/* ==========================================================================
   千亿球友会站 · /assets/site.css
   共享外壳：reset / 变量 / 中文排版 / 头部 / 页脚 / 通用组件
   ========================================================================== */

/* ---------- 变量 ---------- */
:root{
  --c-deep:#08192B;
  --c-mid:#0F2A44;
  --c-line:#1C3D5C;
  --c-mist:#E9EEF3;
  --c-cyan:#35D6E3;
  --c-cyan-soft:#8EE9F0;
  --c-gold:#E3B24F;
  --c-gold-soft:#F4DA9A;
  --c-flare:#FF5B3D;
  --c-paper:#F2F6FA;
  --c-ink:#0F2A44;
  --c-muted:#8FA9BD;
  --c-dim:#6B879E;

  --font-sans:"PingFang SC","Hiragino Sans GB","Source Han Sans SC","Noto Sans CJK SC","Microsoft YaHei",system-ui,-apple-system,"Segoe UI",Roboto,sans-serif;
  --font-mono:ui-monospace,SFMono-Regular,"JetBrains Mono","Roboto Mono",Menlo,Consolas,monospace;

  --wrap:1240px;
  --gutter:clamp(18px,4vw,44px);
  --cut:18px;
  --ease:cubic-bezier(.22,.61,.36,1);
}

/* ---------- reset ---------- */
*,*::before,*::after{box-sizing:border-box}
html{-webkit-text-size-adjust:100%;scroll-behavior:smooth}
body{
  margin:0;
  background:var(--c-deep);
  color:var(--c-paper);
  font-family:var(--font-sans);
  font-size:16px;
  line-height:1.75;
  overflow-x:hidden;
  -webkit-font-smoothing:antialiased;
  text-rendering:optimizeLegibility;
}
h1,h2,h3,h4,p,ul,ol,dl,dd,figure{margin:0}
ul,ol{padding:0;list-style:none}
img,svg,video{display:block;max-width:100%}
button,input,select,textarea{font:inherit;color:inherit}
a{color:inherit}
table{border-collapse:collapse}

/* ---------- 中文排版 ---------- */
h1,h2,h3,h4{font-weight:800;line-height:1.12;letter-spacing:-.02em;color:var(--c-paper)}
h1{font-size:clamp(34px,5vw,56px)}
h2{font-size:clamp(26px,3.2vw,40px)}
h3{font-size:clamp(20px,2.2vw,28px)}
h4{font-size:19px;letter-spacing:-.01em}
p{line-height:1.75}
strong{font-weight:700;color:var(--c-cyan-soft)}
.prose{max-width:38em}
.mono{font-family:var(--font-mono);font-variant-numeric:tabular-nums;letter-spacing:.01em}

/* ---------- 焦点与可访问 ---------- */
:focus-visible{outline:2px solid var(--c-cyan);outline-offset:3px}
.skip-link{
  position:fixed;top:10px;left:10px;z-index:300;
  transform:translateY(-220%);
  padding:10px 20px;
  background:var(--c-cyan);color:#04202A;
  font-size:14px;font-weight:700;letter-spacing:.02em;text-decoration:none;
  transition:transform .2s var(--ease);
}
.skip-link:focus,.skip-link:focus-visible{transform:translateY(0)}

/* ---------- 容器 ---------- */
.wrap{width:100%;max-width:var(--wrap);margin:0 auto;padding-left:var(--gutter);padding-right:var(--gutter)}

/* ==========================================================================
   头部
   ========================================================================== */
.site-header{
  position:sticky;top:0;z-index:120;
  background:var(--c-deep);
  border-bottom:1px solid var(--c-line);
  color:var(--c-paper);
  transition:box-shadow .24s var(--ease);
}
.site-header[data-condensed="true"]{box-shadow:0 12px 34px rgba(0,0,0,.5)}
.site-header[data-condensed="true"] .site-header__brandrow{padding-top:9px;padding-bottom:9px}

/* 状态栏 */
.status-bar{background:#040D18;border-bottom:1px solid #12304A}
.status-bar__inner{
  max-width:var(--wrap);margin:0 auto;
  display:flex;align-items:center;gap:clamp(14px,2.6vw,34px);
  padding:7px var(--gutter);
  font-size:12px;letter-spacing:.14em;line-height:1.6;
  overflow-x:auto;scrollbar-width:none;
}
.status-bar__inner::-webkit-scrollbar{display:none}
.status-bar__item{display:inline-flex;align-items:center;gap:8px;color:#93AEC4;white-space:nowrap}
.status-bar__dot{
  flex:none;width:7px;height:7px;border-radius:50%;
  background:var(--c-cyan);
  box-shadow:0 0 0 4px rgba(53,214,227,.14);
}
.status-bar__link{
  white-space:nowrap;color:#93AEC4;text-decoration:none;
  border-bottom:1px solid transparent;
  transition:color .18s var(--ease),border-color .18s var(--ease);
}
.status-bar__link:hover{color:var(--c-cyan);border-bottom-color:var(--c-cyan)}
.status-bar__link--channel{color:var(--c-gold-soft)}
.status-bar__link--channel:hover{color:var(--c-gold);border-bottom-color:var(--c-gold)}

