--ease), opacity var(--dur) var(--ease);
}
.nav-burger[aria-expanded="true"] span:nth-child(1) { transform: translateY(7px) rotate(45deg); }
.nav-burger[aria-expanded="true"] span:nth-child(2) { opacity: 0; }
.nav-burger[aria-expanded="true"] span:nth-child(3) { transform: translateY(-7px) rotate(-45deg); }

.nav-mobile {
  display: none;
  position: fixed; top: var(--nav-h); left: 0; right: 0; z-index: 59;
  background: var(--card); border-bottom: 1px solid var(--line);
  padding: var(--sp-4) var(--gutter) var(--sp-5);
  box-shadow: var(--sh-2);
}
.nav-mobile.is-open { display: block; }
.nav-mobile a {
  display: block; padding: 12px 4px; color: var(--text-sub); font-size: var(--fs-lg);
  border-bottom: 1px solid var(--line);
}
.nav-mobile a:last-of-type { border-bottom: 0; }
.nav-mobile a.is-active { color: var(--brand); font-weight: 600; }
.nav-mobile .btn { margin-top: var(--sp-4); }

/* ==================== 3. 按钮 ==================== */
.btn {
  display: inline-flex; align-items: center; justify-content: center; gap: 8px;
  height: 42px; padding: 0 22px;
  border: 1px solid transparent; border-radius: var(--r-pill);
  font-family: inherit; font-size: var(--fs-md); font-weight: 600;
  cursor: pointer; white-space: nowrap;
  transition: transform var(--dur) var(--ease), background var(--dur) var(--ease),
    box-shadow var(--dur) var(--ease), border-color var(--dur) var(--ease);
}
.btn:active { transform: scale(0.97); }
.btn-primary { background: var(--brand); color: #fff; box-shadow: var(--sh-brand); }
.btn-primary:hover { background: var(--brand-deep); color: #fff; }
.btn-ghost { background: transparent; color: var(--text-sub); border-color: var(--line-strong); }
.btn-ghost:hover { color: var(--text); border-color: var(--text-faint); background: var(--card); }
.btn-soft { background: var(--brand-soft); color: var(--brand); }
.btn-soft:hover { background: #DCE8FF; color: var(--brand-deep); }
.btn-lg { height: 50px; padding: 0 30px; font-size: var(--fs-lg); }
.btn-sm { height: 34px; padding: 0 16px; font-size: var(--fs-sm); }
.btn-block { width: 100%; }
.btn[disabled], .btn.is-disabled {
  opacity: 0.45; pointer-events: none; box-shadow: none;
}
.btn.is-done { color: var(--success); border-color: var(--success-soft); background: var(--success-soft); }

code {
  font-family: ui-monospace, SFMono-Regular, Menlo, Consolas, monospace;
  font-size: 0.94em; background: var(--surface-muted); color: var(--brand-deep);
  padding: 2px 6px; border-radius: var(--r-xs);
}

/* ==================== 4. 首屏 ==================== */
.hero {
  position: relative; overflow: hidden;
  padding: calc(var(--nav-h) + clamp(40px, 6vw, 84px)) 0 clamp(48px, 6vw, 92px);
  background:
    radial-gradient(900px 420px at 12% -10%, rgba(59, 124, 255, 0.16), transparent 62%),
    radial-gradient(760px 380px at 92% 4%, rgba(139, 123, 255, 0.14), transparent 60%),
    linear-gradient(180deg, var(--brand-tint), var(--bg) 78%);
}
.hero-grid {
  display: grid; grid-template-columns: minmax(0, 1.05fr) minmax(0, 0.95fr);
  gap: clamp(28px, 4vw, 56px); align-items: center;
}
.hero-eyebrow {
  display: inline-flex; align-items: center; gap: 8px;
  height: 30px; padding: 0 14px; margin-bottom: var(--sp-5);
  background: var(--card); border: 1px solid var(--border-soft);
  border-radius: var(--r-pill);
  color: var(--brand); font-size: var(--fs-sm); font-weight: 600;
  box-shadow: var(--sh-1);
}
.hero-eyebrow .dot { width: 6px; height: 6px; border-radius: 50%; background: var(--brand); }
.hero-title { font-size: var(--fs-h1); letter-spacing: -1px; }
.hero-title em { font-style: normal; color: var(--brand); }
.hero-lead {
  margin-top: var(--sp-5);
  font-size: var(--fs-lead); color: var(--text-sub); line-height: 1.7;
  max-width: 34em;
}
.hero-actions { display: flex; flex-wrap: wrap; gap: var(--sp-4); margin-top: var(--sp-6); }
.hero-note {
  margin-top: var(--sp-5);
  display: flex; flex-wrap: wrap; gap: var(--sp-5);
  font-size: var(--fs-sm); color: var(--text-weak);
}
.hero-note span { display: inline-flex; align-items: center; gap: 6px; }
.hero-note svg { flex-shrink: 0; }

