/* =========================================================
   302com看台 — /assets/site.css
   共享外壳：reset / 变量 / 中文排版 / 双层页头 / 四列页脚
   ========================================================= */

:root{
  /* 夜墨蓝底 + 霓虹青与琥珀金强调 */
  --ink-1000:#04070F;
  --ink-900:#070B18;
  --ink-800:#0F1730;
  --ink-700:#16214A;
  --line:#2A3A6B;
  --text:#E9EEF9;
  --text-soft:#CBD5EA;
  --muted:#93A2C2;
  --cyan:#22E1D6;
  --amber:#FFB545;
  --ice:#4FC3FF;
  --ember:#FF6B2C;

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

  --shell:1280px;
  --pad:clamp(18px,4vw,48px);
  --gap:clamp(14px,1.6vw,22px);
  --r-sm:8px;
  --r-md:14px;
  --r-lg:20px;
  --ease:cubic-bezier(.22,.61,.36,1);
}

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

html{
  -webkit-text-size-adjust:100%;
  scroll-behavior:smooth;
  background:var(--ink-900);
}

body{
  margin:0;
  background:var(--ink-900);
  color:var(--text);
  font-family:var(--font-sans);
  font-size:16px;
  line-height:1.75;
  letter-spacing:0;
  -webkit-font-smoothing:antialiased;
  text-rendering:optimizeLegibility;
}

img,picture,svg,video{max-width:100%;display:block;height:auto}
h1,h2,h3,h4,h5,h6{margin:0;font-weight:800;line-height:1.12;letter-spacing:-.02em}
p{margin:0}
ul,ol{margin:0;padding:0}
li{list-style:none}
a{color:var(--cyan);text-decoration:none;transition:color .16s var(--ease)}
a:hover{color:var(--cyan)}
button{font:inherit;color:inherit;background:none;border:0;padding:0;cursor:pointer}
table{border-collapse:collapse;width:100%}
hr{border:0;border-top:1px solid var(--line);margin:0}
strong{font-weight:700;color:var(--text)}

:focus-visible{outline:2px solid var(--cyan);outline-offset:2px;border-radius:4px}

#main-content{display:block;scroll-margin-top:96px}

/* ---------- 壳与区块 ---------- */
.shell{width:100%;max-width:var(--shell);margin-inline:auto;padding-inline:var(--pad)}

.section{padding-block:clamp(44px,7vw,88px)}
.section--tight{padding-block:clamp(26px,4vw,52px)}
.section__head{display:flex;flex-wrap:wrap;align-items:flex-end;gap:12px 30px;margin-bottom:clamp(20px,3vw,36px)}
.section__head > .eyebrow{flex:1 0 100%}

.skip-link{
  position:absolute;left:12px;top:-70px;z-index:300;
  padding:10px 16px;border-radius:var(--r-sm);
  background:var(--cyan);color:#04121A;font-weight:700;font-size:14px;
  transition:top .16s var(--ease);
}
.skip-link:focus{top:12px;color:#04121A}

/* ---------- 文字层级 ---------- */
.eyebrow{
  display:block;font-size:12px;letter-spacing:.2em;line-height:1.4;
  color:var(--cyan);text-transform:uppercase;
}
.display{
  font-size:clamp(38px,6.4vw,84px);
  line-height:1.04;
  font-weight:800;
  font-stretch:condensed;
  letter-spacing:-.02em;
}
.display--thin{font-weight:200;letter-spacing:.004em;line-height:1.06}
.h2{font-size:clamp(24px,2.6vw,36px);line-height:1.16}
.h3{font-size:clamp(17px,1.4vw,21px);line-height:1.32}
.lede{font-size:clamp(16px,1.1vw + 13px,20px);line-height:1.7;color:var(--muted);max-width:54ch}
.prose{max-width:68ch;font-size:clamp(16px,1vw + 13px,17.5px);line-height:1.8;color:var(--text-soft)}
.prose p + p{margin-top:1em}
.prose h3{margin-top:1.7em;margin-bottom:.5em;color:var(--text)}
.prose ul{list-style:disc;padding-left:1.25em;margin:.9em 0}
.prose ol{list-style:decimal;padding-left:1.5em;margin:.9em 0}
.prose li{margin:.34em 0}
.muted{color:var(--muted)}
.num{font-family:var(--font-mono);font-variant-numeric:tabular-nums;letter-spacing:-.02em}

