:root {
  --color-surface: #fcfcfc;
  --color-surface-alt: #f2f2f2;
  --color-surface-deep: #e5e4e4;
  --color-ink: #393233;
  --color-ink-soft: #685e60;
  --color-ink-muted: #857a7c;
  --color-line: #d9d8d8;
  --color-primary: #e11e38;
  --color-primary-ink: #ffffff;
  --color-primary-soft: #f8dde1;
  --color-accent: #e91632;
  --color-accent-ink: #ffffff;
  --color-highlight: #f9d3d8;
  --color-focus: #e20926;
  --color-contrast-surface: #1e0f11;
  --color-contrast-ink: #e7e4e5;
  --color-contrast-line: #4a3e40;
  --color-contrast-accent: #ec324b;
  --overlay-scrim: linear-gradient(180deg, rgba(30, 15, 17, 0.35) 0%, rgba(30, 15, 17, 0.72) 55%, rgba(30, 15, 17, 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: 11.4px;
  --text-sm: 14.3px;
  --text-base: 16px;
  --text-lg: 20.0px;
  --text-xl: 25.0px;
  --text-2xl: 31.2px;
  --text-3xl: 39.1px;
  --text-4xl: 48.8px;
  --text-display: clamp(55px, 11.2vw, 144px);
  --text-figure: clamp(46px, 8.1vw, 104px);
  --weight-heading: 814;
  --weight-body: 400;
  --leading-body: 1.69;
  --leading-heading: 1.23;
  --tracking-heading: -0.017em;
  --radius-sm: 0px;
  --radius-md: 0px;
  --radius-lg: 0px;
  --radius-pill: 0px;
  --border-thin: 1px;
  --border-thick: 3px;
  --shadow-1: none;
  --shadow-2: none;
  --space-1: 8px;
  --space-2: 16px;
  --space-3: 24px;
  --space-4: 32px;
  --space-6: 48px;
  --space-8: 64px;
  --container: 1160px;
  --measure: 72ch;
  --gutter: 32px;
  --section-y: 91px;
  --section-y-lg: 127px;
}

/* ==========================================================================
   1. Reset
   ========================================================================== */

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

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

body {
  margin: 0;
  background-color: var(--color-surface);
  color: var(--color-ink);
  font-family: var(--font-body);
  font-size: var(--text-base);
  font-weight: var(--weight-body);
  line-height: var(--leading-body);
  text-rendering: optimizeLegibility;
}

img,
picture,
svg,
video {
  display: block;
  max-width: 100%;
  height: auto;
}

a { color: inherit; }

button,
input,
select,
textarea {
  font: inherit;
  color: inherit;
}

button { cursor: pointer; }

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

hr {
  border: 0;
  margin: 0;
}

::selection {
  background-color: var(--color-primary);
  color: var(--color-primary-ink);
}

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

[hidden] { display: none !important; }

/* ==========================================================================
   2. 中文排版基座
   ========================================================================== */

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);
}

p:last-child { margin-bottom: 0; }

strong { font-weight: 600; }

.display-title {
  font-family: var(--font-heading);
  font-size: var(--text-display);
  font-weight: var(--weight-heading);
  line-height: 0.94;
  letter-spacing: -0.035em;
  margin: 0;
}

.figure-num {
  display: block;
  font-family: var(--font-mono);
  font-size: var(--text-figure);
  font-weight: 600;
  font-variant-numeric: tabular-nums;
  line-height: 0.95;
  letter-spacing: -0.03em;
  color: var(--color-ink);
}

.num {
  font-family: var(--font-mono);
  font-variant-numeric: tabular-nums;
  font-weight: 600;
}

.lede {
  max-width: 46ch;
  margin: 0;
  font-size: var(--text-lg);
  line-height: 1.5;
  color: var(--color-ink-soft);
}

.eyebrow {
  display: inline-flex;
  align-items: center;
  gap: var(--space-2);
  font-family: var(--font-mono);
  font-size: var(--text-xs);
  font-weight: 400;
  letter-spacing: 0.16em;
  color: var(--color-ink-muted);
}

