/* =========================================================
   cleanpath-huatihui.com.cn — 共享样式表 /assets/site.css
   0. Reset
   1. 设计变量
   2. 基础排版
   3. 容器 / 分区 / 网格
   4. 编号章节与通用文本组件
   5. 卡片 · 档案夹 · 资料卡 · 标签
   6. 数据表 · 时间轴 · 对比条
   7. 按钮 · 面包屑 · 提示 · 图片容器
   8. 页头
   9. 页脚
   10. 动效 · 显现 · 无障碍
   ========================================================= */

/* ---------- 0. Reset ---------- */
*,
*::before,
*::after { box-sizing: border-box; }

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

body,
h1, h2, h3, h4, h5,
p, ul, ol, li, figure, blockquote, dl, dd { margin: 0; }

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

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

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

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

table { border-collapse: collapse; }

::selection { background: var(--orange); color: #fff; }

/* ---------- 1. 设计变量 ---------- */
:root {
  --navy-900: #0A1A31;
  --navy-800: #12305A;
  --blue-600: #1F63C4;
  --blue-100: #DCE8F8;
  --orange: #FF6A1A;
  --orange-hover: #FF7E36;
  --orange-deep: #B4430A;
  --orange-100: #FFE3D0;
  --amber: #FFB020;
  --amber-100: #FFF3D6;
  --amber-ink: #7A4E00;
  --teal: #0E8A66;
  --teal-100: #DCF3EC;
  --teal-ink: #065C45;
  --paper: #F4F6F9;
  --white: #FFFFFF;
  --line: #D7DDE6;
  --ink: #131C2B;
  --muted: #5C6A7C;

  --font-sans: system-ui, -apple-system, "Segoe UI", "Noto Sans SC", "PingFang SC",
    "Hiragino Sans GB", "Microsoft YaHei", sans-serif;
  --font-mono: ui-monospace, "SFMono-Regular", "Roboto Mono", Menlo, Consolas,
    "Liberation Mono", monospace;

  --r-sm: 10px;
  --r-md: 18px;
  --r-lg: 28px;
  --r-xl: 38px;
  --r-pill: 999px;

  --shadow-1: 0 2px 4px rgba(10, 26, 49, .05), 0 12px 26px -20px rgba(10, 26, 49, .45);
  --shadow-2: 0 20px 44px -24px rgba(10, 26, 49, .5);
  --shadow-bar: 0 18px 40px -26px rgba(10, 26, 49, .9);

  --wrap: 1180px;
  --gutter: clamp(16px, 4vw, 40px);
  --section-y: clamp(46px, 7vw, 92px);
}

/* ---------- 2. 基础排版 ---------- */
body {
  font-family: var(--font-sans);
  font-size: 17px;
  line-height: 1.75;
  color: var(--ink);
  background-color: var(--paper);
  -webkit-font-smoothing: antialiased;
  text-rendering: optimizeLegibility;
}

h1, h2, h3, h4 {
  font-weight: 800;
  line-height: 1.16;
  letter-spacing: -.02em;
  color: var(--navy-900);
}

h1 { font-size: clamp(2.4rem, 6vw, 4.6rem); }
h2 { font-size: clamp(1.5rem, 3vw, 2.2rem); }
h3 { font-size: 1.125rem; }
h4 { font-size: 1rem; }

p { max-width: 68ch; }

strong { font-weight: 700; color: var(--navy-900); }

.mono {
  font-family: var(--font-mono);
  font-variant-numeric: tabular-nums;
  font-weight: 500;
  letter-spacing: -.01em;
}

.num {
  font-family: var(--font-mono);
  font-variant-numeric: tabular-nums;
  font-weight: 700;
  letter-spacing: -.02em;
}

.u-muted { color: var(--muted); }

.link-more {
  display: inline-flex;
  align-items: center;
  gap: 6px;
  font-weight: 700;
  color: var(--blue-600);
  border-bottom: 2px solid transparent;
  transition: border-color .18s ease, color .18s ease;
}
.link-more::after { content: "→"; font-family: var(--font-sans); }
.link-more:hover { color: var(--navy-900); border-color: var(--orange); }

.divider {
  height: 1px;
  background: var(--line);
  border: 0;
  margin: clamp(24px, 4vw, 40px) 0;
}