/* ---------- 按钮 ---------- */
.btn{
  display:inline-flex;align-items:center;justify-content:center;gap:8px;
  min-height:44px;padding:10px 20px;border-radius:var(--r-sm);
  border:1px solid var(--line);background:var(--ink-700);color:var(--text);
  font-size:14px;font-weight:600;letter-spacing:.06em;text-align:center;
  transition:background-color .16s var(--ease),color .16s var(--ease),border-color .16s var(--ease),transform .16s var(--ease);
}
.btn:hover{border-color:var(--cyan);color:var(--cyan)}
.btn:active{transform:translateY(1px)}
.btn--primary{background:linear-gradient(118deg,var(--cyan),#12B9CC);border-color:transparent;color:#04121A;font-weight:800}
.btn--primary:hover{color:#04121A;filter:brightness(1.07)}
.btn--amber{background:var(--amber);border-color:transparent;color:#241503;font-weight:800}
.btn--amber:hover{color:#241503;filter:brightness(1.05)}
.btn--ghost{background:transparent}
.btn--block{width:100%}

/* ---------- 面包屑 ---------- */
.crumbs{padding-top:22px}
.crumbs__list{display:flex;flex-wrap:wrap;align-items:center;gap:10px;font-size:12px;letter-spacing:.16em;color:var(--muted)}
.crumbs__list a{color:var(--muted)}
.crumbs__list a:hover{color:var(--cyan)}
.crumbs__sep{color:var(--line)}
.crumbs__list [aria-current="page"]{color:var(--text)}

/* ---------- 网格与 Bento ---------- */
.grid{
  display:grid;
  grid-template-columns:repeat(12,minmax(0,1fr));
  gap:var(--gap);
}
.bento{
  display:grid;
  grid-template-columns:repeat(12,minmax(0,1fr));
  gap:var(--gap);
  align-items:start;
}
.grid--wide,.bento--wide{gap:clamp(18px,2.4vw,32px)}
.span-3{grid-column:span 3}
.span-4{grid-column:span 4}
.span-5{grid-column:span 5}
.span-6{grid-column:span 6}
.span-7{grid-column:span 7}
.span-8{grid-column:span 8}
.span-9{grid-column:span 9}
.span-12{grid-column:span 12}

/* ---------- 面板与纸张叠层 ---------- */
.panel{
  position:relative;
  background:var(--ink-800);
  border:1px solid var(--line);
  border-radius:var(--r-md);
  padding:clamp(18px,2.2vw,28px);
}
.panel--sunken{background:var(--ink-900)}
.panel--raise{background:var(--ink-700)}
.panel--focus{
  border-color:rgba(34,225,214,.5);
  box-shadow:0 0 0 1px rgba(34,225,214,.12),0 30px 70px -50px rgba(34,225,214,.75);
}
.panel--amber{border-color:rgba(255,181,69,.45)}
.panel__head{display:flex;align-items:baseline;justify-content:space-between;gap:12px;margin-bottom:14px}
.panel__kicker{font-size:12px;letter-spacing:.18em;color:var(--muted)}

.paper{position:relative;isolation:isolate}
.paper::after{
  content:"";position:absolute;inset:10px -10px -10px 10px;
  border:1px solid var(--line);border-radius:var(--r-md);
  z-index:-1;pointer-events:none;
}