/* ==================== 5. 通用区块 ==================== */
.section { padding: var(--sec-y) 0; }
.section--card { background: var(--card); }
.section--ink {
  background: var(--ink); color: #fff;
}
.section--ink .h2 { color: #fff; }
.section--ink .lead { color: var(--ink-sub); }

.section-head { max-width: 42em; margin-bottom: clamp(28px, 3.4vw, 48px); }
.section-head.center { margin-left: auto; margin-right: auto; text-align: center; }

.eyebrow {
  display: block; margin-bottom: 10px;
  color: var(--brand); font-size: var(--fs-sm); font-weight: 700;
  letter-spacing: 1.4px; text-transform: uppercase;
}
.h2 { font-size: var(--fs-h2); letter-spacing: -0.6px; }
.h3 { font-size: var(--fs-h3); }
.lead { margin-top: var(--sp-4); color: var(--text-sub); font-size: var(--fs-lead); line-height: 1.7; }
.sub { margin-top: var(--sp-3); color: var(--text-weak); font-size: var(--fs-sm); }

.grid { display: grid; gap: var(--sp-5); }
.g-2 { grid-template-columns: repeat(2, minmax(0, 1fr)); }
.g-3 { grid-template-columns: repeat(3, minmax(0, 1fr)); }
.g-4 { grid-template-columns: repeat(4, minmax(0, 1fr)); }

/* ==================== 6. 卡片 ==================== */
.card {
  background: var(--card); border: 1px solid var(--border-soft);
  border-radius: var(--r-lg); padding: var(--sp-6);
  box-shadow: var(--sh-1);
  transition: transform var(--dur) var(--ease), box-shadow var(--dur) var(--ease),
    border-color var(--dur) var(--ease);
}
.card--hover:hover { transform: translateY(-3px); box-shadow: var(--sh-2); border-color: #DDE4F0; }
.card--flat { box-shadow: none; }
.card-title { font-size: var(--fs-lg); font-weight: 700; margin-bottom: var(--sp-3); }
.card-text { color: var(--text-sub); font-size: var(--fs-md); line-height: 1.7; }

.icon-badge {
  width: 46px; height: 46px; border-radius: var(--r-md);
  display: flex; align-items: center; justify-content: center;
  margin-bottom: var(--sp-5); flex-shrink: 0;
}
.icon-badge svg { width: 24px; height: 24px; }
.ib-brand { background: var(--brand-soft); color: var(--brand); }
.ib-violet { background: #F0EDFF; color: var(--kid-violet); }
.ib-orange { background: #FFF1E6; color: var(--kid-orange); }
.ib-mint { background: #E4F8F3; color: #1FA88D; }
.ib-amber { background: #FFF6E2; color: #C97F00; }

.points { margin-top: var(--sp-5); display: flex; flex-direction: column; gap: 10px; }
.point {
  display: flex; gap: 10px; align-items: flex-start;
  color: var(--text-sub); font-size: var(--fs-sm); line-height: 1.6;
}
.point svg { flex-shrink: 0; margin-top: 3px; }

