/* =========================================================
   OBO体育 · 共享样式表 /assets/site.css
   纸白底 · 侧轨导览 · 直角细线 · 等宽索引
   ========================================================= */

/* ---------- 1. 设计变量 ---------- */
:root{
  --paper:#F6F3EA;
  --ink:#231D19;
  --sky:#1F6E9C;
  --cloud:#BBD3DF;
  --saffron:#B23A2E;
  --saffron-deep:#8E2C22;
  --gold:#C6A02C;
  --stone:#6E6459;
  --night:#0D2231;
  --ice:#E3EDF0;
  --meadow:#2E7D5B;

  --line:rgba(35,29,25,.14);
  --line-strong:rgba(35,29,25,.70);
  --line-invert:rgba(246,243,234,.20);

  --rail-w:96px;
  --topbar-h:64px;
  --gutter:clamp(20px,4vw,64px);
  --shell:1320px;

  --sans:"Source Han Sans SC","Noto Sans SC","PingFang SC","Hiragino Sans GB","Microsoft YaHei","Heiti SC",sans-serif;
  --mono:ui-monospace,"SFMono-Regular","JetBrains Mono","IBM Plex Mono",Menlo,Consolas,"Courier New",monospace;

  --ease:cubic-bezier(.22,.61,.36,1);
}

/* ---------- 2. 重置 ---------- */
*,*::before,*::after{box-sizing:border-box}
html{
  -webkit-text-size-adjust:100%;
  background-color:var(--paper);
  background-image:repeating-linear-gradient(
    0deg,
    rgba(35,29,25,.016) 0,
    rgba(35,29,25,.016) 1px,
    transparent 1px,
    transparent 3px
  );
}
body,h1,h2,h3,h4,h5,p,ul,ol,li,figure,blockquote,dl,dd{margin:0}
ul,ol{padding:0;list-style:none}
a{color:inherit;text-decoration:none}
button{font:inherit;color:inherit;background:none;border:0}
img,svg,picture{display:block;max-width:100%}
table{border-collapse:collapse;width:100%}
[hidden]{display:none !important}

/* ---------- 3. 中文排版基线 ---------- */
body{
  font-family:var(--sans);
  font-size:17px;
  line-height:1.85;
  font-weight:400;
  color:var(--ink);
  background:transparent;
  -webkit-font-smoothing:antialiased;
  -moz-osx-font-smoothing:grayscale;
}
p{max-width:38em}
h1,h2,h3,h4{text-wrap:balance}

.display{
  font-size:clamp(44px,7vw,108px);
  font-weight:900;
  line-height:.95;
  letter-spacing:-.03em;
}
.headline{
  font-size:clamp(28px,3.4vw,40px);
  font-weight:700;
  line-height:1.25;
  letter-spacing:-.01em;
}
.subhead{
  font-size:clamp(20px,2.2vw,24px);
  font-weight:700;
  line-height:1.45;
}
.mono{
  font-family:var(--mono);
  font-size:12px;
  font-weight:500;
  letter-spacing:.12em;
  text-transform:uppercase;
  color:var(--stone);
  line-height:1.6;
}
.label{
  font-size:13px;
  font-weight:600;
  letter-spacing:.05em;
  line-height:1.5;
}
.num-mark{
  display:inline-block;
  font-family:var(--mono);
  font-size:12px;
  font-weight:500;
  letter-spacing:.12em;
  color:var(--stone);
  padding-bottom:2px;
  border-bottom:1px solid var(--gold);
}

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

/* ---------- 4. 焦点与可访问性 ---------- */
:focus-visible{
  outline:2px solid var(--saffron);
  outline-offset:3px;
}
#main-content{display:block}
#main-content:focus{outline:none}
[id]{scroll-margin-top:88px}

