/* ==========================================================================
   万豪斗地主牌局 · /assets/site.css
   共享外壳：reset / 变量 / 中文排版 / 边框式页头 / 目录式页脚 / 通用组件
   ========================================================================== */

*,*::before,*::after{box-sizing:border-box;}

:root{
  /* 牌桌材质色阶 */
  --emerald-950:#08221C;
  --emerald-900:#0F3D33;
  --emerald-700:#17594A;
  --emerald-500:#2C7A66;
  --gold:#C9A227;
  --gold-soft:#E7CE7A;
  --gold-deep:#A8841B;
  --red:#B32E2E;
  --cream:#F5EFE2;
  --cream-2:#E8DFC9;
  --paper:#FFFDF7;
  --ink:#1E1B18;
  --ink-soft:#3A3630;
  --muted:#6B7A72;
  --line-gold:rgba(201,162,39,.42);
  --line-soft:rgba(30,27,24,.14);
  --glass:rgba(8,34,28,.76);
  --glass-light:rgba(245,239,226,.62);

  /* 字体 */
  --font-display:"Songti SC","STSong","SimSun","Source Han Serif SC","Noto Serif SC",Georgia,"Times New Roman",serif;
  --font-body:"PingFang SC","Hiragino Sans GB","Microsoft YaHei","Source Han Sans SC","Noto Sans SC",system-ui,-apple-system,"Segoe UI",sans-serif;
  --font-mono:ui-monospace,SFMono-Regular,Menlo,Consolas,"Courier New",monospace;

  /* 尺度 */
  --rail-w:0px;
  --beam-min:64px;
  --wrap:1260px;
  --read:860px;
  --radius:2px;
  --shadow-card:0 10px 30px rgba(8,34,28,.10);
  --ease:cubic-bezier(.22,.61,.36,1);
  --t-fast:180ms;
  --t-mid:240ms;
}

@media (min-width:900px){ :root{ --rail-w:40px; } }
@media (min-width:1200px){ :root{ --rail-w:56px; } }

html{
  -webkit-text-size-adjust:100%;
  scroll-behavior:smooth;
}

body{
  margin:0;
  min-height:100vh;
  padding-inline:var(--rail-w);
  background:
    radial-gradient(1100px 560px at 10% -12%, rgba(201,162,39,.12), transparent 62%),
    radial-gradient(900px 500px at 100% 8%, rgba(15,61,51,.06), transparent 60%),
    var(--cream);
  color:var(--ink);
  font-family:var(--font-body);
  font-size:17px;
  font-weight:400;
  line-height:1.85;
  letter-spacing:.01em;
  overflow-x:hidden;
}

h1,h2,h3,h4,h5{
  margin:0 0 .6em;
  font-family:var(--font-display);
  font-weight:800;
  line-height:1.16;
  letter-spacing:.02em;
  color:var(--emerald-900);
}

p{margin:0 0 1.1em;}
a{color:var(--emerald-700);text-underline-offset:3px;}
img{max-width:100%;height:auto;}
ul,ol{margin:0;padding:0;}
strong{font-weight:600;color:var(--emerald-900);}
hr{border:0;}

:focus-visible{outline:3px solid var(--gold);outline-offset:2px;border-radius:1px;}

.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;
}

/* ---------- 跳转链接 ---------- */
.skip-link{
  position:fixed;left:12px;top:-140px;z-index:200;
  display:inline-block;
  padding:10px 20px;
  background:var(--gold);color:var(--emerald-950);
  font-weight:700;font-size:14px;letter-spacing:.08em;
  text-decoration:none;
  border:1px solid var(--emerald-950);border-radius:var(--radius);
  transition:top var(--t-fast) var(--ease);
}
.skip-link:focus{top:12px;}

/* ==========================================================================
   页头：框架式导航（左右金线竖框 + 顶部横梁 + 可折叠牌局标签）
   ========================================================================== */

.site-header{
  position:sticky;
  top:0;
  z-index:80;
}

/* 边框条 */
.frame-rail{
  display:none;
  position:fixed;
  top:0;bottom:0;width:var(--rail-w);
  background:linear-gradient(180deg,var(--emerald-950) 0%,var(--emerald-900) 42%,var(--emerald-950) 100%);
  border-inline:1px solid var(--line-gold);
  z-index:90;
  align-items:center;justify-content:center;
  overflow:hidden;
}
.frame-rail--left{left:0;}
.frame-rail--right{right:0;}