/* ==================== 7. 手机示意（纯 CSS 绘制，非素材图） ==================== */
.phone {
  width: 100%; max-width: 306px; margin: 0 auto;
  background: #1B1F2A; border-radius: 34px; padding: 9px;
  box-shadow: 0 22px 50px rgba(20, 24, 33, 0.22), 0 2px 0 rgba(255, 255, 255, 0.06) inset;
}
.phone-screen {
  position: relative; background: #F2F5FF;
  border-radius: 26px; overflow: hidden; min-height: 470px;
  display: flex; flex-direction: column;
}
.pm-head {
  padding: 20px 16px 46px;
  background: linear-gradient(150deg, #3B7CFF, #6E7BFF 62%, #8B7BFF);
  color: #fff;
  border-radius: 0 0 20px 20px;
}
.pm-head-row { display: flex; align-items: center; justify-content: space-between; }
.pm-avatar {
  width: 34px; height: 34px; border-radius: 50%;
  background: rgba(255, 255, 255, 0.22);
  display: flex; align-items: center; justify-content: center;
  font-size: 12px; font-weight: 700;
}
.pm-greet { font-size: 13px; opacity: 0.86; margin-top: 12px; }
.pm-title { font-size: 17px; font-weight: 700; margin-top: 3px; }
.pm-glass {
  display: grid; grid-template-columns: repeat(3, 1fr); gap: 8px;
  margin: -32px 12px 0; padding: 12px 10px;
  background: rgba(255, 255, 255, 0.72);
  border: 1px solid rgba(255, 255, 255, 0.9);
  border-radius: 14px; box-shadow: var(--sh-2);
  backdrop-filter: blur(8px);
}
.pm-glass div { text-align: center; }
.pm-glass b { display: block; font-size: 15px; color: var(--text); font-variant-numeric: tabular-nums; }
.pm-glass span { font-size: 10px; color: var(--text-weak); }
.pm-body { padding: 12px; display: flex; flex-direction: column; gap: 10px; flex: 1; }
.pm-card {
  background: #fff; border-radius: 12px; padding: 11px 12px;
  box-shadow: var(--sh-1);
}
.pm-card-title { font-size: 12px; font-weight: 700; color: var(--text); }
.pm-card-sub { font-size: 10px; color: var(--text-weak); margin-top: 2px; }
.pm-bar { height: 6px; background: #EDF0F6; border-radius: 999px; overflow: hidden; margin-top: 9px; }
.pm-bar i { display: block; height: 100%; border-radius: 999px; background: linear-gradient(90deg, var(--brand), var(--kid-violet)); }
.pm-bubble {
  align-self: flex-start; max-width: 84%;
  background: #fff; border-radius: 12px 12px 12px 4px;
  padding: 8px 11px; font-size: 11px; color: var(--text-sub); line-height: 1.6;
  box-shadow: var(--sh-1);
}
.pm-tabbar {
  display: grid; grid-template-columns: repeat(4, 1fr);
  background: #fff; border-top: 1px solid var(--line); padding: 8px 0 10px;
}
.pm-tabbar div { text-align: center; font-size: 9px; color: var(--text-faint); }
.pm-tabbar div b { display: block; font-size: 14px; margin-bottom: 2px; font-weight: 400; }
.pm-tabbar .on { color: var(--brand); font-weight: 600; }

/* ==================== 8. 上课演示（数字人画面，纯 CSS 绘制） ==================== */
.phone-screen--dark { background: #171A21; }
.pc-stage {
  flex: 1; display: flex; flex-direction: column;
  align-items: center; justify-content: center; gap: 14px; padding: 26px 16px;
}
.pc-face {
  width: 92px; height: 92px; border-radius: 50%;
  background: linear-gradient(150deg, #3B7CFF, #8B7BFF);
  display: flex; align-items: center; justify-content: center; color: #fff;
  box-shadow: 0 0 0 8px rgba(59, 124, 255, 0.14);
}
.pc-face svg { width: 40px; height: 40px; }
.pc-name { color: #fff; font-size: 13px; font-weight: 600; }
.pc-tip { color: #8B93A6; font-size: 11px; line-height: 1.7; text-align: center; max-width: 15em; }
.pc-wave { display: flex; align-items: flex-end; gap: 4px; height: 22px; }
.pc-wave i {
  width: 3px; height: 6px; border-radius: 2px; background: var(--brand);
  animation: pc-wave 1s var(--ease) infinite;
}
@keyframes pc-wave {
  0%, 100% { height: 6px; opacity: 0.45; }
  50% { height: 20px; opacity: 1; }
}
.pc-ctrl { display: flex; justify-content: center; gap: 14px; padding: 0 0 22px; }
.pc-ctrl span {
  width: 44px; height: 44px; border-radius: 50%;
  background: rgba(255, 255, 255, 0.10); color: #fff;
  display: flex; align-items: center; justify-content: center;
}
.pc-ctrl span svg { width: 19px; height: 19px; }
.pc-ctrl .hangup { background: var(--danger); }

