/* =========================================================
   万能真人游艺 · /assets/site.css
   共享层：重置 / 变量 / 排版 / 头部 / 页脚 / 通用组件
   ========================================================= */

/* ---------- 1. 重置 ---------- */
*,*::before,*::after{box-sizing:border-box}
html{-webkit-text-size-adjust:100%;text-size-adjust:100%}
body,h1,h2,h3,h4,h5,p,figure,blockquote,dl,dd,ul,ol{margin:0}
ul[class],ol[class]{list-style:none;padding:0}
img,svg,video{max-width:100%}
img{display:block;height:auto}
button,input,select,textarea{font:inherit;color:inherit}
button{background:none;border:0;padding:0;cursor:pointer}
table{border-collapse:collapse;width:100%}
:focus-visible{outline:2px solid #7CF7E4;outline-offset:2px}

/* ---------- 2. 色彩与尺寸变量 ---------- */
:root{
  --bg:#05070D;
  --panel:#0D1219;
  --panel-2:#111A24;
  --panel-3:#16202C;
  --line:#1E2A38;
  --line-strong:#2C3E52;
  --text:#E8F1F8;
  --muted:#93A6B8;
  --ice:#45D6FF;
  --gold:#FFC24B;
  --rose:#FF3D7F;
  --cyan:#7CF7E4;
  --amber:#FF9A3C;
  --accent:#45D6FF;
  --accent-soft:rgba(69,214,255,.12);
  --accent-line:rgba(69,214,255,.45);
  --on-accent:#05070D;
  --font-display:"Barlow Condensed","Oswald","PingFang SC","Hiragino Sans GB","Microsoft YaHei","Noto Sans SC",sans-serif;
  --font-body:Inter,"PingFang SC","Hiragino Sans GB","Microsoft YaHei","Noto Sans SC",system-ui,-apple-system,sans-serif;
  --font-mono:"JetBrains Mono",ui-monospace,SFMono-Regular,Menlo,Consolas,"Courier New",monospace;
  --shell-w:1240px;
  --gutter:20px;
  --shadow:0 26px 64px rgba(0,0,0,.6);
  --ease:cubic-bezier(.2,.7,.2,1);
}
body[data-accent="ice"]{--accent:#45D6FF;--accent-soft:rgba(69,214,255,.12);--accent-line:rgba(69,214,255,.45);--on-accent:#05070D}
body[data-accent="gold"]{--accent:#FFC24B;--accent-soft:rgba(255,194,75,.12);--accent-line:rgba(255,194,75,.45);--on-accent:#0B0904}
body[data-accent="rose"]{--accent:#FF3D7F;--accent-soft:rgba(255,61,127,.14);--accent-line:rgba(255,61,127,.5);--on-accent:#12040A}
body[data-accent="cyan"]{--accent:#7CF7E4;--accent-soft:rgba(124,247,228,.12);--accent-line:rgba(124,247,228,.45);--on-accent:#04100E}
body[data-accent="amber"]{--accent:#FF9A3C;--accent-soft:rgba(255,154,60,.14);--accent-line:rgba(255,154,60,.5);--on-accent:#140A02}

/* ---------- 3. 基础排版与画布 ---------- */
body{
  background-color:var(--bg);
  background-image:
    radial-gradient(1100px 560px at 76% -12%,rgba(69,214,255,.09),transparent 62%),
    linear-gradient(rgba(30,42,56,.42) 1px,transparent 1px),
    linear-gradient(90deg,rgba(30,42,56,.42) 1px,transparent 1px);
  background-size:auto,80px 80px,80px 80px;
  color:var(--text);
  font-family:var(--font-body);
  font-size:17px;
  line-height:1.75;
  letter-spacing:.01em;
  -webkit-font-smoothing:antialiased;
  overflow-x:hidden;
}
h1,h2,h3,h4,h5{font-family:var(--font-display);font-weight:800;line-height:1.05;letter-spacing:-.01em}
h1{font-size:clamp(34px,5.4vw,58px);letter-spacing:-.02em}
h2{font-size:clamp(25px,3.4vw,38px)}
h3{font-size:clamp(19px,2.2vw,25px)}
h4{font-size:18px;letter-spacing:.01em}
p{margin:0 0 1em}
a{color:inherit;text-decoration:none;transition:color .18s var(--ease),border-color .18s var(--ease)}
a:hover{color:var(--accent)}
strong{color:var(--text);font-weight:600}
code,kbd,samp,pre{font-family:var(--font-mono);font-size:.92em}
.mono{font-family:var(--font-mono);letter-spacing:.04em}
#main-content{display:block;scroll-margin-top:150px}
.skip-link{
  position:fixed;left:14px;top:-80px;z-index:120;
  padding:10px 18px;background:var(--cyan);color:#05070D;
  font-family:var(--font-display);font-weight:700;font-size:15px;letter-spacing:.06em;
  transition:top .18s var(--ease);
}
.skip-link:focus{top:14px;color:#05070D}
.visually-hidden{position:absolute!important;width:1px;height:1px;margin:-1px;padding:0;overflow:hidden;clip:rect(0 0 0 0);white-space:nowrap;border:0}

