/* ============================================================
   BB体育CN · 共享站点样式 /assets/site.css
   深靛蓝基底 · 荧光青数据点 · 暖橙行动点 · 奶油纸叙事面板
   ============================================================ */

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

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

:root{
  /* 色彩 */
  --ink:#0D1530;
  --ink-2:#18234C;
  --ink-3:#1D2A58;
  --line:#2E3A5E;
  --mist:#8E9BBB;
  --cream:#F1E9D8;
  --cyan:#25E8C9;
  --orange:#FF8A3D;
  --rust:#E0532F;
  --brown:#15100C;
  --paper:#E7ECF7;

  /* 字体 */
  --font-head:"Archivo Narrow","Oswald","Helvetica Neue",-apple-system,BlinkMacSystemFont,"PingFang SC","Hiragino Sans GB","Microsoft YaHei",sans-serif;
  --font-body:-apple-system,BlinkMacSystemFont,"Segoe UI","PingFang SC","Hiragino Sans GB","Microsoft YaHei","Noto Sans SC",sans-serif;
  --font-num:ui-monospace,"JetBrains Mono","SFMono-Regular",Menlo,Consolas,"Courier New",monospace;

  /* 节奏 */
  --ease:cubic-bezier(.22,.61,.36,1);
  --dur:220ms;
  --gap:24px;
  --wrap:1280px;

  /* 形状 */
  --shape-cut:polygon(15px 0%,100% 0%,100% calc(100% - 15px),calc(100% - 15px) 100%,0% 100%,0% 15px);
}

body{
  margin:0;
  min-height:100%;
  background-color:var(--ink);
  background-image:
    radial-gradient(1100px 560px at 8% -6%,rgba(37,232,201,.10),transparent 62%),
    radial-gradient(900px 520px at 104% 2%,rgba(255,138,61,.09),transparent 60%);
  background-repeat:no-repeat;
  background-attachment:fixed;
  color:var(--paper);
  font-family:var(--font-body);
  font-size:17px;
  line-height:1.7;
  letter-spacing:.01em;
  -webkit-font-smoothing:antialiased;
  -moz-osx-font-smoothing:grayscale;
}

img,svg,video{max-width:100%;display:block}
h1,h2,h3,h4,h5{
  margin:0 0 .6em;
  font-family:var(--font-head);
  font-weight:700;
  line-height:1.15;
  letter-spacing:-.015em;
  color:var(--paper);
  text-wrap:balance;
}
h1{font-size:clamp(32px,5.6vw,62px);font-weight:800}
h2{font-size:clamp(24px,3.4vw,38px)}
h3{font-size:clamp(19px,2.2vw,26px)}
h4{font-size:clamp(17px,1.8vw,20px)}
p{margin:0 0 1em}
p:last-child{margin-bottom:0}
ul,ol{margin:0 0 1em;padding-left:1.25em}
li{margin:.25em 0}
a{color:var(--cyan);text-decoration:none;transition:color var(--dur) var(--ease)}
a:hover{color:var(--orange)}
strong{font-weight:700}
::selection{background:var(--cyan);color:var(--ink)}
:focus-visible{outline:2px solid var(--cyan);outline-offset:3px;border-radius:2px}

/* ---------- 布局工具 ---------- */
.wrap{
  width:100%;
  max-width:var(--wrap);
  margin-inline:auto;
  padding-inline:clamp(16px,3.6vw,44px);
}
.page-main{padding-top:clamp(20px,3vw,40px)}
#main-content{scroll-margin-top:130px}
.stack > * + *{margin-top:var(--gap)}
.cluster{display:flex;flex-wrap:wrap;align-items:center;gap:12px}
.grid{display:grid;gap:var(--gap)}
.grid--2{grid-template-columns:repeat(auto-fit,minmax(280px,1fr))}
.grid--3{grid-template-columns:repeat(auto-fit,minmax(230px,1fr))}
.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:clamp(16px,3.6vw,44px);
  top:-90px;
  z-index:400;
  display:inline-block;
  padding:12px 22px;
  background:var(--cyan);
  color:var(--ink);
  font-family:var(--font-head);
  font-weight:700;
  font-size:15px;
  letter-spacing:.04em;
  border-radius:0 0 8px 8px;
  transition:top var(--dur) var(--ease);
}
.skip-link:focus,
.skip-link:focus-visible{
  top:12px;
  color:var(--ink);
  outline:none;
  box-shadow:inset 0 0 0 2px var(--ink);
}

