/* NG体育CN - 全站共享样式 /assets/site.css */

/* ===== 1. 设计变量 ===== */
:root {
  --color-primary: #0B1B3D;
  --color-accent: #00D4FF;
  --color-cta: #FF6B1A;
  --color-status: #C6FF00;
  --color-surface: #F5F7FA;
  --color-ink: #1A1A1A;
  --color-border: #D0D5DD;
  --color-secondary: #9B59B6;
  --color-muted: #5A6A85;
  --color-on-primary: #E8EEF9;

  --font-heading: 'Anton', 'Impact', 'Arial Narrow', 'PingFang SC', 'Microsoft YaHei', sans-serif;
  --font-body: 'Inter', 'Helvetica Neue', 'PingFang SC', 'Microsoft YaHei', 'Noto Sans SC', sans-serif;
  --font-mono: 'SF Mono', 'Cascadia Code', Consolas, 'Courier New', monospace;

  --container-max: 82.5rem;
  --header-h: 4.5rem;
  --radius: 0.375rem;
  --shadow-sm: 0 2px 8px rgba(11, 27, 61, 0.08);
  --shadow-md: 0 6px 24px rgba(11, 27, 61, 0.14);
}

/* ===== 2. Reset 与基础排版 ===== */
*,
*::before,
*::after {
  box-sizing: border-box;
}

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

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

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

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

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

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

body {
  font-family: var(--font-body);
  font-size: 1rem;
  line-height: 1.6;
  color: var(--color-ink);
  background: var(--color-surface);
  -webkit-font-smoothing: antialiased;
}

h1,
h2,
h3,
h4,
h5,
h6 {
  font-family: var(--font-heading);
  font-weight: 400;
  line-height: 1.15;
  letter-spacing: 0.02em;
  text-transform: uppercase;
}

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

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

/* ===== 3. 工具类 ===== */
.container {
  width: 100%;
  max-width: var(--container-max);
  margin-inline: auto;
  padding-inline: clamp(1.25rem, 4vw, 2.5rem);
}

.sr-only {
  position: absolute;
  width: 1px;
  height: 1px;
  padding: 0;
  margin: -1px;
  overflow: hidden;
  clip: rect(0 0 0 0);
  white-space: nowrap;
  border: 0;
}

.grid-overlay {
  position: relative;
  background-image:
    linear-gradient(rgba(0, 212, 255, 0.06) 1px, transparent 1px),
    linear-gradient(90deg, rgba(0, 212, 255, 0.06) 1px, transparent 1px);
  background-size: 28px 28px;
}

/* ===== 4. 焦点与跳过链接 ===== */
.skip-link {
  position: fixed;
  top: 0;
  left: 1rem;
  z-index: 3000;
  transform: translateY(-120%);
  background: var(--color-accent);
  color: var(--color-primary);
  font-weight: 700;
  font-size: 0.9375rem;
  padding: 0.75rem 1.5rem;
  border-radius: 0 0 var(--radius) var(--radius);
  transition: transform 0.2s ease;
}

.skip-link:focus {
  transform: translateY(0);
}

/* ===== 5. 滚动进度条 ===== */
.site-progress {
  position: fixed;
  top: 0;
  left: 0;
  z-index: 2001;
  width: 0;
  height: 3px;
  background: linear-gradient(90deg, var(--color-accent), var(--color-status));
  pointer-events: none;
}

/* ===== 6. 站点头部 ===== */
.site-header {
  position: sticky;
  top: 0;
  z-index: 1000;
  background: rgba(11, 27, 61, 0.78);
  -webkit-backdrop-filter: blur(14px);
  backdrop-filter: blur(14px);
  border-bottom: 1px solid rgba(0, 212, 255, 0.16);
  transition: background 0.3s ease, box-shadow 0.3s ease, border-color 0.3s ease;
}

.site-header[data-scrolled="true"] {
  background: rgba(11, 27, 61, 0.97);
  border-bottom-color: rgba(0, 212, 255, 0.28);
  box-shadow: 0 8px 32px rgba(3, 8, 24, 0.45);
}

.site-header__inner {
  display: flex;
  align-items: center;
  gap: 1rem;
  min-height: var(--header-h);
}

/* ===== 7. 品牌标识 ===== */
.site-logo {
  display: inline-flex;
  align-items: center;
  gap: 0.625rem;
  flex-shrink: 0;
}