/* ---------- 4. 容器 ---------- */
.shell{width:100%;max-width:var(--shell-w);margin-inline:auto;padding-inline:var(--gutter)}

/* ---------- 5. 双层页头 ---------- */
.site-header{position:sticky;top:0;z-index:60;background:var(--bg);border-bottom:1px solid var(--line)}
.header-rail{
  background:var(--panel);border-bottom:1px solid var(--line);
  max-height:72px;overflow:hidden;
  transition:max-height .28s var(--ease),opacity .2s var(--ease),border-color .2s var(--ease);
}
.header-rail__inner{display:flex;align-items:center;justify-content:space-between;gap:24px;padding-block:10px}
.header-rail__brand{
  margin:0;font-size:13px;line-height:1.6;color:var(--muted);
  white-space:nowrap;overflow:hidden;text-overflow:ellipsis;min-width:0;
}
.header-rail__status{
  display:flex;flex-wrap:wrap;align-items:center;gap:6px 18px;
  font-family:var(--font-mono);font-size:11px;letter-spacing:.14em;text-transform:uppercase;color:var(--muted);
}
.header-rail__status li{display:flex;align-items:center;gap:7px;white-space:nowrap}
.header-rail__status li::before{content:"";width:5px;height:5px;background:var(--accent);box-shadow:0 0 10px var(--accent)}
.site-header.is-condensed .header-rail{max-height:0;opacity:0;border-color:transparent}

.header-main{position:relative;background:linear-gradient(180deg,rgba(13,18,25,.94),rgba(5,7,13,.94))}
.header-main__inner{display:flex;align-items:center;gap:22px;padding-block:12px}

.brand{display:flex;align-items:center;gap:12px;flex:0 0 auto;color:var(--text)}
.brand:hover{color:var(--text)}
.brand__mark{position:relative;display:block;flex:0 0 auto;width:26px;height:26px;border:1px solid var(--line-strong);background:var(--panel-2)}
.brand__mark::before{content:"";position:absolute;inset:6px;background:var(--accent);box-shadow:0 0 14px var(--accent)}
.brand__mark::after{content:"";position:absolute;inset:0;background:linear-gradient(135deg,transparent 46%,var(--line-strong) 46%,var(--line-strong) 54%,transparent 54%)}
.brand__text{display:flex;flex-direction:column;line-height:1.16}
.brand__name{font-family:var(--font-display);font-weight:800;font-size:21px;letter-spacing:.01em;color:var(--text)}
.brand__sub{font-family:var(--font-mono);font-size:9.5px;letter-spacing:.2em;text-transform:uppercase;color:var(--muted)}

.nav-toggle{display:none;align-items:center;gap:9px;margin-left:auto;padding:10px 13px;border:1px solid var(--line);background:transparent;color:var(--text);font-family:var(--font-display);font-weight:700;font-size:14px;letter-spacing:.08em;transition:border-color .18s var(--ease),color .18s var(--ease)}
.nav-toggle:hover{border-color:var(--accent);color:var(--accent)}
.nav-toggle__bars{position:relative;display:block;width:18px;height:12px}
.nav-toggle__bars::before,.nav-toggle__bars::after{content:"";position:absolute;left:0;right:0;height:1.5px;background:currentColor;transition:transform .2s var(--ease)}
.nav-toggle__bars::before{top:0}
.nav-toggle__bars::after{bottom:0}
.site-header[data-open] .nav-toggle__bars::before{transform:translateY(5px) rotate(45deg)}
.site-header[data-open] .nav-toggle__bars::after{transform:translateY(-5px) rotate(-45deg)}
.nav-toggle__label{line-height:1}

