/* ============================================================
   百老汇牛牛游 · /assets/site.css
   共享外壳样式：reset、变量、中文排版、头部、页脚、通用组件
   ============================================================ */

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

:root{
  /* 色彩 */
  --ink:#07071A;
  --panel:#12122E;
  --indigo:#1C1A45;
  --neon:#A855F7;
  --neon-hi:#C084FC;
  --cyan:#2DE2E6;
  --gold:#FFB454;
  --gold-soft:#FFD166;
  --text:#F4F2FF;
  --muted:#A9A3CF;
  --green:#4ADE80;
  --rose:#FB7185;
  --line:rgba(169,163,207,.18);
  --line-strong:rgba(192,132,252,.42);

  /* 形状 */
  --radius-lg:26px;
  --radius-md:20px;
  --radius-sm:14px;
  --pill:999px;

  /* 尺度 */
  --shell:1180px;
  --shell-wide:1340px;
  --gutter:clamp(16px,4vw,40px);
  --header-offset:120px;

  /* 字体栈 */
  --font-sans:"Noto Sans SC","PingFang SC","Hiragino Sans GB","Microsoft YaHei",system-ui,-apple-system,"Segoe UI",Roboto,sans-serif;
  --font-mono:"JetBrains Mono",ui-monospace,SFMono-Regular,Menlo,Consolas,"Liberation Mono",monospace;
}

html{
  -webkit-text-size-adjust:100%;
  scroll-behavior:smooth;
  scroll-padding-top:calc(var(--header-offset) + 12px);
}

body{
  margin:0;
  min-height:100%;
  font-family:var(--font-sans);
  font-size:16.5px;
  line-height:1.75;
  font-weight:400;
  color:var(--text);
  background-color:var(--ink);
  background-image:
    radial-gradient(920px 540px at 88% -10%, rgba(168,85,247,.22), transparent 70%),
    radial-gradient(760px 460px at 2% 4%, rgba(45,226,230,.13), transparent 68%),
    radial-gradient(680px 420px at 52% 108%, rgba(255,180,84,.10), transparent 72%);
  background-attachment:fixed;
  -webkit-font-smoothing:antialiased;
}

img,svg,video{max-width:100%;display:block;height:auto}
ul,ol{margin:0;padding:0;list-style:none}
p{margin:0 0 1em;max-width:38em}
a{color:var(--neon-hi);text-decoration:none}
a:hover{color:var(--cyan)}
button{font:inherit;color:inherit}
dl,dd,dt{margin:0}

h1,h2,h3,h4{
  margin:0 0 .5em;
  font-weight:900;
  letter-spacing:-.02em;
  line-height:1.15;
  color:var(--text);
}
h1{font-size:clamp(28px,6vw,46px)}
h2{font-size:clamp(22px,3.4vw,30px)}
h3{font-size:clamp(18px,2.2px + 1vw,22px)}
h4{font-size:17px}

:focus-visible{
  outline:2px solid var(--cyan);
  outline-offset:3px;
  border-radius:6px;
}

/* ---------- 通用工具 ---------- */
.shell{
  width:100%;
  max-width:var(--shell);
  margin-inline:auto;
  padding-inline:var(--gutter);
}
.shell--wide{max-width:var(--shell-wide)}

.mono{
  font-family:var(--font-mono);
  font-weight:500;
  font-variant-numeric:tabular-nums;
  letter-spacing:.01em;
}

.kicker{
  display:inline-block;
  margin:0 0 10px;
  font-size:12.5px;
  font-weight:600;
  letter-spacing:.12em;
  text-transform:uppercase;
  color:var(--cyan);
}

.lede{
  font-size:clamp(17px,1.9vw,19px);
  line-height:1.7;
  color:var(--muted);
  max-width:34em;
}

.rule{
  height:1px;
  border:0;
  margin:0;
  background:linear-gradient(90deg,transparent,rgba(168,85,247,.55),rgba(45,226,230,.35),transparent);
}

.stack>*+*{margin-top:18px}

/* ---------- 12 列非对称栅格 ---------- */
.grid-12{
  display:grid;
  grid-template-columns:repeat(12,minmax(0,1fr));
  gap:clamp(16px,2.4vw,28px);
}
.col-4{grid-column:span 4}
.col-5{grid-column:span 5}
.col-6{grid-column:span 6}
.col-7{grid-column:span 7}
.col-8{grid-column:span 8}
.col-12{grid-column:span 12}