.site-logo__mark {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  width: 2.5rem;
  height: 2.5rem;
  background: var(--color-primary);
  border: 2px solid var(--color-accent);
  color: var(--color-status);
  font-family: var(--font-heading);
  font-size: 1.375rem;
  line-height: 1;
  letter-spacing: 0.02em;
  border-radius: 0.25rem;
  transition: background 0.25s ease, box-shadow 0.25s ease;
}

.site-logo:hover .site-logo__mark {
  background: rgba(0, 212, 255, 0.12);
  box-shadow: 0 0 16px rgba(0, 212, 255, 0.35);
}

.site-logo__text {
  font-family: var(--font-heading);
  font-size: 1.375rem;
  line-height: 1;
  letter-spacing: 0.04em;
  color: var(--color-on-primary);
}

/* ===== 8. 导航（移动优先） ===== */
.site-nav {
  position: absolute;
  top: 100%;
  left: 0;
  right: 0;
  z-index: 50;
  display: block;
  max-height: calc(100vh - var(--header-h));
  overflow-y: auto;
  background: #0D1E44;
  border-bottom: 1px solid rgba(0, 212, 255, 0.22);
  box-shadow: 0 24px 40px rgba(2, 8, 24, 0.5);
  padding: 1rem clamp(1.25rem, 4vw, 2.5rem) 1.5rem;
  opacity: 0;
  visibility: hidden;
  transform: translateY(-10px);
  transition: opacity 0.25s ease, transform 0.25s ease, visibility 0.25s;
}

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

.site-nav__list {
  display: flex;
  flex-direction: column;
  align-items: stretch;
  gap: 0.125rem;
}

.site-nav__item {
  list-style: none;
}

.site-nav__link {
  position: relative;
  display: block;
  padding: 0.75rem 0.875rem;
  font-size: 0.9375rem;
  font-weight: 500;
  color: rgba(232, 238, 249, 0.82);
  border-left: 2px solid transparent;
  border-radius: 0 var(--radius) var(--radius) 0;
  transition: background 0.2s ease, color 0.2s ease, border-color 0.2s ease;
}

.site-nav__link:hover {
  background: rgba(0, 212, 255, 0.08);
  color: var(--color-on-primary);
}

.site-nav__link[aria-current="page"] {
  border-left-color: var(--color-accent);
  background: rgba(0, 212, 255, 0.12);
  color: var(--color-status);
}

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

/* ===== 9. 联赛切换器 ===== */
.league-switcher {
  position: relative;
  display: flex;
  align-items: center;
  gap: 0.5rem;
  margin-top: 1rem;
  padding-top: 1rem;
  border-top: 1px solid rgba(0, 212, 255, 0.16);
}

.league-switcher__label {
  font-size: 0.75rem;
  font-weight: 700;
  text-transform: uppercase;
  letter-spacing: 0.12em;
  color: rgba(232, 238, 249, 0.5);
}

.league-switcher__toggle {
  display: inline-flex;
  align-items: center;
  gap: 0.375rem;
  padding: 0.375rem 0.75rem;
  border: 1px solid rgba(0, 212, 255, 0.35);
  border-radius: 999px;
  background: rgba(0, 212, 255, 0.08);
  color: var(--color-accent);
  font-size: 0.875rem;
  font-weight: 600;
  transition: border-color 0.2s ease, background 0.2s ease, box-shadow 0.2s ease;
}

.league-switcher__toggle:hover,
.league-switcher__toggle[aria-expanded="true"] {
  border-color: var(--color-accent);
  background: rgba(0, 212, 255, 0.16);
  box-shadow: 0 0 0 3px rgba(0, 212, 255, 0.14);
}

.league-switcher__current {
  display: inline-block;
  line-height: 1.2;
}

.league-switcher__arrow {
  font-size: 0.625rem;
  transition: transform 0.2s ease;
}

.league-switcher__toggle[aria-expanded="true"] .league-switcher__arrow {
  transform: rotate(180deg);
}

.league-switcher__menu {
  position: absolute;
  top: calc(100% + 0.5rem);
  left: 0;
  min-width: 8rem;
  background: #0F2248;
  border: 1px solid rgba(0, 212, 255, 0.24);
  border-radius: var(--radius);
  box-shadow: 0 12px 32px rgba(2, 6, 20, 0.5);
  padding: 0.25rem;
  opacity: 0;
  visibility: hidden;
  transform: translateY(6px);
  transition: opacity 0.2s ease, transform 0.2s ease, visibility 0.2s;
  z-index: 50;
}