.header-panel{display:flex;align-items:center;justify-content:space-between;gap:20px;flex:1 1 auto;min-width:0}
.primary-nav{min-width:0}
.primary-nav__list{display:flex;flex-wrap:wrap;align-items:center;gap:2px}
.primary-nav__item{list-style:none}
.primary-nav__link{
  position:relative;display:block;padding:9px 12px;
  font-family:var(--font-display);font-weight:700;font-size:15.5px;letter-spacing:.05em;
  color:var(--muted);border-bottom:2px solid transparent;
  transition:color .18s var(--ease),background .18s var(--ease),border-color .18s var(--ease);
}
.primary-nav__link:hover{color:var(--text);background:rgba(30,42,56,.55)}
.primary-nav__link[aria-current="page"]{color:var(--accent);border-bottom-color:var(--accent);background:var(--accent-soft)}
.header-actions{display:flex;align-items:center;gap:10px;flex:0 0 auto}

.scroll-progress{position:absolute;left:0;right:0;bottom:0;height:2px;overflow:hidden;pointer-events:none}
.scroll-progress__bar{display:block;width:0;height:100%;background:var(--accent);box-shadow:0 0 12px var(--accent);transition:width .1s linear}

/* ---------- 6. 按钮与链接 ---------- */
.btn{
  display:inline-flex;align-items:center;justify-content:center;gap:8px;
  padding:11px 17px;border:1px solid var(--line);background:var(--panel);color:var(--text);
  font-family:var(--font-display);font-weight:700;font-size:15px;letter-spacing:.05em;line-height:1;
  transition:background .18s var(--ease),border-color .18s var(--ease),color .18s var(--ease);
}
.btn:hover{border-color:var(--accent);color:var(--accent);background:var(--panel-2)}
.btn--accent{background:var(--accent);border-color:var(--accent);color:var(--on-accent)}
.btn--accent:hover{background:transparent;border-color:var(--accent);color:var(--accent)}
.btn--ghost{background:transparent;color:var(--muted)}
.btn--ghost:hover{color:var(--accent)}
.btn--sm{padding:8px 13px;font-size:13.5px}
.btn--copy{font-family:var(--font-mono);font-size:12px;letter-spacing:.08em;font-weight:500}
.btn.is-copied,.btn--copy.is-copied{border-color:var(--cyan);color:var(--cyan);background:transparent;box-shadow:inset 0 0 0 1px var(--cyan)}
.link-arrow{display:inline-flex;align-items:center;gap:9px;font-family:var(--font-display);font-weight:700;font-size:15px;letter-spacing:.04em;color:var(--text)}
.link-arrow::after{content:"→";color:var(--accent);transition:transform .18s var(--ease)}
.link-arrow:hover{color:var(--accent)}
.link-arrow:hover::after{transform:translateX(4px)}