/* 品牌说明层 */
.site-header__brandrow{
  max-width:var(--wrap);margin:0 auto;
  display:flex;align-items:center;justify-content:space-between;gap:28px;
  padding:16px var(--gutter);
  transition:padding .24s var(--ease);
}
.brand{display:inline-flex;align-items:center;gap:14px;text-decoration:none;color:inherit;min-width:0}
.brand__mark{
  flex:none;display:grid;place-items:center;
  width:46px;height:46px;
  background:var(--c-cyan);color:#04202A;
  font-family:var(--font-mono);font-size:15px;font-weight:700;letter-spacing:.04em;
  clip-path:polygon(12px 0,100% 0,100% calc(100% - 12px),calc(100% - 12px) 100%,0 100%,0 12px);
}
.brand__text{display:flex;flex-direction:column;gap:3px;min-width:0}
.brand__name{font-size:18px;font-weight:800;letter-spacing:.02em;line-height:1.2;white-space:nowrap}
.brand__tag{font-size:11px;letter-spacing:.14em;color:var(--c-dim);line-height:1.4}

.header-note{display:flex;flex-direction:column;align-items:flex-end;gap:6px;text-align:right}
.header-note__line{font-size:13px;line-height:1.6;color:#A8BFD2;max-width:46ch}
.header-note__meta{
  font-family:var(--font-mono);font-variant-numeric:tabular-nums;
  font-size:11px;letter-spacing:.12em;color:var(--c-gold);
}

/* 主导航层 */
.main-nav{position:relative;background:#0A1F33;border-top:1px solid var(--c-line)}
.main-nav__inner{
  max-width:var(--wrap);margin:0 auto;
  padding:0 var(--gutter);
  display:flex;align-items:center;justify-content:space-between;gap:20px;
  min-height:54px;
}
.nav-list{display:flex;align-items:center;gap:2px}
.nav-list__item{display:block}
.nav-link{
  position:relative;display:block;
  padding:16px 14px;
  font-size:15px;font-weight:600;line-height:1.2;
  color:#AFC5D6;text-decoration:none;
  transition:color .18s var(--ease);
}
.nav-link::after{
  content:"";position:absolute;left:14px;right:14px;bottom:9px;height:2px;
  background:var(--c-cyan);
  transform:scaleX(0);transform-origin:left center;
  transition:transform .24s var(--ease);
}
.nav-link:hover{color:var(--c-paper)}
.nav-link:hover::after{transform:scaleX(1)}
.nav-link[aria-current="page"]{color:var(--c-cyan)}
.nav-link[aria-current="page"]::after{transform:scaleX(1)}

/* 移动按钮 */
.nav-toggle{
  display:none;align-items:center;gap:10px;
  padding:9px 14px;
  background:transparent;color:var(--c-paper);
  border:1px solid var(--c-line);cursor:pointer;
  font-size:12px;letter-spacing:.16em;
  transition:border-color .18s var(--ease),color .18s var(--ease);
}
.nav-toggle:hover{border-color:var(--c-cyan);color:var(--c-cyan)}
.nav-toggle__bars{position:relative;flex:none;width:16px;height:10px}
.nav-toggle__bars::before,
.nav-toggle__bars::after{
  content:"";position:absolute;left:0;width:16px;height:2px;
  background:currentColor;
  transition:transform .24s var(--ease);
}
.nav-toggle__bars::before{top:0}
.nav-toggle__bars::after{bottom:0}
.nav-toggle[aria-expanded="true"] .nav-toggle__bars::before{transform:translateY(4px) rotate(45deg)}
.nav-toggle[aria-expanded="true"] .nav-toggle__bars::after{transform:translateY(-4px) rotate(-45deg)}
.nav-toggle__label{white-space:nowrap}

/* 移动吸底入口条 */
.mobile-cta{display:none}
.mobile-cta__label{font-size:12px;letter-spacing:.16em;color:var(--c-muted);white-space:nowrap}
.mobile-cta__links{display:flex;align-items:center;gap:8px}