/* ============================================================
   头部
   ============================================================ */
.site-head{
  position:sticky;
  top:0;
  z-index:120;
  background:rgba(13,21,48,.96);
  border-bottom:1px solid var(--line);
  transition:box-shadow var(--dur) var(--ease),border-color var(--dur) var(--ease);
}
@supports (backdrop-filter:blur(8px)){
  .site-head{
    background:rgba(13,21,48,.86);
    backdrop-filter:blur(10px) saturate(140%);
    -webkit-backdrop-filter:blur(10px) saturate(140%);
  }
}
.site-head.is-scrolled{
  box-shadow:0 12px 30px rgba(3,7,20,.55);
  border-bottom-color:#3B4870;
}

/* 品牌轨道 */
.head-rail{
  background:linear-gradient(90deg,rgba(24,35,76,.88),rgba(24,35,76,.30));
  border-bottom:1px solid var(--line);
}
.rail-inner{
  display:flex;
  align-items:center;
  gap:16px;
  min-height:70px;
}
.brand{
  display:inline-flex;
  align-items:center;
  gap:12px;
  flex:0 0 auto;
  min-width:0;
  color:inherit;
  text-decoration:none;
}
.brand:hover{color:inherit}
.brand-mark{
  flex:0 0 auto;
  display:grid;
  place-items:center;
  width:42px;
  height:42px;
  background:linear-gradient(145deg,var(--cyan),#118F7D 92%);
  color:var(--ink);
  font-family:var(--font-num);
  font-weight:700;
  font-size:15px;
  letter-spacing:-.02em;
  clip-path:polygon(9px 0%,100% 0%,100% calc(100% - 9px),calc(100% - 9px) 100%,0% 100%,0% 9px);
}
.brand-text{
  display:flex;
  flex-direction:column;
  gap:1px;
  min-width:0;
}
.brand-name{
  display:inline-flex;
  align-items:center;
  gap:9px;
  font-family:var(--font-head);
  font-weight:800;
  font-size:20px;
  line-height:1.2;
  letter-spacing:.01em;
  color:var(--paper);
}
.brand-tagline{
  font-family:var(--font-num);
  font-size:11px;
  font-weight:500;
  line-height:1;
  letter-spacing:.16em;
  text-transform:uppercase;
  color:var(--orange);
  border:1px solid rgba(255,138,61,.45);
  padding:3px 6px;
}
.brand-tag{
  font-size:12.5px;
  line-height:1.3;
  color:var(--mist);
  white-space:nowrap;
  overflow:hidden;
  text-overflow:ellipsis;
}
.rail-meta{
  margin-left:auto;
  display:flex;
  align-items:center;
  gap:14px;
}
.rail-link{
  padding:7px 12px;
  border:1px dashed rgba(142,155,187,.35);
  border-radius:2px;
  font-family:var(--font-num);
  font-size:12.5px;
  letter-spacing:.02em;
  color:var(--mist);
  transition:color var(--dur) var(--ease),border-color var(--dur) var(--ease);
}
.rail-link:hover{
  color:var(--cyan);
  border-color:var(--cyan);
  border-style:solid;
}