/* ---------- 7. 页脚 ---------- */
.site-footer{
  margin-top:0;background:var(--panel);border-top:1px solid var(--line);color:var(--muted);
  background-image:linear-gradient(180deg,rgba(17,26,36,.85),rgba(5,7,13,.9));
}
.footer-grid{display:grid;grid-template-columns:1.5fr 1fr 1fr 1.4fr;gap:34px;padding:58px 0 42px}
.footer-col{min-width:0}
.footer-brand{margin:0 0 10px;font-family:var(--font-display);font-weight:800;font-size:23px;letter-spacing:.02em;color:var(--text)}
.footer-note{margin:0 0 14px;max-width:36ch;font-size:14px;line-height:1.75;color:var(--muted)}
.footer-icp{margin:0;font-family:var(--font-mono);font-size:12px;letter-spacing:.08em;color:var(--muted)}
.footer-col__title{
  margin:0 0 14px;padding-bottom:10px;border-bottom:1px solid var(--line);
  font-family:var(--font-mono);font-weight:500;font-size:11px;letter-spacing:.2em;text-transform:uppercase;color:var(--text);
}
.footer-links{display:flex;flex-direction:column;gap:10px}
.footer-links a{font-size:14.5px;color:var(--muted);border-bottom:1px solid transparent;width:fit-content}
.footer-links a:hover{color:var(--accent);border-bottom-color:var(--accent)}
.footer-contact{display:flex;flex-direction:column;gap:9px;margin:0 0 14px;font-family:var(--font-mono);font-size:13.5px;letter-spacing:.01em}
.footer-contact li{display:flex;gap:10px;align-items:baseline;color:var(--text);word-break:break-word}
.footer-contact__k{flex:0 0 auto;font-size:11px;letter-spacing:.14em;color:var(--muted)}
.footer-contact__v{min-width:0}
.footer-hours{margin:0;font-size:13px;line-height:1.75;color:var(--muted)}
.footer-base{
  display:flex;flex-wrap:wrap;align-items:center;justify-content:space-between;gap:8px 20px;
  padding:18px 0 28px;border-top:1px solid var(--line);
  font-family:var(--font-mono);font-size:12px;letter-spacing:.08em;color:var(--muted);
}
.footer-base p{margin:0}

/* ---------- 8. 章节与文本版式 ---------- */
.page-section{padding:clamp(40px,6vw,78px) 0;border-bottom:1px solid var(--line)}
.page-section:last-child{border-bottom:0}
.section-head{display:flex;flex-wrap:wrap;align-items:flex-end;justify-content:space-between;gap:16px;margin-bottom:26px}
.eyebrow{display:inline-flex;align-items:center;gap:9px;margin:0 0 10px;font-family:var(--font-mono);font-size:11px;letter-spacing:.22em;text-transform:uppercase;color:var(--accent)}
.eyebrow::before{content:"";width:22px;height:1px;background:var(--accent)}
.section-title{margin:0}
.section-note{margin:0;max-width:48ch;font-size:14px;color:var(--muted)}
.lede{max-width:62ch;font-size:18px;color:var(--muted)}
.rule{height:1px;border:0;background:var(--line)}
.prose{max-width:68ch}
.prose h2{margin:40px 0 12px}
.prose h3{margin:28px 0 10px}
.prose h2:first-child,.prose h3:first-child{margin-top:0}
.prose p{margin:0 0 1.1em}
.prose ul,.prose ol{margin:0 0 1.1em;padding-left:1.3em}
.prose li{margin-bottom:.45em}
.prose a{color:var(--accent);text-decoration:underline;text-underline-offset:3px}

/* ---------- 9. 网格与面板 ---------- */
.grid{display:grid;gap:20px}
.grid--2{grid-template-columns:repeat(2,minmax(0,1fr))}
.grid--3{grid-template-columns:repeat(3,minmax(0,1fr))}
.grid--aside{grid-template-columns:240px minmax(0,1fr);gap:28px}

.panel{background:var(--panel);border:1px solid var(--line)}
.panel--alt{background:var(--panel-2)}
.panel__head{display:flex;align-items:center;justify-content:space-between;gap:14px;padding:15px 20px;border-bottom:1px solid var(--line)}
.panel__title{margin:0;font-size:19px;letter-spacing:.02em}
.panel__index{font-family:var(--font-mono);font-size:11px;letter-spacing:.16em;color:var(--muted)}
.panel__body{padding:20px}
.panel-stack{display:flex;flex-direction:column}
.panel-stack>.panel+.panel{border-top:0}

.card{display:flex;flex-direction:column;gap:10px;padding:22px;background:var(--panel);border:1px solid var(--line);transition:border-color .18s var(--ease),background .18s var(--ease)}
.card:hover{border-color:var(--line-strong);background:var(--panel-2)}
.card__kicker{font-family:var(--font-mono);font-size:11px;letter-spacing:.18em;text-transform:uppercase;color:var(--accent)}
.card__title{margin:0;font-size:20px}
.card__text{margin:0;font-size:14.5px;color:var(--muted)}
.card__foot{display:flex;align-items:center;justify-content:space-between;gap:12px;margin-top:auto;padding-top:13px;border-top:1px solid var(--line)}