/* ==========================================================================
   页脚
   ========================================================================== */
.site-footer{
  background:#040D18;
  border-top:1px solid var(--c-line);
  color:var(--c-paper);
}
.footer__grid{
  max-width:var(--wrap);margin:0 auto;
  padding:clamp(46px,7vw,84px) var(--gutter) clamp(30px,4vw,48px);
  display:grid;
  grid-template-columns:minmax(0,1.15fr) minmax(0,1fr) minmax(0,1.05fr);
  gap:clamp(28px,4vw,56px);
}
.footer__brand{display:flex;flex-direction:column;align-items:flex-start;gap:16px}
.footer__logo{
  display:inline-flex;align-items:center;gap:12px;
  font-size:18px;font-weight:800;letter-spacing:.03em;
  color:var(--c-paper);text-decoration:none;
}
.footer__mark{
  display:grid;place-items:center;flex:none;
  width:34px;height:34px;
  border:1px solid var(--c-cyan);color:var(--c-cyan);
  font-family:var(--font-mono);font-size:12px;font-weight:700;
  clip-path:polygon(9px 0,100% 0,100% calc(100% - 9px),calc(100% - 9px) 100%,0 100%,0 9px);
}
.footer__summary{font-size:14px;line-height:1.85;color:#9FB6C9;max-width:36ch}
.footer__meta{
  font-family:var(--font-mono);font-variant-numeric:tabular-nums;
  font-size:12px;letter-spacing:.1em;color:var(--c-gold);
}
.footer__cols{display:grid;grid-template-columns:repeat(2,minmax(0,1fr));gap:clamp(20px,3vw,40px)}
.footer-col{display:flex;flex-direction:column;gap:14px}
.footer-col__title{
  font-size:12px;font-weight:700;letter-spacing:.2em;
  color:var(--c-dim);line-height:1.5;
}
.footer-col__list{display:flex;flex-direction:column;gap:10px}
.footer-link{
  font-size:14px;color:#AFC5D6;text-decoration:none;
  transition:color .18s var(--ease),padding-left .18s var(--ease);
}
.footer-link:hover{color:var(--c-cyan);padding-left:4px}

.footer__contact{display:flex;flex-direction:column;gap:14px}
.contact-list{display:flex;flex-direction:column;gap:13px}
.contact-list__item{display:flex;flex-direction:column;gap:3px}
.contact-list__label{font-size:11px;letter-spacing:.18em;color:var(--c-dim);line-height:1.5}
.contact-list__value{
  display:flex;flex-wrap:wrap;align-items:center;gap:10px;
  font-family:var(--font-mono);font-variant-numeric:tabular-nums;
  font-size:14px;line-height:1.6;color:#D5E2EC;
}
.contact-list__value--plain{font-family:var(--font-sans);font-variant-numeric:normal;letter-spacing:.01em}
.copy-btn{
  display:inline-flex;align-items:center;gap:6px;
  padding:4px 9px;
  background:transparent;border:1px solid var(--c-line);color:var(--c-muted);
  cursor:pointer;font-size:11px;letter-spacing:.14em;line-height:1.4;
  transition:border-color .18s var(--ease),color .18s var(--ease);
}
.copy-btn:hover{border-color:var(--c-cyan);color:var(--c-cyan)}
.copy-btn[data-copy-state="done"]{border-color:var(--c-cyan);color:var(--c-cyan)}
.copy-btn[data-copy-state="fail"]{border-color:var(--c-flare);color:var(--c-flare)}
.copy-btn__label{white-space:nowrap}

.footer__bottom{
  max-width:var(--wrap);margin:0 auto;
  padding:18px var(--gutter) 30px;
  border-top:1px solid var(--c-line);
  display:flex;flex-wrap:wrap;align-items:center;justify-content:space-between;gap:12px 28px;
  font-size:12px;letter-spacing:.1em;color:var(--c-dim);
}
.footer__legal{display:inline-flex;flex-wrap:wrap;align-items:center;gap:8px 20px;line-height:1.7}

/* ==========================================================================
   通用组件
   ========================================================================== */
/* 章节 */
.section{max-width:var(--wrap);margin:0 auto;padding:clamp(40px,6vw,76px) var(--gutter)}
.section__head{display:flex;flex-direction:column;gap:12px;max-width:56ch;margin-bottom:clamp(24px,3.5vw,44px)}
.section__eyebrow{
  font-family:var(--font-mono);font-variant-numeric:tabular-nums;
  font-size:12px;letter-spacing:.2em;color:var(--c-cyan);line-height:1.5;
}
.section__title{font-size:clamp(24px,3vw,38px)}
.section__lead{font-size:16px;line-height:1.8;color:#A8BFD2;max-width:38em}

