:root {
  --color-surface: #fefefe;
  --color-surface-alt: #f5f5f6;
  --color-surface-deep: #e8e8ea;
  --color-ink: #454a54;
  --color-ink-soft: #69707d;
  --color-ink-muted: #757d8a;
  --color-line: #dddedf;
  --color-primary: #3b6cc4;
  --color-primary-ink: #ffffff;
  --color-primary-soft: #e3eaf6;
  --color-accent: #5732cd;
  --color-accent-ink: #ffffff;
  --color-highlight: #e0d9f5;
  --color-focus: #5025da;
  --color-contrast-surface: #1a202b;
  --color-contrast-ink: #e4e5e7;
  --color-contrast-line: #464b54;
  --color-contrast-accent: #9078de;
  --overlay-scrim: linear-gradient(180deg, rgba(26, 32, 43, 0.35) 0%, rgba(26, 32, 43, 0.72) 55%, rgba(26, 32, 43, 0.92) 100%);
  --font-heading: "PingFang SC", "HarmonyOS Sans SC", "Microsoft YaHei", "Source Han Sans SC", sans-serif;
  --font-body: "PingFang SC", "HarmonyOS Sans SC", "Microsoft YaHei", "Source Han Sans SC", sans-serif;
  --font-mono: ui-monospace, SFMono-Regular, Menlo, Consolas, monospace;
  --text-xs: 12.9px;
  --text-sm: 15.5px;
  --text-base: 17px;
  --text-lg: 20.4px;
  --text-xl: 24.5px;
  --text-2xl: 29.4px;
  --text-3xl: 35.3px;
  --text-4xl: 42.3px;
  --text-display: clamp(45px, 9.3vw, 119px);
  --text-figure: clamp(38px, 6.7vw, 86px);
  --weight-heading: 680;
  --weight-body: 400;
  --leading-body: 1.78;
  --leading-heading: 1.22;
  --tracking-heading: -0.007em;
  --radius-sm: 14px;
  --radius-md: 18px;
  --radius-lg: 23px;
  --radius-pill: 999px;
  --border-thin: 1px;
  --border-thick: 1px;
  --shadow-1: 0 6px 18px rgba(69, 74, 84, 0.08);
  --shadow-2: 0 18px 44px rgba(69, 74, 84, 0.14);
  --space-1: 8px;
  --space-2: 16px;
  --space-3: 24px;
  --space-4: 32px;
  --space-6: 48px;
  --space-8: 64px;
  --container: 1220px;
  --measure: 72ch;
  --gutter: 32px;
  --section-y: 94px;
  --section-y-lg: 132px;
}

/* ============================================================
   01. 重置与基础排版
   ============================================================ */
*,
*::before,
*::after { box-sizing: border-box; }

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

body {
  margin: 0;
  font-family: var(--font-body);
  font-size: var(--text-base);
  font-weight: var(--weight-body);
  line-height: var(--leading-body);
  color: var(--color-ink);
  background-color: var(--color-surface);
  -webkit-font-smoothing: antialiased;
  -moz-osx-font-smoothing: grayscale;
}

h1, h2, h3, h4, h5, h6 {
  margin: 0;
  font-family: var(--font-heading);
  font-weight: var(--weight-heading);
  line-height: var(--leading-heading);
  letter-spacing: var(--tracking-heading);
  color: var(--color-ink);
}

h1 { font-size: var(--text-3xl); }
h2 { font-size: var(--text-2xl); }
h3 { font-size: var(--text-xl); }
h4 { font-size: var(--text-lg); }

p {
  margin: 0 0 var(--space-3);
  word-break: break-word;
}
p:last-child { margin-bottom: 0; }

ul, ol { margin: 0; padding: 0; list-style: none; }
figure { margin: 0; }
img, svg, video { display: block; max-width: 100%; height: auto; }
button { font: inherit; color: inherit; }
input, select, textarea { font: inherit; color: inherit; }

a {
  color: color-mix(in srgb, var(--color-primary) 88%, var(--color-ink));
  text-decoration: none;
  text-underline-offset: 3px;
}
a:hover { text-decoration: underline; }

