:root {
  --color-surface: #fdfdfd;
  --color-surface-alt: #f4f4f4;
  --color-surface-deep: #e7e8e9;
  --color-ink: #464c53;
  --color-ink-soft: #687078;
  --color-ink-muted: #787f87;
  --color-line: #dcddde;
  --color-primary: #3476c1;
  --color-primary-ink: #ffffff;
  --color-primary-soft: #e1eaf5;
  --color-accent: #dc3823;
  --color-accent-ink: #ffffff;
  --color-highlight: #f7dad6;
  --color-focus: #db2b14;
  --color-contrast-surface: #10151b;
  --color-contrast-ink: #e4e5e7;
  --color-contrast-line: #3f4348;
  --color-contrast-accent: #e04c39;
  --overlay-scrim: linear-gradient(180deg, rgba(16, 21, 27, 0.35) 0%, rgba(16, 21, 27, 0.72) 55%, rgba(16, 21, 27, 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: 12.2px;
  --text-sm: 14.6px;
  --text-base: 16px;
  --text-lg: 19.2px;
  --text-xl: 23.0px;
  --text-2xl: 27.6px;
  --text-3xl: 33.2px;
  --text-4xl: 39.8px;
  --text-display: clamp(34px, 4.4vw, 56px);
  --text-figure: clamp(28px, 3.1vw, 40px);
  --weight-heading: 652;
  --weight-body: 400;
  --leading-body: 1.65;
  --leading-heading: 1.24;
  --tracking-heading: -0.005em;
  --radius-sm: 4px;
  --radius-md: 6px;
  --radius-lg: 7px;
  --radius-pill: 7px;
  --border-thin: 1px;
  --border-thick: 2px;
  --shadow-1: 0 1px 0 rgba(70, 76, 83, 0.12);
  --shadow-2: 0 2px 0 rgba(70, 76, 83, 0.18);
  --space-1: 8px;
  --space-2: 16px;
  --space-3: 24px;
  --space-4: 32px;
  --space-6: 48px;
  --space-8: 64px;
  --container: 1040px;
  --measure: 73ch;
  --gutter: 32px;
  --section-y: 72px;
  --section-y-lg: 101px;
}

/* ------------------------------------------------------------
   派生布局变量
   ------------------------------------------------------------ */
html {
  --rail-w: 226px;
  --rail-pad: 24px;
}

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

html {
  font-size: 100%;
  -webkit-text-size-adjust: 100%;
  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, p, figure, blockquote, dl, dd, pre { margin: 0; }
ul, ol { margin: 0; padding: 0; list-style: none; }
img, svg, video, canvas { display: block; max-width: 100%; height: auto; }
a { color: inherit; text-decoration: none; }
button { font: inherit; color: inherit; background: none; border: 0; padding: 0; cursor: pointer; }
table { border-collapse: collapse; border-spacing: 0; }
hr { border: 0; margin: 0; }
main { display: block; }

/* ------------------------------------------------------------
   中文排版基调
   ------------------------------------------------------------ */
h1, h2, h3, h4, h5, h6 {
  font-family: var(--font-heading);
  font-weight: var(--weight-heading);
  line-height: var(--leading-heading);
  letter-spacing: var(--tracking-heading);
  color: var(--color-ink);
  text-wrap: balance;
}
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 { max-width: var(--measure); }

strong, b { font-weight: 600; color: var(--color-ink); }

.mono,
code, kbd, samp {
  font-family: var(--font-mono);
  font-size: 0.94em;
  font-variant-numeric: tabular-nums;
  letter-spacing: 0.01em;
}

.display-lg {
  font-family: var(--font-heading);
  font-size: var(--text-display);
  font-weight: var(--weight-heading);
  line-height: var(--leading-heading);
  letter-spacing: -0.02em;
}

.figure-lg {
  font-family: var(--font-mono);
  font-size: var(--text-figure);
  font-weight: 600;
  line-height: 1.08;
  font-variant-numeric: tabular-nums;
  letter-spacing: -0.01em;
}