.prose {
  max-width: var(--measure);
  color: var(--color-ink);
}

.prose h2,
.prose h3 { margin: 0 0 var(--space-2); }

.prose ul,
.prose ol {
  margin: 0 0 var(--space-3);
  padding-left: 1.2em;
}

.prose ul { list-style: square; }
.prose ol { list-style: decimal; }
.prose li { margin-bottom: var(--space-1); }

.muted { color: var(--color-ink-muted); }
.small { font-size: var(--text-sm); }

/* ==========================================================================
   3. 骨架：容器 / 区块 / 网格 / 分隔
   ========================================================================== */

.shell {
  width: 100%;
  max-width: var(--container);
  margin-inline: auto;
  padding-inline: var(--space-4);
}

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

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

.rule {
  width: 100%;
  height: 0;
  border-top: var(--border-thin) solid var(--color-line);
}

.rule--dotted {
  border-top-style: dotted;
}

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

.col-2 { grid-column: span 2; }
.col-3 { grid-column: span 3; }
.col-4 { grid-column: span 4; }
.col-5 { grid-column: span 5; }
.col-6 { grid-column: span 6; }
.col-7 { grid-column: span 7; }
.col-8 { grid-column: span 8; }
.col-9 { grid-column: span 9; }
.col-10 { grid-column: span 10; }
.col-12 { grid-column: span 12; }

/* ==========================================================================
   4. 通用组件
   ========================================================================== */

.link-underline {
  position: relative;
  text-decoration: none;
}

.link-underline::after {
  content: "";
  position: absolute;
  left: 0;
  bottom: -2px;
  width: 100%;
  height: 1px;
  background-color: currentColor;
  transform: scaleX(0);
  transform-origin: left center;
  transition: transform 180ms ease-out;
}

.link-underline:hover::after,
.link-underline:focus-visible::after {
  transform: scaleX(1);
}

.tag {
  display: inline-flex;
  align-items: center;
  gap: var(--space-1);
  padding: 2px var(--space-1);
  background-color: var(--color-surface-deep);
  color: var(--color-ink-soft);
  font-size: var(--text-xs);
  letter-spacing: 0.08em;
  line-height: 1.5;
  white-space: nowrap;
}

.tag--accent {
  background-color: var(--color-primary-soft);
  color: var(--color-primary);
  font-weight: 600;
}

.btn {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  gap: var(--space-2);
  padding: 12px var(--space-4);
  background-color: transparent;
  border: var(--border-thin) solid var(--color-ink);
  color: var(--color-ink);
  font-family: var(--font-body);
  font-size: var(--text-sm);
  font-weight: 600;
  letter-spacing: 0.04em;
  line-height: 1.25;
  text-decoration: none;
  transition: background-color 160ms linear, border-color 160ms linear, color 160ms linear;
}

.btn:hover {
  background-color: var(--color-contrast-surface);
  border-color: var(--color-contrast-surface);
  color: var(--color-contrast-ink);
}

.btn--primary {
  background-color: var(--color-primary);
  border-color: var(--color-primary);
  color: var(--color-primary-ink);
}

.btn--primary:hover {
  background-color: var(--color-accent);
  border-color: var(--color-accent);
  color: var(--color-accent-ink);
}

.btn--quiet {
  border-color: var(--color-line);
  color: var(--color-ink-soft);
}

.btn--quiet:hover {
  background-color: transparent;
  border-color: var(--color-primary);
  color: var(--color-primary);
}

.data-table {
  width: 100%;
  border-collapse: collapse;
  font-size: var(--text-sm);
  text-align: left;
}

.data-table caption {
  padding-bottom: var(--space-2);
  font-family: var(--font-mono);
  font-size: var(--text-xs);
  letter-spacing: 0.16em;
  color: var(--color-ink-muted);
  text-align: left;
}

.data-table th {
  padding: var(--space-2) var(--space-3);
  background-color: var(--color-surface-alt);
  border-bottom: var(--border-thin) solid var(--color-line);
  font-size: var(--text-xs);
  font-weight: 600;
  letter-spacing: 0.1em;
  color: var(--color-ink-soft);
  white-space: nowrap;
}

.data-table td {
  padding: var(--space-2) var(--space-3);
  border-bottom: var(--border-thin) dotted var(--color-line);
  vertical-align: top;
}