.notice {
  display: flex;
  gap: 12px;
  align-items: flex-start;
  padding: 16px 20px;
  border-radius: var(--r-md);
  background: var(--orange-100);
  border-left: 4px solid var(--orange);
  font-size: .9375rem;
}
.notice p { max-width: none; }

/* ---------- 3. 容器 / 分区 / 网格 ---------- */
.wrap {
  width: min(var(--wrap), 100%);
  margin-inline: auto;
  padding-inline: var(--gutter);
}

.wrap--narrow { width: min(760px, 100%); }

.section { padding-block: var(--section-y); }
.section--flush-top { padding-top: 0; }

.section-head { margin-bottom: clamp(22px, 3vw, 38px); }
.section-head .section-lead { margin-top: 12px; }

.eyebrow {
  display: inline-flex;
  align-items: center;
  gap: 8px;
  font-size: .8125rem;
  font-weight: 700;
  letter-spacing: .12em;
  text-transform: uppercase;
  color: var(--blue-600);
  margin-bottom: 10px;
}
.eyebrow::before {
  content: "";
  width: 22px;
  height: 3px;
  border-radius: 2px;
  background: var(--orange);
}

.section-title { max-width: 22ch; }

.section-lead {
  font-size: 1.0625rem;
  color: var(--muted);
  max-width: 60ch;
}

.grid {
  display: grid;
  gap: clamp(16px, 2.5vw, 28px);
}
.grid--2 { grid-template-columns: repeat(2, minmax(0, 1fr)); }
.grid--3 { grid-template-columns: repeat(3, minmax(0, 1fr)); }
.grid--split { grid-template-columns: minmax(0, 7fr) minmax(0, 5fr); }

.stack { display: grid; gap: clamp(14px, 2vw, 22px); }
.stack--tight { gap: 10px; }

/* ---------- 4. 编号章节 ---------- */
.chapter {
  position: relative;
  padding-block: clamp(34px, 5vw, 64px);
}

.chapter-head {
  display: grid;
  grid-template-columns: auto minmax(0, 1fr);
  gap: clamp(14px, 2.4vw, 30px);
  align-items: start;
}

.chapter-index {
  font-family: var(--font-mono);
  font-weight: 700;
  font-size: clamp(2.6rem, 6.4vw, 4.6rem);
  line-height: .82;
  letter-spacing: -.05em;
  color: rgba(31, 99, 196, .22);
}

@supports (-webkit-text-stroke: 2px #000) {
  .chapter-index {
    color: transparent;
    -webkit-text-stroke: 2px var(--blue-600);
  }
  .chapter-index--light { -webkit-text-stroke-color: rgba(255, 255, 255, .55); }
}

.chapter-body { padding-top: 6px; }

.chapter-title {
  font-size: clamp(1.5rem, 3vw, 2.2rem);
  margin-bottom: 10px;
}

.chapter-lead {
  color: var(--muted);
  font-size: 1.0625rem;
  max-width: 56ch;
}

/* ---------- 5. 卡片 / 档案夹 / 资料卡 / 标签 ---------- */
.card {
  background: var(--white);
  border: 1px solid var(--line);
  border-radius: var(--r-lg);
  padding: clamp(20px, 3vw, 30px);
  box-shadow: var(--shadow-1);
  transition: transform .2s ease, box-shadow .2s ease, border-color .2s ease;
}
.card:hover,
.card:focus-within {
  transform: translateY(-4px);
  box-shadow: var(--shadow-2);
  border-color: var(--blue-100);
}

.card__title { font-size: 1.125rem; margin-bottom: 8px; }
.card__text { font-size: .9375rem; color: var(--muted); max-width: none; }
.card__meta {
  margin-top: 14px;
  font-size: .8125rem;
  letter-spacing: .06em;
  text-transform: uppercase;
  color: var(--muted);
}
.card__foot {
  margin-top: 18px;
  padding-top: 14px;
  border-top: 1px solid var(--line);
  display: flex;
  flex-wrap: wrap;
  gap: 10px;
  align-items: center;
}

.folder-card {
  position: relative;
  margin-top: 16px;
  background: var(--white);
  border: 1px solid var(--line);
  border-radius: var(--r-sm) var(--r-lg) var(--r-lg) var(--r-lg);
  padding: clamp(22px, 3vw, 30px);
  box-shadow: var(--shadow-1);
  transition: transform .2s ease, box-shadow .2s ease;
}
.folder-card:hover,
.folder-card:focus-within {
  transform: translateY(-4px);
  box-shadow: var(--shadow-2);
}

