/* ==========================================================
   欧皇体育 / Site Core CSS
   共享层：全域变量、中文排版、头部、页脚、通用基础组件
   ========================================================== */

/* ---------- 1. 变量 ---------- */
:root {
  --ink-900: #0B1622;
  --ink-800: #132333;
  --ink-600: #1E3448;
  --neon-lime: #D5FF00;
  --safety-orange: #FF6B35;
  --ice-blue: #E0F2FE;
  --muted-slate: #8CA0B3;
  --glass-white: rgba(255, 255, 255, 0.08);
  --gradient-a: linear-gradient(135deg, #0B1622 0%, #1E3448 100%);
  --gradient-b: linear-gradient(135deg, #FF6B35 0%, #D5FF00 100%);
  --font-serif: "Noto Serif SC", "Source Han Serif SC", "Songti SC", "SimSun", serif;
  --font-sans: "Noto Sans SC", "Source Han Sans SC", "PingFang SC", "Microsoft YaHei", sans-serif;
  --font-mono: "JetBrains Mono", "Roboto Mono", "SFMono-Regular", Consolas, monospace;
  --wrap: 74rem;
  --wrap-narrow: 46rem;
  --radius-sm: 6px;
  --radius-md: 12px;
  --radius-lg: 20px;
  --ease: cubic-bezier(0.22, 1, 0.36, 1);
  --transition: 0.25s var(--ease);
}

/* ---------- 2. Reset / 基础 ---------- */
*,
*::before,
*::after {
  box-sizing: border-box;
  margin: 0;
  padding: 0;
}

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

body {
  font-family: var(--font-sans);
  font-size: 1rem;
  font-weight: 400;
  line-height: 1.75;
  color: var(--ice-blue);
  background-color: var(--ink-900);
  background-image:
    radial-gradient(1000px 520px at 85% -10%, rgba(30, 52, 72, 0.55) 0%, transparent 60%),
    radial-gradient(900px 480px at 5% 110%, rgba(21, 41, 61, 0.7) 0%, transparent 55%);
  min-height: 100vh;
  -webkit-font-smoothing: antialiased;
  text-rendering: optimizeLegibility;
}

h1, h2, h3, h4 {
  font-family: var(--font-sans);
  color: var(--ice-blue);
  line-height: 1.3;
  text-wrap: balance;
}

p {
  text-wrap: pretty;
}

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

ul, ol {
  list-style: none;
}

a {
  color: var(--ice-blue);
  text-decoration-thickness: 1px;
  text-underline-offset: 0.2em;
  transition: color var(--transition);
}

a:hover {
  color: var(--neon-lime);
}

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

button {
  border: 0;
  background: none;
  cursor: pointer;
}

:focus-visible {
  outline: 2px solid var(--neon-lime);
  outline-offset: 3px;
  border-radius: 4px;
}

::selection {
  background: rgba(213, 255, 0, 0.25);
  color: #FFFFFF;
}

hr {
  border: 0;
  border-top: 1px solid rgba(224, 242, 254, 0.12);
  margin: 2rem 0;
}

code, kbd, samp {
  font-family: var(--font-mono);
  font-size: 0.9em;
}

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

th, td {
  text-align: left;
  padding: 0.6rem 0.75rem;
  border-bottom: 1px solid rgba(140, 160, 179, 0.15);
}

th {
  font-weight: 700;
  color: var(--muted-slate);
  font-size: 0.8rem;
  letter-spacing: 0.08em;
  text-transform: uppercase;
}

blockquote {
  border-left: 3px solid var(--safety-orange);
  padding-left: 1.25rem;
  margin: 1.5rem 0;
  color: var(--muted-slate);
  font-family: var(--font-serif);
}

/* ---------- 3. 工具类 ---------- */
.visually-hidden {
  position: absolute !important;
  width: 1px;
  height: 1px;
  overflow: hidden;
  clip: rect(0 0 0 0);
  clip-path: inset(50%);
  white-space: nowrap;
}