.data-table tbody tr {
  transition: background-color 160ms linear;
}

.data-table tbody tr:hover {
  background-color: var(--color-highlight);
}

.data-table .num { color: var(--color-ink); }

.breadcrumb {
  display: flex;
  flex-wrap: wrap;
  align-items: center;
  gap: var(--space-2);
  font-family: var(--font-mono);
  font-size: var(--text-xs);
  letter-spacing: 0.06em;
  color: var(--color-ink-muted);
}

.breadcrumb__item {
  display: inline-flex;
  align-items: center;
  gap: var(--space-2);
}

.breadcrumb__item + .breadcrumb__item::before {
  content: "/";
  color: var(--color-line);
}

.breadcrumb__link {
  text-decoration: none;
  color: var(--color-ink-soft);
  transition: color 160ms linear;
}

.breadcrumb__link:hover { color: var(--color-primary); }

.breadcrumb__current { color: var(--color-ink); }

.callout {
  padding: var(--space-6) var(--space-4);
  background-color: var(--color-contrast-surface);
  color: var(--color-contrast-ink);
}

.callout__title {
  margin: 0 0 var(--space-2);
  color: var(--color-contrast-ink);
  font-size: var(--text-xl);
}

.callout p {
  color: var(--color-contrast-ink);
  opacity: 0.86;
}

.callout a {
  color: var(--color-contrast-accent);
}

.callout .rule {
  border-top-color: var(--color-contrast-line);
}

.callout .num,
.callout .figure-num {
  color: var(--color-contrast-accent);
}

.filter-bar {
  display: flex;
  flex-wrap: wrap;
  align-items: center;
  gap: var(--space-2);
  padding-block: var(--space-2);
  border-top: var(--border-thin) solid var(--color-line);
  border-bottom: var(--border-thin) solid var(--color-line);
}

.filter-bar__label {
  margin-right: var(--space-1);
  font-family: var(--font-mono);
  font-size: var(--text-xs);
  letter-spacing: 0.16em;
  color: var(--color-ink-muted);
}

.filter-chip {
  padding: 4px 10px;
  background-color: transparent;
  border: var(--border-thin) solid var(--color-line);
  color: var(--color-ink-soft);
  font-size: var(--text-xs);
  letter-spacing: 0.06em;
  line-height: 1.5;
  transition: background-color 160ms linear, border-color 160ms linear, color 160ms linear;
}

.filter-chip:hover {
  border-color: var(--color-primary);
  color: var(--color-primary);
}

.filter-chip[aria-pressed="true"] {
  background-color: var(--color-primary);
  border-color: var(--color-primary);
  color: var(--color-primary-ink);
}

.filter-empty {
  padding: var(--space-3) 0;
  font-size: var(--text-sm);
  color: var(--color-ink-muted);
}

/* ==========================================================================
   5. 图片容器
   ========================================================================== */

.media {
  position: relative;
  display: block;
  overflow: hidden;
  background-color: var(--color-contrast-surface);
}

.media__img {
  width: 100%;
  height: 100%;
  object-fit: cover;
}

.media__scrim {
  position: absolute;
  inset: 0;
  background: var(--overlay-scrim);
  pointer-events: none;
}

.media__body {
  position: absolute;
  inset: auto 0 0 0;
  padding: var(--space-3) var(--space-4);
  color: var(--color-contrast-ink);
}

.media__body > * { margin: 0; }

.media__body h2,
.media__body h3 {
  color: var(--color-contrast-ink);
}

.media__label {
  display: inline-block;
  margin-bottom: var(--space-1);
  font-family: var(--font-mono);
  font-size: var(--text-xs);
  letter-spacing: 0.16em;
  color: var(--color-contrast-accent);
}

.media--wide { aspect-ratio: 16 / 9; }
.media--tall { aspect-ratio: 3 / 4; }
.media--square { aspect-ratio: 1 / 1; }
.media--banner { aspect-ratio: 21 / 9; }

/* ==========================================================================
   6. 跳转链接
   ========================================================================== */