@media (min-width:900px){ .frame-rail{display:flex;} }

.rail-note{
  writing-mode:vertical-rl;
  font-family:var(--font-mono);
  font-size:11px;
  letter-spacing:.36em;
  text-transform:uppercase;
  color:rgba(231,206,122,.72);
  white-space:nowrap;
}
.frame-rail--right .rail-note{transform:rotate(180deg);}

.rail-chips{
  position:absolute;left:50%;bottom:26px;transform:translateX(-50%);
  display:grid;gap:4px;justify-items:center;
}
.rail-chips i{display:block;height:3px;border-radius:2px;background:var(--gold);opacity:.55;}
.rail-chips i:nth-child(1){width:16px;}
.rail-chips i:nth-child(2){width:12px;}
.rail-chips i:nth-child(3){width:8px;}

/* 横梁 */
.site-header__beam{
  position:relative;
  z-index:2;
  background:linear-gradient(180deg,#123F35 0%,var(--emerald-900) 100%);
  border-bottom:1px solid var(--line-gold);
  box-shadow:0 6px 26px rgba(8,34,28,.30);
}

.beam__inner{
  max-width:var(--wrap);
  margin:0 auto;
  min-height:var(--beam-min);
  display:flex;
  align-items:center;
  flex-wrap:nowrap;
  gap:14px;
  padding:10px clamp(16px,3vw,36px);
}

.brand{
  display:inline-flex;align-items:center;gap:12px;
  margin-right:auto;
  text-decoration:none;color:var(--cream);
  min-width:0;
}
.brand__mark{
  flex:none;
  width:38px;height:38px;
  display:grid;place-items:center;
  font-family:var(--font-display);font-size:20px;font-weight:800;
  color:var(--emerald-950);
  background:linear-gradient(140deg,var(--gold-soft),var(--gold));
  border:1px solid rgba(231,206,122,.75);
  border-radius:50%;
  box-shadow:inset 0 0 0 3px rgba(8,34,28,.34),0 2px 8px rgba(0,0,0,.35);
  transform:rotate(-6deg);
  transition:transform var(--t-mid) var(--ease);
}
.brand:hover .brand__mark{transform:rotate(0deg) scale(1.05);}
.brand__text{display:flex;flex-direction:column;line-height:1.25;min-width:0;}
.brand__line{
  font-family:var(--font-display);font-weight:800;
  font-size:clamp(15px,1.6vw,19px);letter-spacing:.04em;
  white-space:nowrap;
}
.brand__sub{
  font-size:11px;letter-spacing:.24em;text-transform:uppercase;
  color:var(--gold-soft);white-space:nowrap;
}

.version-badge{
  display:inline-flex;align-items:center;gap:8px;
  padding:6px 13px;
  font-family:var(--font-mono);font-size:12px;letter-spacing:.08em;
  color:var(--gold-soft);
  background:rgba(231,206,122,.08);
  border:1px solid var(--line-gold);
  border-radius:999px;
  white-space:nowrap;
}
.version-badge::before{
  content:"";width:6px;height:6px;border-radius:50%;
  background:var(--red);box-shadow:0 0 0 3px rgba(179,46,46,.22);
}

.nav-toggle{
  display:inline-flex;align-items:center;gap:10px;
  padding:9px 15px;
  background:transparent;color:var(--cream);
  border:1px solid var(--line-gold);border-radius:var(--radius);
  font-family:var(--font-body);font-size:13px;font-weight:600;letter-spacing:.18em;
  cursor:pointer;
  transition:background var(--t-fast) var(--ease),color var(--t-fast) var(--ease),border-color var(--t-fast) var(--ease);
}
.nav-toggle:hover{background:rgba(201,162,39,.16);border-color:var(--gold-soft);}
.nav-toggle:focus-visible{outline:3px solid var(--gold-soft);outline-offset:2px;}
.nav-toggle__bars{position:relative;display:inline-block;width:18px;height:12px;flex:none;}
.nav-toggle__bars::before,
.nav-toggle__bars::after{
  content:"";position:absolute;left:0;right:0;height:1.5px;background:currentColor;
  transition:transform var(--t-mid) var(--ease),opacity var(--t-fast) var(--ease);
}
.nav-toggle__bars::before{top:0;}
.nav-toggle__bars::after{bottom:0;}
.site-header[data-open] .nav-toggle,
.nav-toggle[aria-expanded="true"]{
  background:var(--gold);color:var(--emerald-950);border-color:var(--gold);
}
.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);}

