/* ============================================================
   九博体育中心 · 共享样式表 /assets/site.css
   1 Reset · 2 变量 · 3 中文排版 · 4 布局容器与网格
   5 页头 · 6 页脚 · 7 通用组件 · 8 动效与可访问性
   ============================================================ */

/* ---------- 1 Reset ---------- */
*,*::before,*::after{box-sizing:border-box}
html{-webkit-text-size-adjust:100%;scroll-behavior:smooth}
body,h1,h2,h3,h4,h5,h6,p,figure,blockquote,dl,dd{margin:0}
ul,ol{margin:0;padding:0;list-style:none}
img,picture,svg,video{display:block;max-width:100%}
button,input,select,textarea{font:inherit;color:inherit}
button{background:none;border:0;cursor:pointer}
a{color:inherit;text-decoration:none}
table{border-collapse:collapse;border-spacing:0}
[hidden]{display:none!important}
:focus-visible{outline:2px solid #1FF3D6;outline-offset:2px}
::selection{background:#1FF3D6;color:#05081A}

/* ---------- 2 变量 ---------- */
:root{
  --ink-900:#05081A;
  --ink-800:#0B1030;
  --ink-700:#171F45;
  --line:#2C3568;
  --line-soft:rgba(44,53,104,.55);
  --cyan:#1FF3D6;
  --flame:#FF5A2B;
  --gold:#C9A24A;
  --fog:#E9EDFB;
  --fog-soft:rgba(233,237,251,.82);
  --mist:#8D96B8;
  --amber:#FFB020;

  --shell:1280px;
  --gutter:clamp(16px,4vw,40px);
  --cut:18px;
  --cut-sm:10px;

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

  --ease:cubic-bezier(0.22,1,0.36,1);
  --dur:.32s;
}

/* ---------- 3 中文排版 ---------- */
body{
  min-height:100vh;
  font-family:var(--font-body);
  font-size:clamp(15px,.35vw + 13.6px,17px);
  line-height:1.7;
  letter-spacing:.01em;
  color:var(--fog);
  background-color:var(--ink-800);
  background-image:
    radial-gradient(900px 420px at 6% -10%,rgba(31,243,214,.10),transparent 70%),
    radial-gradient(760px 400px at 98% 3%,rgba(255,90,43,.11),transparent 72%),
    linear-gradient(180deg,#0B1030 0%,#080C24 62%,#05081A 100%);
  background-repeat:no-repeat;
  -webkit-font-smoothing:antialiased;
}
body::before{
  content:"";
  position:fixed;
  inset:0;
  z-index:-1;
  pointer-events:none;
  background-image:repeating-linear-gradient(0deg,rgba(233,237,251,.032) 0 1px,transparent 1px 5px);
}
h1,h2,h3,h4{font-weight:900;letter-spacing:-.02em;line-height:1.2;color:var(--fog)}
p{color:var(--fog-soft)}
strong{color:var(--fog);font-weight:800}
[data-section],section[id],h2[id],h3[id]{scroll-margin-top:150px}

.visually-hidden{position:absolute!important;width:1px;height:1px;padding:0;margin:-1px;overflow:hidden;clip:rect(0 0 0 0);white-space:nowrap;border:0}
.mono{font-family:var(--font-mono);font-variant-numeric:tabular-nums;font-weight:700;letter-spacing:.02em}
.num{font-family:var(--font-mono);font-variant-numeric:tabular-nums;font-weight:800;letter-spacing:-.02em;line-height:1.05;color:var(--fog)}
.num--xl{font-size:clamp(34px,5vw,52px)}
.num--cyan{color:var(--cyan)}
.num--gold{color:var(--gold)}
.num--flame{color:var(--flame)}
.num--amber{color:var(--amber)}
.eyebrow{display:inline-flex;align-items:center;gap:10px;font-family:var(--font-mono);font-size:12px;font-weight:700;letter-spacing:.18em;text-transform:uppercase;color:var(--cyan)}
.eyebrow::before{content:"";width:28px;height:1px;background:var(--cyan)}
.anno{display:inline-block;font-family:var(--font-mono);font-size:11px;letter-spacing:.14em;color:var(--mist)}
.anno--vertical{writing-mode:vertical-rl;text-orientation:mixed;letter-spacing:.3em}
.rule{height:1px;border:0;margin:0;background:var(--line)}
.rule--slant{height:2px;background:linear-gradient(90deg,var(--cyan),rgba(31,243,214,0) 62%)}

