/* =============================================
   乐竞体育 Site Kit — /assets/site.css
   共享样式：变量、reset、排版、头部、页脚、
   通用按钮、面包屑、容器、网格与基础组件
   ============================================= */

/* ---------- 1. CSS 变量 ---------- */
:root {
  --deep-navy: #0B1D3A;
  --panel-navy: #12294D;
  --electric-green: #39FF14;
  --electric-violet: #9D00FF;
  --line-blue: #234D7D;
  --text-primary: #E6F1FF;
  --text-secondary: #93A9C6;
  --text-dim: #5C7CA6;
  --warning: #FFB300;
  --success: #2FE6A9;

  --font-display: "Orbitron", "Source Han Serif SC", "Noto Serif SC", "Songti SC", "SimSun", serif;
  --font-body: "IBM Plex Sans SC", "Noto Sans SC", "PingFang SC", "Microsoft YaHei", "Segoe UI", sans-serif;
  --font-mono: "IBM Plex Mono", "Cascadia Code", "SF Mono", Consolas, "Liberation Mono", monospace;

  --header-h: 72px;
  --container-w: 1360px;
  --ease-out: cubic-bezier(0.22, 1, 0.36, 1);
}

/* ---------- 2. Reset 与全局 ---------- */
*,
*::before,
*::after {
  box-sizing: border-box;
}

[hidden] {
  display: none !important;
}

html {
  scroll-behavior: smooth;
  min-height: 100%;
  background: var(--deep-navy);
}

body {
  min-height: 100vh;
  margin: 0;
  overflow-x: hidden;
  background: var(--deep-navy);
  color: var(--text-primary);
  font-family: var(--font-body);
  font-size: 1rem;
  line-height: 1.7;
  -webkit-font-smoothing: antialiased;
  text-rendering: optimizeLegibility;
}

#main-content {
  min-height: 62vh;
}

h1, h2, h3, h4, h5, h6, p, ul, ol, dl, figure, blockquote {
  margin: 0;
}

ul, ol {
  padding: 0;
}

ul[class], ol[class] {
  list-style: none;
}

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

a {
  color: var(--text-secondary);
  text-decoration: none;
}

a:hover {
  color: var(--electric-green);
}

strong {
  font-weight: 700;
  color: var(--text-primary);
}

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

::selection {
  background: rgba(57, 255, 20, 0.25);
  color: var(--text-primary);
}

:focus-visible {
  outline: 3px solid var(--electric-green);
  outline-offset: 2px;
  border-radius: 3px;
}

.mono {
  font-family: var(--font-mono);
}

/* ---------- 3. 中文与标题排版 ---------- */
h1, h2, h3, h4, h5, h6 {
  font-family: var(--font-display);
  color: var(--text-primary);
  line-height: 1.18;
  font-weight: 900;
  letter-spacing: 0.02em;
  margin-bottom: 0.75rem;
}

h1 {
  font-size: clamp(2.5rem, 5vw, 4.5rem);
}

h2 {
  font-size: clamp(1.8rem, 3.4vw, 2.8rem);
}

h3 {
  font-size: clamp(1.3rem, 2.2vw, 1.75rem);
}

p {
  margin-bottom: 1rem;
}

/* ---------- 4. 内容容器 ---------- */
.container {
  width: min(100% - 2rem, var(--container-w));
  margin-inline: auto;
}

.container--wide {
  width: min(100% - 1rem, 1560px);
  margin-inline: auto;
}

.container--narrow {
  width: min(100% - 3rem, 920px);
  margin-inline: auto;
}

/* ---------- 5. 通用按钮 ---------- */
.btn {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  gap: 0.5rem;
  min-height: 42px;
  padding: 0.55rem 1.25rem;
  font-family: var(--font-body);
  font-size: 0.875rem;
  font-weight: 600;
  line-height: 1;
  color: var(--text-primary);
  background: transparent;
  border: 1px solid var(--line-blue);
  border-radius: 4px;
  cursor: pointer;
  text-decoration: none;
  clip-path: polygon(8px 0, 100% 0, calc(100% - 8px) 100%, 0 100%);
  transition: background-color 0.18s var(--ease-out), color 0.18s var(--ease-out), border-color 0.18s var(--ease-out), transform 0.18s var(--ease-out);
}

.btn:hover {
  color: var(--text-primary);
  border-color: rgba(57, 255, 20, 0.5);
  transform: translateY(-1px);
}