/* 玻璃导航层 */
.site-nav{
  position:fixed;
  top:0;bottom:0;left:0;right:0;
  z-index:1;
  display:grid;
  grid-template-columns:minmax(0,1fr);
  gap:24px;
  padding:96px clamp(16px,5vw,28px) 44px;
  overflow-y:auto;
  background:var(--glass);
  -webkit-backdrop-filter:blur(16px) saturate(140%);
  backdrop-filter:blur(16px) saturate(140%);
  border-bottom:1px solid var(--line-gold);
  opacity:0;visibility:hidden;
  transform:translateY(-12px);
  transition:opacity var(--t-mid) var(--ease),transform var(--t-mid) var(--ease),visibility var(--t-mid);
}
.site-header[data-open] .site-nav{
  opacity:1;visibility:visible;transform:translateY(0);
}

.nav-list{
  list-style:none;
  display:grid;
  grid-template-columns:minmax(0,1fr);
  gap:1px;
  background:var(--line-gold);
  border:1px solid var(--line-gold);
}
.nav-list > li{background:rgba(8,34,28,.58);}

.nav-link{
  position:relative;
  display:flex;flex-direction:column;gap:6px;height:100%;
  padding:16px 18px;
  color:var(--cream);text-decoration:none;
  transition:background var(--t-fast) var(--ease),color var(--t-fast) var(--ease),padding-left var(--t-fast) var(--ease);
}
.nav-link::before{
  content:"";position:absolute;left:0;top:0;bottom:0;width:0;
  background:var(--gold);
  transition:width var(--t-mid) var(--ease);
}
.nav-link:hover{background:rgba(44,122,102,.36);padding-left:24px;}
.nav-link:hover::before{width:3px;}
.nav-link:focus-visible{outline:3px solid var(--gold-soft);outline-offset:-3px;}
.nav-num{font-family:var(--font-mono);font-size:11px;letter-spacing:.22em;color:var(--gold);}
.nav-name{font-family:var(--font-display);font-size:18px;font-weight:800;letter-spacing:.06em;}
.nav-note{font-size:12px;line-height:1.55;color:rgba(245,239,226,.62);letter-spacing:.02em;}
.nav-link[aria-current="page"]{background:var(--gold);color:var(--emerald-950);}
.nav-link[aria-current="page"]::before{width:3px;background:var(--red);}
.nav-link[aria-current="page"] .nav-num{color:var(--red);}
.nav-link[aria-current="page"] .nav-name{color:var(--emerald-950);}
.nav-link[aria-current="page"] .nav-note{color:rgba(11,46,39,.76);}

.nav-aside{
  padding-top:20px;
  border-top:1px solid var(--line-gold);
}
.nav-aside__title{
  margin:0 0 14px;
  font-family:var(--font-mono);font-size:11px;letter-spacing:.26em;text-transform:uppercase;
  color:var(--gold);
}
.nav-aside__list{
  list-style:none;display:grid;gap:11px;
  font-size:13px;line-height:1.6;color:rgba(245,239,226,.82);
}
.nav-aside__list li{display:flex;gap:10px;align-items:baseline;}
.nav-aside__list strong{color:var(--gold-soft);font-family:var(--font-mono);letter-spacing:.06em;}
.chip-dot{
  flex:none;width:8px;height:8px;border-radius:50%;
  background:var(--gold);transform:translateY(-1px);
}
.chip-dot--red{background:var(--red);box-shadow:0 0 0 3px rgba(179,46,46,.20);}
.chip-dot--green{background:var(--emerald-500);}
.nav-aside__cta{margin-top:18px;width:100%;}