/* 移动导航按钮 */
.nav-toggle{
  display:none;
  align-items:center;
  gap:9px;
  margin-left:auto;
  padding:9px 14px;
  background:transparent;
  border:1px solid var(--line);
  border-radius:2px;
  color:var(--paper);
  cursor:pointer;
  font-family:var(--font-num);
  font-size:12px;
  letter-spacing:.14em;
  text-transform:uppercase;
  transition:border-color var(--dur) var(--ease),color var(--dur) var(--ease),background-color var(--dur) var(--ease);
}
.nav-toggle:hover{border-color:var(--cyan);color:var(--cyan)}
.nav-toggle[aria-expanded="true"]{
  border-color:var(--orange);
  color:var(--orange);
  background:rgba(255,138,61,.10);
}
.nav-toggle-icon{display:grid;gap:5px;width:16px}
.nav-toggle-bar{
  display:block;
  height:2px;
  width:100%;
  background:currentColor;
  transition:transform var(--dur) var(--ease);
}
.nav-toggle[aria-expanded="true"] .nav-toggle-bar:nth-child(1){transform:translateY(3.5px) rotate(45deg)}
.nav-toggle[aria-expanded="true"] .nav-toggle-bar:nth-child(2){transform:translateY(-3.5px) rotate(-45deg)}
.nav-toggle-label{line-height:1}

/* 导航主体 */
.site-nav{
  position:relative;
  background:transparent;
}
.nav-inner{display:flex;align-items:stretch}
.nav-list{
  display:flex;
  align-items:stretch;
  gap:0;
  width:100%;
  margin:0;
  padding:0;
  list-style:none;
}
.nav-item{margin:0}
.nav-link{
  position:relative;
  display:flex;
  align-items:baseline;
  gap:9px;
  padding:13px 18px 15px;
  color:var(--mist);
  text-decoration:none;
  font-family:var(--font-head);
  font-weight:700;
  font-size:16px;
  letter-spacing:.05em;
  transition:color var(--dur) var(--ease),background-color var(--dur) var(--ease);
}
.nav-link:hover,
.nav-link:focus-visible{
  color:var(--paper);
  background:rgba(46,58,94,.45);
}
.nav-idx{
  font-family:var(--font-num);
  font-size:10.5px;
  font-weight:500;
  letter-spacing:.02em;
  color:#48557D;
  transition:color var(--dur) var(--ease);
}
.nav-link:hover .nav-idx{color:var(--mist)}
.nav-label{line-height:1.2;white-space:nowrap}
.nav-link[aria-current="page"]{
  color:var(--cyan);
  background:rgba(37,232,201,.07);
}
.nav-link[aria-current="page"] .nav-idx{color:var(--orange)}
.nav-link[aria-current="page"]::after{
  content:"";
  position:absolute;
  left:18px;
  right:18px;
  bottom:0;
  height:3px;
  background:linear-gradient(90deg,var(--cyan),var(--orange));
}

/* 阅读进度 */
.scroll-track{
  position:absolute;
  left:0;
  right:0;
  bottom:0;
  height:2px;
  overflow:hidden;
  pointer-events:none;
  z-index:2;
}
.scroll-fill{
  display:block;
  height:100%;
  width:0;
  background:linear-gradient(90deg,var(--cyan),var(--orange));
  transition:width 90ms linear;
}