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

.league-switcher__option {
  display: block;
  width: 100%;
  text-align: left;
  padding: 0.5rem 0.875rem;
  font-size: 0.875rem;
  color: var(--color-on-primary);
  border-radius: calc(var(--radius) - 2px);
  transition: background 0.2s ease, color 0.2s ease;
}

.league-switcher__option:hover {
  background: rgba(0, 212, 255, 0.14);
  color: var(--color-status);
}

/* ===== 10. 移动导航按钮 ===== */
.site-nav__toggle {
  display: inline-flex;
  flex-direction: column;
  justify-content: center;
  gap: 5px;
  width: 2.75rem;
  height: 2.75rem;
  padding: 0.625rem;
  margin-left: auto;
  border-radius: var(--radius);
  border: 1px solid rgba(0, 212, 255, 0.3);
  background: rgba(0, 212, 255, 0.06);
  flex-shrink: 0;
}

.site-nav__toggle-bar {
  display: block;
  height: 2px;
  width: 100%;
  background: var(--color-accent);
  border-radius: 2px;
  transition: transform 0.25s ease, opacity 0.25s ease;
}

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

.site-nav__toggle[aria-expanded="true"] .site-nav__toggle-bar:nth-child(2) {
  opacity: 0;
}

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

/* ===== 11. 按钮 ===== */
.btn {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  gap: 0.5rem;
  padding: 0.75rem 1.5rem;
  font-family: var(--font-body);
  font-size: 0.9375rem;
  font-weight: 600;
  line-height: 1.2;
  letter-spacing: 0.02em;
  border-radius: var(--radius);
  border: 1.5px solid transparent;
  white-space: nowrap;
  cursor: pointer;
  transition: background-color 0.2s ease, color 0.2s ease, border-color 0.2s ease, transform 0.2s ease, box-shadow 0.2s ease;
}

.btn--primary {
  background: var(--color-cta);
  color: #FFFFFF;
  box-shadow: 0 4px 16px rgba(255, 107, 26, 0.28);
}

.btn--primary:hover {
  background: #E85A0E;
  box-shadow: 0 6px 24px rgba(255, 107, 26, 0.38);
  transform: translateY(-1px);
}

.btn--outline {
  border-color: var(--color-accent);
  color: var(--color-accent);
  background: transparent;
}

.btn--outline:hover {
  background: rgba(0, 212, 255, 0.12);
  box-shadow: 0 0 0 3px rgba(0, 212, 255, 0.16);
}

.btn--ghost {
  border-color: rgba(245, 247, 250, 0.35);
  color: var(--color-on-primary);
  background: transparent;
}

.btn--ghost:hover {
  border-color: var(--color-on-primary);
  background: rgba(245, 247, 250, 0.1);
}

/* ===== 12. 章节与标题 ===== */
.section {
  padding-block: clamp(3rem, 7vw, 6.5rem);
}

.section--dark {
  background: var(--color-primary);
  color: var(--color-on-primary);
}

.section--light {
  background: var(--color-surface);
}

.section-head {
  max-width: 48rem;
  margin-bottom: 2.5rem;
}

.section-label {
  display: inline-flex;
  align-items: center;
  gap: 0.625rem;
  font-size: 0.8125rem;
  font-weight: 700;
  letter-spacing: 0.16em;
  text-transform: uppercase;
  color: var(--color-accent);
}

.section-label::before {
  content: "";
  width: 2rem;
  height: 2px;
  background: var(--color-accent);
  flex-shrink: 0;
}

.section-label--orange {
  color: var(--color-cta);
}

.section-label--orange::before {
  background: var(--color-cta);
}

.section--dark .section-label {
  color: var(--color-status);
}

.section--dark .section-label::before {
  background: var(--color-status);
}

.section-title {
  margin-top: 0.75rem;
  font-size: clamp(1.75rem, 4.5vw, 3rem);
  letter-spacing: 0.01em;
}

.section--dark .section-title {
  color: #FFFFFF;
}

.section-desc {
  margin-top: 0.875rem;
  font-size: 1.0625rem;
  line-height: 1.7;
  color: var(--color-muted);
}