/* 深色区块内的要点列表 */
.ink-points { display: grid; gap: var(--sp-4); margin-top: var(--sp-6); }
.ink-point { display: flex; gap: 12px; align-items: flex-start; }
.ink-point svg { flex-shrink: 0; margin-top: 4px; color: var(--brand); }
.ink-point b { display: block; color: #fff; font-size: var(--fs-md); margin-bottom: 3px; }
.ink-point p { color: var(--ink-sub); font-size: var(--fs-sm); line-height: 1.75; }

/* ==================== 9. 下载页 ==================== */
.dl-hero { padding-top: calc(var(--nav-h) + clamp(36px, 5vw, 64px)); }
.ua-banner {
  display: flex; align-items: center; gap: 12px; flex-wrap: wrap;
  padding: 14px var(--sp-5); margin-bottom: var(--sp-5);
  background: var(--brand-soft); border: 1px solid #D6E4FF;
  border-radius: var(--r-md); color: var(--brand-deep); font-size: var(--fs-sm);
}
.ua-banner b { font-weight: 700; }
.ua-banner svg { flex-shrink: 0; }

.dl-layout { display: grid; grid-template-columns: minmax(0, 1fr) 320px; gap: var(--sp-5); align-items: start; }

.dl-card {
  background: var(--card); border: 2px solid var(--brand);
  border-radius: var(--r-lg); padding: clamp(20px, 2.6vw, 32px);
  box-shadow: var(--sh-2); position: relative; overflow: hidden;
}
.dl-card::after {
  content: ""; position: absolute; inset: 0;
  background: radial-gradient(420px 200px at 100% 0, rgba(59, 124, 255, 0.08), transparent 70%);
  pointer-events: none;
}
.dl-card-head { display: flex; align-items: center; gap: 14px; flex-wrap: wrap; position: relative; }
.dl-card-head .icon-badge { margin-bottom: 0; background: var(--brand); color: #fff; }
.dl-name { font-size: var(--fs-xl); font-weight: 700; }
.dl-tag {
  display: inline-flex; align-items: center; gap: 5px;
  height: 24px; padding: 0 10px; border-radius: var(--r-pill);
  background: var(--success-soft); color: var(--success);
  font-size: var(--fs-xs); font-weight: 700;
}
.dl-ver { color: var(--text-weak); font-size: var(--fs-sm); margin-top: 4px; }

.dl-meta {
  display: grid; grid-template-columns: repeat(3, minmax(0, 1fr));
  gap: var(--sp-4); margin: var(--sp-6) 0;
  position: relative;
}
.dl-meta div { padding: 12px 14px; background: var(--surface-muted); border-radius: var(--r-sm); }
.dl-meta dt { font-size: var(--fs-xs); color: var(--text-weak); }
.dl-meta dd { margin: 4px 0 0; font-size: var(--fs-md); font-weight: 700; color: var(--text); font-variant-numeric: tabular-nums; }

/* 两张下载卡并排；JS 按机型决定显隐与主次 */
.dl-pair { display: grid; grid-template-columns: repeat(2, minmax(0, 1fr)); gap: var(--sp-5); align-items: start; margin-bottom: var(--sp-5); }
.dl-card--muted { border-width: 1px; border-color: var(--border-soft); box-shadow: var(--sh-1); }
.dl-card--muted::after { display: none; }
[hidden] { display: none !important; }

.dl-actions { display: flex; flex-wrap: wrap; gap: var(--sp-4); position: relative; }
.dl-hint { margin-top: var(--sp-5); font-size: var(--fs-sm); color: var(--text-weak); position: relative; }

.dl-side { display: grid; gap: var(--sp-4); }
.dl-mini {
  background: var(--card); border: 1px solid var(--border-soft);
  border-radius: var(--r-md); padding: var(--sp-5);
}
.dl-mini h3 { font-size: var(--fs-md); margin-bottom: var(--sp-4); }
.dl-mini .row {
  display: flex; justify-content: space-between; gap: 10px;
  font-size: var(--fs-sm); color: var(--text-sub);
  padding: 7px 0; border-bottom: 1px dashed var(--line);
}
.dl-mini .row:last-child { border-bottom: 0; }
.dl-mini .row b { color: var(--text); font-weight: 600; }