@media (max-width:900px){
  .col-4,.col-5,.col-6,.col-7,.col-8{grid-column:1 / -1}
}

/* ---------- 区块与编号章节 ---------- */
.section{padding-block:clamp(36px,6vw,72px)}

.chapter{
  position:relative;
  padding-block:clamp(26px,4vw,44px);
}
.chapter__no{
  display:block;
  margin:0 0 4px;
  font-family:var(--font-mono);
  font-weight:500;
  font-size:clamp(26px,4.6vw,40px);
  line-height:1;
  letter-spacing:.02em;
  color:var(--neon);
  text-shadow:0 0 24px rgba(168,85,247,.55);
}
.chapter__body{max-width:38em}

/* ---------- 卡片 / 面板 / 标签 ---------- */
.card{
  position:relative;
  background:linear-gradient(180deg,rgba(28,26,69,.72),rgba(18,18,46,.9));
  border:1px solid var(--line);
  border-radius:var(--radius-lg);
  padding:clamp(18px,2.4vw,26px);
  transition:border-color .22s ease,box-shadow .22s ease;
}
.card:hover{
  border-color:var(--line-strong);
  box-shadow:0 0 0 1px rgba(192,132,252,.25),0 14px 40px -18px rgba(168,85,247,.9);
}

.panel{
  background:var(--panel);
  border:1px solid var(--line);
  border-radius:var(--radius-md);
  padding:18px;
}

.tag{
  display:inline-flex;
  align-items:center;
  gap:6px;
  padding:4px 12px;
  border-radius:var(--pill);
  border:1px solid var(--line);
  font-size:12px;
  font-weight:600;
  letter-spacing:.12em;
  text-transform:uppercase;
  color:var(--muted);
  white-space:nowrap;
}
.tag--neon{color:var(--neon-hi);border-color:rgba(192,132,252,.45);background:rgba(168,85,247,.14)}
.tag--cyan{color:var(--cyan);border-color:rgba(45,226,230,.42);background:rgba(45,226,230,.1)}
.tag--gold{color:var(--gold-soft);border-color:rgba(255,209,102,.4);background:rgba(255,180,84,.1)}

/* ---------- 数据卡 ---------- */
.stat{
  background:linear-gradient(180deg,rgba(18,18,46,.95),rgba(28,26,69,.6));
  border:1px solid var(--line);
  border-radius:var(--radius-md);
  padding:16px 18px;
}
.stat__value{
  display:block;
  font-family:var(--font-mono);
  font-weight:500;
  font-size:clamp(24px,4vw,34px);
  line-height:1.1;
  color:var(--gold);
  font-variant-numeric:tabular-nums;
}
.stat__label{
  display:block;
  margin-top:6px;
  font-size:12px;
  font-weight:600;
  letter-spacing:.12em;
  text-transform:uppercase;
  color:var(--muted);
}

/* ---------- 按钮 ---------- */
.btn{
  display:inline-flex;
  align-items:center;
  gap:8px;
  padding:12px 22px;
  border-radius:var(--pill);
  border:1px solid transparent;
  font-size:15px;
  font-weight:700;
  line-height:1.2;
  cursor:pointer;
  transition:background .2s ease,border-color .2s ease,color .2s ease,box-shadow .2s ease;
}
.btn--primary{
  background:linear-gradient(120deg,var(--neon),#7C3AED);
  color:#fff;
  box-shadow:0 12px 32px -14px rgba(168,85,247,.95);
}
.btn--primary:hover{color:#fff;background:linear-gradient(120deg,var(--neon-hi),var(--neon))}
.btn--ghost{
  background:rgba(45,226,230,.08);
  border-color:rgba(45,226,230,.4);
  color:var(--cyan);
}
.btn--ghost:hover{background:rgba(45,226,230,.18);color:#7FF6F8}

/* ---------- 面包屑 ---------- */
.breadcrumbs{font-size:13px;color:var(--muted)}
.breadcrumbs ol{display:flex;flex-wrap:wrap;gap:8px;align-items:center}
.breadcrumbs li{display:flex;align-items:center;gap:8px}
.breadcrumbs li::after{content:"/";color:rgba(169,163,207,.42)}
.breadcrumbs li:last-child::after{content:""}
.breadcrumbs a{color:var(--muted)}
.breadcrumbs a:hover{color:var(--cyan)}
.breadcrumbs [aria-current="page"]{color:var(--gold-soft)}

