/* ============================================================
   博万体育看台 · 共享外壳样式 /assets/site.css
   看台炭黑底色 + 蓝图坐标细线 + −12° 斜切签名
   ============================================================ */

/* ---------- 1. 变量 ---------- */
:root{
  --bw-charcoal:#14161A;
  --bw-asphalt:#23262B;
  --bw-concrete:#E8E5DE;
  --bw-red:#C8332B;
  --bw-red-dark:#8E1F1A;
  --bw-green:#2F7A4F;
  --bw-green-ink:#8FD0AB;
  --bw-amber:#F2B233;
  --bw-white:#F7F6F3;
  --bw-blue:#4A7FA5;
  --bw-ink:#1B1D21;

  --bw-line:rgba(74,127,165,.28);
  --bw-line-strong:rgba(74,127,165,.58);
  --bw-line-soft:rgba(232,229,222,.10);
  --bw-tick:rgba(74,127,165,.42);

  --bw-text:var(--bw-white);
  --bw-text-dim:rgba(247,246,243,.68);
  --bw-text-faint:rgba(247,246,243,.46);

  --bw-serif:"Noto Serif SC","Source Han Serif SC","Songti SC","SimSun",Georgia,serif;
  --bw-sans:"Noto Sans SC","Source Han Sans SC","PingFang SC","Hiragino Sans GB","Microsoft YaHei",Inter,system-ui,-apple-system,sans-serif;
  --bw-mono:"IBM Plex Mono","Roboto Mono",ui-monospace,SFMono-Regular,Menlo,Consolas,monospace;

  --bw-wrap:1240px;
  --bw-gutter:clamp(16px,3.6vw,40px);
  --bw-rail:104px;
  --bw-cut:10px;
  --bw-cut-path:polygon(0 0,calc(100% - var(--bw-cut)) 0,100% var(--bw-cut),100% 100%,var(--bw-cut) 100%,0 calc(100% - var(--bw-cut)));
  --bw-slant:-12deg;
  --bw-ease:cubic-bezier(.2,.7,.3,1);
}

/* ---------- 2. reset ---------- */
*,*::before,*::after{box-sizing:border-box}
html{-webkit-text-size-adjust:100%;scroll-behavior:smooth}
body,h1,h2,h3,h4,h5,p,ul,ol,li,figure,figcaption,blockquote,dl,dt,dd,table,fieldset{margin:0;padding:0}
ul,ol{list-style:none}
table{border-collapse:collapse}
button{font:inherit;color:inherit;background:none;border:0;cursor:pointer}
a{color:inherit;text-decoration:none}
img,svg,video{display:block;max-width:100%}
:focus-visible{outline:2px solid var(--bw-amber);outline-offset:3px;border-radius:2px}
::selection{background:var(--bw-red);color:var(--bw-white)}

/* ---------- 3. 中文排版与页面底纹 ---------- */
body{
  font-family:var(--bw-sans);
  font-size:16px;
  font-weight:400;
  line-height:1.75;
  letter-spacing:.006em;
  color:var(--bw-text);
  min-height:100vh;
  background-color:var(--bw-charcoal);
  background-image:
    repeating-linear-gradient(90deg,rgba(74,127,165,.055) 0 1px,transparent 1px 120px),
    repeating-linear-gradient(0deg,rgba(74,127,165,.040) 0 1px,transparent 1px 120px),
    radial-gradient(900px 520px at 10% -12%,rgba(200,51,43,.12),transparent 70%),
    radial-gradient(760px 460px at 92% 2%,rgba(47,122,79,.09),transparent 72%);
  background-attachment:fixed;
}
body::after{
  content:"";
  position:fixed;
  inset:0;
  z-index:120;
  pointer-events:none;
  opacity:.75;
  background-image:
    radial-gradient(rgba(247,246,243,.045) 1px,transparent 1.1px),
    radial-gradient(rgba(242,178,51,.030) 1px,transparent 1.1px);
  background-size:3px 3px,7px 7px;
  background-position:0 0,2px 3px;
}

/* ---------- 4. 骨架容器 ---------- */
.bw-wrap{width:100%;max-width:var(--bw-wrap);margin-inline:auto;padding-inline:var(--bw-gutter)}
.bw-main{display:block;min-height:56vh}
.bw-section{padding-block:clamp(40px,7vw,96px)}
.bw-sr{position:absolute;width:1px;height:1px;margin:-1px;padding:0;overflow:hidden;clip:rect(0 0 0 0);white-space:nowrap;border:0}