.hash {
  font-family: ui-monospace, SFMono-Regular, Menlo, Consolas, monospace;
  font-size: var(--fs-xs); color: var(--text-sub); word-break: break-all;
  background: var(--surface-muted); border-radius: var(--r-sm);
  padding: 10px 12px; line-height: 1.7;
}

.tabs { display: flex; flex-wrap: wrap; gap: var(--sp-2); margin-bottom: var(--sp-5); }
.tab {
  height: 38px; padding: 0 18px; border-radius: var(--r-pill);
  border: 1px solid var(--line-strong); background: var(--card);
  color: var(--text-sub); font-family: inherit; font-size: var(--fs-sm); font-weight: 600;
  cursor: pointer; transition: all var(--dur) var(--ease);
}
.tab:hover { color: var(--text); border-color: var(--text-faint); }
.tab.is-active { background: var(--brand); border-color: var(--brand); color: #fff; box-shadow: var(--sh-brand); }
.tab-body { display: none; }
.tab-body.is-active { display: block; }

.steps { counter-reset: s; display: grid; gap: var(--sp-4); }
.step {
  display: flex; gap: 14px; align-items: flex-start;
  background: var(--card); border: 1px solid var(--border-soft);
  border-radius: var(--r-md); padding: var(--sp-5);
}
.step::before {
  counter-increment: s; content: counter(s);
  width: 26px; height: 26px; border-radius: 50%; flex-shrink: 0;
  background: var(--brand-soft); color: var(--brand);
  display: flex; align-items: center; justify-content: center;
  font-size: var(--fs-sm); font-weight: 700;
}
.step b { display: block; font-size: var(--fs-md); margin-bottom: 3px; }
.step p { color: var(--text-sub); font-size: var(--fs-sm); line-height: 1.7; }
.step code {
  font-family: ui-monospace, SFMono-Regular, Menlo, Consolas, monospace;
  font-size: var(--fs-xs); background: var(--surface-muted);
  padding: 2px 6px; border-radius: var(--r-xs); color: var(--brand-deep);
}

.note {
  display: flex; gap: 10px; align-items: flex-start;
  padding: 14px var(--sp-5); border-radius: var(--r-md);
  background: var(--warn-soft); color: #8A4A10; font-size: var(--fs-sm); line-height: 1.7;
}
.note svg { flex-shrink: 0; margin-top: 3px; color: var(--warn); }

/* ==================== 10. 折叠问答 ==================== */
.faq-list { display: grid; gap: var(--sp-4); }
.faq-item {
  background: var(--card); border: 1px solid var(--border-soft);
  border-radius: var(--r-md); overflow: hidden;
}
.faq-q {
  width: 100%; display: flex; align-items: center; gap: var(--sp-4);
  padding: var(--sp-5); border: 0; background: transparent;
  font-family: inherit; font-size: var(--fs-md); font-weight: 600; color: var(--text);
  text-align: left; cursor: pointer;
}
.faq-q span { flex: 1; }
.faq-q svg { flex-shrink: 0; color: var(--text-weak); transition: transform var(--dur) var(--ease); }
.faq-q[aria-expanded="true"] svg { transform: rotate(180deg); }
.faq-a {
  display: none; padding: 0 var(--sp-5) var(--sp-5);
  color: var(--text-sub); font-size: var(--fs-sm); line-height: 1.8;
}
.faq-a.is-open { display: block; }
.faq-a p + p { margin-top: 10px; }

/* ==================== 11. 客服 ==================== */
.fab {
  position: fixed; right: 20px; bottom: 20px; z-index: 70;
  width: 54px; height: 54px; border-radius: 50%;
  border: 0; cursor: pointer; color: #fff;
  background: var(--brand); box-shadow: 0 8px 22px rgba(59, 124, 255, 0.36);
  display: flex; align-items: center; justify-content: center;
  transition: transform var(--dur) var(--ease), background var(--dur) var(--ease);
}
.fab:hover { background: var(--brand-deep); transform: translateY(-2px); }
.fab svg { width: 24px; height: 24px; }
.fab-dot {
  position: absolute; top: 2px; right: 2px;
  width: 11px; height: 11px; border-radius: 50%;
  background: var(--kid-orange); border: 2px solid #fff;
}