:focus-visible {
  outline: 2px solid var(--color-focus);
  outline-offset: 3px;
}

[id] { scroll-margin-top: 132px; }

/* ============================================================
   02. 布局工具
   ============================================================ */
.container {
  width: 100%;
  max-width: var(--container);
  margin-inline: auto;
  padding-inline: clamp(20px, 4vw, var(--gutter));
}

.grid { display: grid; gap: var(--space-4); }

.grid-12 {
  display: grid;
  grid-template-columns: repeat(12, minmax(0, 1fr));
  gap: var(--gutter);
}

.stack > * + * { margin-top: var(--space-3); }
.stack-lg > * + * { margin-top: var(--space-6); }

.section { padding-block: var(--section-y); }
.section--lg { padding-block: var(--section-y-lg); }

@media (max-width: 1024px) {
  .grid-12 {
    grid-template-columns: repeat(6, minmax(0, 1fr));
    gap: var(--space-3);
  }
}

@media (max-width: 640px) {
  .grid-12 { grid-template-columns: repeat(2, minmax(0, 1fr)); }
}

/* ============================================================
   03. 玻璃层叠：彩色底层 + 半透明面板
   ============================================================ */
.color-bed {
  position: relative;
  isolation: isolate;
  overflow: clip;
  border-radius: var(--radius-lg);
  padding: clamp(24px, 4.2vw, 60px);
  background-color: color-mix(in srgb, var(--color-primary) 30%, var(--color-surface));
  background-image:
    radial-gradient(120% 100% at 0% 0%,
      color-mix(in srgb, var(--color-primary) 88%, transparent) 0%,
      transparent 58%),
    radial-gradient(100% 90% at 100% 100%,
      color-mix(in srgb, var(--color-accent) 78%, transparent) 0%,
      transparent 62%);
}

.color-bed--accent {
  background-color: color-mix(in srgb, var(--color-accent) 28%, var(--color-surface));
  background-image:
    radial-gradient(110% 95% at 100% 0%,
      color-mix(in srgb, var(--color-accent) 86%, transparent) 0%,
      transparent 60%),
    radial-gradient(100% 90% at 0% 100%,
      color-mix(in srgb, var(--color-primary) 72%, transparent) 0%,
      transparent 62%);
}

.glass,
.panel {
  position: relative;
  padding: clamp(20px, 2.6vw, var(--space-4));
  border-radius: var(--radius-lg);
  border: var(--border-thin) solid color-mix(in srgb, var(--color-highlight) 92%, transparent);
  background-color: color-mix(in srgb, var(--color-surface) 72%, transparent);
  -webkit-backdrop-filter: blur(16px) saturate(150%);
  backdrop-filter: blur(16px) saturate(150%);
  box-shadow: var(--shadow-1);
  transition: box-shadow 0.2s ease, border-color 0.2s ease;
}

.glass:hover,
.panel:hover {
  box-shadow: var(--shadow-2);
  border-color: var(--color-highlight);
}

.glass--tight { padding: var(--space-3); }
.glass--flush { padding: 0; overflow: hidden; }

/* ============================================================
   04. 头部：双层信息导航
   ============================================================ */
.site-header {
  position: sticky;
  top: 0;
  z-index: 90;
  isolation: isolate;
  background-color: color-mix(in srgb, var(--color-surface) 82%, transparent);
  -webkit-backdrop-filter: blur(20px) saturate(160%);
  backdrop-filter: blur(20px) saturate(160%);
  border-bottom: var(--border-thin) solid color-mix(in srgb, var(--color-highlight) 95%, transparent);
  box-shadow: var(--shadow-1);
}

.site-header::before {
  content: "";
  position: absolute;
  inset: 0;
  z-index: -1;
  pointer-events: none;
  background-image:
    linear-gradient(104deg,
      color-mix(in srgb, var(--color-primary) 30%, transparent) 0%,
      transparent 46%),
    linear-gradient(256deg,
      color-mix(in srgb, var(--color-accent) 26%, transparent) 0%,
      transparent 44%);
}