.bw-grid{display:grid;grid-template-columns:repeat(12,minmax(0,1fr));gap:clamp(16px,2vw,28px)}
.bw-col-3{grid-column:span 3}
.bw-col-4{grid-column:span 4}
.bw-col-5{grid-column:span 5}
.bw-col-6{grid-column:span 6}
.bw-col-7{grid-column:span 7}
.bw-col-8{grid-column:span 8}
.bw-col-9{grid-column:span 9}
.bw-col-12{grid-column:span 12}

.bw-rail-layout{display:grid;grid-template-columns:var(--bw-rail) minmax(0,1fr);gap:clamp(20px,3vw,44px);align-items:start}
.bw-rail{position:sticky;top:150px;align-self:start}
.bw-rail__list{display:flex;flex-direction:column;gap:14px}
.bw-rail__link{display:flex;align-items:center;gap:10px;font-size:11px;letter-spacing:.12em;color:var(--bw-text-faint);transition:color .16s var(--bw-ease)}
.bw-rail__link:hover{color:var(--bw-white)}
.bw-rail__link[aria-current="true"]{color:var(--bw-amber)}
.bw-rail__num{font-family:var(--bw-mono);font-variant-numeric:tabular-nums;font-size:11px;color:var(--bw-line-strong)}
.bw-rail__link[aria-current="true"] .bw-rail__num{color:var(--bw-amber)}

/* ---------- 5. 跳过链接 ---------- */
.bw-skip{
  position:absolute;left:12px;top:-72px;z-index:200;
  padding:10px 18px;background:var(--bw-amber);color:var(--bw-ink);
  font-size:13px;font-weight:700;letter-spacing:.08em;
  transition:top .18s var(--bw-ease);
}
.bw-skip:focus{top:12px}

/* ---------- 6. 头部：双层导航 ---------- */
.bw-header{position:sticky;top:0;z-index:80;background:var(--bw-charcoal)}

.bw-topbar{position:relative;background:var(--bw-asphalt)}
.bw-topbar__inner{display:flex;align-items:center;justify-content:space-between;gap:16px;min-height:58px;padding-block:10px}
.bw-topbar__rule{display:block;height:2px;background:linear-gradient(90deg,var(--bw-red) 0 34%,var(--bw-red-dark) 34% 56%,rgba(200,51,43,.26) 56% 100%)}

.bw-brand{display:inline-flex;align-items:center;gap:12px;min-width:0}
.bw-brand__mark{
  flex:0 0 auto;display:grid;place-items:center;
  width:36px;height:30px;background:var(--bw-red);color:var(--bw-white);
  transform:skewX(var(--bw-slant));
}
.bw-brand__mark i{
  font-style:normal;font-family:var(--bw-mono);font-size:13px;font-weight:700;
  letter-spacing:.04em;transform:skewX(12deg);
}
.bw-brand__text{display:flex;flex-direction:column;line-height:1.25;min-width:0}
.bw-brand__name{font-family:var(--bw-serif);font-size:17px;font-weight:700;letter-spacing:.02em;color:var(--bw-white);white-space:nowrap}
.bw-brand__tag{font-size:11px;letter-spacing:.16em;color:var(--bw-text-faint);white-space:nowrap}

.bw-topbar__tools{display:flex;align-items:center;gap:10px;flex:0 0 auto}
.bw-search{
  display:inline-flex;align-items:center;gap:8px;
  padding:7px 13px;border:1px solid var(--bw-line);
  font-size:12px;letter-spacing:.08em;color:var(--bw-text-faint);
  transition:border-color .18s var(--bw-ease),color .18s var(--bw-ease),background .18s var(--bw-ease);
}
.bw-search:hover,.bw-search:focus-visible{border-color:var(--bw-line-strong);color:var(--bw-white);background:rgba(74,127,165,.10)}
.bw-search__icon{position:relative;display:inline-block;width:11px;height:11px;border:1.5px solid currentColor;border-radius:50%;flex:0 0 auto}
.bw-search__icon::after{content:"";position:absolute;top:9px;left:8px;width:1.5px;height:5px;background:currentColor;transform:rotate(-45deg);transform-origin:top center}
.bw-search__text{white-space:nowrap}