.prose { max-width: var(--measure); }
.prose > * + * { margin-top: var(--space-3); }

/* ------------------------------------------------------------
   焦点
   ------------------------------------------------------------ */
:focus-visible {
  outline: var(--border-thick) solid var(--color-focus);
  outline-offset: 2px;
  border-radius: 2px;
}

#main-content { scroll-margin-top: 96px; }

/* ------------------------------------------------------------
   跳转链接
   ------------------------------------------------------------ */
.skip-link {
  position: fixed;
  top: 0;
  left: 0;
  z-index: 200;
  padding: 10px var(--space-3);
  background-color: var(--color-primary);
  color: var(--color-primary-ink);
  font-size: var(--text-sm);
  border-radius: 0 0 var(--radius-sm) 0;
  transform: translateY(-130%);
  transition: transform 140ms ease;
}
.skip-link:focus { transform: translateY(0); }

/* ------------------------------------------------------------
   头部 · 框架式侧栏导航（移动端为顶栏）
   ------------------------------------------------------------ */
.site-header {
  position: sticky;
  top: 0;
  z-index: 60;
  background-color: var(--color-contrast-surface);
  color: var(--color-contrast-ink);
  border-bottom: var(--border-thin) solid var(--color-contrast-line);
}

.rail-inner {
  display: flex;
  flex-wrap: wrap;
  align-items: center;
}

/* 品牌 */
.brand {
  flex: 1 1 auto;
  min-width: 0;
  display: flex;
  align-items: center;
  gap: 12px;
  padding: var(--space-2) var(--rail-pad);
}
.brand__mark {
  position: relative;
  flex: 0 0 auto;
  width: 20px;
  height: 20px;
  border: var(--border-thin) solid var(--color-primary);
  border-radius: var(--radius-sm);
}
.brand__mark::before {
  content: "";
  position: absolute;
  left: 50%;
  top: 3px;
  bottom: 3px;
  width: 1px;
  background-color: var(--color-primary);
  transform: translateX(-50%);
}
.brand__mark::after {
  content: "";
  position: absolute;
  left: 50%;
  top: 50%;
  width: 5px;
  height: 5px;
  background-color: var(--color-primary);
  border-radius: 1px;
  transform: translate(-50%, -50%);
}
.brand__text { display: flex; flex-direction: column; min-width: 0; }
.brand__name {
  font-family: var(--font-heading);
  font-size: var(--text-lg);
  font-weight: var(--weight-heading);
  line-height: var(--leading-heading);
  letter-spacing: var(--tracking-heading);
  color: var(--color-contrast-ink);
}
.brand__line {
  font-family: var(--font-mono);
  font-size: var(--text-xs);
  line-height: 1.5;
  color: color-mix(in srgb, var(--color-contrast-ink) 58%, transparent);
}

/* 移动端导航按钮 */
.nav-toggle {
  flex: 0 0 auto;
  margin-right: var(--rail-pad);
  width: 40px;
  height: 40px;
  display: inline-flex;
  align-items: center;
  justify-content: center;
  border: var(--border-thin) solid var(--color-contrast-line);
  border-radius: var(--radius-sm);
  color: var(--color-contrast-ink);
  transition: border-color 140ms ease, background-color 140ms ease;
}
.nav-toggle:hover { border-color: var(--color-primary); background-color: color-mix(in srgb, var(--color-primary) 16%, transparent); }
.nav-toggle__bars { position: relative; display: block; width: 16px; height: 10px; }
.nav-toggle__bars::before,
.nav-toggle__bars::after {
  content: "";
  position: absolute;
  left: 0;
  right: 0;
  height: 1px;
  background-color: currentColor;
  transition: transform 140ms ease, top 140ms ease;
}
.nav-toggle__bars::before { top: 1px; }
.nav-toggle__bars::after { bottom: 1px; }
.site-header[data-open] .nav-toggle__bars::before { top: 50%; transform: translateY(-50%) rotate(45deg); }
.site-header[data-open] .nav-toggle__bars::after { bottom: auto; top: 50%; transform: translateY(-50%) rotate(-45deg); }