.header-inner {
  position: relative;
  padding-block: clamp(10px, 1.6vw, var(--space-2)) 0;
}

.header-top {
  display: flex;
  flex-wrap: wrap;
  align-items: center;
  gap: var(--space-1) var(--space-4);
  justify-content: space-between;
}

.header-line {
  margin: 0;
  flex: 1 1 auto;
  font-size: var(--text-sm);
  color: var(--color-ink-soft);
}

.header-status {
  margin: 0;
  display: inline-flex;
  align-items: center;
  font-size: var(--text-xs);
  letter-spacing: 0.04em;
  color: var(--color-ink-muted);
  font-variant-numeric: tabular-nums;
}

.pulse {
  display: inline-block;
  width: 7px;
  height: 7px;
  margin-right: 8px;
  border-radius: 50%;
  background-color: var(--color-accent);
  box-shadow: 0 0 0 4px color-mix(in srgb, var(--color-accent) 18%, transparent);
  flex: none;
}

/* 品牌 */
.brand {
  display: inline-flex;
  align-items: center;
  gap: var(--space-2);
  text-decoration: none;
}
.brand:hover { text-decoration: none; }

.brand-mark {
  display: grid;
  place-items: center;
  flex: none;
  width: 40px;
  height: 40px;
  border-radius: var(--radius-sm);
  background-color: var(--color-primary);
  color: var(--color-primary-ink);
  font-family: var(--font-heading);
  font-weight: var(--weight-heading);
  font-size: var(--text-lg);
  line-height: 1;
  transition: width 0.2s ease, height 0.2s ease, font-size 0.2s ease;
}

.brand-text {
  display: flex;
  flex-direction: column;
  gap: 2px;
  line-height: 1.14;
}

.brand-name {
  font-family: var(--font-heading);
  font-weight: var(--weight-heading);
  font-size: var(--text-lg);
  letter-spacing: -0.01em;
  color: var(--color-ink);
}

.brand-sub {
  font-family: var(--font-mono);
  font-size: var(--text-xs);
  letter-spacing: 0.16em;
  color: var(--color-ink-muted);
}

/* 下层：栏目条 */
.header-bottom {
  position: relative;
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: var(--space-3);
  margin-top: clamp(8px, 1.2vw, var(--space-2));
  padding-block: 6px;
  border-top: var(--border-thin) solid color-mix(in srgb, var(--color-line) 85%, transparent);
}

.primary-nav { min-width: 0; }

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

.nav-list a {
  display: block;
  padding: 9px 14px;
  border-radius: var(--radius-pill);
  border: var(--border-thin) solid transparent;
  font-size: var(--text-sm);
  line-height: 1.3;
  color: var(--color-ink-soft);
  transition: color 0.18s ease, background-color 0.18s ease, border-color 0.18s ease;
}

.nav-list a:hover {
  text-decoration: none;
  color: var(--color-ink);
  background-color: color-mix(in srgb, var(--color-primary-soft) 78%, transparent);
  border-color: color-mix(in srgb, var(--color-highlight) 90%, transparent);
}

.nav-list a[aria-current="page"] {
  color: var(--color-accent-ink);
  background-color: var(--color-accent);
  border-color: color-mix(in srgb, var(--color-accent) 70%, transparent);
  box-shadow: var(--shadow-1);
}

.nav-list a[aria-current="page"]:hover {
  color: var(--color-accent-ink);
  background-color: color-mix(in srgb, var(--color-accent) 88%, var(--color-primary));
}

/* 移动导航按钮 */
.nav-toggle {
  display: none;
  align-items: center;
  gap: 10px;
  padding: 10px 16px;
  border-radius: var(--radius-pill);
  border: var(--border-thin) solid color-mix(in srgb, var(--color-line) 92%, transparent);
  background-color: color-mix(in srgb, var(--color-surface) 70%, transparent);
  color: var(--color-ink);
  font-size: var(--text-sm);
  cursor: pointer;
  transition: border-color 0.18s ease, background-color 0.18s ease;
}

.nav-toggle:hover {
  border-color: var(--color-primary);
  background-color: color-mix(in srgb, var(--color-primary-soft) 70%, transparent);
}