/* ---------- 数字锚点 ---------- */
.stat{display:flex;flex-direction:column;gap:6px}
.stat__num{
  font-family:var(--font-mono);font-variant-numeric:tabular-nums;
  font-size:clamp(30px,4.4vw,54px);line-height:1;font-weight:700;
  color:var(--amber);letter-spacing:-.02em;
}
.stat__num--cyan{color:var(--cyan)}
.stat__label{font-size:12px;letter-spacing:.16em;color:var(--muted)}

/* ---------- 标签 ---------- */
.tag{
  display:inline-flex;align-items:center;gap:6px;
  padding:3px 10px;border:1px solid var(--line);border-radius:999px;
  font-size:11px;letter-spacing:.14em;line-height:1.6;
  color:var(--muted);background:rgba(22,33,74,.7);white-space:nowrap;
}
.tag--cyan{background:var(--cyan);border-color:var(--cyan);color:#04121A;font-weight:700}
.tag--amber{background:var(--amber);border-color:var(--amber);color:#241503;font-weight:700}
.tag--outline{background:transparent;border-color:rgba(34,225,214,.55);color:var(--cyan)}

/* ---------- 冷热映射与热力块 ---------- */
.scale{display:flex;align-items:center;gap:10px;font-size:11px;letter-spacing:.14em;color:var(--muted)}
.scale__bar{
  flex:1 1 auto;height:6px;border-radius:999px;
  background:linear-gradient(90deg,var(--ice),var(--cyan) 44%,var(--amber) 74%,var(--ember));
}
.heat{display:flex;flex-wrap:wrap;gap:6px}
.heat__cell{
  width:34px;height:34px;border-radius:6px;border:1px solid var(--line);
  display:flex;align-items:center;justify-content:center;
  font-family:var(--font-mono);font-size:12px;color:var(--text);
  background:rgba(79,195,255,.12);
}
.heat__cell--l1{background:rgba(79,195,255,.2)}
.heat__cell--l2{background:rgba(34,225,214,.24)}
.heat__cell--l3{background:rgba(255,181,69,.24)}
.heat__cell--l4{background:rgba(255,181,69,.4)}
.heat__cell--l5{background:rgba(255,107,44,.58);border-color:rgba(255,107,44,.8)}

/* ---------- 横向滚动带 ---------- */
.rail{
  position:relative;overflow-x:auto;overflow-y:hidden;
  scroll-snap-type:x proximity;-webkit-overflow-scrolling:touch;
  padding-bottom:10px;
  scrollbar-color:var(--line) transparent;
}
.rail__track{display:flex;gap:var(--gap);min-width:100%}
.rail__item{scroll-snap-align:start;flex:0 0 min(320px,82vw)}
.rail--edge{
  -webkit-mask-image:linear-gradient(90deg,transparent 0,#000 26px,#000 calc(100% - 26px),transparent 100%);
  mask-image:linear-gradient(90deg,transparent 0,#000 26px,#000 calc(100% - 26px),transparent 100%);
}

/* ---------- 表格 ---------- */
.table-wrap{overflow-x:auto;border:1px solid var(--line);border-radius:var(--r-sm);-webkit-overflow-scrolling:touch}
.table{width:100%;min-width:520px;font-size:14px}
.table th,.table td{padding:11px 14px;text-align:left;border-bottom:1px solid var(--line)}
.table th{font-size:11px;letter-spacing:.16em;font-weight:600;color:var(--muted);background:var(--ink-700)}
.table td{color:var(--text-soft)}
.table tr:last-child td{border-bottom:0}
.table .num{color:var(--amber)}