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

.skip-link {
  position: fixed;
  top: -4rem;
  left: 1rem;
  z-index: 9999;
  background: var(--neon-lime);
  color: var(--ink-900);
  font-weight: 900;
  font-size: 0.9rem;
  padding: 0.7rem 1.2rem;
  border-radius: 0 0 10px 10px;
  text-decoration: none;
  box-shadow: 0 8px 24px rgba(0, 0, 0, 0.35);
  transition: top 0.25s var(--ease);
}

.skip-link:focus-visible {
  top: 0;
  color: var(--ink-900);
}

/* ---------- 4. 头部 ---------- */
.site-header {
  position: relative;
  z-index: 50;
  background: rgba(11, 22, 34, 0.88);
  -webkit-backdrop-filter: blur(16px);
  backdrop-filter: blur(16px);
}

.site-header::after {
  content: "";
  position: absolute;
  bottom: 0;
  left: 0;
  right: 0;
  height: 2px;
  background: linear-gradient(90deg, transparent 0%, rgba(255, 107, 53, 0.55) 30%, rgba(213, 255, 0, 0.4) 70%, transparent 100%);
  pointer-events: none;
}

.header-dataline {
  max-width: var(--wrap);
  margin-inline: auto;
  padding: 0.55rem 1.5rem;
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 1rem;
  color: var(--muted-slate);
  font-size: 0.72rem;
  letter-spacing: 0.1em;
  text-transform: uppercase;
  border-bottom: 1px solid rgba(140, 160, 179, 0.12);
}

.header-dataline__item {
  display: flex;
  align-items: center;
  gap: 0.5rem;
}

.header-dataline__item--right {
  justify-content: flex-end;
}

.live-dot {
  width: 7px;
  height: 7px;
  border-radius: 50%;
  background: var(--neon-lime);
  display: inline-block;
  flex: none;
  box-shadow: 0 0 0 0 rgba(213, 255, 0, 0.45);
  animation: live-pulse 2.2s ease-out infinite;
}

@keyframes live-pulse {
  0% { box-shadow: 0 0 0 0 rgba(213, 255, 0, 0.45); }
  70% { box-shadow: 0 0 0 8px rgba(213, 255, 0, 0); }
  100% { box-shadow: 0 0 0 0 rgba(213, 255, 0, 0); }
}

.header-main {
  position: relative;
  padding: 2rem 1.5rem 1.6rem;
  text-align: center;
  overflow: hidden;
}

.header-deco {
  position: absolute;
  inset: 0;
  z-index: 0;
  pointer-events: none;
}

.header-deco__slash {
  position: absolute;
  top: 46%;
  left: 50%;
  width: min(46rem, 86%);
  height: 1px;
  background: linear-gradient(90deg, transparent 5%, rgba(255, 107, 53, 0.5) 38%, rgba(255, 107, 53, 0) 85%);
  transform: translate(-50%, -50%) rotate(-2.2deg);
}

.header-deco__slash--lime {
  top: 58%;
  background: linear-gradient(90deg, transparent 10%, rgba(213, 255, 0, 0.3) 55%, transparent 95%);
  transform: translate(-50%, -50%) rotate(1.4deg);
}

.masthead {
  position: relative;
  z-index: 1;
  display: inline-flex;
  flex-direction: column;
  align-items: center;
  gap: 0.6rem;
  text-decoration: none;
  padding: 0.75rem 1.5rem;
  border-radius: 16px;
}

.masthead:hover {
  color: inherit;
}

.masthead:hover .masthead__brand {
  color: #FFFFFF;
}

.masthead__brand {
  font-family: var(--font-sans);
  font-weight: 900;
  font-size: clamp(2.6rem, 6.5vw, 4.6rem);
  line-height: 1;
  letter-spacing: 0.05em;
  color: var(--ice-blue);
  text-shadow: 0 0 34px rgba(213, 255, 0, 0.12);
  transition: color 0.25s var(--ease);
}