@media (min-width:620px){
  .nav-list{grid-template-columns:repeat(2,minmax(0,1fr));}
}
@media (min-width:900px){
  .site-nav{
    position:absolute;
    top:100%;left:0;right:0;bottom:auto;
    max-height:calc(100vh - 96px);
    padding:clamp(20px,2.6vw,32px) clamp(20px,4vw,44px) clamp(24px,3vw,36px);
    gap:clamp(20px,3vw,36px);
    transform:translateY(-10px);
  }
  .nav-list{grid-template-columns:repeat(3,minmax(0,1fr));}
  .nav-aside{border-top:0;border-left:1px solid var(--line-gold);padding-top:0;padding-left:clamp(16px,2vw,26px);}
}
@media (min-width:1140px){
  .site-nav{grid-template-columns:minmax(0,1fr) 280px;}
  .nav-aside__cta{display:none;}
}

/* 滚动进度（由 JS 注入） */
.scroll-progress{
  position:absolute;left:0;bottom:-1px;z-index:3;
  width:100%;height:2px;
  transform:scaleX(0);transform-origin:0 50%;
  background:linear-gradient(90deg,var(--gold) 0%,var(--gold-soft) 62%,var(--red) 100%);
  transition:transform 90ms linear;
}

/* ==========================================================================
   页脚：奶油底目录 + 深翡翠收尾
   ========================================================================== */

.site-footer{
  position:relative;
  background:linear-gradient(180deg,var(--cream) 0%,#F1E9D8 100%);
  border-top:1px solid var(--line-gold);
  color:var(--ink);
}
.site-footer::before{
  content:"";position:absolute;top:-1px;left:0;height:3px;width:min(420px,54vw);
  background:linear-gradient(90deg,var(--gold),rgba(201,162,39,0));
}

.footer__inner{
  max-width:var(--wrap);
  margin:0 auto;
  padding:clamp(38px,5vw,66px) clamp(16px,4vw,44px) clamp(26px,3vw,38px);
}

.footer__grid{
  display:grid;
  grid-template-columns:minmax(0,1fr);
  gap:clamp(24px,3vw,40px);
}
@media (min-width:720px){ .footer__grid{grid-template-columns:repeat(2,minmax(0,1fr));} }
@media (min-width:1080px){ .footer__grid{grid-template-columns:1.2fr 1fr 1fr 1fr;} }

.footer__brand-line{
  margin:0 0 4px;
  font-family:var(--font-display);font-size:22px;font-weight:800;
  color:var(--emerald-900);letter-spacing:.04em;
}
.footer__brand-sub{
  margin:0 0 14px;
  font-family:var(--font-mono);font-size:11px;letter-spacing:.2em;text-transform:uppercase;
  color:var(--emerald-700);
}
.footer__note{
  font-size:13.5px;line-height:1.85;color:var(--ink-soft);
  max-width:36ch;margin:0 0 16px;
}
.footer__quick{display:flex;flex-wrap:wrap;gap:8px 20px;}

.index-col__title{
  margin:0 0 12px;padding-bottom:9px;
  font-family:var(--font-mono);font-size:11px;letter-spacing:.22em;text-transform:uppercase;
  color:var(--emerald-700);
  border-bottom:1px solid var(--line-soft);
}
.index-col__note{
  margin:14px 0 0;
  font-size:13px;line-height:1.8;color:var(--muted);
  max-width:30ch;
}

.index-list{list-style:none;display:grid;gap:8px;}
.index-list a{
  position:relative;display:inline-block;
  color:var(--ink);text-decoration:none;font-size:14.5px;
  padding-left:0;
  transition:color var(--t-fast) var(--ease),padding-left var(--t-fast) var(--ease);
}
.index-list a::before{
  content:"";position:absolute;left:0;top:50%;
  width:0;height:1px;background:var(--gold);
  transition:width var(--t-fast) var(--ease);
}
.index-list a:hover,
.index-list a:focus-visible{color:var(--emerald-700);padding-left:16px;}
.index-list a:hover::before,
.index-list a:focus-visible::before{width:10px;}

.footer__contact{
  margin-top:clamp(26px,3vw,40px);
  padding-top:20px;
  border-top:1px solid var(--line-soft);
  display:flex;flex-wrap:wrap;gap:8px 26px;
  font-size:13px;color:var(--ink-soft);
}
.contact-line{display:inline-flex;gap:8px;align-items:baseline;}
.contact-line strong{font-size:11px;letter-spacing:.18em;color:var(--emerald-700);font-family:var(--font-mono);font-weight:600;}