/* ---------- 4 布局容器与网格 ---------- */
.shell{width:100%;max-width:var(--shell);margin-inline:auto;padding-inline:var(--gutter)}
.section{padding-block:clamp(56px,7vw,104px)}
.section--tight{padding-block:clamp(32px,4vw,56px)}
.section--band{
  background:linear-gradient(180deg,rgba(23,31,69,.62),rgba(23,31,69,.14));
  border-block:1px solid var(--line);
}
.grid{display:grid;gap:clamp(16px,2vw,28px)}
.grid--tight{gap:12px}
.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))}
.grid--split{grid-template-columns:minmax(0,5fr) minmax(0,7fr)}
.grid--split-rev{grid-template-columns:minmax(0,7fr) minmax(0,5fr)}
@media (max-width:1080px){
  .grid--4{grid-template-columns:repeat(2,minmax(0,1fr))}
}
@media (max-width:980px){
  .grid--3{grid-template-columns:repeat(2,minmax(0,1fr))}
  .grid--split,.grid--split-rev{grid-template-columns:minmax(0,1fr)}
}
@media (max-width:640px){
  .grid--2,.grid--3,.grid--4{grid-template-columns:minmax(0,1fr)}
}
.section-head{max-width:62ch;margin-bottom:clamp(24px,3vw,44px)}
.section-head__index{display:block;margin-bottom:10px;font-family:var(--font-mono);font-size:12px;font-weight:700;letter-spacing:.2em;color:var(--gold)}
.section-head__title{font-size:clamp(24px,3.2vw,34px)}
.section-head__lead{margin-top:12px;font-size:15px;color:var(--mist)}
.prose{max-width:46rem}
.prose p{margin-bottom:1.2em}
.prose h2{font-size:clamp(22px,2.6vw,34px);margin:2em 0 .6em}
.prose h3{font-size:18px;margin:1.6em 0 .5em}
.prose ul{margin:0 0 1.2em}
.prose li{position:relative;padding-left:18px;margin-bottom:.5em;color:var(--fog-soft)}
.prose li::before{content:"";position:absolute;left:0;top:.78em;width:8px;height:1px;background:var(--cyan)}

/* ---------- 5 页头 ---------- */
.skip-link{
  position:absolute;left:16px;top:-64px;z-index:120;
  padding:10px 18px;background:var(--cyan);color:var(--ink-900);
  font-size:14px;font-weight:800;transition:top .2s var(--ease);
}
.skip-link:focus{top:14px}

.site-header{
  position:sticky;top:0;z-index:80;
  background:rgba(11,16,48,.94);
  border-bottom:1px solid var(--line);
  -webkit-backdrop-filter:blur(14px);
  backdrop-filter:blur(14px);
}
.scroll-progress{position:absolute;left:0;right:0;bottom:-1px;height:2px;background:rgba(44,53,104,.6);overflow:hidden}
.scroll-progress__bar{
  display:block;width:100%;height:100%;
  background:linear-gradient(90deg,var(--cyan),var(--flame));
  transform:scaleX(0);transform-origin:0 50%;
  transition:transform .12s linear;
}

.header-top__inner{
  display:flex;align-items:center;gap:clamp(12px,2vw,28px);
  padding-block:clamp(12px,1.6vw,20px);
  transition:padding .3s var(--ease);
}
.site-header.is-condensed .header-top__inner{padding-block:8px}

.brand{display:inline-flex;align-items:center;gap:12px;flex:0 0 auto}
.brand__mark{
  width:40px;height:40px;flex:0 0 auto;display:grid;place-items:center;
  transform:rotate(45deg);
  border:1px solid rgba(201,162,74,.75);
  background:linear-gradient(135deg,rgba(201,162,74,.22),rgba(31,243,214,.07));
}
.brand__mark-core{transform:rotate(-45deg);font-family:var(--font-mono);font-size:16px;font-weight:800;line-height:1;color:var(--gold)}
.brand__text{display:flex;flex-direction:column;gap:2px;min-width:0}
.brand__name{font-size:clamp(16px,1.6vw,19px);font-weight:900;letter-spacing:-.01em;color:var(--fog)}
.brand__subline{
  max-height:24px;overflow:hidden;
  font-size:12px;letter-spacing:.04em;color:var(--mist);
  transition:max-height .3s var(--ease),opacity .3s var(--ease);
}
.site-header.is-condensed .brand__subline{max-height:0;opacity:0}