.btn--primary {
  background: linear-gradient(120deg, var(--electric-green) 0%, #8dff5a 80%);
  color: var(--deep-navy);
  font-weight: 800;
  border-color: transparent;
  filter: drop-shadow(0 0 10px rgba(57, 255, 20, 0.25));
}

.btn--primary:hover {
  background: linear-gradient(120deg, #8dff5a 0%, var(--electric-green) 80%);
  color: var(--deep-navy);
  filter: drop-shadow(0 0 16px rgba(57, 255, 20, 0.4));
  transform: translateY(-1px);
}

.btn--ghost {
  border-color: rgba(157, 0, 255, 0.6);
  color: var(--text-primary);
  background: rgba(157, 0, 255, 0.08);
}

.btn--ghost:hover {
  border-color: var(--electric-violet);
  background: rgba(157, 0, 255, 0.18);
}

.btn--header {
  min-height: 36px;
  padding: 0.45rem 0.95rem;
  font-family: var(--font-mono);
  font-size: 0.78rem;
  letter-spacing: 0.08em;
  text-transform: uppercase;
}

/* ---------- 6. 跳过链接 ---------- */
.skip-link {
  position: fixed;
  top: -60px;
  left: 1rem;
  z-index: 300;
  display: inline-flex;
  align-items: center;
  min-height: 44px;
  padding: 0.5rem 1rem;
  background: var(--electric-green);
  color: var(--deep-navy);
  font-weight: 800;
  font-size: 0.875rem;
  border-radius: 4px;
  text-decoration: none;
  transition: top 0.18s var(--ease-out);
}

.skip-link:hover {
  color: var(--deep-navy);
}

.skip-link:focus-visible {
  top: 1rem;
}

/* ---------- 7. 滚动进度条 ---------- */
.scroll-progress {
  position: fixed;
  top: 0;
  left: 0;
  z-index: 200;
  width: 0;
  height: 3px;
  background: linear-gradient(90deg, var(--electric-green), var(--electric-violet));
  pointer-events: none;
  box-shadow: 0 0 12px rgba(57, 255, 20, 0.5);
}

/* ---------- 8. 站点头部 ---------- */
.site-header {
  position: sticky;
  top: 0;
  z-index: 100;
  background: rgba(11, 29, 58, 0.96);
  backdrop-filter: blur(14px);
  -webkit-backdrop-filter: blur(14px);
  border-bottom: 1px solid var(--line-blue);
  isolation: isolate;
}

.site-header::before {
  content: "";
  position: absolute;
  top: 0;
  left: 0;
  z-index: 1;
  width: 100%;
  height: 3px;
  background: linear-gradient(90deg, var(--electric-violet) 0 16%, var(--electric-green) 16% 34%, transparent 34%);
  pointer-events: none;
}

.site-header::after {
  content: "";
  position: absolute;
  left: 0;
  right: 0;
  bottom: -1px;
  z-index: 1;
  height: 1px;
  background: repeating-linear-gradient(90deg, var(--line-blue) 0 8px, transparent 8px 16px);
  opacity: 0.7;
  pointer-events: none;
}

.site-header__inner {
  position: relative;
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 1.25rem;
  width: min(100% - 2rem, 1400px);
  min-height: var(--header-h);
  margin-inline: auto;
}

.site-header__actions {
  display: flex;
  align-items: center;
  gap: 0.75rem;
  flex-shrink: 0;
}

/* ---------- 9. 品牌标识 ---------- */
.site-brand {
  display: inline-flex;
  align-items: center;
  gap: 0.65rem;
  color: var(--text-primary);
  flex-shrink: 0;
}

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

.site-brand__mark {
  width: 42px;
  height: 42px;
  filter: drop-shadow(0 0 10px rgba(57, 255, 20, 0.3));
}

.site-brand__name {
  font-family: var(--font-display);
  font-size: 1.35rem;
  font-weight: 900;
  letter-spacing: 0.05em;
  line-height: 1;
}

.site-brand__version {
  font-family: var(--font-mono);
  font-size: 0.66rem;
  letter-spacing: 0.08em;
  color: var(--electric-green);
  border: 1px solid rgba(57, 255, 20, 0.45);
  border-radius: 2px;
  padding: 2px 6px;
  transform: translateY(1px);
}

.site-brand--footer .site-brand__mark {
  width: 36px;
  height: 36px;
}

.site-brand--footer .site-brand__name {
  font-size: 1.15rem;
}

/* ---------- 10. 主导航 ---------- */
.site-nav__list {
  display: flex;
  align-items: center;
  gap: 0.15rem;
  list-style: none;
  margin: 0;
  padding: 0;
}