.footer__legal{
  margin-top:16px;
  display:flex;flex-wrap:wrap;gap:10px 24px;align-items:center;justify-content:space-between;
  font-size:13px;
}
.legal-links{list-style:none;display:flex;flex-wrap:wrap;gap:18px;}
.legal-links a{
  color:var(--emerald-700);text-decoration:none;
  border-bottom:1px solid transparent;
  transition:border-color var(--t-fast) var(--ease),color var(--t-fast) var(--ease);
}
.legal-links a:hover,.legal-links a:focus-visible{border-color:var(--gold);color:var(--emerald-900);}
.footer__record{
  font-family:var(--font-mono);font-size:12px;letter-spacing:.08em;color:var(--muted);
}

.footer__mark{
  background:linear-gradient(180deg,var(--emerald-900) 0%,var(--emerald-950) 100%);
  border-top:1px solid var(--line-gold);
  color:rgba(245,239,226,.74);
}
.footer__mark-inner{
  max-width:var(--wrap);margin:0 auto;
  padding:18px clamp(16px,4vw,44px);
  display:flex;flex-wrap:wrap;gap:10px 24px;align-items:center;justify-content:space-between;
  font-size:12px;letter-spacing:.1em;
}
.footer__mark-brand{
  font-family:var(--font-display);font-size:14px;font-weight:800;letter-spacing:.14em;
  color:var(--gold-soft);
}
.footer__mark-tags{display:flex;flex-wrap:wrap;gap:6px 20px;font-family:var(--font-mono);}

/* ==========================================================================
   通用排版与容器
   ========================================================================== */

.container{width:100%;max-width:var(--wrap);margin-inline:auto;padding-inline:clamp(16px,4vw,44px);}
.container--narrow{max-width:960px;}
.container--read{max-width:var(--read);}

.section{padding:clamp(44px,6vw,88px) 0;}
.section--tight{padding:clamp(28px,4vw,52px) 0;}
.section--cream2{background:var(--cream-2);}
.section--emerald{background:var(--emerald-900);color:rgba(245,239,226,.88);}
.section--emerald h2,.section--emerald h3{color:var(--gold-soft);}
.section--emerald .section__title{color:var(--gold-soft);}
.section--emerald .eyebrow{color:var(--gold-soft);}
.section--emerald .lede{color:rgba(245,239,226,.82);}
.section--band{
  background:linear-gradient(90deg,var(--emerald-700) 0%,var(--emerald-900) 100%);
  border-block:1px solid var(--line-gold);
  color:rgba(245,239,226,.88);
}
.section--band h2,.section--band h3{color:var(--gold-soft);}

.section__head{
  display:flex;flex-wrap:wrap;align-items:flex-end;justify-content:space-between;
  gap:16px;
  margin-bottom:clamp(20px,3vw,34px);
  padding-bottom:14px;
  border-bottom:1px solid var(--line-soft);
}
.section--emerald .section__head,
.section--band .section__head{border-bottom-color:var(--line-gold);}
.section__title{
  margin:0;
  font-family:var(--font-display);font-weight:800;
  font-size:clamp(1.5rem,2.6vw,2.2rem);
  color:var(--emerald-900);
}
.section--emerald .section__title,
.section--band .section__title{color:var(--gold-soft);}

.eyebrow{
  display:inline-flex;align-items:center;gap:10px;
  margin:0 0 14px;
  font-family:var(--font-mono);font-size:12px;letter-spacing:.26em;text-transform:uppercase;
  color:var(--emerald-700);
}
.eyebrow::before{content:"";display:block;width:28px;height:2px;background:var(--gold);}
.eyebrow--light{color:var(--gold-soft);}

.display-title{
  margin:0 0 .4em;
  font-family:var(--font-display);font-weight:800;
  font-size:clamp(2.2rem,5vw,4.4rem);
  line-height:1.08;letter-spacing:.02em;
  color:var(--emerald-900);
  text-shadow:0 2px 6px rgba(15,61,51,.14);
}
.display-title--gold{
  background:linear-gradient(180deg,var(--gold-soft) 0%,var(--gold) 70%,var(--gold-deep) 100%);
  -webkit-background-clip:text;background-clip:text;
  color:transparent;-webkit-text-fill-color:transparent;
  text-shadow:0 2px 6px rgba(0,0,0,.35);
}