.skip-link{
  position:fixed;
  top:0;
  left:0;
  z-index:300;
  transform:translateY(-130%);
  display:inline-block;
  padding:12px 20px;
  background:var(--ink);
  color:var(--paper);
  font-size:13px;
  font-weight:600;
  letter-spacing:.05em;
  transition:transform 180ms var(--ease);
}
.skip-link:focus,
.skip-link:focus-visible{
  transform:translateY(0);
  outline:2px solid var(--gold);
  outline-offset:0;
}

@media (prefers-reduced-motion:no-preference){
  html{scroll-behavior:smooth}
}

/* ---------- 5. 布局基元 ---------- */
.wrap{
  width:100%;
  max-width:var(--shell);
  margin-inline:auto;
  padding-inline:var(--gutter);
}
.prose{max-width:38em}
.prose > * + *{margin-top:1.1em}
.prose h2{
  font-size:clamp(24px,2.4vw,40px);
  font-weight:700;
  line-height:1.25;
  letter-spacing:-.01em;
  margin-top:1.6em;
}
.prose h3{
  font-size:24px;
  font-weight:700;
  line-height:1.4;
  margin-top:1.4em;
}
.prose a{
  color:var(--sky);
  border-bottom:1px solid var(--cloud);
}
.prose a:hover{color:var(--saffron);border-bottom-color:var(--saffron)}

.rule{
  border:0;
  height:1px;
  background:var(--line);
  margin-block:0;
}
.rule--ink{background:var(--line-strong)}

.grid{
  display:grid;
  grid-template-columns:repeat(12,minmax(0,1fr));
  gap:24px;
}
.s-3{grid-column:span 3}
.s-4{grid-column:span 4}
.s-5{grid-column:span 5}
.s-6{grid-column:span 6}
.s-7{grid-column:span 7}
.s-8{grid-column:span 8}
.s-9{grid-column:span 9}
.s-12{grid-column:span 12}
.start-2{grid-column-start:2}
.start-3{grid-column-start:3}

.band{padding-block:clamp(48px,7vw,96px)}
.band--paper{background:var(--paper)}
.band--cloud{background:var(--cloud)}
.band--ice{background:var(--ice)}
.band--night{background:var(--night);color:var(--paper)}
.band--night .mono{color:rgba(246,243,234,.72)}
.band--night .num-mark{
  color:rgba(246,243,234,.72);
  border-bottom-color:var(--gold);
}

/* ---------- 6. 按钮 ---------- */
.btn{
  display:inline-flex;
  align-items:center;
  justify-content:center;
  gap:10px;
  min-height:44px;
  padding:0 22px;
  border:1px solid var(--ink);
  border-radius:0;
  background:transparent;
  color:var(--ink);
  font-size:13px;
  font-weight:600;
  letter-spacing:.05em;
  line-height:1.2;
  text-align:center;
  cursor:pointer;
  transition:background-color 180ms var(--ease),color 180ms var(--ease),border-color 180ms var(--ease);
}
.btn--saffron{
  background:var(--saffron);
  border-color:var(--saffron);
  color:#fff;
}
.btn--saffron:hover{background:var(--saffron-deep);border-color:var(--saffron-deep)}
.btn--sky{
  background:var(--sky);
  border-color:var(--sky);
  color:#fff;
}
.btn--sky:hover{background:#175878;border-color:#175878}
.btn--ink{
  background:var(--ink);
  border-color:var(--ink);
  color:var(--paper);
}
.btn--ink:hover{background:var(--night);border-color:var(--night)}
.btn--ghost:hover{
  background:var(--ink);
  border-color:var(--ink);
  color:var(--paper);
}