.section--dark .section-desc {
  color: #9FB0D0;
}

/* ===== 13. 首屏章节预览与页面首屏 ===== */
.chapter-preview {
  display: grid;
  grid-template-columns: minmax(0, 1.2fr) minmax(0, 0.8fr);
  gap: clamp(1.5rem, 4vw, 3.5rem);
  align-items: center;
  min-height: calc(100vh - var(--header-h));
  padding-block: clamp(3rem, 8vw, 5rem);
  background: var(--color-primary);
  color: var(--color-on-primary);
}

.chapter-preview__body {
  max-width: 42rem;
}

.chapter-preview__desc {
  margin-top: 1.5rem;
  font-size: 1.125rem;
  line-height: 1.7;
  color: #9FB0D0;
  max-width: 34rem;
}

.chapter-preview__list {
  margin-top: 2rem;
  display: grid;
  gap: 0.75rem;
  counter-reset: chapter;
}

.chapter-preview__item {
  counter-increment: chapter;
  display: flex;
  align-items: baseline;
  gap: 1rem;
  padding: 1rem 1.25rem;
  background: rgba(255, 255, 255, 0.03);
  border: 1px solid rgba(0, 212, 255, 0.16);
  border-radius: var(--radius);
  transition: border-color 0.25s ease, background 0.25s ease, transform 0.25s ease;
}

.chapter-preview__item::before {
  content: counter(chapter, decimal-leading-zero);
  font-family: var(--font-heading);
  font-size: 1.25rem;
  color: var(--color-cta);
  flex-shrink: 0;
}

.chapter-preview__item:hover {
  border-color: var(--color-accent);
  background: rgba(0, 212, 255, 0.07);
  transform: translateX(4px);
}

.chapter-preview__link {
  font-family: var(--font-heading);
  font-size: 1.125rem;
  letter-spacing: 0.02em;
  color: var(--color-on-primary);
  transition: color 0.2s ease;
}

.chapter-preview__link:hover {
  color: var(--color-status);
}

.chapter-preview__aside {
  position: relative;
  padding: 1.5rem;
  border: 1px solid rgba(0, 212, 255, 0.2);
  border-radius: var(--radius);
  background: rgba(0, 212, 255, 0.04);
}

.page-hero {
  position: relative;
  background: var(--color-primary);
  color: var(--color-on-primary);
  padding-block: clamp(3rem, 8vw, 5.5rem) clamp(2.5rem, 6vw, 4rem);
  border-bottom: 1px solid rgba(0, 212, 255, 0.18);
  overflow: hidden;
}

.page-hero::before {
  content: "";
  position: absolute;
  inset: 0;
  background:
    radial-gradient(ellipse at 85% 20%, rgba(155, 89, 182, 0.22), transparent 60%),
    linear-gradient(rgba(0, 212, 255, 0.05) 1px, transparent 1px),
    linear-gradient(90deg, rgba(0, 212, 255, 0.05) 1px, transparent 1px);
  background-size: auto, 28px 28px, 28px 28px;
  pointer-events: none;
}

.page-hero__container {
  position: relative;
  z-index: 1;
}

.page-hero__title {
  margin-top: 0.75rem;
  font-size: clamp(2rem, 5vw, 3.25rem);
  color: #FFFFFF;
}

.page-hero__desc {
  margin-top: 0.875rem;
  font-size: 1.0625rem;
  max-width: 40rem;
  color: #9FB0D0;
}

.page-hero .breadcrumb {
  color: #8CA0C3;
}

.page-hero .breadcrumb a {
  color: var(--color-accent);
}

.page-hero .breadcrumb .breadcrumb__sep {
  color: #5A6A85;
}

/* ===== 14. 面包屑 ===== */
.breadcrumb {
  display: flex;
  flex-wrap: wrap;
  align-items: center;
  gap: 0.5rem;
  font-size: 0.875rem;
  color: var(--color-muted);
  padding-block: 1.25rem 0;
}

.breadcrumb a {
  color: var(--color-accent);
  transition: color 0.2s ease;
}

.breadcrumb a:hover {
  color: var(--color-cta);
}

.breadcrumb__sep {
  color: var(--color-border);
}

/* ===== 15. 卡片 ===== */
.card {
  display: flex;
  flex-direction: column;
  background: #FFFFFF;
  border: 1px solid var(--color-border);
  border-radius: var(--radius);
  overflow: hidden;
  transition: border-color 0.25s ease, box-shadow 0.25s ease, transform 0.25s ease;
}