.site-nav__link {
  position: relative;
  display: block;
  padding: 0.5rem 0.8rem;
  font-size: 0.84rem;
  font-weight: 500;
  letter-spacing: 0.04em;
  color: var(--text-secondary);
  white-space: nowrap;
  border: 1px solid transparent;
  transition: color 0.18s var(--ease-out), background-color 0.18s var(--ease-out), border-color 0.18s var(--ease-out);
}

.site-nav__link:hover {
  color: var(--electric-green);
}

.site-nav__link:not([aria-current="page"]):hover {
  background: rgba(57, 255, 20, 0.05);
  border-color: rgba(57, 255, 20, 0.25);
}

.site-nav__link[aria-current="page"] {
  color: var(--electric-green);
  background: rgba(57, 255, 20, 0.08);
  border-color: rgba(57, 255, 20, 0.32);
}

.site-nav__link[aria-current="page"]::after {
  content: "";
  position: absolute;
  left: 50%;
  bottom: 4px;
  width: 4px;
  height: 4px;
  background: var(--electric-green);
  transform: translateX(-50%) rotate(45deg);
}

/* ---------- 11. 移动菜单按钮 ---------- */
.nav-toggle {
  display: none;
  flex-direction: column;
  align-items: center;
  justify-content: center;
  gap: 5px;
  width: 44px;
  height: 44px;
  padding: 0;
  background: transparent;
  border: 1px solid var(--line-blue);
  border-radius: 4px;
  cursor: pointer;
  transition: border-color 0.18s var(--ease-out), background-color 0.18s var(--ease-out);
}

.nav-toggle:hover {
  border-color: rgba(57, 255, 20, 0.5);
  background: rgba(57, 255, 20, 0.06);
}

.nav-toggle__bar {
  width: 20px;
  height: 2px;
  background: var(--electric-green);
  transition: transform 0.18s var(--ease-out), opacity 0.18s var(--ease-out);
}

.nav-toggle[aria-expanded="true"] .nav-toggle__bar:nth-child(1) {
  transform: translateY(7px) rotate(45deg);
}

.nav-toggle[aria-expanded="true"] .nav-toggle__bar:nth-child(2) {
  opacity: 0;
}

.nav-toggle[aria-expanded="true"] .nav-toggle__bar:nth-child(3) {
  transform: translateY(-7px) rotate(-45deg);
}

/* ---------- 12. 站点页脚 ---------- */
.site-footer {
  position: relative;
  margin-top: auto;
  background:
    radial-gradient(ellipse 60% 80% at 85% -20%, rgba(157, 0, 255, 0.12), transparent 60%),
    radial-gradient(ellipse 40% 60% at 10% 110%, rgba(57, 255, 20, 0.06), transparent 60%),
    var(--deep-navy);
  border-top: 1px solid var(--line-blue);
  overflow: hidden;
}

.site-footer::before {
  content: "";
  position: absolute;
  top: 0;
  left: 0;
  right: 0;
  height: 2px;
  background:
    linear-gradient(90deg, var(--electric-violet) 0 120px, transparent 120px 0) left top / 100% 100% no-repeat,
    linear-gradient(90deg, transparent calc(100% - 120px), var(--electric-green) calc(100% - 120px)) right top / 100% 100% no-repeat;
  opacity: 0.8;
}

.site-footer__top {
  display: grid;
  grid-template-columns: minmax(280px, 1.6fr) 1fr 1fr 1fr;
  gap: 2.25rem;
  width: min(100% - 2rem, 1400px);
  margin-inline: auto;
  padding: 3.25rem 0 2.5rem;
}

.site-footer__brand {
  display: grid;
  align-content: start;
  gap: 1.1rem;
}

.site-footer__desc {
  max-width: 38ch;
  font-size: 0.875rem;
  color: var(--text-secondary);
  border-left: 2px solid var(--electric-violet);
  padding-left: 1rem;
  line-height: 1.8;
}

.site-footer__contact {
  display: grid;
  gap: 0.35rem;
  list-style: none;
  font-family: var(--font-mono);
  font-size: 0.75rem;
  letter-spacing: 0.02em;
  color: var(--text-dim);
}