.masthead__tagline {
  font-family: var(--font-sans);
  font-weight: 900;
  font-size: 0.8rem;
  letter-spacing: 0.6em;
  padding-left: 0.6em;
  color: var(--neon-lime);
  text-transform: uppercase;
  position: relative;
  display: inline-block;
}

.masthead__tagline::before,
.masthead__tagline::after {
  content: "";
  position: absolute;
  top: 50%;
  width: 1rem;
  height: 2px;
  background: var(--safety-orange);
  transform: rotate(-20deg);
}

.masthead__tagline::before {
  left: -1.4rem;
}

.masthead__tagline::after {
  right: -1.4rem;
  transform: rotate(20deg);
}

/* ---------- 5. 导航 ---------- */
.header-navbar {
  position: relative;
  min-height: 3.75rem;
  display: flex;
  align-items: center;
  justify-content: center;
  background: rgba(19, 35, 51, 0.45);
}

.header-nav {
  display: block;
}

.nav-list {
  display: flex;
  align-items: center;
  justify-content: center;
  flex-wrap: wrap;
  gap: 0.25rem;
  padding: 0.5rem 1rem;
}

.nav-item {
  margin: 0;
}

.nav-link {
  display: block;
  padding: 0.7rem 1rem;
  border-radius: 8px;
  font-family: var(--font-sans);
  font-weight: 700;
  font-size: 0.92rem;
  letter-spacing: 0.05em;
  color: var(--ice-blue);
  text-decoration: none;
  box-shadow: inset 0 -2px 0 transparent;
  transition: color 0.2s var(--ease), background 0.2s var(--ease), box-shadow 0.2s var(--ease);
}

.nav-link:hover {
  color: var(--neon-lime);
  background: var(--glass-white);
}

.nav-link[aria-current="page"] {
  color: var(--neon-lime);
  background: linear-gradient(180deg, transparent, rgba(213, 255, 0, 0.07));
  box-shadow: inset 0 -2px 0 var(--neon-lime);
}

.nav-toggle {
  display: none;
  width: 44px;
  height: 44px;
  flex-direction: column;
  align-items: center;
  justify-content: center;
  border: 1px solid rgba(224, 242, 254, 0.16);
  border-radius: 10px;
  background: rgba(11, 22, 34, 0.5);
  transition: border-color 0.2s, background 0.2s;
}

.nav-toggle:hover {
  border-color: rgba(213, 255, 0, 0.4);
  background: rgba(11, 22, 34, 0.8);
}

.nav-toggle__icon {
  display: flex;
  flex-direction: column;
  gap: 5px;
  width: 22px;
}

.nav-toggle__bar {
  display: block;
  height: 2px;
  width: 100%;
  background: var(--ice-blue);
  border-radius: 2px;
  transition: transform 0.3s var(--ease), opacity 0.2s;
}

.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);
}

/* ---------- 6. 页脚 ---------- */
.site-footer {
  position: relative;
  margin-top: 5rem;
  background: linear-gradient(180deg, var(--ink-900) 0%, var(--ink-800) 100%);
}

.footer-accent {
  position: absolute;
  top: -1px;
  left: 0;
  height: 3px;
  width: 100%;
  background: linear-gradient(90deg, var(--safety-orange) 0%, var(--neon-lime) 100%);
  opacity: 0.65;
}

.footer-grid {
  display: grid;
  grid-template-columns: 1.8fr 1fr 0.9fr 1.3fr;
  gap: 2.5rem;
  padding-top: 3rem;
  padding-bottom: 2.5rem;
}

.footer-brand__name {
  font-family: var(--font-sans);
  font-weight: 900;
  font-size: 2rem;
  letter-spacing: 0.08em;
  line-height: 1.2;
  color: var(--ice-blue);
}

.footer-brand__slogan {
  font-family: var(--font-sans);
  font-weight: 900;
  font-size: 0.8rem;
  letter-spacing: 0.5em;
  color: var(--neon-lime);
  margin-top: 0.3rem;
  margin-bottom: 1rem;
  text-transform: uppercase;
}