.list-plain{display:flex;flex-direction:column}
.list-plain li{display:flex;gap:10px;padding:11px 0;border-bottom:1px solid var(--line);font-size:15px;color:var(--muted)}
.list-plain li:last-child{border-bottom:0}

.tag{display:inline-flex;align-items:center;gap:6px;padding:4px 9px;border:1px solid var(--line-strong);font-family:var(--font-mono);font-size:11px;letter-spacing:.1em;text-transform:uppercase;color:var(--muted)}
.tag--accent{border-color:var(--accent);background:var(--accent-soft);color:var(--accent)}
.meta-line{font-family:var(--font-mono);font-size:11.5px;letter-spacing:.1em;color:var(--muted)}

.cta-band{display:flex;flex-wrap:wrap;align-items:center;justify-content:space-between;gap:20px;padding:26px;border:1px solid var(--line);background:linear-gradient(90deg,var(--panel-2),var(--panel))}
.cta-band__text{margin:0;font-family:var(--font-display);font-weight:800;font-size:20px;letter-spacing:.02em}
.cta-band__actions{display:flex;flex-wrap:wrap;gap:10px}

/* ---------- 10. 面包屑 ---------- */
.breadcrumbs{padding:14px 0;border-bottom:1px solid var(--line)}
.breadcrumbs__list{display:flex;flex-wrap:wrap;gap:8px;font-family:var(--font-mono);font-size:11.5px;letter-spacing:.1em;color:var(--muted)}
.breadcrumbs__item{display:flex;align-items:center;gap:8px}
.breadcrumbs__item::after{content:"/";color:var(--line-strong)}
.breadcrumbs__item:last-child::after{content:""}
.breadcrumbs__link{color:var(--muted)}
.breadcrumbs__link:hover{color:var(--accent)}
.breadcrumbs__item[aria-current="page"] .breadcrumbs__link{color:var(--text)}

/* ---------- 11. 状态摘要 ---------- */
.status-strip{display:grid;grid-template-columns:repeat(auto-fit,minmax(180px,1fr));border:1px solid var(--line);background:var(--panel)}
.status-card{display:flex;flex-direction:column;gap:4px;padding:16px 18px;border-right:1px solid var(--line);background:var(--panel)}
.status-card:last-child{border-right:0}
.status-card--live{box-shadow:inset 0 2px 0 var(--accent);background:var(--panel-2)}
.status-card__value{font-family:var(--font-mono);font-size:22px;line-height:1.3;color:var(--text)}
.status-card__label{font-size:12.5px;color:var(--muted)}
.status-card__hint{font-family:var(--font-mono);font-size:11px;letter-spacing:.12em;color:var(--accent)}

/* ---------- 12. 筛选 ---------- */
.filter-bar{display:flex;flex-wrap:wrap;align-items:center;gap:8px;padding:14px 0;margin-bottom:24px;border-top:1px solid var(--line);border-bottom:1px solid var(--line)}
.filter-btn{
  padding:8px 14px;border:1px solid var(--line);background:transparent;color:var(--muted);
  font-family:var(--font-mono);font-size:12px;letter-spacing:.1em;
  transition:background .16s var(--ease),border-color .16s var(--ease),color .16s var(--ease);
}
.filter-btn:hover{border-color:var(--accent);color:var(--accent)}
.filter-btn[aria-pressed="true"]{background:var(--accent);border-color:var(--accent);color:var(--on-accent)}
.filter-count{margin-left:auto;font-family:var(--font-mono);font-size:11.5px;letter-spacing:.1em;color:var(--muted)}
.is-hidden{display:none!important}
@keyframes itemIn{from{opacity:0;transform:translateY(6px)}to{opacity:1;transform:none}}
.filter-item.is-in{animation:itemIn .12s var(--ease) both}