.header-status{display:none;align-items:center;gap:8px;font-family:var(--font-mono);font-size:12px;letter-spacing:.08em;color:var(--mist)}
.header-status__dot{width:7px;height:7px;flex:0 0 auto;background:var(--cyan);box-shadow:0 0 0 3px rgba(31,243,214,.16);animation:statusPulse 2.4s var(--ease) infinite}
.header-status__label{white-space:nowrap}
@keyframes statusPulse{0%,100%{opacity:1}50%{opacity:.3}}
@media (min-width:1100px){.header-status{display:inline-flex;margin-inline:auto}}

.header-aside{display:flex;align-items:center;gap:clamp(8px,1.4vw,18px);margin-left:auto}
.utility-link{
  padding:8px 4px;font-size:13px;font-weight:600;color:var(--mist);
  border-bottom:1px solid transparent;transition:color .24s var(--ease),border-color .24s var(--ease);
}
.utility-link:hover{color:var(--cyan);border-bottom-color:var(--cyan)}
@media (max-width:760px){.utility-link{display:none}}

.nav-toggle{
  display:none;width:44px;height:44px;place-items:center;
  border:1px solid var(--line);background:rgba(23,31,69,.7);
  transition:border-color .24s var(--ease),background-color .24s var(--ease);
}
.nav-toggle:hover{border-color:var(--cyan);background:rgba(31,243,214,.08)}
.nav-toggle__bars{position:relative;display:block;width:18px;height:12px}
.nav-toggle__bars span{position:absolute;left:0;width:100%;height:2px;background:var(--fog);transition:transform .3s var(--ease),opacity .2s var(--ease),top .3s var(--ease)}
.nav-toggle__bars span:nth-child(1){top:0}
.nav-toggle__bars span:nth-child(2){top:5px}
.nav-toggle__bars span:nth-child(3){top:10px}
.nav-toggle[aria-expanded="true"] .nav-toggle__bars span:nth-child(1){top:5px;transform:rotate(45deg)}
.nav-toggle[aria-expanded="true"] .nav-toggle__bars span:nth-child(2){opacity:0}
.nav-toggle[aria-expanded="true"] .nav-toggle__bars span:nth-child(3){top:5px;transform:rotate(-45deg)}

.header-nav{border-top:1px solid var(--line);background:rgba(5,8,26,.45)}
.nav{position:relative}
.nav__list{
  display:flex;align-items:stretch;gap:clamp(4px,1vw,10px);
  overflow-x:auto;scroll-snap-type:x proximity;
  padding-block:8px;
  scrollbar-width:thin;scrollbar-color:var(--line) transparent;
  -webkit-overflow-scrolling:touch;
}
.nav__list::-webkit-scrollbar{height:4px}
.nav__list::-webkit-scrollbar-thumb{background:var(--line)}
.nav__item{flex:0 0 auto;scroll-snap-align:start}
.nav__link{
  display:flex;align-items:center;gap:8px;height:100%;
  padding:10px 14px;white-space:nowrap;
  font-size:14px;font-weight:700;color:var(--mist);
  border:1px solid transparent;
  transition:color .24s var(--ease),background-color .24s var(--ease),border-color .24s var(--ease),box-shadow .24s var(--ease);
}
.nav__index{font-family:var(--font-mono);font-size:11px;font-weight:700;letter-spacing:.06em;color:var(--line);transition:color .24s var(--ease)}
.nav__text{white-space:nowrap}
.nav__link:hover{color:var(--fog);border-color:var(--line);background:rgba(31,243,214,.06)}
.nav__link:hover .nav__index{color:var(--cyan)}
.nav__link.is-current{color:var(--fog);box-shadow:inset 0 -2px 0 var(--cyan)}
.nav__link.is-current .nav__index{color:var(--cyan)}
.nav__link[aria-current="page"]{background:var(--flame);border-color:var(--flame);color:#0B1030}
.nav__link[aria-current="page"] .nav__index{color:rgba(11,16,48,.6)}
.nav__link[aria-current="page"]:hover{background:#ff7047;border-color:#ff7047;color:#0B1030}