.footer-brand__brief {
  color: var(--muted-slate);
  font-size: 0.88rem;
  line-height: 1.8;
  max-width: 30rem;
}

.footer-brand__link {
  margin-top: 1.2rem;
}

.footer-col {
  display: block;
}

.footer-head {
  font-family: var(--font-sans);
  font-weight: 900;
  font-size: 0.8rem;
  letter-spacing: 0.18em;
  color: var(--muted-slate);
  margin-bottom: 1rem;
  padding-bottom: 0.55rem;
  border-bottom: 1px solid rgba(213, 255, 0, 0.18);
  text-transform: uppercase;
}

.footer-links {
  display: grid;
  gap: 0.45rem;
}

.footer-links a {
  display: inline-flex;
  align-items: center;
  gap: 0.45rem;
  color: var(--ice-blue);
  font-size: 0.92rem;
  text-decoration: none;
  transition: color 0.2s, transform 0.2s;
}

.footer-links a::before {
  content: "›";
  color: var(--safety-orange);
  font-family: var(--font-mono);
  font-size: 1rem;
  line-height: 1;
  transition: color 0.2s, transform 0.2s;
}

.footer-links a:hover {
  color: var(--neon-lime);
  transform: translateX(3px);
}

.footer-links a:hover::before {
  color: var(--neon-lime);
}

.footer-contact {
  display: grid;
  align-content: start;
  gap: 0.4rem;
}

.footer-contact__line {
  display: flex;
  flex-wrap: wrap;
  gap: 0.5rem;
  font-family: var(--font-mono);
  font-size: 0.8rem;
  color: var(--muted-slate);
  padding: 0.4rem 0;
  border-bottom: 1px dashed rgba(140, 160, 179, 0.14);
}

.footer-contact__label {
  flex: none;
  color: var(--ice-blue);
  font-family: var(--font-sans);
  font-weight: 700;
  font-size: 0.75rem;
  letter-spacing: 0.1em;
  text-transform: uppercase;
}

.footer-contact__link {
  display: inline-block;
  margin-top: 0.8rem;
  font-weight: 700;
  font-size: 0.85rem;
  color: var(--neon-lime);
  text-decoration: none;
}

.footer-contact__link::after {
  content: " →";
  font-family: var(--font-mono);
}

.footer-bottom {
  border-top: 1px solid rgba(224, 242, 254, 0.07);
  background: rgba(11, 22, 34, 0.9);
  padding: 1.2rem 0;
}

.footer-bottom__inner {
  display: flex;
  flex-direction: column;
  gap: 0.7rem;
}

.footer-bottom__trust {
  font-size: 0.78rem;
  line-height: 1.7;
  color: var(--muted-slate);
  max-width: 58rem;
  opacity: 0.8;
}

.footer-bottom__meta {
  display: flex;
  flex-wrap: wrap;
  justify-content: space-between;
  gap: 0.5rem;
  color: var(--muted-slate);
  font-family: var(--font-mono);
  font-size: 0.76rem;
}

/* ---------- 7. 容器 ---------- */
.wrap {
  width: min(100% - 2.5rem, var(--wrap));
  margin-inline: auto;
}

.wrap--narrow {
  width: min(100% - 2.5rem, var(--wrap-narrow));
}

/* ---------- 8. 通用网格 ---------- */
.grid {
  display: grid;
  gap: 1.5rem;
}

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

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

/* ---------- 9. 按钮 ---------- */
.btn {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  gap: 0.5rem;
  font-family: var(--font-sans);
  font-weight: 800;
  font-size: 0.92rem;
  line-height: 1;
  padding: 0.8rem 1.5rem;
  border-radius: 999px;
  text-decoration: none;
  border: 1px solid transparent;
  transition: transform 0.25s var(--ease), box-shadow 0.25s, background 0.25s, color 0.25s;
}

.btn:hover {
  transform: translateY(-2px);
  text-decoration: none;
}

.btn--primary {
  background: var(--gradient-b);
  color: var(--ink-900);
  box-shadow: 0 8px 24px rgba(255, 107, 53, 0.28);
}