.folder-card__tab {
  position: absolute;
  top: -15px;
  left: 22px;
  padding: 5px 15px;
  border-radius: var(--r-pill) var(--r-pill) 0 0;
  background: var(--blue-100);
  color: var(--navy-800);
  font-size: .75rem;
  font-weight: 700;
  letter-spacing: .08em;
}

.folder-card__title { font-size: 1.125rem; margin-bottom: 8px; }

.datacard {
  background: var(--white);
  border: 1px solid var(--line);
  border-left: 4px solid var(--orange);
  border-radius: var(--r-md);
  padding: 16px 20px;
  transition: transform .2s ease, box-shadow .2s ease;
}
.datacard:hover,
.datacard:focus-within {
  transform: translateY(-4px);
  box-shadow: var(--shadow-1);
}

.datacard__label {
  font-size: .8125rem;
  font-weight: 700;
  letter-spacing: .08em;
  color: var(--muted);
}

.datacard__value {
  font-family: var(--font-mono);
  font-variant-numeric: tabular-nums;
  font-weight: 700;
  font-size: clamp(1.5rem, 3vw, 2rem);
  line-height: 1.2;
  color: var(--navy-900);
}

.datacard__hint {
  font-size: .875rem;
  color: var(--muted);
  max-width: none;
}

.tag-row {
  display: flex;
  flex-wrap: wrap;
  gap: 8px;
}

.tag {
  display: inline-flex;
  align-items: center;
  gap: 6px;
  padding: 5px 13px;
  border-radius: var(--r-pill);
  background: var(--blue-100);
  color: var(--navy-800);
  font-size: .8125rem;
  font-weight: 700;
  letter-spacing: .03em;
  white-space: nowrap;
}

.tag--orange { background: var(--orange-100); color: var(--orange-deep); }
.tag--amber { background: var(--amber-100); color: var(--amber-ink); }
.tag--teal { background: var(--teal-100); color: var(--teal-ink); }
.tag--dark { background: var(--navy-900); color: #fff; }

/* ---------- 6. 数据表 / 时间轴 / 对比条 ---------- */
.table-wrap {
  overflow-x: auto;
  background: var(--white);
  border: 1px solid var(--line);
  border-radius: var(--r-md);
  box-shadow: var(--shadow-1);
}

.data-table {
  width: 100%;
  min-width: 540px;
  font-size: .9375rem;
}

.data-table caption {
  text-align: left;
  padding: 14px 16px 0;
  font-size: .8125rem;
  letter-spacing: .06em;
  text-transform: uppercase;
  color: var(--muted);
}

.data-table th {
  background: var(--navy-800);
  color: #fff;
  text-align: left;
  font-size: .8125rem;
  font-weight: 700;
  letter-spacing: .06em;
  padding: 12px 16px;
}

.data-table td {
  padding: 13px 16px;
  border-top: 1px solid var(--line);
  vertical-align: top;
}

.data-table tbody tr:nth-child(even) { background: var(--blue-100); }
.data-table tbody tr:hover,
.data-table tbody tr:focus-within { background: var(--orange-100); }
.data-table td .num { color: var(--navy-900); }

.timeline {
  position: relative;
  padding-left: 30px;
}
.timeline::before {
  content: "";
  position: absolute;
  left: 9px;
  top: 8px;
  bottom: 8px;
  width: 2px;
  border-radius: 2px;
  background: rgba(18, 48, 90, .25);
}

.timeline__item {
  position: relative;
  padding-bottom: 26px;
}
.timeline__item:last-child { padding-bottom: 0; }

.timeline__dot {
  position: absolute;
  left: -27px;
  top: 5px;
  width: 16px;
  height: 16px;
  border-radius: 50%;
  background: var(--white);
  border: 2px solid var(--blue-600);
  transition: box-shadow .18s ease, background-color .18s ease;
}

.timeline__item--now .timeline__dot {
  background: var(--orange);
  border-color: var(--orange);
  box-shadow: 0 0 0 5px var(--orange-100);
}

.timeline__item:hover .timeline__dot,
.timeline__item:focus-within .timeline__dot {
  box-shadow: 0 0 0 5px var(--blue-100);
}
.timeline__item--now:hover .timeline__dot,
.timeline__item--now:focus-within .timeline__dot {
  box-shadow: 0 0 0 5px var(--orange-100);
}