.site-footer__col {
  display: grid;
  align-content: start;
  gap: 0.4rem;
}

.site-footer__title {
  display: inline-block;
  font-family: var(--font-display);
  font-size: 0.82rem;
  font-weight: 900;
  letter-spacing: 0.16em;
  text-transform: uppercase;
  color: var(--text-primary);
  padding-bottom: 0.4rem;
  margin-bottom: 0.55rem;
  border-bottom: 1px solid var(--line-blue);
}

.site-footer__col ul {
  list-style: none;
  display: grid;
  gap: 0.45rem;
}

.site-footer__col a {
  font-size: 0.875rem;
  color: var(--text-secondary);
  text-decoration: none;
  transition: color 0.18s var(--ease-out), padding-left 0.18s var(--ease-out);
}

.site-footer__col a:hover {
  color: var(--electric-green);
  padding-left: 4px;
}

.site-footer__bottom {
  display: flex;
  flex-wrap: wrap;
  align-items: center;
  justify-content: space-between;
  gap: 0.5rem 1.5rem;
  width: min(100% - 2rem, 1400px);
  margin-inline: auto;
  padding: 1.1rem 0;
  border-top: 1px solid rgba(35, 77, 125, 0.7);
  font-family: var(--font-mono);
  font-size: 0.72rem;
  color: var(--text-dim);
}

.site-footer__note {
  flex-basis: 100%;
  text-align: center;
  font-size: 0.72rem;
  color: var(--text-dim);
}

/* ---------- 13. 面包屑 ---------- */
.breadcrumb {
  display: flex;
  flex-wrap: wrap;
  align-items: center;
  gap: 0.4rem;
  list-style: none;
  margin: 0;
  padding: 1rem 0 0;
  font-family: var(--font-mono);
  font-size: 0.78rem;
  color: var(--text-dim);
}

.breadcrumb__item {
  display: inline-flex;
  align-items: center;
}

.breadcrumb__item + .breadcrumb__item::before {
  content: "/";
  margin-right: 0.4rem;
  color: var(--line-blue);
}

.breadcrumb__link {
  color: var(--text-secondary);
  text-decoration: none;
  transition: color 0.18s var(--ease-out);
}

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

.breadcrumb [aria-current="page"] {
  color: var(--electric-green);
}

/* ---------- 14. 章节布局 ---------- */
.section {
  position: relative;
  padding: clamp(3rem, 7vw, 6rem) 0;
}

.section--tight {
  padding: clamp(1.75rem, 3vw, 2.75rem) 0;
}

.section--alt {
  background: var(--panel-navy);
}

.section--hero {
  padding: clamp(3.5rem, 9vw, 8rem) 0 clamp(2.5rem, 6vw, 5rem);
}

.section-label {
  display: inline-flex;
  align-items: center;
  gap: 0.6rem;
  font-family: var(--font-mono);
  font-size: 0.72rem;
  font-weight: 500;
  letter-spacing: 0.2em;
  text-transform: uppercase;
  color: var(--electric-green);
  margin-bottom: 0.9rem;
}

.section-label::before {
  content: "";
  width: 30px;
  height: 2px;
  background: var(--electric-green);
  display: inline-block;
  flex-shrink: 0;
}

.section-title {
  margin-bottom: 0.8rem;
}

.section-lead {
  max-width: 62ch;
  font-size: 1.0625rem;
  color: var(--text-secondary);
}

/* ---------- 15. 网格 ---------- */
.grid {
  display: grid;
  gap: 1.5rem;
}

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

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

.grid--4 {
  grid-template-columns: repeat(4, minmax(0, 1fr));
}

/* ---------- 16. 卡片 ---------- */
.card {
  position: relative;
  display: block;
  background:
    linear-gradient(145deg, rgba(255, 255, 255, 0.02), transparent 40%),
    var(--panel-navy);
  border: 1px solid var(--line-blue);
  border-radius: 6px;
  padding: 1.5rem;
  overflow: hidden;
  transition: transform 0.18s var(--ease-out), border-color 0.18s var(--ease-out), box-shadow 0.18s var(--ease-out);
}

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

.card:hover {
  transform: translateY(-3px);
  border-color: rgba(57, 255, 20, 0.45);
  box-shadow: 0 14px 40px rgba(0, 0, 0, 0.35), 0 0 0 1px rgba(57, 255, 20, 0.08);
}