@media (max-width:900px){
  .nav-toggle{display:grid}
  .header-nav{
    display:grid;grid-template-rows:0fr;border-top-color:transparent;
    transition:grid-template-rows .34s var(--ease);
  }
  .site-header[data-open] .header-nav{grid-template-rows:1fr;border-top-color:var(--line)}
  .header-nav>.nav{min-height:0;overflow:hidden}
  .nav__list{flex-direction:column;gap:0;overflow:visible;padding-block:0}
  .nav__item{width:100%;border-bottom:1px solid var(--line-soft)}
  .nav__item:last-child{border-bottom:0}
  .nav__link{width:100%;padding:15px 2px;font-size:15px}
  .nav__link:hover,.nav__link.is-current{box-shadow:none;border-color:transparent;background:rgba(31,243,214,.06)}
  .nav__link[aria-current="page"]{background:transparent;border-color:transparent;color:var(--flame);box-shadow:none}
  .nav__link[aria-current="page"]::after{content:"";flex:1;height:1px;background:linear-gradient(90deg,rgba(255,90,43,.6),transparent)}
  .nav__link[aria-current="page"]:hover{background:rgba(255,90,43,.08)}
}

/* ---------- 6 页脚 ---------- */
.site-footer{
  position:relative;margin-top:clamp(56px,7vw,110px);
  background:var(--ink-900);
  border-top:1px solid var(--line);
  color:var(--mist);
}
.site-footer::before{
  content:"";position:absolute;top:0;left:0;
  width:min(460px,64%);height:1px;
  background:linear-gradient(90deg,var(--cyan),rgba(31,243,214,0));
}
.footer__main{
  display:grid;grid-template-columns:minmax(0,4fr) minmax(0,8fr);
  gap:clamp(28px,4vw,64px);
  padding-block:clamp(40px,5vw,72px);
}
.footer__brand{display:flex;flex-direction:column;align-items:flex-start;gap:16px}
.footer__tagline{max-width:34ch;font-size:13px;line-height:1.85;color:var(--mist)}
.footer__cols{display:grid;grid-template-columns:repeat(3,minmax(0,1fr));gap:clamp(18px,2.4vw,32px)}
.footer__col{min-width:0}
.footer__title{display:block;margin-bottom:14px;font-family:var(--font-mono);font-size:12px;font-weight:700;letter-spacing:.16em;color:var(--gold)}
.footer__list{display:flex;flex-direction:column;gap:10px}
.footer__link{display:inline-block;font-size:14px;color:var(--mist);transition:color .24s var(--ease),transform .24s var(--ease)}
.footer__link:hover{color:var(--cyan);transform:translateX(2px)}
.footer__link[aria-current="page"]{color:var(--fog);box-shadow:inset 0 -1px 0 var(--gold)}
.footer__bottom{
  display:flex;flex-wrap:wrap;align-items:center;justify-content:space-between;gap:12px 24px;
  padding-block:20px;border-top:1px solid var(--line-soft);
}
.footer__contact{font-family:var(--font-mono);font-size:12.5px;color:var(--mist);word-break:break-word}
.footer__legal{font-family:var(--font-mono);font-size:12px;letter-spacing:.06em;color:var(--mist)}
.to-top{
  display:inline-flex;align-items:center;gap:8px;
  padding:9px 16px;font-size:13px;font-weight:700;color:var(--fog);
  border:1px solid var(--line);background:rgba(23,31,69,.6);
  transition:border-color .24s var(--ease),color .24s var(--ease),background-color .24s var(--ease);
}
.to-top:hover{border-color:var(--cyan);color:var(--cyan);background:rgba(31,243,214,.07)}
@media (max-width:900px){
  .footer__main{grid-template-columns:minmax(0,1fr)}
}
@media (max-width:600px){
  .footer__cols{grid-template-columns:repeat(2,minmax(0,1fr))}
  .footer__bottom{flex-direction:column;align-items:flex-start}
}

/* ---------- 7 通用组件 ---------- */
.btn{
  display:inline-flex;align-items:center;justify-content:center;gap:8px;
  padding:12px 20px;font-size:14px;font-weight:800;line-height:1;letter-spacing:.02em;
  border:1px solid transparent;
  clip-path:polygon(0 0,calc(100% - var(--cut-sm)) 0,100% var(--cut-sm),100% 100%,var(--cut-sm) 100%,0 calc(100% - var(--cut-sm)));
  transition:background-color .24s var(--ease),color .24s var(--ease),border-color .24s var(--ease),box-shadow .24s var(--ease);
}
.btn--primary{background:var(--flame);color:#0B1030}
.btn--primary:hover{background:#ff7047;box-shadow:0 0 0 1px rgba(255,90,43,.5)}
.btn--ghost{border-color:var(--line);color:var(--fog);background:rgba(31,243,214,.05)}
.btn--ghost:hover{border-color:var(--cyan);color:var(--cyan);background:rgba(31,243,214,.1)}
.btn--quiet{padding-inline:0;color:var(--cyan);clip-path:none}
.btn--quiet:hover{color:var(--fog)}
.btn--sm{padding:9px 14px;font-size:13px}
.btn-row{display:flex;flex-wrap:wrap;align-items:center;gap:12px}