/* ---------- 7. 头部：移动顶栏 ---------- */
.topbar{display:none}

.nav-toggle{
  display:inline-flex;
  align-items:center;
  gap:10px;
  min-height:44px;
  padding:0 14px;
  border:1px solid var(--ink);
  border-radius:0;
  background:transparent;
  font-size:13px;
  font-weight:600;
  letter-spacing:.05em;
  cursor:pointer;
  transition:background-color 180ms var(--ease),color 180ms var(--ease);
}
.nav-toggle:hover{background:var(--ice)}
.nav-toggle__bars{
  display:flex;
  flex-direction:column;
  gap:4px;
  width:18px;
}
.nav-toggle__bars i{
  display:block;
  height:2px;
  width:100%;
  background:var(--ink);
  transition:transform 200ms var(--ease),opacity 160ms var(--ease);
}
.nav-toggle__text{font-size:13px;font-weight:600;letter-spacing:.05em}

.site-header[data-open] .nav-toggle__bars i:nth-child(1){transform:translateY(6px) rotate(45deg)}
.site-header[data-open] .nav-toggle__bars i:nth-child(2){opacity:0}
.site-header[data-open] .nav-toggle__bars i:nth-child(3){transform:translateY(-6px) rotate(-45deg)}

/* ---------- 8. 头部：侧边轨道 ---------- */
.rail{
  position:fixed;
  top:0;
  left:0;
  bottom:0;
  width:var(--rail-w);
  display:flex;
  flex-direction:column;
  background:var(--paper);
  border-right:1px solid var(--ink);
  overflow-y:auto;
  overscroll-behavior:contain;
  z-index:90;
}

.rail__brand{
  display:flex;
  flex-direction:column;
  align-items:center;
  justify-content:center;
  gap:4px;
  min-height:96px;
  padding:16px 8px;
  background:var(--night);
  color:var(--paper);
  border-bottom:1px solid var(--night);
  transition:background-color 180ms var(--ease);
}
.rail__brand:hover{background:#0a1b27}
.rail__brand-main{
  font-size:22px;
  font-weight:900;
  letter-spacing:-.02em;
  line-height:1;
}
.rail__brand-sub{
  font-family:var(--mono);
  font-size:9px;
  font-weight:500;
  letter-spacing:.08em;
  line-height:1.4;
  color:var(--gold);
  text-align:center;
}

.rail__nav{display:block}
.rail__list{display:flex;flex-direction:column}
.rail__link{
  position:relative;
  display:flex;
  flex-direction:column;
  justify-content:center;
  gap:3px;
  min-height:44px;
  padding:12px 8px 12px 14px;
  border-bottom:1px solid var(--line);
  transition:background-color 180ms var(--ease),color 180ms var(--ease);
}
.rail__link::before{
  content:"";
  position:absolute;
  left:0;
  top:0;
  bottom:0;
  width:3px;
  background:var(--saffron);
  transform:scaleY(0);
  transform-origin:bottom;
  transition:transform 220ms var(--ease);
}
.rail__link:hover{background:var(--ice)}
.rail__num{
  align-self:flex-start;
  font-family:var(--mono);
  font-size:10px;
  font-weight:500;
  letter-spacing:.12em;
  color:var(--stone);
  line-height:1.3;
  padding-bottom:1px;
  border-bottom:1px solid var(--gold);
  transition:color 180ms var(--ease);
}
.rail__label{
  font-size:13px;
  font-weight:600;
  letter-spacing:.02em;
  line-height:1.4;
}
.rail__link[aria-current="page"]{color:var(--saffron);background:rgba(178,58,46,.06)}
.rail__link[aria-current="page"]::before{transform:scaleY(1)}
.rail__link[aria-current="page"] .rail__num{color:var(--saffron)}

.rail__cta{
  margin-top:auto;
  display:flex;
  flex-direction:column;
  align-items:center;
  justify-content:center;
  gap:3px;
  min-height:64px;
  padding:10px 6px;
  background:var(--saffron);
  color:#fff;
  font-size:13px;
  font-weight:600;
  letter-spacing:.05em;
  line-height:1.3;
  text-align:center;
  transition:background-color 180ms var(--ease);
}
.rail__cta:hover{background:var(--saffron-deep)}
.rail__cta-note{
  font-family:var(--mono);
  font-size:9px;
  font-weight:500;
  letter-spacing:.12em;
  color:rgba(255,255,255,.82);
}