.bw-member{
  display:inline-flex;align-items:center;gap:8px;
  padding:7px 14px;border:1px solid var(--bw-red);
  background:rgba(200,51,43,.14);color:var(--bw-white);
  font-size:12px;letter-spacing:.14em;white-space:nowrap;
  transition:background .18s var(--bw-ease),border-color .18s var(--bw-ease);
}
.bw-member:hover,.bw-member:focus-visible{background:var(--bw-red);border-color:var(--bw-red)}
.bw-member__dot{width:6px;height:6px;border-radius:50%;background:var(--bw-green);box-shadow:0 0 0 3px rgba(47,122,79,.24);flex:0 0 auto}

.bw-navbar{position:relative;background:var(--bw-charcoal);border-bottom:1px solid var(--bw-line)}
.bw-navbar__inner{display:flex;align-items:center;justify-content:space-between;gap:20px;min-height:60px}
.bw-navbar__end{display:flex;align-items:center;gap:12px;flex:0 0 auto}

.bw-nav{position:static}
.bw-nav__list{display:flex;align-items:center;gap:2px}
.bw-nav__item{display:block}
.bw-nav__link{
  position:relative;isolation:isolate;
  display:inline-flex;align-items:center;
  padding:10px 16px;font-size:14px;letter-spacing:.06em;color:var(--bw-text-dim);
  transition:color .16s var(--bw-ease);
}
.bw-nav__link::before{
  content:"";position:absolute;inset:7px 3px;z-index:-1;
  background:var(--bw-red);
  transform:skewX(var(--bw-slant)) scaleX(.6);
  opacity:0;
  transition:transform .22s var(--bw-ease),opacity .22s var(--bw-ease);
}
.bw-nav__link::after{
  content:"";position:absolute;left:50%;right:50%;bottom:3px;height:1px;
  background:var(--bw-amber);
  transition:left .22s var(--bw-ease),right .22s var(--bw-ease);
}
.bw-nav__link:hover,.bw-nav__link:focus-visible{color:var(--bw-white)}
.bw-nav__link:hover::before{opacity:.26;transform:skewX(var(--bw-slant)) scaleX(1)}
.bw-nav__link:hover::after{left:16px;right:16px}
.bw-nav__link[aria-current="page"]{color:var(--bw-white);font-weight:500}
.bw-nav__link[aria-current="page"]::before{opacity:1;transform:skewX(var(--bw-slant)) scaleX(1)}
.bw-nav__link[aria-current="page"]::after{display:none}

.bw-nav__cta{
  position:relative;isolation:isolate;
  display:inline-flex;align-items:center;
  padding:10px 20px;font-size:13px;letter-spacing:.10em;color:var(--bw-white);
}
.bw-nav__cta::before{
  content:"";position:absolute;inset:0;z-index:-1;
  background:var(--bw-red);
  transform:skewX(var(--bw-slant)) scaleX(.84);
  transition:transform .22s var(--bw-ease),background .18s var(--bw-ease);
}
.bw-nav__cta:hover::before,.bw-nav__cta:focus-visible::before{transform:skewX(var(--bw-slant)) scaleX(1);background:var(--bw-red-dark)}

.bw-navtoggle{
  display:none;align-items:center;gap:9px;
  padding:9px 13px;border:1px solid var(--bw-line-strong);color:var(--bw-white);
  font-size:12px;letter-spacing:.16em;
  transition:border-color .18s var(--bw-ease),background .18s var(--bw-ease);
}
.bw-navtoggle:hover{border-color:var(--bw-red);background:rgba(200,51,43,.14)}
.bw-navtoggle__bars{display:grid;gap:3px;width:16px;flex:0 0 auto}
.bw-navtoggle__bars i{display:block;height:2px;background:currentColor;transition:transform .2s var(--bw-ease),opacity .2s var(--bw-ease)}
.bw-header[data-open] .bw-navtoggle__bars i:nth-child(1){transform:translateY(5px) rotate(45deg)}
.bw-header[data-open] .bw-navtoggle__bars i:nth-child(2){opacity:0}
.bw-header[data-open] .bw-navtoggle__bars i:nth-child(3){transform:translateY(-5px) rotate(-45deg)}
.bw-navtoggle__text{white-space:nowrap}