/* ============================================================
   页脚
   ============================================================ */
.site-foot{
  position:relative;
  margin-top:clamp(64px,9vw,128px);
  background:linear-gradient(180deg,#0B1229,#080D1F 100%);
  border-top:1px solid var(--line);
}
.site-foot::before{
  content:"";
  position:absolute;
  top:-1px;
  left:0;
  right:0;
  height:2px;
  background:linear-gradient(90deg,var(--cyan) 0%,var(--orange) 38%,transparent 82%);
  opacity:.85;
}
.foot-grid{
  display:grid;
  grid-template-columns:minmax(0,1.5fr) repeat(3,minmax(0,1fr));
  gap:clamp(28px,4vw,56px);
  padding-block:clamp(40px,6vw,72px) clamp(28px,4vw,48px);
}
.foot-brand{min-width:0}
.foot-mark{
  margin:0 0 12px;
  font-family:var(--font-head);
  font-weight:800;
  font-size:24px;
  letter-spacing:.04em;
  color:var(--paper);
}
.foot-claim{
  margin:0 0 14px;
  font-family:var(--font-num);
  font-size:13px;
  letter-spacing:.06em;
  color:var(--orange);
}
.foot-note{
  max-width:34ch;
  margin:0 0 18px;
  font-size:14px;
  line-height:1.75;
  color:var(--mist);
}
.foot-cta{margin-top:6px}
.foot-col{min-width:0}
.foot-col-title{
  display:flex;
  align-items:center;
  gap:8px;
  margin:0 0 14px;
  font-family:var(--font-num);
  font-size:12px;
  font-weight:600;
  letter-spacing:.18em;
  text-transform:uppercase;
  color:var(--mist);
}
.foot-col-title::before{
  content:"";
  flex:0 0 auto;
  width:9px;
  height:2px;
  background:var(--cyan);
}
.foot-list{margin:0;padding:0;list-style:none}
.foot-list li{margin:0}
.foot-link{
  display:inline-block;
  padding:5px 0;
  color:#B9C4DE;
  font-size:15px;
  text-decoration:none;
  transition:color var(--dur) var(--ease),transform var(--dur) var(--ease);
}
.foot-link:hover{color:var(--cyan);transform:translateX(3px)}
.foot-base{
  display:flex;
  flex-wrap:wrap;
  align-items:baseline;
  gap:6px 30px;
  padding-block:22px 34px;
  border-top:1px solid rgba(46,58,94,.7);
  font-size:13px;
  line-height:1.7;
  color:var(--mist);
}
.foot-base p{margin:0}
.foot-line{
  font-family:var(--font-num);
  letter-spacing:.01em;
}
.foot-line--addr{color:#7F8CAE}
.foot-line--icp{margin-left:auto;color:#6C7A9E}
.foot-base a{color:#B9C4DE}
.foot-base a:hover{color:var(--cyan)}

/* ============================================================
   通用组件
   ============================================================ */

/* 按钮 */
.btn{
  display:inline-flex;
  align-items:center;
  justify-content:center;
  gap:10px;
  padding:12px 22px;
  background:transparent;
  border:1px solid transparent;
  border-radius:2px;
  color:var(--paper);
  font-family:var(--font-head);
  font-weight:700;
  font-size:15px;
  letter-spacing:.06em;
  line-height:1.2;
  text-decoration:none;
  cursor:pointer;
  transition:transform var(--dur) var(--ease),background-color var(--dur) var(--ease),color var(--dur) var(--ease),border-color var(--dur) var(--ease);
}
.btn:hover{transform:translateY(-2px);text-decoration:none}
.btn:active{transform:translateY(0)}
.btn--primary{background:var(--orange);color:var(--brown)}
.btn--primary:hover{background:#FFA063;color:var(--brown)}
.btn--cyan{background:var(--cyan);color:var(--ink)}
.btn--cyan:hover{background:#5CF0DA;color:var(--ink)}
.btn--ghost{border-color:var(--line);color:var(--paper)}
.btn--ghost:hover{border-color:var(--cyan);color:var(--cyan)}
.btn--quiet{
  padding:8px 14px;
  border-color:var(--line);
  color:var(--mist);
  font-family:var(--font-num);
  font-size:12.5px;
  letter-spacing:.1em;
  text-transform:uppercase;
}
.btn--quiet:hover{color:var(--cyan);border-color:var(--cyan)}
.btn--primary::after,
.btn--cyan::after{
  content:"→";
  font-family:var(--font-num);
  font-weight:400;
  opacity:.75;
  transition:transform var(--dur) var(--ease);
}
.btn--primary:hover::after,
.btn--cyan:hover::after{transform:translateX(3px)}