.card--accent {
  border-top: 3px solid var(--electric-violet);
}

.card--green {
  border-top: 3px solid var(--electric-green);
}

.card--green:hover {
  border-top-color: var(--electric-green);
}

/* ---------- 17. 数据指标 ---------- */
.stat {
  display: grid;
  gap: 0.2rem;
}

.stat__value {
  font-family: var(--font-mono);
  font-size: clamp(1.75rem, 3vw, 2.6rem);
  font-weight: 800;
  line-height: 1;
  letter-spacing: -0.02em;
  color: var(--electric-green);
  font-variant-numeric: tabular-nums;
}

.stat__label {
  font-size: 0.8125rem;
  color: var(--text-dim);
  letter-spacing: 0.06em;
}

.stat__trend {
  font-family: var(--font-mono);
  font-size: 0.78rem;
  color: var(--warning);
}

/* ---------- 18. 数据表 ---------- */
.data-table {
  width: 100%;
  border-collapse: collapse;
  font-family: var(--font-mono);
  font-size: 0.875rem;
  font-variant-numeric: tabular-nums;
  background: rgba(18, 41, 77, 0.45);
  border: 1px solid var(--line-blue);
}

.data-table th,
.data-table td {
  text-align: left;
  padding: 0.72rem 0.85rem;
  border-bottom: 1px solid rgba(35, 77, 125, 0.55);
}

.data-table th {
  font-size: 0.72rem;
  letter-spacing: 0.12em;
  text-transform: uppercase;
  color: var(--text-dim);
  background: rgba(11, 29, 58, 0.6);
}

.data-table td {
  color: var(--text-primary);
}

.data-table tbody tr:hover {
  background: rgba(57, 255, 20, 0.045);
}

.data-table tbody tr:last-child td {
  border-bottom: 0;
}

/* ---------- 19. 图片容器 ---------- */
.media-frame {
  position: relative;
  display: block;
  aspect-ratio: 16 / 9;
  background: var(--panel-navy);
  border: 1px solid var(--line-blue);
  overflow: hidden;
  isolation: isolate;
}

.media-frame::before {
  content: "";
  position: absolute;
  inset: 0;
  z-index: -1;
  background:
    linear-gradient(135deg, rgba(157, 0, 255, 0.18) 0, transparent 55%),
    linear-gradient(315deg, rgba(57, 255, 20, 0.08) 0, transparent 60%);
}

.media-frame::after {
  content: attr(data-meta);
  position: absolute;
  right: 0.75rem;
  bottom: 0.65rem;
  z-index: 2;
  font-family: var(--font-mono);
  font-size: 0.62rem;
  letter-spacing: 0.16em;
  text-transform: uppercase;
  color: var(--text-dim);
  background: rgba(11, 29, 58, 0.7);
  padding: 0.15rem 0.5rem;
  border-left: 2px solid var(--electric-green);
}

.media-frame--tall {
  aspect-ratio: 4 / 5;
}

.media-frame--wide {
  aspect-ratio: 21 / 9;
}

.media-frame img {
  width: 100%;
  height: 100%;
  object-fit: cover;
  transition: transform 0.3s var(--ease-out);
}

.media-frame:hover img {
  transform: scale(1.03);
}

/* ---------- 20. 徽标、标签、状态点 ---------- */
.badge {
  display: inline-flex;
  align-items: center;
  gap: 0.4rem;
  font-family: var(--font-mono);
  font-size: 0.68rem;
  letter-spacing: 0.08em;
  text-transform: uppercase;
  padding: 0.28rem 0.65rem;
  border-radius: 2px;
  border: 1px solid var(--line-blue);
  color: var(--text-secondary);
  background: rgba(18, 41, 77, 0.5);
}

.badge--green {
  color: var(--electric-green);
  border-color: rgba(57, 255, 20, 0.4);
  background: rgba(57, 255, 20, 0.07);
}

.badge--violet {
  color: #cdb4ff;
  border-color: rgba(157, 0, 255, 0.5);
  background: rgba(157, 0, 255, 0.12);
}

.badge--warning {
  color: var(--warning);
  border-color: rgba(255, 179, 0, 0.4);
}

.pulse-dot {
  display: inline-block;
  width: 8px;
  height: 8px;
  border-radius: 50%;
  background: var(--success);
  box-shadow: 0 0 0 rgba(47, 230, 169, 0.6);
  animation: pulse 1.8s ease-out infinite;
}

@keyframes pulse {
  0% {
    box-shadow: 0 0 0 0 rgba(47, 230, 169, 0.5);
  }
  70% {
    box-shadow: 0 0 0 8px rgba(47, 230, 169, 0);
  }
  100% {
    box-shadow: 0 0 0 0 rgba(47, 230, 169, 0);
  }
}