.bw-progress{
  position:absolute;left:0;bottom:-1px;height:2px;width:0;z-index:3;
  background:linear-gradient(90deg,var(--bw-amber),var(--bw-red));
  transition:width .12s linear;
}

/* ---------- 7. 页脚 ---------- */
.bw-footer{
  position:relative;
  margin-top:clamp(48px,8vw,120px);
  background:var(--bw-asphalt);
  border-top:2px solid var(--bw-red);
  background-image:repeating-linear-gradient(0deg,rgba(74,127,165,.05) 0 1px,transparent 1px 90px);
}
.bw-footer__grid{
  display:grid;
  grid-template-columns:1.5fr 1fr 1fr 1.25fr;
  gap:clamp(24px,3vw,48px);
  padding-block:clamp(40px,5vw,72px);
}
.bw-footer__col{min-width:0}
.bw-footer__brand{font-family:var(--bw-serif);font-size:22px;font-weight:700;color:var(--bw-white)}
.bw-footer__tag{margin-top:6px;font-size:11px;letter-spacing:.18em;color:var(--bw-amber)}
.bw-footer__note{margin-top:14px;max-width:36ch;font-size:13px;line-height:1.85;color:var(--bw-text-faint)}
.bw-footer__title{
  margin-bottom:12px;padding-bottom:10px;
  border-bottom:1px solid var(--bw-line-soft);
  font-size:11px;font-weight:700;letter-spacing:.18em;color:var(--bw-blue);text-transform:uppercase;
}
.bw-footer__list li+li{margin-top:9px}
.bw-footer__list a{position:relative;font-size:13.5px;color:var(--bw-text-dim);transition:color .16s var(--bw-ease)}
.bw-footer__list a::after{
  content:"";position:absolute;left:50%;right:50%;bottom:-3px;height:1px;background:var(--bw-red);
  transition:left .22s var(--bw-ease),right .22s var(--bw-ease);
}
.bw-footer__list a:hover,.bw-footer__list a:focus-visible{color:var(--bw-white)}
.bw-footer__list a:hover::after{left:0;right:0}
.bw-footer__contact{font-size:13px;line-height:1.9;color:var(--bw-text-dim)}
.bw-footer__contact strong{font-weight:500;color:var(--bw-white);word-break:break-all}
.bw-footer__contact p+p{margin-top:2px}

.bw-copy{
  display:inline-flex;align-items:center;gap:8px;
  margin-top:12px;padding:8px 15px;
  border:1px solid var(--bw-line-strong);color:var(--bw-white);
  font-size:12px;letter-spacing:.10em;
  transition:border-color .18s var(--bw-ease),background .18s var(--bw-ease),color .18s var(--bw-ease);
}
.bw-copy:hover,.bw-copy:focus-visible{border-color:var(--bw-green);background:rgba(47,122,79,.18);color:var(--bw-green-ink)}
.bw-copy__hint{margin-top:8px;font-size:12px;letter-spacing:.06em;color:var(--bw-green-ink)}
.bw-copy__hint:empty{display:none}

.bw-footer__legal{
  display:flex;flex-wrap:wrap;align-items:center;justify-content:space-between;gap:12px 28px;
  padding-block:20px;border-top:1px solid var(--bw-line-soft);
  font-size:12px;color:var(--bw-text-faint);
}
.bw-footer__legal-links{display:flex;flex-wrap:wrap;gap:22px}
.bw-footer__legal a{transition:color .16s var(--bw-ease)}
.bw-footer__legal a:hover,.bw-footer__legal a:focus-visible{color:var(--bw-white)}

.bw-ticker{border-top:1px solid var(--bw-line-soft);background:var(--bw-charcoal);padding-block:12px}
.bw-ticker__inner{display:flex;flex-wrap:wrap;align-items:center;gap:16px 24px;justify-content:space-between}
.bw-ticker__meta{font-family:var(--bw-mono);font-variant-numeric:tabular-nums;font-size:11px;letter-spacing:.10em;color:var(--bw-text-faint)}
.bw-ticker__scale{
  flex:1 1 200px;min-width:110px;height:8px;
  background-image:
    repeating-linear-gradient(90deg,var(--bw-tick) 0 1px,transparent 1px 70px),
    repeating-linear-gradient(90deg,rgba(74,127,165,.24) 0 1px,transparent 1px 14px);
  background-size:70px 8px,14px 5px;
  background-position:left bottom,left bottom;
  background-repeat:repeat-x;
}