.card:hover {
  border-color: var(--color-accent);
  box-shadow: var(--shadow-md);
  transform: translateY(-2px);
}

.card__body {
  display: flex;
  flex-direction: column;
  gap: 0.625rem;
  padding: 1.5rem;
  flex: 1;
}

.card__title {
  font-family: var(--font-heading);
  font-size: 1.375rem;
  line-height: 1.2;
  color: var(--color-primary);
}

.card__text {
  font-size: 0.9375rem;
  color: var(--color-muted);
  line-height: 1.6;
}

.card--compact .card__body {
  padding: 1rem;
}

.card--compact .card__title {
  font-size: 1.125rem;
}

/* ===== 16. 标签与状态 ===== */
.tag {
  display: inline-flex;
  align-items: center;
  gap: 0.4rem;
  padding: 0.25rem 0.625rem;
  font-size: 0.75rem;
  font-weight: 600;
  letter-spacing: 0.06em;
  border-radius: 999px;
  background: rgba(0, 212, 255, 0.14);
  border: 1px solid rgba(0, 212, 255, 0.4);
  color: var(--color-primary);
}

.tag--live {
  background: var(--color-status);
  border-color: #A8E000;
  color: #1A2610;
}

.tag--dark {
  background: rgba(0, 212, 255, 0.16);
  border-color: rgba(0, 212, 255, 0.4);
  color: var(--color-accent);
}

.status-dot {
  display: inline-block;
  width: 0.5rem;
  height: 0.5rem;
  border-radius: 50%;
  background: var(--color-status);
  animation: pulse 1.6s ease-in-out infinite;
}

@keyframes pulse {
  0%,
  100% {
    box-shadow: 0 0 0 0 rgba(198, 255, 0, 0.5);
  }
  50% {
    box-shadow: 0 0 0 5px rgba(198, 255, 0, 0);
  }
}

/* ===== 17. 图片框架 ===== */
.img-frame {
  position: relative;
  display: block;
  width: 100%;
  overflow: hidden;
  background: var(--color-primary);
}

.img-frame--16x9 {
  aspect-ratio: 16 / 9;
}

.img-frame--4x3 {
  aspect-ratio: 4 / 3;
}

.img-frame--square {
  aspect-ratio: 1 / 1;
}

.img-frame--portrait {
  aspect-ratio: 3 / 4;
}

.img-frame__placeholder {
  position: absolute;
  inset: 0;
  display: flex;
  align-items: center;
  justify-content: center;
  background:
    linear-gradient(135deg, rgba(0, 212, 255, 0.12) 25%, transparent 25%) 0 0 / 24px 24px,
    linear-gradient(315deg, rgba(0, 212, 255, 0.08) 25%, transparent 25%) 0 0 / 24px 24px,
    var(--color-primary);
  color: var(--color-accent);
  font-size: 0.8125rem;
  letter-spacing: 0.16em;
  text-transform: uppercase;
}

.img-frame img {
  position: absolute;
  inset: 0;
  width: 100%;
  height: 100%;
  object-fit: cover;
}

/* ===== 18. 数据组件 ===== */
.table-wrap {
  width: 100%;
  overflow-x: auto;
  border: 1px solid var(--color-border);
  border-radius: var(--radius);
  background: #FFFFFF;
}

.table-wrap table {
  width: 100%;
  border-collapse: collapse;
  min-width: 40rem;
  font-size: 0.9375rem;
}

.table-wrap th,
.table-wrap td {
  padding: 0.75rem 1rem;
  text-align: left;
  border-bottom: 1px solid var(--color-border);
  white-space: nowrap;
}

.table-wrap th {
  background: var(--color-primary);
  color: var(--color-on-primary);
  font-size: 0.8125rem;
  font-weight: 600;
  text-transform: uppercase;
  letter-spacing: 0.08em;
}

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

.table-wrap tbody tr {
  transition: background 0.15s ease;
}

.table-wrap tbody tr:hover {
  background: rgba(0, 212, 255, 0.07);
}

.stat-grid {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(10rem, 1fr));
  gap: 1rem;
}

.stat-item {
  display: flex;
  flex-direction: column;
  gap: 0.25rem;
  padding: 1.25rem;
  background: #FFFFFF;
  border: 1px solid var(--color-border);
  border-left: 3px solid var(--color-accent);
  border-radius: var(--radius);
}