.nav-toggle-bars {
  position: relative;
  display: block;
  width: 16px;
  height: 10px;
  flex: none;
}

.nav-toggle-bars::before,
.nav-toggle-bars::after {
  content: "";
  position: absolute;
  left: 0;
  right: 0;
  height: 2px;
  border-radius: 2px;
  background-color: currentColor;
  transition: transform 0.2s ease, top 0.2s ease, bottom 0.2s ease;
}

.nav-toggle-bars::before { top: 0; }
.nav-toggle-bars::after { bottom: 0; }

[aria-expanded="true"] .nav-toggle-bars::before {
  top: 4px;
  transform: rotate(45deg);
}
[aria-expanded="true"] .nav-toggle-bars::after {
  bottom: 4px;
  transform: rotate(-45deg);
}

/* 滚动进度条 */
.header-progress {
  position: absolute;
  left: 0;
  right: 0;
  bottom: 0;
  display: block;
  height: 2px;
  background-color: var(--color-accent);
  transform: scaleX(var(--progress, 0));
  transform-origin: left center;
  pointer-events: none;
}

/* 滚动后收窄为单层 */
.site-header.is-condensed .header-line,
.site-header.is-condensed .header-status { display: none; }

.site-header.is-condensed .brand-mark {
  width: 32px;
  height: 32px;
  font-size: var(--text-base);
}

.site-header.is-condensed .header-bottom { margin-top: 0; }

/* 头部响应式 */
@media (max-width: 900px) {
  .header-top {
    flex-direction: column;
    align-items: flex-start;
    gap: 6px;
  }
  .header-line,
  .header-status { font-size: var(--text-xs); }
  .brand-name { font-size: var(--text-base); }

  .header-bottom { padding-block: 8px; }

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

  .primary-nav {
    position: absolute;
    top: 100%;
    left: 0;
    right: 0;
    z-index: 20;
    margin-top: 6px;
    padding: var(--space-2);
    border-radius: var(--radius-md);
    border: var(--border-thin) solid color-mix(in srgb, var(--color-highlight) 95%, transparent);
    background-color: color-mix(in srgb, var(--color-surface) 96%, transparent);
    -webkit-backdrop-filter: blur(20px) saturate(150%);
    backdrop-filter: blur(20px) saturate(150%);
    box-shadow: var(--shadow-2);
    opacity: 0;
    visibility: hidden;
    transform: translateY(-8px);
    transition: opacity 0.18s ease, transform 0.18s ease, visibility 0.18s linear;
  }

  .primary-nav[data-open] {
    opacity: 1;
    visibility: visible;
    transform: none;
  }

  .nav-list { flex-direction: column; align-items: stretch; gap: 2px; }
  .nav-list a { padding: 12px 14px; border-radius: var(--radius-sm); }
}

/* ============================================================
   05. 阶梯式页脚（暗场）
   ============================================================ */
.site-footer {
  margin-top: var(--section-y-lg);
  padding-block: var(--section-y) var(--space-6);
  background-color: var(--color-contrast-surface);
  color: var(--color-contrast-ink);
}

.site-footer a {
  color: color-mix(in srgb, var(--color-contrast-ink) 86%, transparent);
}

.site-footer a:hover {
  color: var(--color-contrast-ink);
}

.site-footer .brand-mark {
  background-color: var(--color-contrast-accent);
  color: var(--color-contrast-surface);
}

.footer-top {
  display: grid;
  grid-template-columns: minmax(220px, 1fr) minmax(0, 2.2fr);
  gap: var(--space-6) var(--space-8);
  padding-bottom: var(--space-6);
  border-bottom: var(--border-thin) solid var(--color-contrast-line);
}

.footer-brand { display: grid; gap: var(--space-1); align-content: start; }

.footer-brand-name {
  margin: 0;
  font-family: var(--font-heading);
  font-weight: var(--weight-heading);
  font-size: var(--text-lg);
  color: var(--color-contrast-ink);
}

.footer-brand-note {
  margin: 0;
  font-size: var(--text-sm);
  color: color-mix(in srgb, var(--color-contrast-ink) 62%, transparent);
}