/* ---------- 8. 文字系统 ---------- */
.bw-h1{font-family:var(--bw-serif);font-weight:700;font-size:clamp(34px,5.4vw,64px);line-height:1.08;letter-spacing:-.01em}
.bw-h2{font-family:var(--bw-serif);font-weight:700;font-size:clamp(26px,3.4vw,40px);line-height:1.15;letter-spacing:-.01em}
.bw-h3{font-family:var(--bw-serif);font-weight:700;font-size:clamp(20px,2.2vw,28px);line-height:1.3}
.bw-h4{font-size:20px;font-weight:500;line-height:1.4;letter-spacing:.01em}
.bw-lede{max-width:62ch;font-size:clamp(16px,1.5vw,19px);line-height:1.8;color:var(--bw-text-dim)}
.bw-body{max-width:68ch;font-size:16px;line-height:1.85;color:var(--bw-text-dim)}
.bw-body p+p{margin-top:1.1em}
.bw-eyebrow{display:inline-flex;align-items:center;gap:9px;font-size:11px;letter-spacing:.18em;text-transform:uppercase;color:var(--bw-blue)}
.bw-eyebrow::before{content:"";display:inline-block;width:14px;height:2px;background:var(--bw-red);flex:0 0 auto}
.bw-label{font-size:11px;font-weight:700;letter-spacing:.16em;text-transform:uppercase;color:var(--bw-text-faint)}
.bw-num{font-family:var(--bw-mono);font-variant-numeric:tabular-nums;letter-spacing:-.01em}

/* ---------- 9. 按钮 / 标签 / 芯片 ---------- */
.bw-btn{
  position:relative;isolation:isolate;
  display:inline-flex;align-items:center;gap:10px;
  padding:12px 24px;border:1px solid var(--bw-line-strong);
  font-size:14px;font-weight:500;letter-spacing:.08em;color:var(--bw-white);
  transition:color .18s var(--bw-ease),border-color .18s var(--bw-ease);
}
.bw-btn::before{
  content:"";position:absolute;inset:0;z-index:-1;background:var(--bw-red);
  transform:skewX(var(--bw-slant)) scaleX(0);transform-origin:left center;
  transition:transform .22s var(--bw-ease),background .18s var(--bw-ease);
}
.bw-btn:hover::before,.bw-btn:focus-visible::before{transform:skewX(var(--bw-slant)) scaleX(1)}
.bw-btn--red{background:var(--bw-red);border-color:var(--bw-red)}
.bw-btn--red::before{background:var(--bw-red-dark)}
.bw-btn--ghost{border-color:var(--bw-line)}
.bw-btn--sm{padding:9px 16px;font-size:12px;letter-spacing:.1em}
.bw-btn--num{font-family:var(--bw-mono);font-variant-numeric:tabular-nums}

.bw-tag{display:inline-flex;align-items:center;gap:6px;padding:3px 10px;border:1px solid var(--bw-line-strong);font-size:11px;letter-spacing:.12em;color:var(--bw-text-dim)}
.bw-tag--green{border-color:var(--bw-green);background:rgba(47,122,79,.16);color:var(--bw-green-ink)}
.bw-tag--amber{border-color:var(--bw-amber);background:rgba(242,178,51,.12);color:var(--bw-amber)}
.bw-tag--red{border-color:var(--bw-red);background:rgba(200,51,43,.18);color:#F0A09B}

.bw-chip{
  display:inline-flex;align-items:center;gap:8px;
  padding:8px 14px;border:1px solid var(--bw-line);
  font-size:12px;letter-spacing:.12em;color:var(--bw-text-dim);
  transition:background .18s var(--bw-ease),border-color .18s var(--bw-ease),color .18s var(--bw-ease);
}
.bw-chip:hover{border-color:var(--bw-line-strong);color:var(--bw-white)}
.bw-chip[aria-pressed="true"],.bw-chip.is-active{background:var(--bw-red);border-color:var(--bw-red);color:var(--bw-white)}