/* 左右分屏 */
.split{
  max-width:var(--wrap);margin:0 auto;
  padding:clamp(32px,5vw,64px) var(--gutter);
  display:grid;
  grid-template-columns:minmax(0,32fr) minmax(0,68fr);
  gap:clamp(24px,4vw,56px);
  align-items:start;
}
.split__aside{position:sticky;top:136px;min-width:0}
.split__main{min-width:0}

/* 左侧索引 */
.rail-index{border-left:1px solid var(--c-line)}
.rail-index__title{
  font-family:var(--font-mono);font-size:11px;letter-spacing:.2em;
  color:var(--c-dim);line-height:1.6;
  margin:0 0 14px;padding-left:16px;
}
.rail-index__list{display:flex;flex-direction:column}
.rail-index__item{display:block}
.rail-index__link{
  display:block;
  padding:9px 12px 9px 16px;margin-left:-1px;
  border-left:2px solid transparent;
  font-size:14px;line-height:1.55;color:#8FA9BD;text-decoration:none;
  transition:color .18s var(--ease),border-color .18s var(--ease),background .18s var(--ease);
}
.rail-index__link:hover{color:var(--c-paper);background:rgba(53,214,227,.06)}
.rail-index__link[aria-current]{
  color:var(--c-cyan);border-left-color:var(--c-cyan);
  background:rgba(53,214,227,.08);
}

/* 面板 */
.panel{
  position:relative;
  background:var(--c-mid);
  border:1px solid var(--c-line);
  padding:clamp(18px,2.4vw,28px);
}
.panel--cut{
  clip-path:polygon(0 0,calc(100% - var(--cut)) 0,100% var(--cut),100% 100%,var(--cut) 100%,0 calc(100% - var(--cut)));
}
.panel--mist{background:var(--c-mist);border-color:#C7D6E3;color:var(--c-ink)}
.panel--mist h2,.panel--mist h3,.panel--mist h4{color:var(--c-ink)}
.panel--mist p{color:#2A4A66}

/* 网格 */
.grid{display:grid;gap:clamp(16px,2.4vw,28px)}
.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))}

/* 标签 */
.tag{
  display:inline-flex;align-items:center;gap:6px;
  padding:4px 10px;
  border:1px solid rgba(53,214,227,.35);background:rgba(53,214,227,.1);
  color:var(--c-cyan-soft);
  font-size:12px;letter-spacing:.1em;line-height:1.5;
}
.tag--cyan{background:var(--c-cyan);border-color:var(--c-cyan);color:#04202A;font-weight:700}
.tag--gold{border-color:rgba(227,178,79,.42);background:rgba(227,178,79,.14);color:var(--c-gold-soft)}

/* 旁注 */
.note-rail{
  writing-mode:vertical-rl;
  font-size:12px;letter-spacing:.16em;line-height:1;
  color:var(--c-dim);
}
.note-rail--rotate{
  writing-mode:horizontal-tb;
  transform:rotate(-90deg);transform-origin:left top;
  white-space:nowrap;
}

/* 图片容器 */
.figure{display:block;margin:0}
.figure__frame{
  position:relative;overflow:hidden;
  border:1px solid var(--c-line);
  background:linear-gradient(135deg,#0F2A44 0%,#123C5B 52%,#08192B 100%);
  clip-path:polygon(0 0,calc(100% - 22px) 0,100% 22px,100% 100%,22px 100%,0 calc(100% - 22px));
}
.figure__frame::after{
  content:"";position:absolute;inset:0;pointer-events:none;opacity:.4;
  background-image:repeating-linear-gradient(115deg,rgba(53,214,227,.12) 0 1px,transparent 1px 22px);
}
.figure__img{
  display:block;width:100%;
  aspect-ratio:16 / 9;object-fit:cover;
  background:linear-gradient(135deg,#0F2A44 0%,#123C5B 52%,#08192B 100%);
}
.figure--wide .figure__img{aspect-ratio:21 / 9}
.figure--tall .figure__img{aspect-ratio:4 / 5}
.figure--square .figure__img{aspect-ratio:1 / 1}
.figure__caption{
  display:block;margin-top:10px;
  font-size:12px;letter-spacing:.14em;line-height:1.7;color:var(--c-dim);
}