/* 面包屑 */
.crumb{padding-block:20px 4px}
.crumb-list{
  display:flex;
  flex-wrap:wrap;
  align-items:center;
  gap:10px;
  margin:0;
  padding:0;
  list-style:none;
  font-family:var(--font-num);
  font-size:12.5px;
  letter-spacing:.02em;
}
.crumb-item{
  display:inline-flex;
  align-items:center;
  margin:0;
  color:var(--mist);
}
.crumb-item + .crumb-item::before{
  content:"/";
  margin-right:10px;
  color:#3F4C74;
}
.crumb-link{color:var(--mist);text-decoration:none}
.crumb-link:hover{color:var(--cyan)}
.crumb-current{color:var(--paper)}

/* 眉题与章节头 */
.eyebrow{
  display:inline-block;
  margin-bottom:10px;
  font-family:var(--font-num);
  font-size:11.5px;
  font-weight:600;
  letter-spacing:.2em;
  text-transform:uppercase;
  color:var(--orange);
}
.section-head{
  position:relative;
  display:flex;
  flex-wrap:wrap;
  align-items:flex-end;
  justify-content:space-between;
  gap:14px 24px;
  padding-bottom:16px;
  margin-bottom:clamp(20px,2.6vw,32px);
  border-bottom:1px solid var(--line);
}
.section-head::after{
  content:"";
  position:absolute;
  left:0;
  bottom:-1px;
  width:72px;
  height:3px;
  background:linear-gradient(90deg,var(--cyan),var(--orange));
}
.section-title{margin:0;font-size:clamp(22px,2.8vw,32px)}
.section-note{
  max-width:46ch;
  margin:0;
  font-size:14px;
  line-height:1.7;
  color:var(--mist);
}

/* 切角面板 */
.panel{
  --panel-bg:var(--ink-2);
  position:relative;
  background-color:transparent;
  background-image:linear-gradient(135deg,transparent 20px,var(--panel-bg) 20.5px);
  background-repeat:no-repeat;
  padding:clamp(20px,2.6vw,32px);
}
.panel--cream{--panel-bg:var(--cream);color:var(--brown)}
.panel--cream h1,
.panel--cream h2,
.panel--cream h3,
.panel--cream h4{color:var(--brown)}
.panel--flush{padding:0}
.panel--edge{--panel-bg:var(--ink-2);box-shadow:inset 3px 0 0 var(--cyan)}

/* 奶油纸正文容器 */
.prose{
  background-color:transparent;
  background-image:linear-gradient(135deg,transparent 22px,var(--cream) 22.5px);
  background-repeat:no-repeat;
  color:var(--brown);
  padding:clamp(24px,3.4vw,52px);
  font-size:17px;
  line-height:1.8;
}
.prose > * + *{margin-top:1em}
.prose h2{
  font-size:clamp(22px,2.6vw,30px);
  margin-top:1.6em;
  margin-bottom:.5em;
  color:var(--brown);
}
.prose h3{
  font-size:clamp(18px,2vw,22px);
  margin-top:1.4em;
  margin-bottom:.4em;
  color:var(--brown);
}
.prose a{
  color:var(--rust);
  text-decoration:underline;
  text-decoration-thickness:1px;
  text-underline-offset:3px;
}
.prose a:hover{color:#B93E1E}
.prose ul,.prose ol{padding-left:1.25em}
.prose strong{font-weight:700;color:var(--brown)}
.prose code{
  font-family:var(--font-num);
  font-size:.92em;
  background:rgba(21,16,12,.08);
  padding:2px 6px;
  border-radius:3px;
}
.prose blockquote{
  margin:1.6em 0;
  padding:6px 0 6px 20px;
  border-left:3px solid var(--rust);
  color:#3B2A1F;
}
.prose hr{
  margin:2em 0;
  border:0;
  border-top:1px solid rgba(21,16,12,.2);
}