/* ---------- 正文 ---------- */
.prose{max-width:38em}
.prose h2{margin-top:1.5em}
.prose h3{margin-top:1.3em}
.prose ul{list-style:disc;padding-left:1.25em;margin:0 0 1.2em}
.prose ol{list-style:decimal;padding-left:1.25em;margin:0 0 1.2em}
.prose li{margin-bottom:.45em}
.prose li::marker{color:var(--neon)}
.prose strong{color:var(--gold-soft);font-weight:700}

/* ---------- 分段控件骨架 ---------- */
.tabs{display:block}
.tabs__list{
  display:flex;
  gap:6px;
  padding:6px;
  overflow-x:auto;
  background:var(--indigo);
  border:1px solid var(--line);
  border-radius:var(--pill);
  scrollbar-width:thin;
}
.tabs__tab{
  flex:0 0 auto;
  padding:9px 18px;
  border:0;
  border-radius:var(--pill);
  background:transparent;
  color:var(--muted);
  font-size:14px;
  font-weight:600;
  white-space:nowrap;
  cursor:pointer;
  transition:background .18s ease,color .18s ease;
}
.tabs__tab:hover{color:var(--text);background:rgba(168,85,247,.14)}
.tabs__tab[aria-selected="true"]{
  background:linear-gradient(120deg,var(--neon),#7C3AED);
  color:#fff;
  box-shadow:0 8px 22px -10px rgba(168,85,247,.95);
}
.tabs__panel{margin-top:20px;animation:tab-in .18s ease both}
.tabs__panel[hidden]{display:none}

@keyframes tab-in{
  from{opacity:0;transform:translateY(6px)}
  to{opacity:1;transform:none}
}

/* ---------- 问答 ---------- */
.faq{
  background:var(--panel);
  border:1px solid var(--line);
  border-radius:var(--radius-md);
  padding:14px 18px;
}
.faq+.faq{margin-top:10px}
.faq summary{
  display:flex;
  align-items:center;
  justify-content:space-between;
  gap:12px;
  cursor:pointer;
  font-weight:700;
  list-style:none;
}
.faq summary::-webkit-details-marker{display:none}
.faq summary::after{
  content:"+";
  font-family:var(--font-mono);
  font-size:18px;
  color:var(--neon-hi);
}
.faq[open] summary::after{content:"–"}
.faq__body{margin-top:10px;color:var(--muted);max-width:38em}

/* ---------- 数据表 ---------- */
.data-table{
  width:100%;
  border-collapse:collapse;
  font-size:14.5px;
}
.data-table caption{
  text-align:left;
  padding-bottom:10px;
  font-size:12.5px;
  letter-spacing:.12em;
  text-transform:uppercase;
  color:var(--muted);
}
.data-table th{
  text-align:left;
  padding:10px 12px;
  font-size:12px;
  font-weight:600;
  letter-spacing:.12em;
  text-transform:uppercase;
  color:var(--muted);
  border-bottom:1px solid var(--line);
}
.data-table td{
  padding:12px;
  border-bottom:1px dashed rgba(169,163,207,.14);
  color:var(--text);
}
.data-table td.num{
  font-family:var(--font-mono);
  font-variant-numeric:tabular-nums;
  color:var(--gold-soft);
}

/* ---------- 图片容器（页面阶段放入 .media-frame__img 即可） ---------- */
.media-frame{
  position:relative;
  overflow:hidden;
  border-radius:var(--radius-lg);
  border:1px solid var(--line);
  background:
    linear-gradient(150deg,rgba(28,26,69,.92),rgba(7,7,26,.92)),
    radial-gradient(320px 200px at 70% 20%,rgba(45,226,230,.18),transparent 70%);
  aspect-ratio:16/9;
}
.media-frame--tall{aspect-ratio:4/5}
.media-frame--square{aspect-ratio:1/1}
.media-frame__img{
  width:100%;
  height:100%;
  object-fit:cover;
  display:block;
}
.media-frame__caption{
  position:absolute;
  inset:auto 0 0 0;
  padding:14px 16px;
  font-size:13px;
  line-height:1.5;
  color:var(--text);
  background:linear-gradient(180deg,transparent,rgba(7,7,26,.94));
}
.media-frame::after{
  content:"";
  position:absolute;
  inset:0;
  border-radius:inherit;
  box-shadow:inset 0 0 0 1px rgba(192,132,252,.28);
  pointer-events:none;
}