.timeline__time {
  font-family: var(--font-mono);
  font-variant-numeric: tabular-nums;
  font-weight: 700;
  color: var(--blue-600);
  font-size: .9375rem;
}

.timeline__title { font-size: 1.0625rem; margin: 2px 0 4px; }
.timeline__text { font-size: .9375rem; color: var(--muted); max-width: none; }

.compare-row { margin-bottom: 18px; }
.compare-row__label {
  display: flex;
  flex-wrap: wrap;
  justify-content: space-between;
  gap: 8px;
  font-size: .875rem;
  font-weight: 700;
  color: var(--navy-800);
  margin-bottom: 8px;
}
.compare-row__label .num { font-weight: 700; }

.compare-bar {
  display: flex;
  height: 14px;
  border-radius: var(--r-pill);
  background: var(--blue-100);
  overflow: hidden;
}

.compare-bar__fill {
  display: block;
  height: 100%;
  width: 0;
  border-radius: inherit;
  background: linear-gradient(90deg, var(--blue-600), var(--orange));
  transition: width .22s ease;
}
.compare-bar--orange .compare-bar__fill {
  background: linear-gradient(90deg, var(--orange), var(--amber));
}

/* ---------- 7. 按钮 / 面包屑 / 图片容器 ---------- */
.btn {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  gap: 8px;
  padding: 12px 22px;
  border: 2px solid transparent;
  border-radius: var(--r-pill);
  font-size: .9375rem;
  font-weight: 700;
  letter-spacing: .01em;
  text-align: center;
  transition: transform .18s ease, box-shadow .18s ease,
    background-color .18s ease, color .18s ease, border-color .18s ease;
}

.btn--primary {
  background: var(--orange);
  color: var(--navy-900);
  box-shadow: 0 12px 24px -16px rgba(255, 106, 26, .95);
}
.btn--primary:hover {
  background: var(--orange-hover);
  transform: translateY(-2px);
  box-shadow: 0 18px 30px -16px rgba(255, 106, 26, .95);
}

.btn--navy {
  background: var(--navy-900);
  color: #fff;
}
.btn--navy:hover {
  background: var(--navy-800);
  transform: translateY(-2px);
}

.btn--ghost {
  background: transparent;
  border-color: var(--line);
  color: var(--navy-900);
}
.btn--ghost:hover {
  border-color: var(--blue-600);
  color: var(--blue-600);
  transform: translateY(-2px);
}

.btn--light {
  background: rgba(255, 255, 255, .12);
  border-color: rgba(255, 255, 255, .24);
  color: #fff;
}
.btn--light:hover { background: rgba(255, 255, 255, .2); }

.btn--sm { padding: 9px 17px; font-size: .875rem; }

.btn-row {
  display: flex;
  flex-wrap: wrap;
  align-items: center;
  gap: 12px;
}

.breadcrumb { margin-bottom: 20px; }
.breadcrumb__list {
  display: flex;
  flex-wrap: wrap;
  align-items: center;
  gap: 6px;
  font-size: .875rem;
  color: var(--muted);
}
.breadcrumb__item { display: inline-flex; align-items: center; gap: 6px; }
.breadcrumb__item + .breadcrumb__item::before {
  content: "/";
  color: var(--line);
}
.breadcrumb__item a { transition: color .18s ease; }
.breadcrumb__item a:hover { color: var(--blue-600); }

.media-frame {
  position: relative;
  overflow: hidden;
  isolation: isolate;
  aspect-ratio: 16 / 9;
  border-radius: var(--r-lg);
  background:
    radial-gradient(120% 120% at 12% 8%, rgba(31, 99, 196, .55) 0%, rgba(10, 26, 49, 0) 62%),
    linear-gradient(150deg, var(--navy-900) 0%, var(--navy-800) 62%, #0E2A52 100%);
}
.media-frame--wide { aspect-ratio: 21 / 9; }
.media-frame--square { aspect-ratio: 1 / 1; }
.media-frame--tall { aspect-ratio: 4 / 5; }

.media-frame img {
  width: 100%;
  height: 100%;
  object-fit: cover;
}

.media-frame__caption {
  position: absolute;
  left: 0;
  right: 0;
  bottom: 0;
  padding: 16px 18px;
  font-size: .8125rem;
  letter-spacing: .03em;
  color: #fff;
  background: linear-gradient(transparent, rgba(10, 26, 49, .88));
}