/* ---------- 13. 自查清单 ---------- */
.checklist{border:1px solid var(--line);background:var(--panel)}
.checklist__item{
  display:grid;grid-template-columns:auto minmax(0,1fr);gap:6px 14px;align-items:start;
  padding:14px 18px;border-bottom:1px solid var(--line);
  transition:background .18s var(--ease),box-shadow .18s var(--ease);
}
.checklist__item:last-child{border-bottom:0}
.checklist__item:hover{background:var(--panel-2)}
.checklist__item.is-done{background:var(--accent-soft);box-shadow:inset 2px 0 0 var(--cyan)}
.checklist__index{padding-top:4px;font-family:var(--font-mono);font-size:12px;letter-spacing:.12em;color:var(--muted)}
.checklist__item.is-done .checklist__index{color:var(--cyan)}
.checklist__label{display:flex;gap:12px;align-items:flex-start;cursor:pointer;font-size:15.5px}
.checklist__input{
  position:relative;flex:0 0 auto;width:18px;height:18px;margin:4px 0 0;
  appearance:none;-webkit-appearance:none;border:1px solid var(--line-strong);background:var(--bg);
}
.checklist__input:checked{border-color:var(--cyan);background:var(--cyan)}
.checklist__input:checked::after{content:"";position:absolute;left:5px;top:1px;width:6px;height:11px;border:solid #05070D;border-width:0 2px 2px 0;transform:rotate(45deg)}
.checklist__text{color:var(--text)}
.checklist__desc{grid-column:2;margin:0;font-size:13.5px;line-height:1.7;color:var(--muted)}
.checklist__progress{display:flex;align-items:center;gap:14px;padding:14px 18px;border-top:1px solid var(--line);background:var(--panel-2)}
.checklist__track{position:relative;flex:1 1 auto;height:6px;background:var(--bg);border:1px solid var(--line);overflow:hidden}
.checklist__bar{display:block;width:0;height:100%;background:var(--cyan);transition:width .24s var(--ease)}
.checklist__count{font-family:var(--font-mono);font-size:12px;letter-spacing:.1em;color:var(--muted)}

/* ---------- 14. 时间轴 ---------- */
.timeline{position:relative}
.timeline__item{position:relative;padding-top:34px}
.timeline::before{content:"";position:absolute;left:0;right:0;top:7px;height:1px;background:var(--line)}
.timeline__node{position:absolute;top:1px;left:0;width:13px;height:13px;background:var(--bg);border:1px solid var(--accent)}
.timeline__node::after{content:"";position:absolute;inset:3px;background:var(--accent);opacity:0;transition:opacity .22s var(--ease)}
.timeline__item.is-lit .timeline__node::after{opacity:1}
.timeline__week{font-family:var(--font-mono);font-size:12px;letter-spacing:.12em;color:var(--accent)}
.timeline__body{margin-top:8px}

/* ---------- 15. 折叠列表 ---------- */
.fold{border:1px solid var(--line);background:var(--panel)}
.fold+.fold{border-top:0}
.fold__head{
  display:flex;width:100%;align-items:center;justify-content:space-between;gap:16px;
  padding:16px 18px;background:transparent;color:var(--text);text-align:left;
  font-family:var(--font-display);font-weight:700;font-size:17px;letter-spacing:.03em;
  transition:background .18s var(--ease),color .18s var(--ease);
}
.fold__head:hover{background:var(--panel-2);color:var(--accent)}
.fold__head[aria-expanded="true"]{background:var(--panel-2);color:var(--accent)}
.fold__icon{position:relative;flex:0 0 auto;width:14px;height:14px}
.fold__icon::before,.fold__icon::after{content:"";position:absolute;background:currentColor;transition:transform .2s var(--ease),opacity .2s var(--ease)}
.fold__icon::before{left:0;right:0;top:6px;height:1.5px}
.fold__icon::after{top:0;bottom:0;left:6px;width:1.5px}
.fold__head[aria-expanded="true"] .fold__icon::after{transform:scaleY(0);opacity:0}
.fold__body{padding:0 18px 18px;font-size:15px;color:var(--muted)}
.fold__body[hidden]{display:none}

/* ---------- 16. 图片容器基础规则（页面阶段放置占位） ---------- */
.media{display:block;width:100%;background:var(--panel-2);border:1px solid var(--line)}
.media__frame{
  position:relative;display:block;width:100%;aspect-ratio:16/9;overflow:hidden;
  background-image:
    linear-gradient(135deg,rgba(69,214,255,.12),transparent 62%),
    repeating-linear-gradient(90deg,rgba(30,42,56,.9) 0 1px,transparent 1px 30px),
    repeating-linear-gradient(0deg,rgba(30,42,56,.6) 0 1px,transparent 1px 30px);
  background-color:var(--panel-2);
}
.media__img{position:absolute;inset:0;width:100%;height:100%;object-fit:cover}
.media__caption{padding:10px 14px;border-top:1px solid var(--line);background:var(--panel);font-family:var(--font-mono);font-size:11.5px;letter-spacing:.08em;color:var(--muted)}
.media--wide .media__frame{aspect-ratio:21/9}
.media--square .media__frame{aspect-ratio:1/1}
.media--tall .media__frame{aspect-ratio:3/4}