/* 导航 + 纵向轴线 */
.site-nav {
  flex: 1 1 100%;
  display: none;
  padding: var(--space-1) var(--rail-pad) var(--space-3);
}
.site-header[data-open] .site-nav { display: block; }

.site-nav__list { position: relative; }
.site-nav__list::before {
  content: "";
  position: absolute;
  left: 3px;
  top: 14px;
  bottom: 14px;
  border-left: var(--border-thin) dotted var(--color-contrast-line);
}
.site-nav__item { position: relative; }

.site-nav__link {
  position: relative;
  display: block;
  padding: 9px 0 9px 22px;
  border-left: var(--border-thick) solid transparent;
  font-size: var(--text-sm);
  color: color-mix(in srgb, var(--color-contrast-ink) 66%, transparent);
  transition: color 140ms ease, background-color 140ms ease, border-color 140ms ease;
}
.site-nav__link::before {
  content: "";
  position: absolute;
  left: -2px;
  top: 50%;
  width: 8px;
  height: 8px;
  margin-top: -4px;
  border-radius: 50%;
  background-color: var(--color-contrast-line);
  transition: background-color 140ms ease, border-radius 140ms ease, transform 140ms ease;
}
.site-nav__link:hover {
  color: var(--color-contrast-ink);
  background-color: color-mix(in srgb, var(--color-contrast-ink) 8%, transparent);
}
.site-nav__link:hover::before { background-color: var(--color-primary); }
.site-nav__link[aria-current="page"] {
  color: var(--color-contrast-ink);
  font-weight: 600;
  border-left-color: var(--color-primary);
  background-color: color-mix(in srgb, var(--color-primary) 18%, transparent);
}
.site-nav__link[aria-current="page"]::before {
  background-color: var(--color-primary);
  border-radius: 2px;
  transform: scale(1.15);
}

/* 侧栏底部 */
.rail-foot {
  flex: 1 1 100%;
  display: none;
  flex-direction: column;
  gap: 4px;
  padding: 0 var(--rail-pad) var(--space-3);
  margin-top: var(--space-2);
  border-top: var(--border-thin) dotted var(--color-contrast-line);
}
.site-header[data-open] .rail-foot { display: flex; }

.tick-rule {
  height: 5px;
  margin: var(--space-2) 0 var(--space-1);
  color: var(--color-contrast-line);
  background-image: repeating-linear-gradient(to right, currentColor 0 1px, transparent 1px 9px);
  background-repeat: repeat-x;
}
.rail-foot__stamp {
  max-width: none;
  font-size: var(--text-xs);
  color: color-mix(in srgb, var(--color-contrast-ink) 56%, transparent);
}
.rail-foot__link {
  align-self: flex-start;
  font-size: var(--text-xs);
  color: color-mix(in srgb, var(--color-contrast-ink) 82%, transparent);
  border-bottom: var(--border-thin) dotted currentColor;
  transition: color 140ms ease, border-color 140ms ease;
}
.rail-foot__link:hover { color: var(--color-primary); border-color: var(--color-primary); }
.rail-foot__icp {
  max-width: none;
  margin-top: 2px;
  font-size: var(--text-xs);
  color: color-mix(in srgb, var(--color-contrast-ink) 42%, transparent);
}

/* 滚动进度 */
.scroll-progress {
  position: fixed;
  top: 0;
  left: 0;
  right: 0;
  height: 2px;
  z-index: 120;
  background-color: transparent;
  pointer-events: none;
}
.scroll-progress__bar {
  display: block;
  width: 100%;
  height: 100%;
  background-color: var(--color-primary);
  transform: scaleX(0);
  transform-origin: 0 50%;
  opacity: 0;
  transition: opacity 160ms linear;
}