.btn--primary:hover {
  color: var(--ink-900);
  box-shadow: 0 12px 32px rgba(213, 255, 0, 0.22);
}

.btn--ghost {
  background: var(--glass-white);
  color: var(--ice-blue);
  border-color: rgba(224, 242, 254, 0.18);
  -webkit-backdrop-filter: blur(8px);
  backdrop-filter: blur(8px);
}

.btn--ghost:hover {
  color: var(--neon-lime);
  border-color: rgba(213, 255, 0, 0.4);
}

/* ---------- 10. 面包屑 ---------- */
.breadcrumbs {
  display: flex;
  flex-wrap: wrap;
  align-items: center;
  gap: 0.5rem;
  padding: 1.2rem 0;
  color: var(--muted-slate);
  font-size: 0.82rem;
}

.breadcrumbs a {
  color: var(--muted-slate);
  text-decoration: none;
}

.breadcrumbs a:hover {
  color: var(--neon-lime);
}

.breadcrumbs__sep {
  color: var(--safety-orange);
  font-family: var(--font-mono);
}

/* ---------- 11. 章节标题 ---------- */
.section-title {
  font-family: var(--font-serif);
  font-weight: 700;
  font-size: clamp(1.8rem, 4vw, 3rem);
  line-height: 1.25;
  letter-spacing: 0.02em;
  color: var(--ice-blue);
  margin-bottom: 0.75rem;
}

.section-title::after {
  content: "";
  display: block;
  width: 3.2rem;
  height: 3px;
  margin-top: 0.75rem;
  border-radius: 2px;
  background: var(--gradient-b);
  transform: skewX(-24deg);
}

.section-sub {
  font-size: 1.02rem;
  color: var(--muted-slate);
  max-width: 46rem;
}

/* ---------- 12. 基础组件 ---------- */
.glass-card {
  position: relative;
  background: var(--glass-white);
  border: 1px solid rgba(224, 242, 254, 0.08);
  border-radius: var(--radius-lg);
  -webkit-backdrop-filter: blur(12px);
  backdrop-filter: blur(12px);
  padding: 1.6rem;
  box-shadow: 0 10px 30px rgba(0, 0, 0, 0.12);
}

.tag {
  display: inline-flex;
  align-items: center;
  gap: 0.3rem;
  font-family: var(--font-mono);
  font-size: 0.74rem;
  color: var(--muted-slate);
  background: rgba(140, 160, 179, 0.08);
  border: 1px solid rgba(140, 160, 179, 0.2);
  border-radius: 999px;
  padding: 0.25rem 0.7rem;
  line-height: 1.4;
}

.tag--hot {
  color: var(--safety-orange);
  border-color: rgba(255, 107, 53, 0.4);
  background: rgba(255, 107, 53, 0.08);
}

.tag--live {
  color: var(--neon-lime);
  border-color: rgba(213, 255, 0, 0.35);
  background: rgba(213, 255, 0, 0.06);
}

.stat-num {
  font-family: var(--font-mono);
  font-weight: 500;
  font-variant-numeric: tabular-nums;
  font-size: 2rem;
  line-height: 1.1;
  color: var(--neon-lime);
}

.img-placeholder {
  position: relative;
  display: flex;
  align-items: center;
  justify-content: center;
  min-height: 10rem;
  border-radius: var(--radius-md);
  overflow: hidden;
  background:
    linear-gradient(135deg, rgba(213, 255, 0, 0.05), transparent 40%),
    linear-gradient(135deg, var(--ink-800), var(--ink-600));
  border: 1px solid rgba(224, 242, 254, 0.09);
}

.img-placeholder::before {
  content: "IMAGE";
  font-family: var(--font-mono);
  font-size: 0.7rem;
  letter-spacing: 0.28em;
  color: var(--muted-slate);
  opacity: 0.55;
}