/* ============================================================
   头部
   ============================================================ */
.skip-link{
  position:absolute;
  left:16px;
  top:-70px;
  z-index:120;
  padding:10px 20px;
  border-radius:var(--pill);
  background:var(--neon);
  color:#0B0620;
  font-weight:700;
  transition:top .18s ease;
}
.skip-link:focus{top:12px;color:#0B0620}

.site-header{
  position:sticky;
  top:0;
  z-index:60;
  background:linear-gradient(180deg,rgba(7,7,26,.97),rgba(7,7,26,.9));
  backdrop-filter:blur(14px);
  -webkit-backdrop-filter:blur(14px);
  border-bottom:1px solid var(--line);
}

.brandbar{padding-block:12px}
.brandbar__inner{
  display:flex;
  align-items:center;
  justify-content:space-between;
  gap:16px;
}

.brand{
  display:inline-flex;
  align-items:center;
  gap:12px;
  color:var(--text);
  min-width:0;
}
.brand:hover{color:var(--text)}
.brand__mark{
  flex:0 0 auto;
  display:grid;
  place-items:center;
  width:40px;
  height:40px;
  border-radius:13px;
  background:linear-gradient(140deg,var(--neon),var(--cyan));
  color:#07071A;
  font-weight:900;
  font-size:19px;
  box-shadow:0 0 22px -6px rgba(168,85,247,.95);
}
.brand__text{display:flex;flex-direction:column;line-height:1.15;min-width:0}
.brand__name{
  font-weight:900;
  font-size:17px;
  letter-spacing:-.02em;
  white-space:nowrap;
}
.brand__tag{
  font-size:11.5px;
  font-weight:600;
  letter-spacing:.12em;
  color:var(--muted);
  white-space:nowrap;
}

.brandbar__side{
  display:flex;
  align-items:center;
  gap:10px;
  flex:0 0 auto;
}

.statusline{
  display:inline-flex;
  align-items:center;
  gap:8px;
  margin:0;
  padding:7px 14px;
  border-radius:var(--pill);
  border:1px solid var(--line);
  background:rgba(18,18,46,.7);
  font-size:12.5px;
  color:var(--muted);
}
.statusline__label{white-space:nowrap}
.dot{
  width:8px;
  height:8px;
  border-radius:50%;
  background:var(--green);
  box-shadow:0 0 0 4px rgba(74,222,128,.16);
  animation:pulse 2.4s ease-in-out infinite;
}
@keyframes pulse{
  0%,100%{box-shadow:0 0 0 4px rgba(74,222,128,.16)}
  50%{box-shadow:0 0 0 8px rgba(74,222,128,.05)}
}
.statusline .mono{color:var(--gold-soft);font-size:12.5px}

.pill-link{
  display:inline-flex;
  align-items:center;
  padding:8px 18px;
  border-radius:var(--pill);
  border:1px solid rgba(168,85,247,.5);
  background:rgba(168,85,247,.14);
  color:var(--neon-hi);
  font-size:13px;
  font-weight:600;
  white-space:nowrap;
  transition:background .2s ease,border-color .2s ease,color .2s ease;
}
.pill-link:hover{
  background:rgba(168,85,247,.28);
  border-color:var(--line-strong);
  color:#E7D6FF;
}

.nav-toggle{
  display:none;
  align-items:center;
  gap:8px;
  padding:8px 16px;
  border-radius:var(--pill);
  border:1px solid var(--line);
  background:var(--indigo);
  font-size:13px;
  font-weight:600;
  cursor:pointer;
}
.nav-toggle__bars{
  position:relative;
  display:inline-block;
  width:16px;
  height:2px;
  border-radius:2px;
  background:currentColor;
}
.nav-toggle__bars::before,
.nav-toggle__bars::after{
  content:"";
  position:absolute;
  left:0;
  width:16px;
  height:2px;
  border-radius:2px;
  background:currentColor;
}
.nav-toggle__bars::before{top:-5px}
.nav-toggle__bars::after{top:5px}
.nav-toggle[aria-expanded="true"]{
  border-color:var(--line-strong);
  color:var(--neon-hi);
}