.tag-list {
  display: flex;
  flex-wrap: wrap;
  gap: 0.5rem;
  list-style: none;
  margin: 0;
  padding: 0;
}

.tag {
  display: inline-block;
  font-family: var(--font-mono);
  font-size: 0.72rem;
  padding: 0.25rem 0.7rem;
  border: 1px solid var(--line-blue);
  border-radius: 999px;
  color: var(--text-secondary);
  background: rgba(18, 41, 77, 0.4);
}

/* ---------- 21. 返回顶部 ---------- */
.back-to-top {
  position: fixed;
  right: 1.25rem;
  bottom: 1.25rem;
  z-index: 90;
  display: inline-flex;
  align-items: center;
  gap: 0.45rem;
  min-height: 42px;
  padding: 0.5rem 0.85rem;
  font-family: var(--font-mono);
  font-size: 0.72rem;
  letter-spacing: 0.06em;
  color: var(--electric-green);
  background: rgba(18, 41, 77, 0.92);
  border: 1px solid rgba(57, 255, 20, 0.45);
  border-radius: 4px;
  cursor: pointer;
  backdrop-filter: blur(8px);
  -webkit-backdrop-filter: blur(8px);
  box-shadow: 0 10px 30px rgba(0, 0, 0, 0.4);
  transition: background-color 0.18s var(--ease-out), color 0.18s var(--ease-out), transform 0.18s var(--ease-out);
}

.back-to-top:hover {
  background: var(--electric-green);
  color: var(--deep-navy);
  transform: translateY(-2px);
}

.back-to-top__icon {
  font-size: 1rem;
  line-height: 1;
}

.back-to-top__label {
  font-size: 0.72rem;
}

/* ---------- 22. 响应式 ---------- */
@media (max-width: 1080px) {
  .grid--4 {
    grid-template-columns: repeat(2, minmax(0, 1fr));
  }

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

  .site-footer__top {
    grid-template-columns: 1fr 1fr;
    gap: 2rem;
  }

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

  .site-nav {
    position: absolute;
    top: calc(100% + 1px);
    left: 0;
    right: 0;
    display: none;
    padding: 0.85rem 1.25rem 1.25rem;
    background: rgba(11, 29, 58, 0.98);
    border-bottom: 1px solid var(--line-blue);
    box-shadow: 0 28px 56px rgba(0, 0, 0, 0.45);
  }

  .site-nav[data-open] {
    display: block;
  }

  .site-nav__list {
    flex-direction: column;
    align-items: stretch;
    gap: 0.45rem;
  }

  .site-nav__link {
    width: 100%;
    padding: 0.8rem 1rem;
    font-size: 0.95rem;
    background: rgba(18, 41, 77, 0.45);
    border-color: var(--line-blue);
  }

  .site-nav__link[aria-current="page"] {
    background: rgba(57, 255, 20, 0.08);
  }

  .site-nav__link[aria-current="page"]::after {
    display: none;
  }
}

@media (max-width: 640px) {
  .container {
    width: min(100% - 1.25rem, var(--container-w));
  }

  .container--narrow {
    width: min(100% - 1.25rem, 920px);
  }

  .site-header__inner {
    width: min(100% - 1rem, 1400px);
    gap: 0.75rem;
  }

  .site-brand__name {
    font-size: 1.1rem;
  }

  .site-brand__mark {
    width: 36px;
    height: 36px;
  }

  .site-brand__version {
    display: none;
  }

  .btn--header {
    display: none;
  }

  .site-footer__top {
    grid-template-columns: 1fr;
    gap: 1.5rem;
    padding: 2.25rem 0 1.5rem;
  }

  .site-footer__bottom {
    flex-direction: column;
    align-items: flex-start;
    gap: 0.65rem;
  }

  .grid--2,
  .grid--3,
  .grid--4 {
    grid-template-columns: 1fr;
  }

  .back-to-top {
    right: 1rem;
    bottom: 1rem;
    width: 44px;
    height: 44px;
    justify-content: center;
    padding: 0;
  }

  .back-to-top__label {
    display: none;
  }
}

/* ---------- 23. 无障碍与减弱动效 ---------- */
@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;
  }

  .btn:hover,
  .card:hover,
  .back-to-top:hover {
    transform: none;
  }

  .media-frame:hover img {
    transform: none;
  }
}