/* ---------- 10. 面板 / 数据 / 媒体 / 折叠 / 面包屑 ---------- */
.bw-panel{
  --cut:var(--bw-cut);
  --pad:clamp(20px,2.6vw,32px);
  position:relative;isolation:isolate;
  padding:var(--pad);
  background:var(--bw-line);
  clip-path:polygon(0 0,calc(100% - var(--cut)) 0,100% var(--cut),100% 100%,var(--cut) 100%,0 calc(100% - var(--cut)));
  transition:background .2s var(--bw-ease);
}
.bw-panel::before{
  content:"";position:absolute;inset:1px;z-index:-1;
  background:var(--bw-asphalt);
  clip-path:polygon(0 0,calc(100% - var(--cut)) 0,100% var(--cut),100% 100%,var(--cut) 100%,0 calc(100% - var(--cut)));
}
.bw-panel:hover{background:var(--bw-line-strong)}
.bw-panel--concrete{background:rgba(27,29,33,.28);color:var(--bw-ink)}
.bw-panel--concrete::before{background:var(--bw-concrete)}
.bw-panel--concrete .bw-body,.bw-panel--concrete .bw-lede{color:rgba(27,29,33,.78)}
.bw-panel--concrete .bw-label{color:rgba(27,29,33,.55)}
.bw-panel--red{background:rgba(242,178,51,.55)}
.bw-panel--red::before{background:var(--bw-red-dark)}
.bw-panel--flat{--cut:0px}

.bw-stat{display:flex;flex-direction:column;gap:4px;padding-left:14px;border-left:2px solid var(--bw-line-strong)}
.bw-stat__label{font-size:11px;letter-spacing:.16em;color:var(--bw-text-faint)}
.bw-stat__value{font-family:var(--bw-mono);font-variant-numeric:tabular-nums;font-size:clamp(24px,3vw,32px);line-height:1.1;color:var(--bw-amber)}
.bw-stat--green .bw-stat__value{color:var(--bw-green-ink)}
.bw-stat--plain .bw-stat__value{color:var(--bw-white)}

.bw-table{width:100%;font-size:14px}
.bw-table caption{padding-bottom:10px;text-align:left;font-size:11px;letter-spacing:.16em;color:var(--bw-blue)}
.bw-table th,.bw-table td{padding:12px 14px;text-align:left;border-bottom:1px solid var(--bw-line-soft)}
.bw-table thead th{background:rgba(142,31,26,.55);font-size:11px;font-weight:700;letter-spacing:.14em;color:var(--bw-white)}
.bw-table tbody tr{transition:background .18s var(--bw-ease)}
.bw-table tbody tr:hover{background:rgba(74,127,165,.10)}
.bw-table td.bw-num,.bw-table th.bw-num{font-family:var(--bw-mono);font-variant-numeric:tabular-nums}
.bw-table tr[data-active="true"]{background:rgba(242,178,51,.16)}
.bw-table--light{color:var(--bw-ink)}
.bw-table--light th,.bw-table--light td{border-bottom-color:rgba(27,29,33,.14)}
.bw-table--light thead th{background:var(--bw-red-dark);color:var(--bw-white)}
.bw-table--light tbody tr:hover{background:rgba(27,29,33,.06)}

.bw-media{display:block;margin:0}
.bw-media__frame{
  position:relative;width:100%;aspect-ratio:16/9;overflow:hidden;
  background-color:var(--bw-asphalt);
  background-image:
    repeating-linear-gradient(0deg,rgba(74,127,165,.12) 0 1px,transparent 1px 28px),
    repeating-linear-gradient(90deg,rgba(74,127,165,.12) 0 1px,transparent 1px 28px),
    linear-gradient(135deg,rgba(74,127,165,.16),rgba(20,22,26,0) 62%);
  clip-path:polygon(0 0,calc(100% - var(--bw-cut)) 0,100% var(--bw-cut),100% 100%,var(--bw-cut) 100%,0 calc(100% - var(--bw-cut)));
}
.bw-media__frame img,.bw-media__frame svg,.bw-media__frame video{width:100%;height:100%;object-fit:cover}
.bw-media__cap{display:flex;flex-wrap:wrap;justify-content:space-between;gap:10px;margin-top:10px;font-family:var(--bw-mono);font-size:11px;letter-spacing:.08em;color:var(--bw-text-faint)}
.bw-media--4x3 .bw-media__frame{aspect-ratio:4/3}
.bw-media--3x2 .bw-media__frame{aspect-ratio:3/2}
.bw-media--1x1 .bw-media__frame{aspect-ratio:1/1}
.bw-media--21x9 .bw-media__frame{aspect-ratio:21/9}
.bw-media--tall .bw-media__frame{aspect-ratio:3/4}