.support-panel {
  position: fixed; right: 20px; bottom: 86px; z-index: 70;
  width: min(376px, calc(100vw - 32px));
  max-height: min(620px, calc(100vh - 128px));
  display: none; flex-direction: column; overflow: hidden;
  background: var(--card); border: 1px solid var(--border-soft);
  border-radius: var(--r-lg); box-shadow: 0 18px 48px rgba(20, 24, 33, 0.18);
}
.support-panel.is-open { display: flex; }

.support-head {
  display: flex; align-items: center; gap: 10px;
  padding: 14px var(--sp-5);
  background: linear-gradient(135deg, var(--brand), #6E7BFF);
  color: #fff;
}
.support-head b { font-size: var(--fs-md); }
.support-head p { font-size: var(--fs-xs); opacity: 0.82; margin-top: 2px; }
.support-head .icon-badge {
  margin: 0; width: 34px; height: 34px; background: rgba(255, 255, 255, 0.2); color: #fff;
}
.support-close {
  margin-left: auto; width: 30px; height: 30px; border: 0; border-radius: 50%;
  background: rgba(255, 255, 255, 0.16); color: #fff; cursor: pointer;
  display: flex; align-items: center; justify-content: center;
}
.support-close svg { width: 15px; height: 15px; }
.support-close:hover { background: rgba(255, 255, 255, 0.28); }

.support-tabs { display: flex; border-bottom: 1px solid var(--line); background: var(--card); }
.support-tab {
  flex: 1; padding: 12px 0; border: 0; background: transparent;
  font-family: inherit; font-size: var(--fs-sm); font-weight: 600; color: var(--text-weak);
  cursor: pointer; border-bottom: 2px solid transparent;
}
.support-tab.is-active { color: var(--brand); border-bottom-color: var(--brand); }

.support-body { flex: 1; overflow-y: auto; padding: var(--sp-5); }
.support-pane { display: none; }
.support-pane.is-active { display: block; }

.chat-log { display: flex; flex-direction: column; gap: var(--sp-4); }
.msg { max-width: 86%; padding: 10px 13px; border-radius: 14px; font-size: var(--fs-sm); line-height: 1.7; white-space: pre-wrap; word-break: break-word; }
.msg-bot { align-self: flex-start; background: var(--surface-muted); color: var(--text-sub); border-bottom-left-radius: 4px; }
.msg-user { align-self: flex-end; background: var(--brand); color: #fff; border-bottom-right-radius: 4px; }
.msg-sys { align-self: stretch; max-width: 100%; background: var(--warn-soft); color: #8A4A10; font-size: var(--fs-xs); border-radius: var(--r-sm); }
.msg .caret {
  display: inline-block; width: 6px; height: 13px; margin-left: 2px;
  background: var(--brand); vertical-align: -2px; border-radius: 1px;
  animation: caret-blink 1s steps(1) infinite;
}
@keyframes caret-blink { 50% { opacity: 0; } }

.chat-form { display: flex; gap: var(--sp-3); padding: var(--sp-4) var(--sp-5); border-top: 1px solid var(--line); }
.chat-input {
  flex: 1; min-width: 0; height: 40px; padding: 0 14px;
  border: 1px solid var(--line-strong); border-radius: var(--r-pill);
  font-family: inherit; font-size: var(--fs-sm); color: var(--text);
  background: var(--card);
}
.chat-input:focus { outline: none; border-color: var(--brand); box-shadow: 0 0 0 3px var(--brand-soft); }
.chat-send {
  width: 40px; height: 40px; flex-shrink: 0; border: 0; border-radius: 50%;
  background: var(--brand); color: #fff; cursor: pointer;
  display: flex; align-items: center; justify-content: center;
}
.chat-send:hover { background: var(--brand-deep); }
.chat-send[disabled] { opacity: 0.45; cursor: not-allowed; }

.qr-box {
  border: 2px dashed var(--line-strong); border-radius: var(--r-md);
  padding: var(--sp-6) var(--sp-5); text-align: center;
  background: var(--surface-muted); color: var(--text-weak); font-size: var(--fs-sm);
}
.qr-box img { width: 176px; height: 176px; margin: 0 auto var(--sp-4); border-radius: var(--r-sm); }
.qr-box b { display: block; color: var(--text); font-size: var(--fs-md); margin-bottom: 4px; }
.hours { margin-top: var(--sp-5); display: grid; gap: 8px; font-size: var(--fs-sm); color: var(--text-sub); }
.hours .row { display: flex; justify-content: space-between; padding: 7px 0; border-bottom: 1px dashed var(--line); }
.hours .row:last-child { border-bottom: 0; }