.media-frame__label {
  position: absolute;
  top: 14px;
  left: 14px;
}

/* ---------- 8. 页头 ---------- */
.skip-link {
  position: fixed;
  top: 10px;
  left: 50%;
  z-index: 200;
  padding: 10px 20px;
  border-radius: var(--r-pill);
  background: var(--orange);
  color: var(--navy-900);
  font-weight: 700;
  transform: translate(-50%, -180%);
  transition: transform .2s ease;
}
.skip-link:focus { transform: translate(-50%, 0); }

.site-header {
  position: sticky;
  top: 0;
  z-index: 80;
  padding: 14px clamp(12px, 3vw, 28px) 0;
  transition: padding .22s ease;
}
.site-header.is-condensed { padding-top: 8px; }

.scroll-progress {
  position: absolute;
  top: 0;
  left: 0;
  right: 0;
  height: 3px;
  background: transparent;
  pointer-events: none;
}
.scroll-progress__bar {
  display: block;
  height: 100%;
  width: 100%;
  transform: scaleX(0);
  transform-origin: 0 50%;
  background: linear-gradient(90deg, var(--orange), var(--amber));
}

.header-shell {
  position: relative;
  width: min(1240px, 100%);
  margin-inline: auto;
  display: grid;
  grid-template-columns: auto minmax(0, 1fr) auto;
  align-items: center;
  gap: clamp(10px, 2vw, 22px);
  padding: 10px 10px 10px 14px;
  border-radius: var(--r-pill);
  background: rgba(10, 26, 49, .92);
  border: 1px solid rgba(255, 255, 255, .1);
  box-shadow: var(--shadow-bar);
  -webkit-backdrop-filter: blur(10px) saturate(140%);
  backdrop-filter: blur(10px) saturate(140%);
  transition: padding .22s ease, background-color .22s ease;
}
.site-header.is-condensed .header-shell {
  padding: 6px 8px 6px 10px;
  background: rgba(10, 26, 49, .97);
}

.brand {
  display: inline-flex;
  align-items: center;
  gap: 11px;
  padding: 6px 14px 6px 6px;
  border-radius: var(--r-pill);
  color: #fff;
  transition: background-color .18s ease;
}
.brand:hover { background: rgba(255, 255, 255, .08); }

.brand-mark {
  position: relative;
  flex: none;
  width: 36px;
  height: 36px;
  border-radius: 13px;
  background: linear-gradient(140deg, #FF8F45, var(--orange));
  box-shadow: inset 0 -6px 12px rgba(10, 26, 49, .18);
}
.brand-mark::before,
.brand-mark::after {
  content: "";
  position: absolute;
  left: 9px;
  height: 3px;
  border-radius: 3px;
  background: var(--navy-900);
  transform: skewX(-24deg);
}
.brand-mark::before { top: 13px; width: 18px; }
.brand-mark::after { top: 20px; left: 13px; width: 14px; background: rgba(10, 26, 49, .6); }

.brand-text {
  display: flex;
  flex-direction: column;
  line-height: 1.15;
}

.brand-name {
  font-size: 1rem;
  font-weight: 800;
  letter-spacing: -.01em;
  white-space: nowrap;
}

.brand-sub {
  font-size: .75rem;
  letter-spacing: .06em;
  color: rgba(255, 255, 255, .6);
  max-height: 22px;
  overflow: hidden;
  transition: opacity .2s ease, max-height .2s ease;
}
.site-header.is-condensed .brand-sub {
  opacity: 0;
  max-height: 0;
}

.nav-capsule {
  justify-self: center;
  padding: 5px;
  border-radius: var(--r-pill);
  background: rgba(255, 255, 255, .07);
  border: 1px solid rgba(255, 255, 255, .1);
}

.nav-list {
  display: flex;
  align-items: center;
  gap: 2px;
}

.nav-list a {
  display: block;
  padding: 9px 15px;
  border-radius: var(--r-pill);
  font-size: .9375rem;
  font-weight: 600;
  color: rgba(255, 255, 255, .78);
  white-space: nowrap;
  transition: background-color .18s ease, color .18s ease;
}
.nav-list a:hover { color: #fff; background: rgba(255, 255, 255, .12); }
.nav-list a[aria-current="page"] {
  background: var(--orange);
  color: var(--navy-900);
  font-weight: 700;
}