/* ---------- 图片 / 图形占位容器 ---------- */
.media{
  position:relative;overflow:hidden;display:block;
  border:1px solid var(--line);border-radius:var(--r-md);
  background:linear-gradient(140deg,var(--ink-700),var(--ink-900));
  aspect-ratio:16/9;
}
.media--4x3{aspect-ratio:4/3}
.media--3x2{aspect-ratio:3/2}
.media--1x1{aspect-ratio:1/1}
.media--tall{aspect-ratio:3/4}
.media > img,.media > svg,.media > picture > img{width:100%;height:100%;object-fit:cover}
.media__cap{
  position:absolute;left:12px;right:12px;bottom:12px;
  padding:5px 9px;border:1px solid var(--line);border-radius:6px;
  background:rgba(7,11,24,.72);backdrop-filter:blur(6px);
  font-size:11px;letter-spacing:.14em;color:var(--text);
}
.media__tag{position:absolute;top:12px;left:12px}

/* ---------- 横向主题带 ---------- */
.band{
  border-top:1px solid var(--line);border-bottom:1px solid var(--line);
  background:linear-gradient(90deg,rgba(34,225,214,.09),transparent 44%,rgba(255,181,69,.09));
}
.band__inner{display:flex;align-items:center;gap:clamp(12px,2.4vw,30px);padding-block:14px;overflow-x:auto}
.band__item{display:inline-flex;align-items:center;gap:8px;font-size:12px;letter-spacing:.16em;color:var(--muted);white-space:nowrap}
.band__item i{display:block;width:22px;height:3px;border-radius:2px;background:var(--cyan)}
.band__item--amber i{background:var(--amber);width:38px}
.band__item--ice i{background:var(--ice);width:14px}

/* ---------- 阅读进度 ---------- */
.scroll-progress{
  position:fixed;top:0;left:0;width:100%;height:2px;z-index:250;
  transform:scaleX(0);transform-origin:0 50%;pointer-events:none;
  background:linear-gradient(90deg,var(--ice),var(--cyan) 44%,var(--amber) 80%,var(--ember));
}

/* ---------- 滚动显现 ---------- */
.has-js [data-reveal]{opacity:0;transform:translateY(14px)}
.has-js [data-reveal].is-visible{
  opacity:1;transform:none;
  transition:opacity .34s var(--ease),transform .34s var(--ease);
}

/* =========================================================
   页头：双层信息导航
   ========================================================= */
.site-header{position:sticky;top:0;z-index:120;background:var(--ink-900)}
.site-header::after{content:"";display:block;height:1px;background:var(--line)}

/* 上层品牌说明条 */
.brand-strip{
  background:var(--ink-800);
  border-bottom:1px solid var(--line);
  overflow:hidden;
  max-height:70px;
  transition:max-height .28s var(--ease),opacity .2s var(--ease),border-color .2s var(--ease);
}
.site-header[data-condensed] .brand-strip{max-height:0;opacity:0;border-bottom-color:transparent}
.brand-strip__inner{display:flex;align-items:center;gap:clamp(12px,3vw,34px);min-height:44px;padding-block:9px}
.brand-strip__brand{
  font-size:15px;font-weight:800;letter-spacing:.06em;color:var(--text);white-space:nowrap;
}
.brand-strip__brand span{color:var(--cyan)}
.brand-strip__brand:hover{color:var(--text)}
.brand-strip__value{margin:0;font-size:12px;letter-spacing:.2em;color:var(--muted);white-space:nowrap}
.brand-strip__links{margin-left:auto;display:flex;align-items:center;gap:clamp(10px,2vw,24px);font-size:12px;letter-spacing:.08em}
.brand-strip__meta{display:inline-flex;align-items:center;gap:8px;color:var(--muted);white-space:nowrap}
.brand-strip__tel{
  display:inline-flex;align-items:center;min-height:28px;padding:2px 12px;
  border:1px solid var(--line);border-radius:999px;
  font-family:var(--font-mono);color:var(--muted);
}
.brand-strip__tel:hover{border-color:var(--cyan);color:var(--cyan)}
.dot{width:6px;height:6px;border-radius:50%;background:var(--cyan);box-shadow:0 0 0 3px rgba(34,225,214,.16);flex:0 0 auto}