.rail__meta{
  display:flex;
  flex-direction:column;
  gap:4px;
  padding:10px 6px 12px;
  border-top:1px solid var(--line);
  text-align:center;
}
.rail__meta-line{
  display:block;
  font-family:var(--mono);
  font-size:9px;
  font-weight:500;
  letter-spacing:.06em;
  line-height:1.5;
  color:var(--stone);
}

.nav-scrim{
  position:fixed;
  inset:0;
  z-index:85;
  background:rgba(13,34,49,.55);
  opacity:0;
  pointer-events:none;
  transition:opacity 220ms var(--ease);
}

/* ---------- 9. 页脚 ---------- */
.site-footer{
  position:relative;
  padding:clamp(48px,6vw,80px) var(--gutter) 32px;
  background:var(--night);
  color:var(--paper);
  border-top:1px solid var(--gold);
}
.site-footer__inner{
  max-width:var(--shell);
  margin-inline:auto;
}
.site-footer__top{
  display:grid;
  grid-template-columns:1fr;
  gap:clamp(32px,4vw,64px);
  padding-bottom:40px;
  border-bottom:1px solid var(--line-invert);
}
.site-footer__brand{min-width:0}
.site-footer__logo{
  font-size:clamp(28px,3vw,36px);
  font-weight:900;
  line-height:1.05;
  letter-spacing:-.02em;
  max-width:none;
}
.site-footer__sub{
  margin-top:10px;
  font-family:var(--mono);
  font-size:11px;
  font-weight:500;
  letter-spacing:.12em;
  line-height:1.6;
  color:var(--gold);
  max-width:none;
}
.site-footer__grid{
  display:grid;
  grid-template-columns:repeat(2,minmax(0,1fr));
  gap:32px 0;
}
.footer-col{
  padding-inline:clamp(10px,1.4vw,24px);
  border-left:1px solid var(--line-invert);
  min-width:0;
}
.footer-col:first-child{border-left:0;padding-left:0}
.footer-col__title{
  font-family:var(--mono);
  font-size:12px;
  font-weight:500;
  letter-spacing:.12em;
  line-height:1.6;
  color:var(--gold);
  margin-bottom:14px;
}
.footer-col__list li + li{margin-top:8px}
.footer-col__list a{
  display:inline-block;
  font-size:15px;
  line-height:1.6;
  color:rgba(246,243,234,.82);
  border-bottom:1px solid transparent;
  transition:color 180ms var(--ease),border-color 180ms var(--ease);
  overflow-wrap:anywhere;
}
.footer-col__list a:hover{
  color:var(--paper);
  border-bottom-color:var(--gold);
}
.site-footer__legal{
  display:flex;
  flex-wrap:wrap;
  gap:10px 32px;
  margin-top:28px;
}
.site-footer__legal-item{
  font-family:var(--mono);
  font-size:11px;
  font-weight:500;
  letter-spacing:.06em;
  line-height:1.8;
  color:rgba(246,243,234,.62);
  max-width:none;
}
.site-footer__legal-item--wide{flex-basis:100%}

/* ---------- 10. 通用内容组件 ---------- */
.media{
  position:relative;
  display:block;
  width:100%;
  aspect-ratio:16/9;
  overflow:hidden;
  background:var(--cloud);
  border:1px solid var(--line);
}
.media--wide{aspect-ratio:21/9}
.media--tall{aspect-ratio:3/4}
.media--square{aspect-ratio:1/1}
.media img{
  width:100%;
  height:100%;
  object-fit:cover;
  display:block;
}
.media__scrim{
  position:absolute;
  inset:auto 0 0 0;
  height:55%;
  background:rgba(13,34,49,.55);
  pointer-events:none;
}
.media__meta{
  position:absolute;
  left:0;
  bottom:0;
  right:0;
  padding:16px;
  color:var(--paper);
  font-family:var(--mono);
  font-size:11px;
  font-weight:500;
  letter-spacing:.12em;
  line-height:1.6;
}