/* ==================== 12. 法务 / 文档 ==================== */
.doc { max-width: var(--container-narrow); margin: 0 auto; }
.doc h2 {
  font-size: var(--fs-h3); margin: var(--sp-6) 0 var(--sp-4);
  padding-top: var(--sp-5); border-top: 1px solid var(--line);
}
.doc h2:first-of-type { border-top: 0; padding-top: 0; margin-top: var(--sp-6); }
.doc p { color: var(--text-sub); font-size: var(--fs-md); line-height: 1.9; margin-bottom: var(--sp-4); }
.doc ul { margin: 0 0 var(--sp-4); padding-left: 0; display: grid; gap: 8px; }
.doc ul li {
  position: relative; padding-left: 18px; color: var(--text-sub);
  font-size: var(--fs-md); line-height: 1.9;
}
.doc ul li::before {
  content: ""; position: absolute; left: 2px; top: 12px;
  width: 5px; height: 5px; border-radius: 50%; background: var(--text-faint);
}
.doc .callout {
  padding: var(--sp-5); border-left: 3px solid var(--brand);
  background: var(--brand-tint); border-radius: 0 var(--r-sm) var(--r-sm) 0;
  color: var(--text-sub); font-size: var(--fs-sm); line-height: 1.8;
  margin-bottom: var(--sp-5);
}
.doc-meta { color: var(--text-weak); font-size: var(--fs-sm); margin-top: var(--sp-3); }

/* ==================== 13. 页脚 ==================== */
.footer { background: var(--ink); color: var(--ink-sub); padding: clamp(40px, 5vw, 64px) 0 var(--sp-6); }
.footer-grid {
  display: grid; grid-template-columns: minmax(0, 1.4fr) repeat(3, minmax(0, 1fr));
  gap: clamp(24px, 3vw, 48px);
}
.footer-brand .nav-name { color: #fff; }
.footer-brand .nav-mark { color: var(--brand); }
.footer-desc { margin-top: var(--sp-4); font-size: var(--fs-sm); line-height: 1.8; max-width: 26em; }
.footer h4 { color: #fff; font-size: var(--fs-sm); margin-bottom: var(--sp-4); letter-spacing: 0.4px; }
.footer-col a { display: block; color: var(--ink-sub); font-size: var(--fs-sm); padding: 5px 0; }
.footer-col a:hover { color: #fff; }
.footer-bottom {
  margin-top: clamp(28px, 3vw, 44px); padding-top: var(--sp-5);
  border-top: 1px solid var(--ink-line);
  display: flex; flex-wrap: wrap; gap: var(--sp-3) var(--sp-5);
  align-items: center; font-size: var(--fs-xs);
}
.footer-bottom .spacer { margin-left: auto; }
.footer-bottom a { color: var(--ink-sub); }
.footer-bottom a:hover { color: #fff; }

/* ==================== 14. 入场动效 ==================== */
.reveal { opacity: 0; transform: translateY(16px); }
.reveal.is-in {
  opacity: 1; transform: none;
  transition: opacity 520ms var(--ease), transform 520ms var(--ease);
}
@media (prefers-reduced-motion: reduce) {
  html { scroll-behavior: auto; }
  .reveal { opacity: 1; transform: none; }
  .btn:active { transform: none; }
  .card--hover:hover { transform: none; }
}

/* ==================== 16. 产品能力页的示意卡（纯 CSS 绘制） ==================== */
.feat-row { display: grid; grid-template-columns: repeat(2, minmax(0, 1fr)); gap: clamp(24px, 4vw, 56px); align-items: center; }
.feat-row + .feat-row { margin-top: clamp(44px, 5vw, 76px); }
.feat-copy .card-title { margin-top: var(--sp-4); font-size: var(--fs-h3); }

.mock {
  background: var(--surface-muted); border: 1px solid var(--border-soft);
  border-radius: var(--r-lg); padding: var(--sp-5);
}
.mock-head {
  display: flex; align-items: center; justify-content: space-between;
  padding-bottom: var(--sp-4); margin-bottom: var(--sp-4);
  border-bottom: 1px solid var(--line);
  font-size: var(--fs-sm); font-weight: 700; color: var(--text);
}
.mock-head span { font-size: var(--fs-xs); font-weight: 500; color: var(--text-weak); }