/* 卡片流 */
.card-grid{
  display:grid;
  gap:var(--gap);
  grid-template-columns:repeat(auto-fill,minmax(270px,1fr));
}
.card{
  --card-bg:var(--ink-2);
  position:relative;
  display:flex;
  flex-direction:column;
  gap:10px;
  padding:clamp(16px,2vw,22px);
  background-color:transparent;
  background-image:linear-gradient(135deg,transparent 18px,var(--card-bg) 18.5px);
  background-repeat:no-repeat;
  color:inherit;
  text-decoration:none;
  transition:transform var(--dur) var(--ease),background-color var(--dur) var(--ease);
}
.card:hover{
  --card-bg:var(--ink-3);
  transform:translateY(-2px);
  color:inherit;
  text-decoration:none;
}
.card-title{
  margin:0;
  font-family:var(--font-head);
  font-weight:700;
  font-size:18px;
  line-height:1.35;
}
.card-meta{
  margin:0;
  font-family:var(--font-num);
  font-size:12px;
  letter-spacing:.06em;
  color:var(--mist);
}
.card-text{
  margin:0;
  font-size:14.5px;
  line-height:1.7;
  color:#A9B5D2;
}

/* 悬浮微面板 */
.micro-panel{
  position:absolute;
  top:12px;
  right:12px;
  display:inline-flex;
  align-items:center;
  gap:8px;
  padding:6px 10px;
  background:rgba(9,14,33,.94);
  border-left:2px solid var(--cyan);
  font-family:var(--font-num);
  font-size:11.5px;
  letter-spacing:.04em;
  color:var(--cyan);
  opacity:0;
  transform:translateY(-4px);
  pointer-events:none;
  transition:opacity var(--dur) var(--ease),transform var(--dur) var(--ease);
}
.card:hover .micro-panel,
.card:focus-visible .micro-panel,
.card:focus-within .micro-panel{
  opacity:1;
  transform:none;
}

/* 标签 */
.tag{
  display:inline-flex;
  align-items:center;
  gap:6px;
  padding:3px 9px;
  border:1px solid rgba(37,232,201,.35);
  border-radius:2px;
  font-family:var(--font-num);
  font-size:11.5px;
  line-height:1.6;
  letter-spacing:.08em;
  text-transform:uppercase;
  color:var(--cyan);
  background:rgba(37,232,201,.12);
}
.tag--orange{
  color:var(--orange);
  background:rgba(255,138,61,.13);
  border-color:rgba(255,138,61,.4);
}
.tag--mist{
  color:var(--mist);
  background:rgba(142,155,187,.12);
  border-color:rgba(142,155,187,.3);
}
.tag--rust{
  color:#FF8E6B;
  background:rgba(224,83,47,.16);
  border-color:rgba(224,83,47,.45);
}

/* 数据点 */
.stat{
  display:flex;
  flex-direction:column;
  gap:2px;
}
.stat-num{
  font-family:var(--font-num);
  font-variant-numeric:tabular-nums;
  font-size:clamp(24px,3vw,34px);
  font-weight:700;
  line-height:1.1;
  color:var(--cyan);
}
.stat-label{
  font-family:var(--font-num);
  font-size:11.5px;
  letter-spacing:.14em;
  text-transform:uppercase;
  color:var(--mist);
}

/* 图片容器基础 */
.media{
  position:relative;
  display:block;
  overflow:hidden;
  background-color:#101A3E;
  background-image:linear-gradient(155deg,#101A3E,#1B2750 55%,#22305F);
  clip-path:var(--shape-cut);
}
.media > img,
.media > video,
.media > picture > img{
  width:100%;
  height:100%;
  object-fit:cover;
  display:block;
}
.media--16x9{aspect-ratio:16/9}
.media--4x3{aspect-ratio:4/3}
.media--3x2{aspect-ratio:3/2}
.media--1x1{aspect-ratio:1/1}
.media--21x9{aspect-ratio:21/9}
.media--grid::after{
  content:"";
  position:absolute;
  inset:0;
  pointer-events:none;
  background-image:
    linear-gradient(rgba(142,155,187,.13) 1px,transparent 1px),
    linear-gradient(90deg,rgba(142,155,187,.13) 1px,transparent 1px);
  background-size:34px 34px;
  -webkit-mask-image:radial-gradient(120% 100% at 30% 8%,#000 40%,transparent 100%);
  mask-image:radial-gradient(120% 100% at 30% 8%,#000 40%,transparent 100%);
}
.media-caption{
  position:absolute;
  left:12px;
  bottom:10px;
  padding:4px 9px;
  background:rgba(9,14,33,.86);
  color:var(--mist);
  font-family:var(--font-num);
  font-size:11.5px;
  letter-spacing:.06em;
}