.img-placeholder[data-label]::after {
  content: attr(data-label);
  position: absolute;
  left: 0.6rem;
  bottom: 0.6rem;
  font-family: var(--font-mono);
  font-size: 0.68rem;
  letter-spacing: 0.08em;
  color: var(--neon-lime);
  background: rgba(11, 22, 34, 0.78);
  padding: 0.2rem 0.5rem;
  border-radius: 4px;
}

/* ---------- 13. 滚动进度 / 返回顶部 ---------- */
.scroll-progress {
  position: fixed;
  top: 0;
  left: 0;
  height: 3px;
  width: 0;
  z-index: 9999;
  background: linear-gradient(90deg, var(--safety-orange) 0%, var(--neon-lime) 100%);
  pointer-events: none;
  will-change: width;
}

.back-top {
  position: fixed;
  right: 1.25rem;
  bottom: 1.25rem;
  z-index: 1000;
  display: flex;
  align-items: center;
  justify-content: center;
  width: 46px;
  height: 46px;
  border-radius: 50%;
  background: rgba(19, 35, 51, 0.85);
  -webkit-backdrop-filter: blur(10px);
  backdrop-filter: blur(10px);
  border: 1px solid rgba(213, 255, 0, 0.3);
  color: var(--neon-lime);
  font-family: var(--font-mono);
  font-size: 1.1rem;
  line-height: 1;
  box-shadow: 0 10px 24px rgba(0, 0, 0, 0.4);
  opacity: 0;
  transform: translateY(14px);
  pointer-events: none;
  transition: opacity 0.3s var(--ease), transform 0.3s var(--ease), background 0.2s, border-color 0.2s;
}

.back-top:hover {
  background: rgba(30, 52, 72, 0.95);
  border-color: var(--neon-lime);
}

.back-top.is-visible {
  opacity: 1;
  transform: translateY(0);
  pointer-events: auto;
}

/* ---------- 14. 响应式 ---------- */
@media (max-width: 880px) {
  .nav-toggle {
    display: inline-flex;
  }

  .header-navbar {
    justify-content: flex-end;
    padding: 0.4rem 1rem;
  }

  .header-nav {
    position: absolute;
    top: calc(100% - 0.4rem);
    left: 0.75rem;
    right: 0.75rem;
    z-index: 60;
    display: none;
    background: rgba(19, 35, 51, 0.98);
    -webkit-backdrop-filter: blur(18px);
    backdrop-filter: blur(18px);
    border: 1px solid rgba(224, 242, 254, 0.1);
    border-radius: 0 0 16px 16px;
    box-shadow: 0 20px 40px rgba(0, 0, 0, 0.5);
    padding: 0.5rem;
  }

  .header-nav[data-open] {
    display: block;
    animation: nav-drop 0.25s var(--ease);
  }

  .nav-list {
    flex-direction: column;
    align-items: stretch;
    gap: 0.15rem;
    padding: 0.25rem;
  }

  .nav-link {
    padding: 0.95rem 1rem;
    font-size: 1rem;
    border-radius: 10px;
    box-shadow: none;
  }

  .nav-link[aria-current="page"] {
    background: rgba(213, 255, 0, 0.08);
    box-shadow: inset 4px 0 0 var(--neon-lime);
  }

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

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

@keyframes nav-drop {
  from {
    opacity: 0;
    transform: translateY(-8px);
  }
  to {
    opacity: 1;
    transform: translateY(0);
  }
}

@media (max-width: 600px) {
  .header-main {
    padding: 1.6rem 1rem 1.2rem;
  }

  .header-dataline {
    padding-inline: 1rem;
    font-size: 0.66rem;
  }

  .footer-grid {
    grid-template-columns: 1fr;
    gap: 1.75rem;
  }

  .footer-bottom__meta {
    flex-direction: column;
    gap: 0.35rem;
  }
}

/* ---------- 15. 动画偏好 ---------- */
@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;
  }

  .live-dot {
    animation: none;
  }

  .header-nav[data-open],
  .back-top {
    animation: none;
    transition: none;
  }
}