/* ------------------------------------------------------------
   页脚 · 极简单行
   ------------------------------------------------------------ */
.site-footer {
  border-top: var(--border-thin) dotted var(--color-line);
  background-color: var(--color-surface-alt);
  color: var(--color-ink-soft);
}
.site-footer__inner {
  display: flex;
  flex-wrap: wrap;
  align-items: center;
  justify-content: space-between;
  gap: var(--space-1) var(--space-4);
  width: 100%;
  max-width: var(--container);
  margin: 0 auto;
  padding: var(--space-3) var(--rail-pad);
  font-size: var(--text-xs);
}
.site-footer__brand {
  display: inline-flex;
  align-items: baseline;
  gap: 8px;
  max-width: none;
  color: var(--color-ink);
  font-weight: 600;
}
.site-footer__tag { font-weight: 400; color: var(--color-ink-muted); }
.site-footer__sep { color: var(--color-line); }
.site-footer__links {
  display: flex;
  flex-wrap: wrap;
  gap: 0 var(--space-3);
}
.site-footer__links a {
  color: var(--color-ink-soft);
  border-bottom: var(--border-thin) dotted var(--color-line);
  transition: color 140ms ease, border-color 140ms ease;
}
.site-footer__links a:hover { color: var(--color-primary); border-color: var(--color-primary); }
.site-footer__meta {
  display: inline-flex;
  flex-wrap: wrap;
  align-items: center;
  gap: 0 8px;
  max-width: none;
  color: var(--color-ink-muted);
}

/* ------------------------------------------------------------
   布局容器
   ------------------------------------------------------------ */
.container {
  width: 100%;
  max-width: var(--container);
  margin-inline: auto;
  padding-inline: var(--rail-pad);
}
.section { padding-block: var(--section-y); }
.section--lg { padding-block: var(--section-y-lg); }
.section--snug { padding-block: var(--space-4); }

/* ------------------------------------------------------------
   页面头与面包屑
   ------------------------------------------------------------ */
.breadcrumb {
  display: flex;
  flex-wrap: wrap;
  align-items: center;
  gap: 0 10px;
  padding-block: var(--space-2);
  font-family: var(--font-mono);
  font-size: var(--text-xs);
  color: var(--color-ink-muted);
}
.breadcrumb li { display: inline-flex; align-items: center; gap: 10px; }
.breadcrumb li + li::before { content: "/"; color: var(--color-line); }
.breadcrumb a {
  border-bottom: var(--border-thin) dotted currentColor;
  transition: color 140ms ease, border-color 140ms ease;
}
.breadcrumb a:hover { color: var(--color-primary); border-color: var(--color-primary); }
.breadcrumb [aria-current="page"] { color: var(--color-ink); }

.page-head {
  padding-block: var(--space-6) var(--space-4);
  border-bottom: var(--border-thin) dotted var(--color-line);
}
.page-head__kicker {
  font-family: var(--font-mono);
  font-size: var(--text-xs);
  letter-spacing: 0.1em;
  text-transform: uppercase;
  color: var(--color-primary);
}
.page-head__title {
  margin-top: var(--space-2);
  font-size: var(--text-4xl);
  max-width: 24ch;
}
.page-head__lede {
  margin-top: var(--space-3);
  font-size: var(--text-lg);
  color: var(--color-ink-soft);
}
.page-head__meta {
  margin-top: var(--space-3);
  display: flex;
  flex-wrap: wrap;
  gap: 4px var(--space-3);
  font-family: var(--font-mono);
  font-size: var(--text-xs);
  color: var(--color-ink-muted);
}