.skip-link {
  position: absolute;
  left: var(--space-4);
  top: -120px;
  z-index: 200;
  padding: 10px var(--space-2);
  background-color: var(--color-contrast-surface);
  color: var(--color-contrast-ink);
  font-size: var(--text-sm);
  text-decoration: none;
  transition: top 160ms ease-out;
}

.skip-link:focus {
  top: var(--space-2);
}

/* ==========================================================================
   7. 头部
   ========================================================================== */

.site-header {
  position: sticky;
  top: 0;
  z-index: 100;
  background-color: var(--color-surface);
  border-bottom: var(--border-thin) solid var(--color-line);
}

.site-header__inner {
  display: flex;
  align-items: center;
  gap: var(--space-4);
  min-height: 72px;
  padding-block: var(--space-2);
}

.brand {
  margin-right: auto;
  min-width: 0;
}

.brand__link {
  display: flex;
  flex-direction: column;
  gap: 2px;
  text-decoration: none;
}

.brand__name {
  font-family: var(--font-heading);
  font-size: var(--text-lg);
  font-weight: var(--weight-heading);
  line-height: 1.1;
  letter-spacing: var(--tracking-heading);
  color: var(--color-ink);
}

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

.status-badge {
  display: inline-flex;
  align-items: center;
  gap: var(--space-2);
  margin: 0;
  padding: 6px 10px;
  background-color: var(--color-surface-alt);
  border-left: var(--border-thick) solid var(--color-primary);
  font-size: var(--text-xs);
  letter-spacing: 0.06em;
  color: var(--color-ink-soft);
  white-space: nowrap;
}

.status-badge__dot {
  width: 6px;
  height: 6px;
  background-color: var(--color-primary);
  flex: 0 0 auto;
}

.status-badge__rule {
  width: 1px;
  height: 12px;
  background-color: var(--color-line);
  flex: 0 0 auto;
}

.status-badge__round {
  font-family: var(--font-mono);
  font-weight: 600;
  font-variant-numeric: tabular-nums;
  letter-spacing: 0;
  color: var(--color-ink);
}

.nav-toggle {
  display: none;
  align-items: center;
  gap: var(--space-2);
  padding: 8px 12px;
  background-color: transparent;
  border: var(--border-thin) solid var(--color-line);
  color: var(--color-ink-soft);
  font-size: var(--text-xs);
  letter-spacing: 0.12em;
  transition: border-color 160ms linear, color 160ms linear;
}

.nav-toggle:hover {
  border-color: var(--color-primary);
  color: var(--color-primary);
}

.nav-toggle__bars {
  display: grid;
  gap: 3px;
  width: 14px;
}

.nav-toggle__bars span {
  display: block;
  height: 1px;
  background-color: currentColor;
}

.nav-toggle__label { line-height: 1; }

.site-nav__list {
  display: flex;
  align-items: center;
  gap: var(--space-3);
}

.site-nav__link {
  position: relative;
  display: inline-flex;
  align-items: baseline;
  gap: 6px;
  padding-bottom: 3px;
  text-decoration: none;
  font-size: var(--text-sm);
  font-weight: 600;
  color: var(--color-ink-soft);
  transition: color 160ms linear;
}

.site-nav__idx {
  font-family: var(--font-mono);
  font-size: var(--text-xs);
  font-weight: 400;
  letter-spacing: 0;
  color: var(--color-ink-muted);
  transition: color 160ms linear;
}

.site-nav__link::after {
  content: "";
  position: absolute;
  left: 0;
  bottom: 0;
  width: 100%;
  height: 2px;
  background-color: var(--color-primary);
  transform: scaleX(0);
  transform-origin: left center;
  transition: transform 180ms ease-out;
}

.site-nav__link:hover { color: var(--color-ink); }
.site-nav__link:hover::after { transform: scaleX(1); }

.site-nav__link[aria-current="page"] { color: var(--color-primary); }
.site-nav__link[aria-current="page"] .site-nav__idx { color: var(--color-primary); }
.site-nav__link[aria-current="page"]::after { transform: scaleX(1); }

.scroll-progress {
  position: absolute;
  left: 0;
  bottom: -1px;
  width: 0;
  height: 3px;
  background-color: var(--color-primary);
}

/* ==========================================================================
   8. 页脚
   ========================================================================== */