.tags{display:flex;flex-wrap:wrap;gap:8px}
.tag{
  display:inline-flex;
  align-items:center;
  min-height:38px;
  padding:0 14px;
  border:1px solid var(--line);
  border-radius:0;
  background:transparent;
  color:var(--stone);
  font-family:var(--mono);
  font-size:12px;
  font-weight:500;
  letter-spacing:.1em;
  line-height:1;
  cursor:pointer;
  transition:background-color 180ms var(--ease),color 180ms var(--ease),border-color 180ms var(--ease);
}
.tag:hover{border-color:var(--ink);color:var(--ink)}
.tag[aria-pressed="true"]{
  background:var(--ink);
  border-color:var(--ink);
  color:var(--paper);
}

.index-table{font-size:17px;line-height:1.6}
.index-table caption{
  text-align:left;
  font-family:var(--mono);
  font-size:12px;
  letter-spacing:.12em;
  color:var(--stone);
  padding-bottom:12px;
}
.index-table th,
.index-table td{
  padding:14px 12px;
  border-bottom:1px solid var(--line);
  text-align:left;
  vertical-align:top;
}
.index-table thead th{
  font-family:var(--mono);
  font-size:12px;
  font-weight:500;
  letter-spacing:.12em;
  color:var(--stone);
  border-bottom:1px solid var(--line-strong);
  white-space:nowrap;
}
.index-table tbody tr:nth-child(even){background:var(--ice)}
.index-table td:first-child{
  font-family:var(--mono);
  font-size:12px;
  letter-spacing:.12em;
  color:var(--stone);
  white-space:nowrap;
}

.breadcrumb{
  display:flex;
  flex-wrap:wrap;
  align-items:center;
  gap:8px;
  font-family:var(--mono);
  font-size:12px;
  font-weight:500;
  letter-spacing:.08em;
  color:var(--stone);
  line-height:1.8;
}
.breadcrumb li{display:inline-flex;align-items:center;gap:8px}
.breadcrumb li + li::before{
  content:"/";
  color:var(--gold);
}
.breadcrumb a{color:var(--stone);border-bottom:1px solid transparent}
.breadcrumb a:hover{color:var(--saffron);border-bottom-color:var(--saffron)}
.breadcrumb [aria-current="page"]{color:var(--ink)}

/* 折叠组 */
.acc{border-top:1px solid var(--ink)}
.acc__item{border-bottom:1px solid var(--line)}
.acc__trigger{
  display:flex;
  align-items:flex-start;
  justify-content:space-between;
  gap:16px;
  width:100%;
  min-height:64px;
  padding:20px 0;
  text-align:left;
  font-size:17px;
  font-weight:600;
  line-height:1.5;
  cursor:pointer;
  transition:color 180ms var(--ease);
}
.acc__trigger:hover{color:var(--saffron)}
.acc__sign{
  position:relative;
  flex:none;
  width:16px;
  height:16px;
  margin-top:5px;
}
.acc__sign::before,
.acc__sign::after{
  content:"";
  position:absolute;
  background:currentColor;
  transition:transform 220ms var(--ease),opacity 160ms var(--ease);
}
.acc__sign::before{left:0;top:7px;width:16px;height:2px}
.acc__sign::after{left:7px;top:0;width:2px;height:16px}
.acc__item[data-open] .acc__sign::after{transform:scaleY(0);opacity:0}
.acc__item[data-open] .acc__trigger{color:var(--saffron)}
.acc__panel{
  display:grid;
  grid-template-rows:0fr;
  transition:grid-template-rows 260ms var(--ease);
}
.acc__item[data-open] .acc__panel{grid-template-rows:1fr}
.acc__panel-inner{overflow:hidden}
.acc__panel-body{
  max-width:38em;
  padding:0 0 24px;
  color:var(--stone);
  opacity:0;
  transition:opacity 160ms var(--ease) 120ms;
}
.acc__item[data-open] .acc__panel-body{opacity:1}