/* ------------------------------------------------------------
   时间轴组件
   ------------------------------------------------------------ */
.axis { position: relative; }
.axis__list { position: relative; }
.axis__list::before {
  content: "";
  position: absolute;
  left: 5px;
  top: 4px;
  bottom: 4px;
  border-left: var(--border-thin) dotted var(--color-line);
}
.axis__item {
  position: relative;
  padding: 0 0 var(--space-4) 30px;
}
.axis__item:last-child { padding-bottom: 0; }
.axis__node {
  position: absolute;
  left: 0;
  top: 6px;
  width: 11px;
  height: 11px;
  border-radius: 50%;
  background-color: var(--color-primary);
  transition: border-radius 140ms ease, background-color 140ms ease;
}
.axis__node--record { background-color: var(--color-primary); border-radius: 50%; }
.axis__node--quota { background-color: var(--color-accent); border-radius: var(--radius-sm); }
.axis__node--pending {
  background-color: transparent;
  border: var(--border-thick) solid var(--color-primary);
  border-radius: 50%;
}
.axis__stamp {
  display: block;
  font-family: var(--font-mono);
  font-size: var(--text-xs);
  letter-spacing: 0.04em;
  text-transform: uppercase;
  color: var(--color-ink-muted);
}
.axis__body { margin-top: 4px; }
.axis__body > * + * { margin-top: var(--space-2); }
.axis__item:hover .axis__node {
  border-radius: var(--radius-sm);
  background-color: color-mix(in srgb, var(--color-primary) 78%, var(--color-contrast-surface));
}

/* ------------------------------------------------------------
   徽标 / 标签
   ------------------------------------------------------------ */
.badge {
  display: inline-flex;
  align-items: center;
  gap: 5px;
  padding: 2px 7px;
  border: var(--border-thin) solid transparent;
  border-radius: var(--radius-sm);
  font-family: var(--font-mono);
  font-size: var(--text-xs);
  line-height: 1.6;
  white-space: nowrap;
  background-color: var(--color-surface-deep);
  color: var(--color-ink-soft);
}
.badge--primary {
  background-color: var(--color-primary-soft);
  color: color-mix(in srgb, var(--color-primary) 80%, var(--color-ink));
}
.badge--accent {
  background-color: var(--color-highlight);
  color: color-mix(in srgb, var(--color-accent) 76%, var(--color-ink));
}
.badge--solid {
  background-color: var(--color-primary);
  color: var(--color-primary-ink);
}
.badge--outline {
  background-color: transparent;
  border-color: var(--color-line);
  color: var(--color-ink-muted);
}
.badge--dark {
  background-color: transparent;
  border-color: var(--color-contrast-line);
  color: var(--color-contrast-ink);
}

/* ------------------------------------------------------------
   按钮
   ------------------------------------------------------------ */
.btn {
  display: inline-flex;
  align-items: center;
  gap: var(--space-1);
  padding: 10px 18px;
  border: var(--border-thin) solid var(--color-line);
  border-radius: var(--radius-sm);
  background-color: var(--color-surface);
  color: var(--color-ink);
  font-size: var(--text-sm);
  font-weight: 600;
  line-height: 1.4;
  transition: background-color 140ms ease, border-color 140ms ease, color 140ms ease;
}
.btn:hover {
  border-color: var(--color-primary);
  color: var(--color-primary);
  background-color: var(--color-primary-soft);
}
.btn--primary {
  background-color: var(--color-primary);
  border-color: var(--color-primary);
  color: var(--color-primary-ink);
}
.btn--primary:hover {
  background-color: color-mix(in srgb, var(--color-primary) 84%, var(--color-contrast-surface));
  border-color: color-mix(in srgb, var(--color-primary) 84%, var(--color-contrast-surface));
  color: var(--color-primary-ink);
}

/* ------------------------------------------------------------
   面板
   ------------------------------------------------------------ */
.panel {
  padding: var(--space-3);
  background-color: var(--color-surface-alt);
  border: var(--border-thin) solid var(--color-line);
  border-radius: var(--radius-md);
}
.panel--dark {
  background-color: var(--color-contrast-surface);
  border-color: var(--color-contrast-line);
  color: var(--color-contrast-ink);
}
.panel__head {
  display: flex;
  align-items: baseline;
  justify-content: space-between;
  gap: var(--space-2);
  padding-bottom: var(--space-2);
  margin-bottom: var(--space-3);
  border-bottom: var(--border-thin) dotted var(--color-line);
}
.panel--dark .panel__head { border-bottom-color: var(--color-contrast-line); }
.panel__body > * + * { margin-top: var(--space-2); }