.stat-item__num {
  font-family: var(--font-heading);
  font-size: 2rem;
  color: var(--color-primary);
}

.stat-item__label {
  font-size: 0.8125rem;
  color: var(--color-muted);
  text-transform: uppercase;
  letter-spacing: 0.08em;
}

/* ===== 19. 图例、坐标、旁注与延伸入口 ===== */
.legend {
  display: flex;
  flex-wrap: wrap;
  gap: 0.5rem 1.25rem;
}

.legend__item {
  display: inline-flex;
  align-items: center;
  gap: 0.4rem;
  font-size: 0.875rem;
  color: var(--color-muted);
}

.legend__swatch {
  width: 0.6rem;
  height: 0.6rem;
  border-radius: 2px;
  background: var(--color-accent);
}

.coordinate {
  font-family: var(--font-mono);
  font-size: 0.8125rem;
  letter-spacing: 0.05em;
  color: var(--color-accent);
}

.aside-note {
  border-left: 3px solid var(--color-accent);
  background: rgba(0, 212, 255, 0.06);
  padding: 1rem 1.25rem;
  font-size: 0.925rem;
  line-height: 1.7;
  color: var(--color-muted);
}

.entry-link {
  display: inline-flex;
  align-items: center;
  gap: 0.5rem;
  font-weight: 600;
  color: var(--color-accent);
  transition: gap 0.25s ease, color 0.25s ease;
}

.entry-link::after {
  content: "→";
  transition: transform 0.25s ease;
}

.entry-link:hover {
  color: var(--color-cta);
  gap: 0.75rem;
}

/* ===== 20. 滚动显现 ===== */
.reveal,
[data-reveal] {
  opacity: 0;
  transform: translateY(28px);
  transition: opacity 0.65s ease, transform 0.65s ease;
}

.reveal[data-visible="true"],
[data-reveal][data-visible="true"] {
  opacity: 1;
  transform: none;
}

/* ===== 21. 页脚 ===== */
.site-footer {
  position: relative;
  background: #08122E;
  color: #98A8C8;
  overflow: hidden;
}

.site-footer__glow {
  height: 3px;
  background: linear-gradient(90deg, var(--color-accent) 0%, var(--color-secondary) 45%, var(--color-status) 100%);
}

.site-footer__top {
  display: grid;
  grid-template-columns: minmax(0, 1.6fr) minmax(0, 1fr) minmax(0, 1fr) minmax(0, 1.3fr);
  gap: 2.5rem;
  padding-top: 3.5rem;
  padding-bottom: 3rem;
}

.site-footer__brand {
  display: flex;
  flex-direction: column;
  align-items: flex-start;
}

.site-footer__logo .site-logo__mark {
  background: transparent;
}

.site-footer__slogan {
  margin-top: 1rem;
  font-family: var(--font-heading);
  font-size: 1.125rem;
  letter-spacing: 0.03em;
  color: var(--color-accent);
}

.site-footer__trust {
  margin-top: 0.875rem;
  max-width: 22rem;
  font-size: 0.875rem;
  line-height: 1.7;
  color: #7E8FB0;
}

.site-footer__nav,
.site-footer__meta,
.site-footer__contact {
  min-width: 0;
}

.site-footer__heading {
  display: flex;
  align-items: center;
  gap: 0.625rem;
  margin-bottom: 1.125rem;
  font-family: var(--font-body);
  font-size: 0.8125rem;
  font-weight: 700;
  letter-spacing: 0.14em;
  text-transform: uppercase;
  color: var(--color-on-primary);
}

.site-footer__heading::before {
  content: "";
  width: 1.5rem;
  height: 2px;
  background: var(--color-accent);
  flex-shrink: 0;
}

.site-footer__link-list {
  display: flex;
  flex-direction: column;
  gap: 0.5rem;
}

.site-footer__link-list a {
  display: inline-block;
  font-size: 0.9375rem;
  color: #98A8C8;
  transition: color 0.2s ease, transform 0.2s ease;
}

.site-footer__link-list a:hover {
  color: var(--color-status);
  transform: translateX(3px);
}

.site-footer__contact-list {
  display: flex;
  flex-direction: column;
  gap: 0.625rem;
}

.site-footer__contact-item {
  display: flex;
  flex-direction: column;
  gap: 0.125rem;
}