/* 下层常驻栏目 */
.mainnav{position:relative;background:rgba(7,11,24,.94);backdrop-filter:blur(10px)}
.mainnav__inner{display:flex;align-items:center;gap:clamp(10px,2vw,26px);min-height:58px}
.mainnav__list{display:flex;align-items:center;flex-wrap:wrap;gap:2px;flex:1 1 auto}
.mainnav__list a{
  display:block;padding:9px 14px;border-radius:var(--r-sm);
  font-size:15px;color:var(--muted);white-space:nowrap;
  transition:color .16s var(--ease),background-color .16s var(--ease);
}
.mainnav__list a:hover{color:var(--text);background:var(--ink-700)}
.mainnav__list a[aria-current="page"]{
  color:var(--cyan);font-weight:700;background:rgba(34,225,214,.07);
  box-shadow:inset 0 -2px 0 0 var(--cyan);
}
.mainnav__group{display:none}
.mainnav__foot{display:none}
.mainnav__cta{flex:0 0 auto}

/* 抽屉按钮 */
.nav-toggle{
  display:none;align-items:center;gap:10px;
  min-height:44px;padding:9px 13px;
  border:1px solid var(--line);border-radius:var(--r-sm);
  background:var(--ink-800);color:var(--text);
  font-size:12px;letter-spacing:.18em;
}
.nav-toggle__bars{position:relative;display:block;width:16px;height:2px;border-radius:2px;background:var(--cyan)}
.nav-toggle__bars::before,.nav-toggle__bars::after{
  content:"";position:absolute;left:0;width:16px;height:2px;border-radius:2px;
  background:var(--cyan);transition:transform .2s var(--ease);
}
.nav-toggle__bars::before{top:-5px}
.nav-toggle__bars::after{top:5px}
.nav-toggle[aria-expanded="true"] .nav-toggle__bars{background:transparent}
.nav-toggle[aria-expanded="true"] .nav-toggle__bars::before{transform:translateY(5px) rotate(45deg)}
.nav-toggle[aria-expanded="true"] .nav-toggle__bars::after{transform:translateY(-5px) rotate(-45deg)}

/* =========================================================
   页脚：四列 + 底部横向信息带
   ========================================================= */
.site-footer{
  margin-top:clamp(40px,6vw,80px);
  background:var(--ink-800);
  border-top:1px solid var(--line);
}
.footer__grid{
  display:grid;
  grid-template-columns:1.6fr 1fr 1fr 1fr;
  gap:clamp(20px,3vw,44px);
  padding-block:clamp(36px,5vw,60px) clamp(28px,4vw,44px);
}
.footer__brand{display:flex;flex-direction:column;gap:10px}
.footer__logo{font-size:20px;font-weight:800;letter-spacing:.06em;color:var(--text)}
.footer__logo:hover{color:var(--cyan)}
.footer__line{margin:0;font-size:12px;letter-spacing:.2em;color:var(--cyan)}
.footer__trust{margin:0;max-width:36ch;font-size:14px;line-height:1.8;color:var(--muted)}
.footer__col ul{display:flex;flex-direction:column;gap:10px}
.footer__title{margin:0 0 14px;font-size:11px;letter-spacing:.22em;color:var(--muted);text-transform:uppercase}
.footer__col a{font-size:15px;color:var(--muted)}
.footer__col a:hover{color:var(--text);text-decoration:underline;text-underline-offset:3px}

.footer__band{background:var(--ink-900);border-top:1px solid var(--line)}
.footer__band-inner{
  display:flex;flex-wrap:wrap;align-items:center;justify-content:space-between;
  gap:10px 26px;padding-block:16px;
  font-size:13px;color:var(--muted);
}
.footer__copy,.footer__icp,.footer__contact{margin:0}
.footer__icp{font-family:var(--font-mono);font-size:12px;letter-spacing:.02em}
.footer__contact{display:inline-flex;flex-wrap:wrap;align-items:center;gap:10px}
.footer__contact a{color:var(--text-soft)}
.footer__contact a:hover{color:var(--cyan)}