.panel{
  position:relative;padding:clamp(20px,2.4vw,32px);
  background:var(--ink-700);
  border:1px solid var(--line);
  clip-path:polygon(0 0,calc(100% - var(--cut)) 0,100% var(--cut),100% 100%,var(--cut) 100%,0 calc(100% - var(--cut)));
}
.panel--quiet{background:rgba(23,31,69,.55)}
.panel--accent{border-color:rgba(31,243,214,.45);background:linear-gradient(150deg,rgba(31,243,214,.10),rgba(23,31,69,.95))}
.panel__head{
  display:flex;align-items:baseline;justify-content:space-between;gap:16px;
  padding-bottom:14px;margin-bottom:18px;border-bottom:1px solid var(--line);
}
.panel__title{font-size:18px;font-weight:800;letter-spacing:-.01em;color:var(--fog)}
.panel__note{font-family:var(--font-mono);font-size:12px;letter-spacing:.08em;color:var(--mist)}

.card{
  display:flex;flex-direction:column;gap:10px;
  padding:clamp(16px,1.8vw,22px);
  background:linear-gradient(160deg,rgba(23,31,69,.96),rgba(11,16,48,.92));
  border:1px solid var(--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:border-color .24s var(--ease),background-color .24s var(--ease);
}
.card:hover{border-color:rgba(31,243,214,.5)}

.badge{
  display:inline-flex;align-items:center;gap:6px;
  padding:4px 10px;
  font-family:var(--font-mono);font-size:12px;font-weight:700;letter-spacing:.06em;
  color:var(--mist);background:rgba(11,16,48,.7);border:1px solid var(--line);
}
.badge--gold{color:var(--gold);border-color:rgba(201,162,74,.55);background:rgba(201,162,74,.1)}
.badge--cyan{color:var(--cyan);border-color:rgba(31,243,214,.45);background:rgba(31,243,214,.08)}
.badge--amber{color:var(--amber);border-color:rgba(255,176,32,.5);background:rgba(255,176,32,.09)}
.badge--flame{color:var(--flame);border-color:rgba(255,90,43,.5);background:rgba(255,90,43,.1)}

.stat{display:flex;flex-direction:column;gap:6px}
.stat__value{font-family:var(--font-mono);font-variant-numeric:tabular-nums;font-weight:800;font-size:clamp(24px,3vw,34px);line-height:1.05;color:var(--cyan)}
.stat__unit{margin-left:4px;font-size:12px;font-weight:600;color:var(--mist)}
.stat__label{font-size:12px;letter-spacing:.1em;color:var(--mist)}

.table-wrap{width:100%;overflow-x:auto;background:rgba(23,31,69,.5);border:1px solid var(--line)}
.data-table{width:100%;min-width:560px;font-size:14px}
.data-table caption{padding:14px 16px;text-align:left;font-family:var(--font-mono);font-size:12px;letter-spacing:.1em;color:var(--mist);border-bottom:1px solid var(--line)}
.data-table th,.data-table td{padding:12px 16px;text-align:left;border-bottom:1px solid var(--line-soft)}
.data-table thead th{font-size:12px;font-weight:700;letter-spacing:.1em;color:var(--mist);background:rgba(11,16,48,.75)}
.data-table tbody tr{transition:background-color .2s var(--ease)}
.data-table tbody tr:hover{background:rgba(31,243,214,.06)}
.data-table tbody tr:last-child th,.data-table tbody tr:last-child td{border-bottom:0}
.data-table .mono,.data-table [data-num]{font-family:var(--font-mono);font-variant-numeric:tabular-nums}

.tabs{
  display:inline-flex;gap:4px;padding:4px;
  background:rgba(11,16,48,.75);border:1px solid var(--line);
}
.tab{
  padding:8px 15px;font-size:13px;font-weight:700;color:var(--mist);
  transition:background-color .2s var(--ease),color .2s var(--ease);
}
.tab:hover{color:var(--fog)}
.tab[aria-selected="true"]{background:var(--flame);color:#0B1030}
[data-tab-panel]{padding-top:20px}