.site-footer__contact-label {
  font-size: 0.75rem;
  font-weight: 700;
  letter-spacing: 0.08em;
  text-transform: uppercase;
  color: #5E7093;
}

.site-footer__contact-value {
  font-size: 0.9375rem;
  color: var(--color-on-primary);
}

.site-footer__bottom {
  display: flex;
  flex-wrap: wrap;
  align-items: center;
  justify-content: space-between;
  gap: 0.75rem 1.5rem;
  padding-block: 1.5rem;
  border-top: 1px solid rgba(0, 212, 255, 0.12);
  font-size: 0.8125rem;
  color: #6E80A3;
}

.site-footer__icp {
  letter-spacing: 0.02em;
}

/* ===== 22. 返回顶部 ===== */
.back-to-top {
  position: fixed;
  right: 1.5rem;
  bottom: 1.5rem;
  z-index: 900;
  display: inline-flex;
  align-items: center;
  justify-content: center;
  width: 3rem;
  height: 3rem;
  border-radius: 50%;
  background: var(--color-primary);
  border: 1.5px solid var(--color-accent);
  color: var(--color-accent);
  box-shadow: 0 8px 24px rgba(3, 8, 24, 0.4);
  opacity: 0;
  visibility: hidden;
  transform: translateY(12px);
  transition: opacity 0.25s ease, transform 0.25s ease, visibility 0.25s, background 0.2s ease, color 0.2s ease;
}

.back-to-top[data-visible="true"] {
  opacity: 1;
  visibility: visible;
  transform: none;
}

.back-to-top:hover {
  background: var(--color-accent);
  color: var(--color-primary);
}

.back-to-top__icon {
  line-height: 1;
  font-size: 1.25rem;
}

/* ===== 23. 桌面断点 ===== */
@media (min-width: 992px) {
  .site-nav {
    position: static;
    display: flex;
    align-items: center;
    gap: 2rem;
    max-height: none;
    overflow-y: visible;
    margin-left: auto;
    background: transparent;
    border: 0;
    box-shadow: none;
    padding: 0;
    opacity: 1;
    visibility: visible;
    transform: none;
  }

  .site-nav__list {
    flex-direction: row;
    gap: 0.25rem;
  }

  .site-nav__link {
    padding: 0.625rem 0.875rem;
    border-left: 0;
    border-radius: var(--radius);
    color: rgba(232, 238, 249, 0.78);
  }

  .site-nav__link:hover {
    background: transparent;
    color: var(--color-on-primary);
  }

  .site-nav__link[aria-current="page"] {
    border-left-color: transparent;
    background: rgba(0, 212, 255, 0.08);
    color: var(--color-status);
  }

  .site-nav__link::after {
    display: block;
    content: "";
    position: absolute;
    left: 0.875rem;
    right: 0.875rem;
    bottom: 0.125rem;
    height: 2px;
    background: var(--color-accent);
    transform: scaleX(0);
    transform-origin: left center;
    transition: transform 0.25s ease;
  }

  .site-nav__link:hover::after,
  .site-nav__link[aria-current="page"]::after {
    transform: scaleX(1);
  }

  .site-nav__toggle {
    display: none;
  }

  .league-switcher {
    margin-top: 0;
    margin-left: 0.5rem;
    padding-top: 0;
    border-top: 0;
    border-left: 1px solid rgba(0, 212, 255, 0.22);
    padding-left: 1.25rem;
  }

  .league-switcher__menu {
    left: auto;
    right: 0;
  }
}

/* ===== 24. 平板与手机优化 ===== */
@media (max-width: 1023px) {
  .site-footer__top {
    grid-template-columns: 1fr 1fr;
    gap: 2rem;
  }
}

@media (max-width: 767px) {
  .chapter-preview {
    grid-template-columns: 1fr;
    min-height: auto;
  }

  .chapter-preview__aside {
    margin-top: 0.5rem;
  }
}

@media (max-width: 639px) {
  .site-footer__top {
    grid-template-columns: 1fr;
    gap: 1.75rem;
    padding-top: 2.5rem;
  }

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

  .back-to-top {
    right: 1rem;
    bottom: 1rem;
  }
}

/* ===== 25. 动效偏好 ===== */
@media (prefers-reduced-motion: reduce) {
  html {
    scroll-behavior: auto !important;
  }

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

  .reveal,
  [data-reveal] {
    opacity: 1 !important;
    transform: none !important;
  }
}