.footer-index {
  display: grid;
  grid-template-columns: repeat(3, minmax(0, 1fr));
  gap: var(--space-4);
}

.footer-col ul { display: grid; gap: 10px; }

.footer-col-title {
  margin: 0 0 var(--space-2);
  font-family: var(--font-mono);
  font-size: var(--text-xs);
  font-weight: var(--weight-heading);
  letter-spacing: 0.18em;
  color: var(--color-contrast-accent);
}

.footer-col a {
  font-size: var(--text-sm);
  line-height: 1.5;
}

.footer-fix {
  display: grid;
  gap: var(--space-2);
  padding-block: var(--space-6);
  border-bottom: var(--border-thin) solid var(--color-contrast-line);
}

.footer-fix-title {
  margin: 0;
  font-family: var(--font-mono);
  font-size: var(--text-xs);
  letter-spacing: 0.18em;
  color: var(--color-contrast-accent);
}

.footer-fix p {
  max-width: var(--measure);
  font-size: var(--text-sm);
  color: color-mix(in srgb, var(--color-contrast-ink) 74%, transparent);
}

.footer-legal {
  display: flex;
  flex-wrap: wrap;
  gap: var(--space-1) var(--space-4);
  padding-top: var(--space-4);
}

.footer-legal-item {
  margin: 0;
  font-size: var(--text-xs);
  letter-spacing: 0.01em;
  color: color-mix(in srgb, var(--color-contrast-ink) 58%, transparent);
  font-variant-numeric: tabular-nums;
}

@media (max-width: 900px) {
  .footer-top { grid-template-columns: minmax(0, 1fr); gap: var(--space-6); }
  .footer-index { grid-template-columns: repeat(2, minmax(0, 1fr)); }
}

@media (max-width: 560px) {
  .footer-index { grid-template-columns: minmax(0, 1fr); }
  .site-footer { padding-block: var(--section-y) var(--space-4); }
}

/* ============================================================
   06. 通用按钮
   ============================================================ */
.btn {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  gap: 8px;
  padding: 12px 22px;
  border-radius: var(--radius-pill);
  border: var(--border-thin) solid transparent;
  font-family: var(--font-heading);
  font-size: var(--text-sm);
  font-weight: var(--weight-heading);
  line-height: 1.3;
  letter-spacing: 0.01em;
  cursor: pointer;
  text-decoration: none;
  transition: background-color 0.18s ease, border-color 0.18s ease,
    color 0.18s ease, box-shadow 0.18s ease, transform 0.18s ease;
}

.btn:hover { text-decoration: none; }

.btn-primary {
  background-color: var(--color-primary);
  color: var(--color-primary-ink);
  box-shadow: var(--shadow-1);
}
.btn-primary:hover {
  background-color: color-mix(in srgb, var(--color-primary) 84%, var(--color-accent));
  box-shadow: var(--shadow-2);
  transform: translateY(-2px);
}

.btn-accent {
  background-color: var(--color-accent);
  color: var(--color-accent-ink);
  box-shadow: var(--shadow-1);
}
.btn-accent:hover {
  background-color: color-mix(in srgb, var(--color-accent) 84%, var(--color-primary));
  box-shadow: var(--shadow-2);
  transform: translateY(-2px);
}

.btn-ghost {
  background-color: color-mix(in srgb, var(--color-surface) 62%, transparent);
  color: var(--color-ink);
  border-color: color-mix(in srgb, var(--color-highlight) 95%, transparent);
  -webkit-backdrop-filter: blur(10px);
  backdrop-filter: blur(10px);
}
.btn-ghost:hover {
  background-color: color-mix(in srgb, var(--color-surface) 88%, transparent);
  border-color: var(--color-primary);
  transform: translateY(-2px);
}

/* ============================================================
   07. 面包屑与正文容器
   ============================================================ */
.breadcrumb {
  display: flex;
  flex-wrap: wrap;
  align-items: center;
  gap: 8px;
  font-size: var(--text-xs);
  color: var(--color-ink-muted);
}