.mock-row {
  display: flex; align-items: center; gap: 10px;
  background: var(--card); border-radius: var(--r-sm);
  padding: 11px 13px; margin-bottom: var(--sp-3);
  box-shadow: var(--sh-1); font-size: var(--fs-sm);
}
.mock-row:last-child { margin-bottom: 0; }
.mock-row .tick {
  width: 18px; height: 18px; border-radius: 50%; flex-shrink: 0;
  display: flex; align-items: center; justify-content: center;
  background: var(--brand-soft); color: var(--brand);
}
.mock-row .tick svg { width: 11px; height: 11px; }
.mock-row--done .tick { background: var(--success-soft); color: var(--success); }
.mock-row--done .lbl { color: var(--text-faint); text-decoration: line-through; }
.mock-row .lbl { flex: 1; color: var(--text-sub); }
.mock-row .val { color: var(--text-weak); font-size: var(--fs-xs); white-space: nowrap; }

.mock-tree { position: relative; padding-left: 18px; }
.mock-tree::before {
  content: ""; position: absolute; left: 5px; top: 8px; bottom: 8px;
  border-left: 2px dashed var(--line-strong);
}
.mock-node {
  position: relative; background: var(--card); border-radius: var(--r-sm);
  padding: 9px 12px; margin-bottom: var(--sp-3); box-shadow: var(--sh-1);
  font-size: var(--fs-sm); display: flex; align-items: center; gap: 8px;
}
.mock-node::before {
  content: ""; position: absolute; left: -13px; top: 50%; width: 12px;
  border-top: 2px dashed var(--line-strong);
}
.mock-node .nid {
  width: 20px; height: 20px; border-radius: 50%; flex-shrink: 0;
  display: flex; align-items: center; justify-content: center;
  font-size: 10px; font-weight: 700;
  background: #F1F3F8; color: var(--text-faint);
}
.mock-node--lit .nid { background: var(--success-soft); color: var(--success); }
.mock-node--lit .nname { color: var(--text); font-weight: 600; }
.mock-node--plan .nid { background: var(--brand-soft); color: var(--brand); }
.mock-node .nname { color: var(--text-weak); }

.mock-bars { display: grid; gap: 10px; }
.mock-bar-row { display: flex; align-items: center; gap: 10px; font-size: var(--fs-xs); color: var(--text-weak); }
.mock-bar-row .bl { width: 42px; flex-shrink: 0; }
.mock-bar-row .bt { flex: 1; height: 9px; background: #EAEEF6; border-radius: var(--r-pill); overflow: hidden; }
.mock-bar-row .bt i { display: block; height: 100%; border-radius: var(--r-pill); background: var(--brand); }
.mock-bar-row .bv { width: 30px; text-align: right; color: var(--text-sub); font-variant-numeric: tabular-nums; }

@media (max-width: 860px) {
  .feat-row { grid-template-columns: 1fr; }
}

@media (max-width: 1024px) {
  .hero-grid { grid-template-columns: 1fr; }
  .hero-visual { margin-top: var(--sp-4); }
  .dl-layout { grid-template-columns: 1fr; }
  .footer-grid { grid-template-columns: repeat(2, minmax(0, 1fr)); }
  .g-4 { grid-template-columns: repeat(2, minmax(0, 1fr)); }
}

@media (max-width: 860px) {
  .nav-links { display: none; }
  .nav-cta { display: none; }
  .nav-burger { display: flex; }
  .g-3 { grid-template-columns: repeat(2, minmax(0, 1fr)); }
  .dl-pair { grid-template-columns: 1fr; }
}

@media (max-width: 640px) {
  :root { --gutter: 18px; }
  .g-2, .g-3, .g-4 { grid-template-columns: 1fr; }
  .dl-meta { grid-template-columns: repeat(2, minmax(0, 1fr)); }
  .footer-grid { grid-template-columns: 1fr; }
  .hero-actions .btn { width: 100%; }
  .support-panel {
    right: 12px; left: 12px; bottom: 80px; width: auto;
    max-height: calc(100vh - 110px);
  }
  .fab { right: 14px; bottom: 14px; }
}