/* 复古双细线分隔 */
.rule{
  height:4px;
  margin:clamp(28px,4vw,52px) 0;
  border:0;
  border-top:1px solid var(--line);
  border-bottom:1px solid var(--line);
  opacity:.9;
}

/* 滚动显现协议 */
.js [data-reveal]{
  opacity:0;
  transform:translateY(10px);
  transition:opacity 280ms var(--ease),transform 280ms var(--ease);
}
.js [data-reveal][data-revealed]{
  opacity:1;
  transform:none;
}

/* ============================================================
   响应式
   ============================================================ */
@media (max-width:1080px){
  .foot-grid{grid-template-columns:minmax(0,1.2fr) repeat(3,minmax(0,.8fr));gap:32px}
}

@media (max-width:960px){
  .nav-toggle{display:inline-flex}
  .site-nav{
    max-height:0;
    overflow:hidden;
    background:#131D40;
    border-top:1px solid transparent;
    transition:max-height 280ms var(--ease),border-color var(--dur) var(--ease);
  }
  .site-nav[data-open]{
    max-height:min(560px,80vh);
    overflow:auto;
    border-top-color:var(--line);
  }
  .nav-inner{display:block}
  .nav-list{flex-direction:column;padding:6px 0 14px}
  .nav-link{
    padding:14px clamp(16px,3.6vw,44px);
    font-size:17px;
    border-bottom:1px solid rgba(46,58,94,.55);
  }
  .nav-link[aria-current="page"]{background:rgba(37,232,201,.09)}
  .nav-link[aria-current="page"]::after{
    left:0;
    right:auto;
    top:12px;
    bottom:12px;
    width:3px;
    height:auto;
    background:var(--cyan);
  }
  .nav-idx{font-size:12px}
}

@media (max-width:860px){
  .foot-grid{
    grid-template-columns:repeat(2,minmax(0,1fr));
    gap:28px 24px;
  }
  .foot-brand{grid-column:1 / -1}
  .foot-note{max-width:none}
}

@media (max-width:720px){
  .rail-inner{min-height:60px;gap:10px}
  .brand-mark{width:36px;height:36px;font-size:13px}
  .brand-name{font-size:17px;gap:7px}
  .brand-tag{display:none}
  .brand-tagline{font-size:10px;letter-spacing:.12em;padding:2px 5px}
  .rail-meta{display:none}
  .nav-toggle{margin-left:auto;padding:8px 12px}
  .prose{padding:clamp(20px,5vw,30px);font-size:16.5px}
  .panel{padding:clamp(18px,5vw,24px)}
  #main-content{scroll-margin-top:110px}
}

@media (max-width:520px){
  .foot-grid{grid-template-columns:minmax(0,1fr)}
  .foot-line--icp{margin-left:0}
  .foot-base{gap:4px 16px;font-size:12.5px}
  .btn{padding:11px 18px;font-size:14.5px}
  .card-grid{grid-template-columns:minmax(0,1fr)}
}

/* ============================================================
   动效降级
   ============================================================ */
@media (prefers-reduced-motion:reduce){
  html{scroll-behavior:auto}
  *,*::before,*::after{
    transition-duration:.001ms !important;
    animation-duration:.001ms !important;
    animation-iteration-count:1 !important;
  }
  .js [data-reveal]{
    opacity:1 !important;
    transform:none !important;
  }
  .card:hover{transform:none}
  .btn:hover{transform:none}
  .foot-link:hover{transform:none}
  .micro-panel{transform:none}
  .scroll-fill{transition:none}
}