.fold{border:1px solid var(--line);background:rgba(23,31,69,.55)}
.fold + .fold{margin-top:10px}
.fold__summary{
  display:flex;align-items:center;justify-content:space-between;gap:16px;
  padding:14px 18px;font-size:15px;font-weight:700;color:var(--fog);
  cursor:pointer;list-style:none;
}
.fold__summary::-webkit-details-marker{display:none}
.fold__summary::after{content:"+";font-family:var(--font-mono);font-size:18px;color:var(--cyan)}
.fold[open] .fold__summary::after{content:"–"}
.fold__body{padding:0 18px 18px;font-size:14px;color:var(--mist)}

.meter{display:flex;flex-direction:column;gap:8px}
.meter__track{position:relative;height:8px;background:rgba(11,16,48,.9);border:1px solid var(--line);overflow:hidden}
.meter__bar{position:absolute;top:0;bottom:0;left:0;width:0;background:linear-gradient(90deg,var(--cyan),var(--flame));transition:width .5s var(--ease)}
.meter__scale{display:flex;justify-content:space-between;font-family:var(--font-mono);font-size:11px;color:var(--mist)}

.note{
  display:flex;gap:12px;
  padding:14px 16px;
  font-size:14px;color:var(--fog-soft);
  background:rgba(31,243,214,.06);
  border-left:2px solid var(--cyan);
}
.note--amber{background:rgba(255,176,32,.07);border-left-color:var(--amber)}

.tag-row{display:flex;flex-wrap:wrap;gap:8px}
.tag{
  padding:5px 11px;font-family:var(--font-mono);font-size:12px;letter-spacing:.04em;
  color:var(--mist);background:rgba(11,16,48,.7);border:1px solid var(--line);
  transition:color .2s var(--ease),border-color .2s var(--ease),background-color .2s var(--ease);
}
.tag:hover{color:var(--fog);border-color:var(--mist)}
.tag[aria-pressed="true"]{color:var(--cyan);border-color:var(--cyan);background:rgba(31,243,214,.1)}

.media-frame{
  position:relative;display:block;width:100%;overflow:hidden;
  background:linear-gradient(140deg,#171F45,#0B1030);
  border:1px solid var(--line);
  clip-path:polygon(0 0,calc(100% - var(--cut)) 0,100% var(--cut),100% 100%,var(--cut) 100%,0 calc(100% - var(--cut)));
}
.media-frame > img,.media-frame > picture > img{width:100%;height:100%;object-fit:cover}
.media-frame::after{
  content:"";position:absolute;inset:0;pointer-events:none;
  background:linear-gradient(180deg,rgba(5,8,26,0) 42%,rgba(5,8,26,.72) 100%);
}
.media-frame--hero{aspect-ratio:16/7}
.media-frame--16-9{aspect-ratio:16/9}
.media-frame--4-3{aspect-ratio:4/3}
.media-frame--1-1{aspect-ratio:1/1}
.media-frame--tall{aspect-ratio:3/4}
.media-frame__caption{
  position:absolute;left:0;bottom:0;z-index:2;
  padding:10px 14px;font-family:var(--font-mono);font-size:11px;letter-spacing:.12em;color:var(--mist);
}
@media (max-width:640px){.media-frame--hero{aspect-ratio:4/3}}

.breadcrumb{padding-top:18px}
.breadcrumb__list{display:flex;flex-wrap:wrap;align-items:center;gap:8px;font-family:var(--font-mono);font-size:12px;color:var(--mist)}
.breadcrumb__item{display:inline-flex;align-items:center;gap:8px;letter-spacing:.06em}
.breadcrumb__item:not(:first-child)::before{content:"/";color:var(--line)}
.breadcrumb__link{transition:color .2s var(--ease)}
.breadcrumb__link:hover{color:var(--cyan)}
.breadcrumb__current{color:var(--fog)}

/* ---------- 8 动效与可访问性 ---------- */
[data-reveal]{opacity:0;transform:translateY(16px);transition:opacity .4s var(--ease),transform .4s var(--ease)}
[data-reveal].is-visible{opacity:1;transform:none}

@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;transition:none}
  .scroll-progress__bar{transition:none}
}