.header-actions {
  justify-self: end;
  display: flex;
  align-items: center;
  gap: 8px;
}

.nav-toggle {
  display: none;
  align-items: center;
  gap: 8px;
  padding: 9px 15px;
  border-radius: var(--r-pill);
  border: 1px solid rgba(255, 255, 255, .24);
  color: #fff;
  font-size: .875rem;
  font-weight: 700;
  transition: background-color .18s ease, border-color .18s ease;
}
.nav-toggle:hover { background: rgba(255, 255, 255, .14); }

.nav-toggle-bars {
  display: grid;
  gap: 4px;
  width: 18px;
}
.nav-toggle-bars span {
  display: block;
  height: 2px;
  border-radius: 2px;
  background: currentColor;
  transition: transform .2s ease, opacity .2s ease;
}
.nav-toggle[aria-expanded="true"] .nav-toggle-bars span:nth-child(1) {
  transform: translateY(6px) rotate(45deg);
}
.nav-toggle[aria-expanded="true"] .nav-toggle-bars span:nth-child(2) { opacity: 0; }
.nav-toggle[aria-expanded="true"] .nav-toggle-bars span:nth-child(3) {
  transform: translateY(-6px) rotate(-45deg);
}

/* ---------- 9. 页脚 ---------- */
.site-footer {
  position: relative;
  margin-top: clamp(48px, 8vw, 96px);
  background: var(--navy-900);
  color: rgba(255, 255, 255, .74);
}
.site-footer::before {
  content: "";
  position: absolute;
  top: 0;
  left: 0;
  right: 0;
  height: 3px;
  background: linear-gradient(90deg, var(--orange) 0%, rgba(255, 106, 26, .25) 42%, rgba(255, 106, 26, 0) 100%);
}

.footer-shell {
  width: min(var(--wrap), 100%);
  margin-inline: auto;
  padding: clamp(40px, 6vw, 72px) var(--gutter) 0;
}

.footer-grid {
  display: grid;
  grid-template-columns: 1.5fr 1fr 1fr 1.4fr;
  gap: clamp(24px, 4vw, 48px);
  padding-bottom: clamp(30px, 4vw, 46px);
}

.footer-col { min-width: 0; }

.footer-brand {
  font-size: 1.25rem;
  font-weight: 800;
  letter-spacing: -.01em;
  color: #fff;
  margin-bottom: 10px;
}

.footer-tagline {
  font-size: .9375rem;
  line-height: 1.7;
  max-width: 32ch;
  margin-bottom: 12px;
}

.footer-note {
  font-size: .8125rem;
  color: rgba(255, 255, 255, .52);
  max-width: 34ch;
  margin-bottom: 16px;
}

.footer-cta { margin-top: 4px; }

.footer-heading {
  font-size: .8125rem;
  font-weight: 700;
  letter-spacing: .12em;
  text-transform: uppercase;
  color: #fff;
  margin-bottom: 14px;
}

.footer-list li { margin-bottom: 10px; }
.footer-list a {
  font-size: .9375rem;
  color: rgba(255, 255, 255, .74);
  border-bottom: 2px solid transparent;
  transition: color .18s ease, border-color .18s ease;
}
.footer-list a:hover {
  color: #fff;
  border-color: var(--orange);
}

.footer-contact li {
  display: flex;
  gap: 10px;
  align-items: flex-start;
  margin-bottom: 12px;
  font-size: .9375rem;
}

.footer-contact__key {
  flex: none;
  width: 40px;
  padding-top: 2px;
  font-size: .8125rem;
  letter-spacing: .08em;
  color: rgba(255, 255, 255, .5);
}

.footer-contact__value {
  min-width: 0;
  word-break: break-word;
  max-width: none;
}
.footer-contact__value.mono {
  font-family: var(--font-mono);
  font-variant-numeric: tabular-nums;
  color: #fff;
}

.footer-col--contact .footer-note { margin-top: 6px; margin-bottom: 0; }

.footer-divider {
  height: 2px;
  border-radius: 2px;
  background: linear-gradient(90deg, var(--orange) 0 140px, rgba(255, 255, 255, .12) 140px 100%);
}