.lede{
  max-width:60ch;
  font-size:clamp(1rem,1.4vw,1.15rem);
  line-height:1.9;
  color:var(--ink-soft);
}

.rule-gold{
  height:1px;border:0;margin:clamp(24px,3vw,40px) 0;
  background:linear-gradient(90deg,var(--gold),rgba(201,162,39,0));
}

.note-vertical{
  writing-mode:vertical-rl;
  font-family:var(--font-mono);font-size:13px;letter-spacing:.32em;text-transform:uppercase;
  color:var(--muted);
}

.glass{
  background:var(--glass-light);
  -webkit-backdrop-filter:blur(12px) saturate(130%);
  backdrop-filter:blur(12px) saturate(130%);
  border:1px solid var(--line-gold);
  border-radius:var(--radius);
}

/* 网格与卡片 */
.grid{display:grid;gap:clamp(16px,2.2vw,28px);}
.grid--2{grid-template-columns:repeat(auto-fit,minmax(260px,1fr));}
.grid--3{grid-template-columns:repeat(auto-fit,minmax(230px,1fr));}
.grid--4{grid-template-columns:repeat(auto-fit,minmax(190px,1fr));}

.card{
  position:relative;
  padding:clamp(18px,2.4vw,28px);
  background:var(--paper);
  border:1px solid var(--line-soft);
  border-radius:var(--radius);
  transition:transform var(--t-mid) var(--ease),border-color var(--t-mid) var(--ease),box-shadow var(--t-mid) var(--ease);
}
.card::before{
  content:"";position:absolute;left:0;top:0;height:3px;width:0;
  background:linear-gradient(90deg,var(--gold),var(--gold-soft));
  transition:width var(--t-mid) var(--ease);
}
.card:hover{transform:translateY(-4px);border-color:var(--line-gold);box-shadow:var(--shadow-card);}
.card:hover::before{width:64px;}
.card__title{
  margin:0 0 10px;
  font-family:var(--font-display);font-weight:800;
  font-size:clamp(1.1rem,1.6vw,1.35rem);
  color:var(--emerald-900);
}
.card__body{margin:0;font-size:15px;line-height:1.85;color:var(--ink-soft);}
.card__meta{
  margin-top:14px;
  font-family:var(--font-mono);font-size:12px;letter-spacing:.08em;color:var(--muted);
}
.card--glass{
  background:rgba(255,253,247,.58);
  -webkit-backdrop-filter:blur(10px);backdrop-filter:blur(10px);
  border-color:var(--line-gold);
}
.card--emerald{background:var(--emerald-900);color:rgba(245,239,226,.86);border-color:var(--line-gold);}
.card--emerald .card__title{color:var(--gold-soft);}
.card--emerald .card__body{color:rgba(245,239,226,.82);}
.card--emerald .card__meta{color:rgba(231,206,122,.72);}

/* 标签 */
.tag{
  display:inline-flex;align-items:center;gap:6px;
  padding:4px 11px;
  font-family:var(--font-mono);font-size:11px;letter-spacing:.16em;
  color:var(--emerald-700);
  background:rgba(201,162,39,.10);
  border:1px solid var(--line-gold);
  border-radius:999px;
}
.tag--red{color:var(--cream);background:var(--red);border-color:var(--red);}
.tag--gold{color:var(--emerald-950);background:var(--gold);border-color:var(--gold);}

/* 图像容器基础规则（页面阶段放入 <img>） */
.figure{display:block;margin:0;}
.figure__media{
  position:relative;overflow:hidden;
  aspect-ratio:4/3;
  background:var(--cream-2);
  border:1px solid var(--line-gold);
  border-radius:var(--radius);
}
.figure__media img{
  display:block;width:100%;height:100%;
  object-fit:cover;object-position:center;
  filter:saturate(.94) contrast(1.05) brightness(.96);
  transition:transform 320ms var(--ease);
}
.figure:hover .figure__media img{transform:scale(1.02);}
.figure__media--wide{aspect-ratio:16/9;}
.figure__media--square{aspect-ratio:1/1;}
.figure__media--portrait{aspect-ratio:3/4;}
.figure__media--tall{aspect-ratio:2/3;}
.figure__caption{
  margin-top:10px;padding-left:12px;
  border-left:1px solid var(--line-gold);
  font-size:13px;line-height:1.75;color:var(--muted);
}