/* 入场显现 */
html.js [data-reveal]{
  opacity:0;
  transform:translateY(12px);
  transition:opacity 420ms var(--ease),transform 420ms var(--ease);
}
html.js [data-reveal].is-visible{
  opacity:1;
  transform:none;
}

/* ---------- 11. 桌面端主体偏移 ---------- */
@media (min-width:1080px){
  body{padding-left:var(--rail-w);padding-top:0}
  .site-footer__top{grid-template-columns:260px minmax(0,1fr)}
  .site-footer__grid{grid-template-columns:repeat(4,minmax(0,1fr))}
  .site-footer__legal-item--wide{flex-basis:auto}
  [id]{scroll-margin-top:32px}
}

/* ---------- 12. 移动端与平板：顶栏 + 抽屉 ---------- */
@media (max-width:1079px){
  body{padding-top:var(--topbar-h);padding-left:0}
  body.is-nav-open{overflow:hidden}

  .topbar{
    position:fixed;
    top:0;
    left:0;
    right:0;
    z-index:80;
    display:flex;
    align-items:center;
    justify-content:space-between;
    gap:16px;
    height:var(--topbar-h);
    padding:0 16px;
    background:var(--paper);
    border-bottom:1px solid var(--ink);
  }
  .topbar__brand{
    display:flex;
    align-items:baseline;
    gap:8px;
    min-height:44px;
    padding-block:8px;
  }
  .topbar__mark{
    font-size:20px;
    font-weight:900;
    letter-spacing:-.02em;
    line-height:1;
  }
  .topbar__sub{
    font-family:var(--mono);
    font-size:10px;
    font-weight:500;
    letter-spacing:.1em;
    color:var(--stone);
  }

  .rail{
    width:min(86vw,360px);
    border-right:1px solid var(--ink);
    transform:translateX(-101%);
    transition:transform 260ms var(--ease);
    z-index:90;
  }
  .site-header[data-open] .rail{transform:translateX(0)}
  .site-header[data-open] .nav-scrim{
    opacity:1;
    pointer-events:auto;
  }

  .rail__brand{min-height:104px;padding:22px 16px;align-items:flex-start}
  .rail__brand-main{font-size:28px}
  .rail__brand-sub{font-size:10px;text-align:left}
  .rail__link{padding:16px 16px 16px 20px;gap:4px}
  .rail__label{font-size:15px}
  .rail__num{font-size:11px}
  .rail__cta{min-height:72px;font-size:15px}
  .rail__cta-note{font-size:10px}
  .rail__meta{padding:14px 16px 20px;text-align:left}
  .rail__meta-line{font-size:10px}

  .grid{grid-template-columns:repeat(4,minmax(0,1fr));gap:16px}
  .s-3,.s-4,.s-5,.s-6,.s-7,.s-8,.s-9,.s-12{grid-column:span 4}
  .start-2,.start-3{grid-column-start:1}

  .site-footer__grid{grid-template-columns:repeat(2,minmax(0,1fr));gap:32px 24px}
  .footer-col{border-left:0;padding-inline:0}
}

@media (max-width:560px){
  .topbar__sub{display:none}
  .site-footer__grid{grid-template-columns:1fr;gap:28px}
  .index-table{font-size:15px}
  .index-table th,.index-table td{padding:12px 8px}
  .index-table td:first-child{white-space:normal}
  .acc__trigger{font-size:16px}
}

/* ---------- 13. 减弱动效 ---------- */
@media (prefers-reduced-motion:reduce){
  *,
  *::before,
  *::after{
    animation-duration:.001ms !important;
    animation-iteration-count:1 !important;
    transition-duration:.001ms !important;
    scroll-behavior:auto !important;
  }
  html.js [data-reveal]{
    opacity:1;
    transform:none;
  }
  .rail__link::before{transition:none}
}