.footer-bottom {
  display: flex;
  flex-wrap: wrap;
  justify-content: space-between;
  gap: 8px 24px;
  padding: 20px 0 34px;
  font-size: .8125rem;
  color: rgba(255, 255, 255, .55);
}

.footer-legal {
  font-family: var(--font-mono);
  font-variant-numeric: tabular-nums;
  letter-spacing: .02em;
}

.footer-copy { max-width: none; }
.footer-copy [data-year] { font-family: var(--font-mono); color: rgba(255, 255, 255, .78); }

/* ---------- 10. 动效 · 显现 · 无障碍 ---------- */
:focus-visible {
  outline: 2px solid var(--orange);
  outline-offset: 3px;
}

#main-content { display: block; outline: none; }

.has-reveal [data-reveal] {
  opacity: 0;
  transform: translateY(16px);
  transition: opacity .5s ease, transform .5s ease;
}
.has-reveal [data-reveal].is-revealed {
  opacity: 1;
  transform: none;
}

/* ---------- 响应式：平板 ---------- */
@media (max-width: 1024px) {
  .footer-grid { grid-template-columns: 1.4fr 1fr 1fr; }
  .footer-col--contact { grid-column: 1 / -1; }
}

@media (max-width: 960px) {
  .grid--3 { grid-template-columns: repeat(2, minmax(0, 1fr)); }
  .grid--split { grid-template-columns: minmax(0, 1fr); }
  .brand-sub { display: none; }
  .nav-list a { padding: 9px 12px; font-size: .875rem; }
}

/* ---------- 响应式：移动 + 折叠导航 ---------- */
@media (max-width: 900px) {
  .header-shell { grid-template-columns: minmax(0, 1fr) auto; }

  .nav-capsule {
    position: absolute;
    top: calc(100% + 10px);
    left: 0;
    right: 0;
    z-index: 5;
    justify-self: stretch;
    padding: 12px;
    border-radius: var(--r-lg);
    background: rgba(10, 26, 49, .98);
    border: 1px solid rgba(255, 255, 255, .14);
    box-shadow: 0 30px 60px -30px rgba(10, 26, 49, .95);
    visibility: hidden;
    opacity: 0;
    transform: translateY(-8px);
    pointer-events: none;
    transition: opacity .18s ease, transform .18s ease, visibility .18s linear;
  }

  .nav-capsule[data-open="true"] {
    visibility: visible;
    opacity: 1;
    transform: none;
    pointer-events: auto;
  }

  .nav-list { flex-direction: column; align-items: stretch; gap: 4px; }

  .nav-list a {
    padding: 12px 16px;
    border-radius: var(--r-md);
    font-size: 1rem;
    color: rgba(255, 255, 255, .82);
  }
  .nav-list a[aria-current="page"] {
    background: var(--orange);
    color: var(--navy-900);
  }

  .nav-toggle { display: inline-flex; }
}

@media (max-width: 680px) {
  body { font-size: 16px; }

  .grid--2,
  .grid--3 { grid-template-columns: minmax(0, 1fr); }

  .chapter-head { grid-template-columns: minmax(0, 1fr); gap: 8px; }
  .chapter-index { font-size: 3rem; }

  .footer-grid { grid-template-columns: minmax(0, 1fr); gap: 28px; }
  .footer-col--contact { grid-column: auto; }
  .footer-tagline,
  .footer-note { max-width: 42ch; }
}

@media (max-width: 560px) {
  .nav-toggle-label { display: none; }
  .nav-toggle { padding: 9px 12px; }
  .header-cta { padding: 8px 13px; font-size: .8125rem; }
  .brand-name { font-size: .9375rem; }
  .btn { padding: 11px 18px; }
}

/* ---------- 减弱动效 ---------- */
@media (prefers-reduced-motion: reduce) {
  html { scroll-behavior: auto; }

  *,
  *::before,
  *::after {
    animation-duration: .001ms !important;
    animation-iteration-count: 1 !important;
    transition-duration: .001ms !important;
    transition-delay: 0ms !important;
  }

  .card:hover,
  .card:focus-within,
  .folder-card:hover,
  .folder-card:focus-within,
  .datacard:hover,
  .datacard:focus-within,
  .btn:hover { transform: none; }

  .has-reveal [data-reveal] {
    opacity: 1;
    transform: none;
  }
}

@media print {
  .site-header,
  .site-footer,
  .scroll-progress { display: none; }
}