/* 面包屑 */
.breadcrumb{
  display:flex;flex-wrap:wrap;align-items:center;gap:8px;
  font-size:12px;letter-spacing:.14em;line-height:1.6;color:var(--c-dim);
}
.breadcrumb__item{display:inline-flex;align-items:center;gap:8px}
.breadcrumb__item a{color:#9FB6C9;text-decoration:none;transition:color .18s var(--ease)}
.breadcrumb__item a:hover{color:var(--c-cyan)}
.breadcrumb__item[aria-current="page"]{color:var(--c-cyan-soft)}
.breadcrumb__sep{color:var(--c-line)}

/* 按钮 */
.btn{
  display:inline-flex;align-items:center;justify-content:center;gap:10px;
  padding:12px 22px;
  border:1px solid transparent;
  font-size:15px;font-weight:600;line-height:1.2;letter-spacing:.02em;
  text-decoration:none;cursor:pointer;
  transition:transform .18s var(--ease),background .18s var(--ease),border-color .18s var(--ease),color .18s var(--ease);
}
.btn--primary{background:var(--c-cyan);border-color:var(--c-cyan);color:#04202A}
.btn--primary:hover{background:var(--c-cyan-soft);border-color:var(--c-cyan-soft);transform:translateY(-2px)}
.btn--gold{background:var(--c-gold);border-color:var(--c-gold);color:#241A06}
.btn--gold:hover{background:var(--c-gold-soft);border-color:var(--c-gold-soft);transform:translateY(-2px)}
.btn--ghost{background:transparent;border-color:var(--c-line);color:var(--c-paper)}
.btn--ghost:hover{border-color:var(--c-cyan);color:var(--c-cyan);transform:translateY(-2px)}
.btn--sm{padding:8px 14px;font-size:13px}

/* ---------- 滚动显现 ---------- */
.js [data-reveal]{
  opacity:0;transform:translateY(16px);
  transition:opacity .55s var(--ease),transform .55s var(--ease);
  transition-delay:var(--reveal-delay,0ms);
}
.js [data-reveal].is-in{opacity:1;transform:none}

/* ==========================================================================
   响应式
   ========================================================================== */
@media (max-width:1080px){
  .footer__grid{grid-template-columns:minmax(0,1fr) minmax(0,1fr)}
  .footer__brand{grid-column:1 / -1}
  .header-note__line{max-width:34ch}
}

@media (max-width:960px){
  .site-header__brandrow{padding-top:12px;padding-bottom:12px}
  .header-note{display:none}
  .nav-toggle{display:inline-flex}
  .main-nav__inner{justify-content:flex-end;min-height:50px}
  .nav-list{
    position:absolute;left:0;right:0;top:100%;
    flex-direction:column;align-items:stretch;gap:0;
    background:#0A1F33;border-top:1px solid var(--c-line);
    padding:6px var(--gutter) 18px;
    max-height:0;overflow:hidden;visibility:hidden;opacity:0;
    transition:max-height .3s var(--ease),opacity .24s var(--ease),visibility .3s;
  }
  .main-nav[data-open] .nav-list{max-height:480px;visibility:visible;opacity:1}
  .nav-link{padding:14px 0;border-bottom:1px solid rgba(28,61,92,.7)}
  .nav-link::after{left:0;right:auto;width:38px;bottom:7px}

  .mobile-cta{
    display:flex;align-items:center;justify-content:space-between;gap:14px;
    position:fixed;left:0;right:0;bottom:0;z-index:110;
    padding:10px var(--gutter) calc(10px + env(safe-area-inset-bottom,0px));
    background:rgba(4,13,24,.96);
    border-top:1px solid var(--c-line);
  }
  body{padding-bottom:78px}

  .split{grid-template-columns:minmax(0,1fr)}
  .split__aside{position:static;top:auto}
  .grid--3,.grid--4{grid-template-columns:repeat(2,minmax(0,1fr))}
}

@media (max-width:680px){
  .footer__grid{grid-template-columns:minmax(0,1fr)}
  .footer__cols{grid-template-columns:repeat(2,minmax(0,1fr))}
  .footer__bottom{flex-direction:column;align-items:flex-start}
  .grid--2,.grid--3,.grid--4{grid-template-columns:minmax(0,1fr)}
  .brand__mark{width:40px;height:40px;font-size:13px}
  .brand__name{font-size:16px}
  .status-bar__inner{font-size:11px}
}

@media (max-width:420px){
  .footer__cols{grid-template-columns:minmax(0,1fr)}
  .mobile-cta__label{display:none}
}

/* ==========================================================================
   动效降级
   ========================================================================== */
@media (prefers-reduced-motion:reduce){
  html{scroll-behavior:auto}
  *,*::before,*::after{
    animation-duration:.01ms !important;
    animation-iteration-count:1 !important;
    transition-duration:.01ms !important;
  }
  .js [data-reveal]{opacity:1;transform:none}
}