/* ---------- 17. 回顶与显现动效 ---------- */
.to-top{
  position:fixed;right:20px;bottom:24px;z-index:70;
  display:inline-flex;align-items:center;gap:8px;padding:10px 14px;
  background:var(--panel);border:1px solid var(--line);color:var(--muted);
  font-family:var(--font-mono);font-size:11.5px;letter-spacing:.12em;
  opacity:0;visibility:hidden;
  transition:opacity .2s var(--ease),visibility .2s var(--ease),border-color .2s var(--ease),color .2s var(--ease);
}
.to-top.is-visible{opacity:1;visibility:visible}
.to-top:hover{border-color:var(--accent);color:var(--accent)}

.js-reveal [data-reveal]{opacity:0;transform:translateY(12px);transition:opacity .45s var(--ease),transform .45s var(--ease)}
.js-reveal [data-reveal].is-visible{opacity:1;transform:none}

/* ---------- 18. 响应式 ---------- */
@media (max-width:1100px){
  .nav-toggle{display:inline-flex}
  .header-panel{
    position:absolute;top:100%;left:0;right:0;z-index:65;
    display:none;flex-direction:column;align-items:stretch;justify-content:flex-start;gap:0;
    padding:10px 0 16px;background:var(--panel);border-bottom:1px solid var(--line);box-shadow:var(--shadow);
    max-height:calc(100vh - 140px);overflow-y:auto;
  }
  .site-header[data-open] .header-panel{display:flex;animation:itemIn .16s var(--ease) both}
  .primary-nav__list{flex-direction:column;align-items:stretch;gap:0;padding-inline:var(--gutter)}
  .primary-nav__link{padding:14px 10px;font-size:17px;border-bottom:1px solid var(--line);border-left:2px solid transparent}
  .primary-nav__link[aria-current="page"]{border-bottom-color:var(--line);border-left-color:var(--accent);padding-left:14px}
  .header-actions{flex-direction:column;align-items:stretch;gap:9px;padding:16px var(--gutter) 4px}
}
@media (max-width:980px){
  :root{--gutter:18px}
  .header-rail{max-height:150px}
  .header-rail__inner{flex-direction:column;align-items:flex-start;gap:7px;padding-block:11px}
  .header-rail__brand{white-space:normal;font-size:12px;line-height:1.55}
  .grid--2,.grid--3,.grid--aside{grid-template-columns:1fr;gap:18px}
  .footer-grid{grid-template-columns:1fr 1fr;gap:28px;padding:44px 0 30px}
  .footer-col--brand{grid-column:1/-1}
}
@media (max-width:640px){
  :root{--gutter:15px}
  body{font-size:16px}
  .brand__name{font-size:19px}
  .brand__sub{display:none}
  .footer-grid{grid-template-columns:1fr;gap:24px;padding:36px 0 24px}
  .footer-base{flex-direction:column;align-items:flex-start;gap:6px}
  .status-strip{grid-template-columns:1fr}
  .status-card{border-right:0;border-bottom:1px solid var(--line)}
  .status-card:last-child{border-bottom:0}
  .cta-band{padding:20px}
  .to-top{right:12px;bottom:14px}
}

/* ---------- 19. 降低动效偏好 ---------- */
@media (prefers-reduced-motion:reduce){
  *,*::before,*::after{
    animation-duration:.001ms!important;
    animation-iteration-count:1!important;
    transition-duration:.001ms!important;
    scroll-behavior:auto!important;
  }
  .js-reveal [data-reveal]{opacity:1;transform:none}
  .timeline__node::after{opacity:1}
}
@media (prefers-reduced-motion:no-preference){
  html{scroll-behavior:smooth}
}