.breadcrumb li {
  display: inline-flex;
  align-items: center;
  gap: 8px;
}

.breadcrumb li + li::before {
  content: "/";
  color: color-mix(in srgb, var(--color-ink-muted) 55%, transparent);
}

.breadcrumb a { color: var(--color-ink-soft); }
.breadcrumb [aria-current="page"] { color: var(--color-ink); }

.prose {
  max-width: var(--measure);
  font-size: var(--text-base);
  color: var(--color-ink);
}

.prose > :first-child { margin-top: 0; }
.prose h2 { margin-top: var(--space-6); font-size: var(--text-2xl); }
.prose h3 { margin-top: var(--space-4); font-size: var(--text-xl); }
.prose h4 { margin-top: var(--space-3); font-size: var(--text-lg); }
.prose p,
.prose ol { margin-top: var(--space-3); }

.prose ul {
  display: grid;
  gap: var(--space-1);
  margin-top: var(--space-3);
}
.prose ul > li {
  position: relative;
  padding-left: var(--space-3);
}
.prose ul > li::before {
  content: "";
  position: absolute;
  left: 0;
  top: 0.78em;
  width: 8px;
  height: 2px;
  background-color: var(--color-primary);
}
.prose ol {
  counter-reset: prose-ol;
  display: grid;
  gap: var(--space-1);
  padding-left: var(--space-3);
}
.prose ol > li {
  counter-increment: prose-ol;
  position: relative;
  padding-left: var(--space-2);
}
.prose ol > li::before {
  content: counter(prose-ol) ".";
  position: absolute;
  left: 0;
  font-family: var(--font-mono);
  font-size: var(--text-sm);
  color: var(--color-ink-muted);
}
.prose a { text-decoration: underline; }
.prose hr {
  height: 0;
  margin: var(--space-6) 0;
  border: 0;
  border-top: var(--border-thin) solid var(--color-line);
}
.prose strong { font-weight: var(--weight-heading); color: var(--color-ink); }

/* ============================================================
   08. 区段标题与强调机制
   ============================================================ */
.section-head {
  display: grid;
  gap: var(--space-2);
  align-content: start;
}

.section-index {
  display: block;
  font-family: var(--font-heading);
  font-weight: var(--weight-heading);
  font-size: var(--text-figure);
  line-height: 0.88;
  letter-spacing: -0.04em;
  font-variant-numeric: tabular-nums;
  color: color-mix(in srgb, var(--color-primary) 32%, transparent);
}

.section-kicker {
  margin: 0;
  font-family: var(--font-mono);
  font-size: var(--text-xs);
  letter-spacing: 0.2em;
  text-transform: uppercase;
  color: var(--color-ink-muted);
}

.section-title {
  margin: 0;
  font-size: var(--text-3xl);
}

.section-lede {
  margin: 0;
  max-width: var(--measure);
  font-size: var(--text-base);
  color: var(--color-ink-soft);
}

/* ============================================================
   09. 标签、数字与代码字
   ============================================================ */
.tag {
  display: inline-flex;
  align-items: center;
  gap: 6px;
  padding: 4px 10px;
  border-radius: var(--radius-pill);
  border: var(--border-thin) solid color-mix(in srgb, var(--color-line) 92%, transparent);
  background-color: color-mix(in srgb, var(--color-surface) 72%, transparent);
  font-size: var(--text-xs);
  line-height: 1.5;
  letter-spacing: 0.02em;
  color: var(--color-ink-soft);
  white-space: nowrap;
}

.tag--accent {
  border-color: color-mix(in srgb, var(--color-accent) 42%, transparent);
  background-color: color-mix(in srgb, var(--color-accent) 9%, transparent);
  color: color-mix(in srgb, var(--color-accent) 88%, var(--color-ink));
}

.tag--data {
  font-family: var(--font-mono);
  font-variant-numeric: tabular-nums;
}

.code-label {
  font-family: var(--font-mono);
  font-size: var(--text-xs);
  letter-spacing: 0.18em;
  text-transform: uppercase;
  color: var(--color-ink-muted);
}