/* =========================================================
   响应式
   ========================================================= */
@media (max-width:1080px){
  .footer__grid{grid-template-columns:1.4fr 1fr 1fr 1fr;gap:22px}
}

@media (max-width:900px){
  :root{--pad:clamp(16px,4.4vw,28px)}

  .grid,.bento{grid-template-columns:repeat(6,minmax(0,1fr))}
  .span-3,.span-4{grid-column:span 3}
  .span-5,.span-6,.span-7,.span-8,.span-9,.span-12{grid-column:span 6}

  .display{font-size:clamp(32px,9vw,54px)}

  /* 双层导航折为抽屉 */
  .nav-toggle{display:inline-flex;order:1}
  .mainnav__inner{flex-wrap:wrap;min-height:56px}
  .mainnav__cta{order:2;margin-left:auto;min-height:40px;padding:8px 15px;font-size:13px}
  .mainnav__list{
    order:3;flex:1 0 100%;
    position:absolute;top:100%;left:0;right:0;
    display:none;flex-direction:column;align-items:stretch;gap:0;
    max-height:76vh;overflow-y:auto;
    padding:10px var(--pad) 22px;
    background:var(--ink-800);
    border-bottom:1px solid var(--line);
    box-shadow:0 34px 60px -32px rgba(0,0,0,.92);
  }
  [data-nav][data-open] .mainnav__list{display:flex}
  .mainnav__list a{
    padding:13px 6px;font-size:17px;border-radius:0;
    border-bottom:1px solid rgba(42,58,107,.62);
  }
  .mainnav__list a:hover{background:transparent;color:var(--cyan)}
  .mainnav__list a[aria-current="page"]{
    background:transparent;color:var(--cyan);
    box-shadow:inset 3px 0 0 0 var(--cyan);
    padding-left:14px;
  }
  .mainnav__group{
    display:block;padding:18px 6px 6px;
    font-size:11px;letter-spacing:.24em;color:var(--cyan);
  }
  .mainnav__group:first-child{padding-top:6px}
  .mainnav__foot{
    display:flex;flex-direction:column;gap:8px;
    padding:20px 6px 4px;
    border-top:1px dashed rgba(42,58,107,.7);
    margin-top:12px;
  }
  .mainnav__foot a{font-size:14px;color:var(--muted);text-decoration:underline;text-underline-offset:3px}
  .mainnav__foot a:hover{color:var(--cyan)}

  body.nav-open{overflow:hidden}

  .footer__grid{grid-template-columns:repeat(2,minmax(0,1fr));gap:28px 22px}
  .footer__brand{grid-column:1 / -1}
}

@media (max-width:760px){
  .brand-strip__value{display:none}
  .brand-strip__meta{display:none}
  .band__inner{padding-block:12px}
  .footer__band-inner{flex-direction:column;align-items:flex-start;gap:8px}
}

@media (max-width:600px){
  .grid,.bento{grid-template-columns:repeat(1,minmax(0,1fr))}
  .span-3,.span-4,.span-5,.span-6,.span-7,.span-8,.span-9,.span-12{grid-column:span 1}
  .footer__grid{grid-template-columns:1fr}
  .rail__item{flex:0 0 84vw}
  .table{min-width:460px}
}

/* 键盘与动效偏好 */
@media (prefers-reduced-motion:reduce){
  html{scroll-behavior:auto}
  *,*::before,*::after{
    animation-duration:.001ms !important;
    animation-iteration-count:1 !important;
    transition-duration:.001ms !important;
    scroll-behavior:auto !important;
  }
  .has-js [data-reveal]{opacity:1;transform:none}
  .scroll-progress{transition:none}
}