/* ------------------------------------------------------------
   深色区块
   ------------------------------------------------------------ */
.surface-dark {
  background-color: var(--color-contrast-surface);
  color: var(--color-contrast-ink);
}
.surface-dark h1,
.surface-dark h2,
.surface-dark h3,
.surface-dark h4 { color: var(--color-contrast-ink); }
.surface-dark p { color: color-mix(in srgb, var(--color-contrast-ink) 88%, transparent); }

/* ------------------------------------------------------------
   网格
   ------------------------------------------------------------ */
.grid--12 {
  display: grid;
  grid-template-columns: minmax(0, 1fr);
  gap: var(--space-4);
}
.grid--split {
  display: grid;
  grid-template-columns: minmax(0, 1fr);
  gap: var(--space-4);
}

/* ------------------------------------------------------------
   图片容器
   ------------------------------------------------------------ */
.media-frame {
  position: relative;
  display: block;
  overflow: hidden;
  border-radius: var(--radius-md);
  background-color: var(--color-contrast-surface);
  background-image:
    linear-gradient(to right, color-mix(in srgb, var(--color-contrast-line) 72%, transparent) 1px, transparent 1px),
    linear-gradient(to bottom, color-mix(in srgb, var(--color-contrast-line) 72%, transparent) 1px, transparent 1px);
  background-size: 44px 44px, 44px 44px;
  isolation: isolate;
}
.media-frame--wide { aspect-ratio: 16 / 7; }
.media-frame--band { aspect-ratio: 21 / 8; }
.media-frame--tall { aspect-ratio: 4 / 5; }
.media-frame--square { aspect-ratio: 1 / 1; }
.media-frame__img {
  position: absolute;
  inset: 0;
  width: 100%;
  height: 100%;
  object-fit: cover;
}
.media-frame__scrim {
  position: absolute;
  inset: 0;
  background-image: var(--overlay-scrim);
  pointer-events: none;
}
.media-frame__body {
  position: absolute;
  inset: auto 0 0 0;
  z-index: 1;
  padding: var(--space-3);
  color: var(--color-contrast-ink);
}
.media-frame__body > * + * { margin-top: var(--space-1); }

/* ------------------------------------------------------------
   响应式 · 平板
   ------------------------------------------------------------ */
@media (min-width: 641px) {
  .grid--12 { grid-template-columns: repeat(2, minmax(0, 1fr)); }
  .page-head { padding-block: var(--space-8) var(--space-4); }
}

@media (min-width: 861px) {
  .grid--split { grid-template-columns: minmax(200px, 3fr) minmax(0, 9fr); gap: var(--gutter); }
  .site-footer__inner { flex-wrap: nowrap; }
}

/* ------------------------------------------------------------
   响应式 · 桌面：侧栏固定在左
   ------------------------------------------------------------ */
@media (min-width: 961px) {
  body { padding-left: var(--rail-w); }

  .site-header {
    position: fixed;
    top: 0;
    left: 0;
    bottom: 0;
    right: auto;
    width: var(--rail-w);
    border-bottom: 0;
    border-right: var(--border-thin) solid var(--color-contrast-line);
    overflow: hidden;
  }
  .rail-inner {
    flex-wrap: nowrap;
    flex-direction: column;
    align-items: stretch;
    height: 100%;
  }
  .brand {
    flex: 0 0 auto;
    flex-direction: column;
    align-items: flex-start;
    gap: 10px;
    padding: var(--space-4) var(--rail-pad) var(--space-3);
  }
  .nav-toggle { display: none; }
  .site-nav {
    flex: 1 1 auto;
    display: block;
    overflow-y: auto;
    padding: var(--space-2) var(--rail-pad);
  }
  .rail-foot {
    flex: 0 0 auto;
    display: flex;
    padding: var(--space-2) var(--rail-pad) var(--space-3);
    margin-top: 0;
  }
  .scroll-progress { left: var(--rail-w); }
  .grid--12 { grid-template-columns: repeat(12, minmax(0, 1fr)); gap: var(--gutter); }
}

/* ------------------------------------------------------------
   动效收敛
   ------------------------------------------------------------ */
@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-progress__bar { transition: none; }
}