/* 目录索引 */
.toc{
  padding:clamp(16px,2vw,24px);
  background:var(--paper);
  border:1px solid var(--line-gold);
  border-radius:var(--radius);
}
.toc__title{
  margin:0 0 14px;
  font-family:var(--font-mono);font-size:11px;letter-spacing:.24em;text-transform:uppercase;
  color:var(--emerald-700);
}
.toc__list{list-style:none;display:grid;gap:2px;}
.toc__link{
  display:flex;gap:12px;align-items:baseline;
  padding:8px 10px;
  font-size:15px;color:var(--ink);text-decoration:none;
  border-left:2px solid transparent;
  transition:background var(--t-fast) var(--ease),border-color var(--t-fast) var(--ease),color var(--t-fast) var(--ease),transform var(--t-fast) var(--ease);
}
.toc__link:hover{background:rgba(201,162,39,.12);border-left-color:var(--gold);transform:translateX(6px);}
.toc__link[aria-current="true"]{
  background:rgba(23,89,74,.10);
  border-left-color:var(--emerald-700);
  color:var(--emerald-900);font-weight:600;
}
.toc__link:focus-visible{outline:3px solid var(--gold);outline-offset:2px;}

/* 面包屑 */
.breadcrumb{margin:0 0 18px;}
.breadcrumb__list{
  list-style:none;display:flex;flex-wrap:wrap;gap:8px;
  font-family:var(--font-mono);font-size:13px;letter-spacing:.06em;color:var(--muted);
}
.breadcrumb__item + .breadcrumb__item::before{content:"/";margin-right:8px;color:var(--gold);}
.breadcrumb__item a{color:var(--emerald-700);text-decoration:none;}
.breadcrumb__item a:hover,.breadcrumb__item a:focus-visible{color:var(--gold);}

/* 手风琴 */
.accordion{border-top:1px solid var(--line-soft);}
.accordion__item{border-bottom:1px solid var(--line-soft);}
.accordion__trigger{
  width:100%;
  display:flex;align-items:center;justify-content:space-between;gap:16px;
  padding:18px 4px;
  background:none;border:0;cursor:pointer;text-align:left;
  font-family:var(--font-display);font-size:clamp(1rem,1.5vw,1.15rem);font-weight:800;letter-spacing:.02em;
  color:var(--emerald-900);
  transition:color var(--t-fast) var(--ease);
}
.accordion__trigger:hover{color:var(--gold);}
.accordion__trigger:focus-visible{outline:3px solid var(--gold);outline-offset:-3px;}
.accordion__icon{position:relative;flex:none;width:16px;height:16px;}
.accordion__icon::before,
.accordion__icon::after{
  content:"";position:absolute;background:var(--gold);
  transition:transform var(--t-mid) var(--ease),opacity var(--t-fast) var(--ease);
}
.accordion__icon::before{left:0;right:0;top:7px;height:1.5px;}
.accordion__icon::after{top:0;bottom:0;left:7px;width:1.5px;}
.accordion__trigger[aria-expanded="true"] .accordion__icon::after{transform:scaleY(0);}
.accordion__panel{
  padding:0 4px 20px;
  font-size:16px;line-height:1.85;color:var(--ink-soft);
}
.accordion__panel[hidden]{display:none;}

/* 显现 */
.js [data-reveal]{
  opacity:0;
  transform:translateY(8px);
  transition:opacity 420ms var(--ease),transform 420ms var(--ease);
}
.js [data-reveal].is-revealed{opacity:1;transform:none;}

/* ==========================================================================
   响应式与无障碍
   ========================================================================== */

@media (max-width:1080px){
  .version-badge{display:none;}
}
@media (max-width:760px){
  .beam__cta{display:none;}
  .footer__legal{justify-content:flex-start;}
}
@media (max-width:560px){
  body{font-size:16px;}
  .beam__inner{gap:10px;padding-inline:14px;}
  .brand__mark{width:34px;height:34px;font-size:18px;}
  .brand__line{font-size:14px;}
  .nav-toggle{font-size:12px;letter-spacing:.12em;padding:8px 12px;}
  .site-nav{padding:88px 16px 40px;}
}

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