.site-footer {
  border-top: var(--border-thin) solid var(--color-line);
  background-color: var(--color-surface);
}

.site-footer__inner {
  display: flex;
  flex-wrap: wrap;
  align-items: baseline;
  gap: var(--space-3) var(--space-6);
  padding-block: var(--space-4) var(--section-y);
}

.site-footer__brand {
  display: flex;
  flex-direction: column;
  gap: 4px;
  margin-right: auto;
}

.site-footer__name {
  font-family: var(--font-heading);
  font-size: var(--text-sm);
  font-weight: var(--weight-heading);
  letter-spacing: var(--tracking-heading);
  color: var(--color-ink);
}

.site-footer__icp {
  font-family: var(--font-mono);
  font-size: var(--text-xs);
  color: var(--color-ink-muted);
}

.site-footer__links {
  display: flex;
  flex-wrap: wrap;
  gap: var(--space-3);
}

.site-footer__link {
  font-size: var(--text-sm);
  color: var(--color-ink-soft);
  transition: color 160ms linear;
}

.site-footer__link:hover { color: var(--color-primary); }

.site-footer__legal {
  margin: 0;
  font-family: var(--font-mono);
  font-size: var(--text-xs);
  color: var(--color-ink-muted);
}

.site-footer__mail { word-break: break-all; }

/* ==========================================================================
   9. 响应式
   ========================================================================== */

@media (max-width: 1024px) {
  .site-header__inner {
    display: grid;
    grid-template-columns: minmax(0, 1fr) auto;
    align-items: center;
    gap: var(--space-2) var(--space-3);
    padding-block: var(--space-2);
  }

  .brand {
    grid-column: 1;
    grid-row: 1;
    margin-right: 0;
  }

  .nav-toggle {
    display: inline-flex;
    grid-column: 2;
    grid-row: 1;
    justify-self: end;
  }

  .status-badge {
    grid-column: 1 / -1;
    grid-row: 2;
    justify-self: start;
  }

  .site-nav {
    grid-column: 1 / -1;
    grid-row: 3;
    display: none;
    padding-top: var(--space-2);
    border-top: var(--border-thin) dotted var(--color-line);
  }

  .site-header[data-open="true"] .site-nav { display: block; }

  .site-nav__list {
    flex-direction: column;
    align-items: stretch;
    gap: 0;
  }

  .site-nav__item {
    border-bottom: var(--border-thin) dotted var(--color-line);
  }

  .site-nav__item:last-child { border-bottom: 0; }

  .site-nav__link {
    display: flex;
    align-items: baseline;
    width: 100%;
    padding: var(--space-2) 0;
    font-size: var(--text-base);
  }

  .site-nav__link::after { display: none; }

  .site-footer__inner {
    flex-direction: column;
    align-items: flex-start;
    gap: var(--space-3);
    padding-block: var(--space-4) var(--space-8);
  }

  .site-footer__brand { margin-right: 0; }
}

@media (max-width: 960px) {
  .grid {
    grid-template-columns: repeat(6, minmax(0, 1fr));
    gap: var(--space-3);
  }

  .col-2,
  .col-3 { grid-column: span 3; }

  .col-4,
  .col-5,
  .col-6,
  .col-7,
  .col-8,
  .col-9,
  .col-10,
  .col-12 { grid-column: span 6; }
}

@media (max-width: 640px) {
  .shell { padding-inline: var(--space-3); }

  .section { padding-block: var(--space-8); }
  .section--lg { padding-block: var(--space-8); }

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

  .grid > [class*="col-"] { grid-column: 1 / -1; }

  .lede { font-size: var(--text-base); }

  .callout { padding: var(--space-4) var(--space-3); }

  .media__body { padding: var(--space-3); }

  .data-table th,
  .data-table td { padding: var(--space-1) var(--space-2); }
}

/* ==========================================================================
   10. 无障碍与动效降级
   ========================================================================== */

@media (prefers-reduced-motion: reduce) {
  html { scroll-behavior: auto; }

  *,
  *::before,
  *::after {
    animation-duration: 0.01ms !important;
    animation-iteration-count: 1 !important;
    transition-duration: 0.01ms !important;
    scroll-behavior: auto !important;
  }
}