.bw-fold{border-top:1px solid var(--bw-line-soft);transition:padding-left .18s ease-out}
.bw-fold summary{
  position:relative;padding:16px 0 16px 24px;
  list-style:none;cursor:pointer;font-size:15px;color:var(--bw-white);
}
.bw-fold summary::-webkit-details-marker{display:none}
.bw-fold summary::before{content:"";position:absolute;left:0;top:23px;width:11px;height:1.5px;background:var(--bw-amber)}
.bw-fold summary::after{content:"";position:absolute;left:4.5px;top:18px;width:1.5px;height:11px;background:var(--bw-amber);transition:transform .18s ease-out}
.bw-fold[open] summary::after{transform:scaleY(0)}
.bw-fold[open]{border-left:2px solid var(--bw-red);padding-left:16px}
.bw-fold[open] summary{color:var(--bw-amber)}
.bw-fold__body{padding:0 0 18px 24px;font-size:14px;line-height:1.85;color:var(--bw-text-dim)}

.bw-crumbs{display:flex;flex-wrap:wrap;align-items:center;gap:10px;padding-block:18px;font-family:var(--bw-mono);font-size:11px;letter-spacing:.08em;color:var(--bw-text-faint)}
.bw-crumbs a{transition:color .16s var(--bw-ease)}
.bw-crumbs a:hover,.bw-crumbs a:focus-visible{color:var(--bw-white)}
.bw-crumbs__sep{color:var(--bw-line-strong)}
.bw-crumbs [aria-current="page"]{color:var(--bw-amber)}

/* ---------- 11. 显现动效 ---------- */
[data-reveal]{opacity:0;transform:translateY(14px);transition:opacity .55s var(--bw-ease),transform .55s var(--bw-ease)}
[data-reveal].is-in{opacity:1;transform:none}

/* ---------- 12. 响应式 ---------- */
@media (max-width:1024px){
  .bw-col-3,.bw-col-4,.bw-col-5{grid-column:span 6}
  .bw-col-7,.bw-col-8,.bw-col-9{grid-column:span 12}
  .bw-rail-layout{grid-template-columns:minmax(0,1fr)}
  .bw-rail{display:none}
  .bw-footer__grid{grid-template-columns:1fr 1fr}
  .bw-footer__col--brand{grid-column:1 / -1}
}

@media (max-width:900px){
  .bw-navbar__inner{min-height:56px}
  .bw-navtoggle{display:inline-flex}
  .bw-nav{
    position:absolute;left:0;right:0;top:100%;z-index:6;
    background:var(--bw-asphalt);
    border-top:1px solid var(--bw-line);
    border-bottom:1px solid var(--bw-line);
    max-height:0;overflow:hidden;
    transition:max-height .26s ease-out;
  }
  .bw-header[data-open] .bw-nav{max-height:min(72vh,540px);overflow-y:auto}
  .bw-nav__list{flex-direction:column;align-items:stretch;gap:0;padding:6px 0 14px}
  .bw-nav__item{border-bottom:1px solid var(--bw-line-soft)}
  .bw-nav__item:last-child{border-bottom:0}
  .bw-nav__link{width:100%;padding:15px 20px;font-size:15px;justify-content:flex-start}
  .bw-nav__link::before{inset:10px 12px}
  .bw-nav__link::after{display:none}
  .bw-nav__list .bw-nav__link[aria-current="page"]{padding-left:20px}
}

@media (max-width:720px){
  .bw-col-3,.bw-col-4,.bw-col-5,.bw-col-6,.bw-col-7,.bw-col-8,.bw-col-9{grid-column:span 12}
  .bw-footer__grid{grid-template-columns:1fr}
  .bw-footer__legal{justify-content:flex-start}
  .bw-media--21x9 .bw-media__frame{aspect-ratio:16/9}
}

@media (max-width:640px){
  .bw-brand__tag{display:none}
  .bw-search{display:none}
  .bw-brand__name{font-size:16px}
  .bw-topbar__inner{min-height:52px}
  .bw-nav__cta{padding:9px 14px;font-size:12px;letter-spacing:.06em}
  .bw-ticker__meta{font-size:10px}
}

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