.num {
  font-family: var(--font-mono);
  font-variant-numeric: tabular-nums;
  font-feature-settings: "tnum" 1;
}

/* ============================================================
   10. 时间轴与数据表底座
   ============================================================ */
.timeline {
  position: relative;
  display: grid;
  gap: var(--space-4);
  padding-left: var(--space-4);
}

.timeline::before {
  content: "";
  position: absolute;
  left: 3px;
  top: 6px;
  bottom: 6px;
  width: var(--border-thin);
  background-color: var(--color-line);
}

.timeline-item { position: relative; }

.timeline-item::before {
  content: "";
  position: absolute;
  left: calc(var(--space-4) * -1 + 0px);
  top: 8px;
  width: 7px;
  height: 7px;
  border-radius: 50%;
  background-color: var(--color-surface);
  border: 2px solid var(--color-primary);
  transition: border-color 0.18s ease, box-shadow 0.18s ease;
}

.timeline-item.is-current::before,
.timeline-item[aria-current="true"]::before {
  border-color: var(--color-accent);
  background-color: var(--color-accent);
  box-shadow: 0 0 0 4px color-mix(in srgb, var(--color-accent) 16%, transparent);
}

.data-table {
  width: 100%;
  border-collapse: collapse;
  font-variant-numeric: tabular-nums;
}

.data-table caption {
  padding-bottom: var(--space-2);
  text-align: left;
  font-family: var(--font-mono);
  font-size: var(--text-xs);
  letter-spacing: 0.14em;
  color: var(--color-ink-muted);
}

.data-table th,
.data-table td {
  padding: 12px var(--space-3);
  text-align: left;
  font-size: var(--text-sm);
  border-bottom: var(--border-thin) solid var(--color-line);
}

.data-table thead th {
  font-family: var(--font-heading);
  font-weight: var(--weight-heading);
  color: var(--color-ink);
  background-color: color-mix(in srgb, var(--color-primary-soft) 58%, transparent);
}

.data-table tbody tr:nth-child(even) {
  background-color: color-mix(in srgb, var(--color-surface-deep) 52%, transparent);
}

/* ============================================================
   11. 图片容器
   ============================================================ */
.media {
  position: relative;
  isolation: isolate;
  overflow: hidden;
  aspect-ratio: 16 / 9;
  border-radius: var(--radius-lg);
  border: var(--border-thin) solid color-mix(in srgb, var(--color-highlight) 85%, transparent);
  background-color: var(--color-surface-deep);
  box-shadow: var(--shadow-1);
}

.media img {
  width: 100%;
  height: 100%;
  object-fit: cover;
  filter: saturate(0.88) contrast(1.05);
}

.media-scrim {
  position: absolute;
  inset: 0;
  z-index: 2;
  background-image: var(--overlay-scrim);
  pointer-events: none;
}

.media-caption {
  position: absolute;
  left: 0;
  right: 0;
  bottom: 0;
  z-index: 3;
  padding: var(--space-3);
  font-size: var(--text-sm);
  line-height: 1.6;
  color: var(--color-contrast-ink);
}

.media--tall { aspect-ratio: 3 / 4; }
.media--square { aspect-ratio: 1 / 1; }
.media--wide { aspect-ratio: 21 / 9; }

/* ============================================================
   12. 无障碍
   ============================================================ */
.skip-link {
  position: fixed;
  left: var(--space-3);
  top: calc(var(--space-1) * -10);
  z-index: 200;
  padding: 12px 20px;
  border-radius: var(--radius-pill);
  background-color: var(--color-accent);
  color: var(--color-accent-ink);
  font-size: var(--text-sm);
  font-weight: var(--weight-heading);
  box-shadow: var(--shadow-2);
  transition: top 0.18s ease;
}

.skip-link:focus {
  top: var(--space-2);
  text-decoration: none;
}

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

/* ============================================================
   13. 降低动效
   ============================================================ */
@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;
  }

  .btn:hover,
  .btn-primary:hover,
  .btn-accent:hover,
  .btn-ghost:hover { transform: none; }

  .primary-nav {
    transition: none;
  }
}