/* 栏目层 */
.site-nav{
  border-top:1px solid var(--line);
  background:linear-gradient(180deg,rgba(28,26,69,.55),rgba(18,18,46,.35));
}
.site-nav__list{
  display:flex;
  align-items:center;
  gap:6px;
  padding:8px 0;
  overflow-x:auto;
  scrollbar-width:none;
}
.site-nav__list::-webkit-scrollbar{display:none}
.site-nav__list li{flex:0 0 auto}
.site-nav__list a{
  display:block;
  padding:8px 18px;
  border-radius:var(--pill);
  font-size:14px;
  font-weight:600;
  color:var(--muted);
  white-space:nowrap;
  transition:background .18s ease,color .18s ease,box-shadow .18s ease;
}
.site-nav__list a:hover{
  color:var(--text);
  background:rgba(168,85,247,.14);
}
.site-nav__list a[aria-current="page"]{
  background:linear-gradient(120deg,var(--neon),#7C3AED);
  color:#fff;
  box-shadow:0 0 0 1px rgba(192,132,252,.6),0 8px 20px -10px rgba(168,85,247,.95);
}

/* 滚动进度（由 JS 注入 .scroll-progress） */
.scroll-progress{
  position:absolute;
  left:0;
  right:0;
  bottom:-1px;
  height:2px;
  background:linear-gradient(90deg,var(--cyan),var(--neon),var(--gold));
  transform:scaleX(0);
  transform-origin:0 50%;
  transition:transform .1s linear;
}

/* ============================================================
   页脚
   ============================================================ */
.site-footer{
  margin-top:clamp(44px,7vw,96px);
  border-top:1px solid var(--line);
  background:linear-gradient(180deg,rgba(28,26,69,.5),rgba(7,7,26,.98));
}

.footer-grid{
  display:grid;
  grid-template-columns:1.5fr 1fr 1fr 1.7fr;
  gap:clamp(20px,3vw,40px);
  padding-block:clamp(36px,5vw,60px) clamp(22px,3vw,34px);
}

.footer-brand__name{
  margin:0 0 8px;
  font-size:19px;
  font-weight:900;
  letter-spacing:-.02em;
}
.footer-brand__tag{
  margin:0;
  max-width:20em;
  font-size:14px;
  line-height:1.7;
  color:var(--muted);
}

.footer-col__title{
  margin:0 0 14px;
  font-size:12.5px;
  font-weight:600;
  letter-spacing:.12em;
  text-transform:uppercase;
  color:var(--cyan);
}
.footer-links{display:flex;flex-direction:column;gap:9px}
.footer-links a{
  color:var(--muted);
  font-size:14.5px;
  transition:color .18s ease,padding-left .18s ease;
}
.footer-links a:hover{color:var(--neon-hi);padding-left:4px}

.footer-contact{
  display:grid;
  grid-template-columns:auto minmax(0,1fr);
  gap:8px 14px;
  font-size:14px;
}
.footer-contact dt{
  color:var(--muted);
  font-size:12.5px;
  letter-spacing:.08em;
  padding-top:2px;
}
.footer-contact dd{color:var(--text);line-height:1.6}
.footer-contact .mono{color:var(--gold-soft);font-size:13.5px}
.footer-col--contact .footer-legal__note{margin-top:14px}

.footer-legal{
  display:flex;
  flex-wrap:wrap;
  align-items:center;
  gap:10px 20px;
  padding-block:18px clamp(22px,3vw,30px);
  font-size:13px;
  color:var(--muted);
}
.footer-legal p{margin:0;max-width:none}
.footer-legal__copy{color:var(--muted)}
.footer-legal__icp{
  font-family:var(--font-mono);
  font-variant-numeric:tabular-nums;
  color:var(--gold-soft);
  padding:4px 12px;
  border-radius:var(--pill);
  border:1px solid rgba(255,209,102,.28);
  background:rgba(255,180,84,.08);
}
.footer-legal__note{
  font-size:12.5px;
  line-height:1.6;
  color:var(--muted);
  max-width:26em;
}

/* ============================================================
   进场元素
   ============================================================ */
.js [data-reveal]{
  opacity:0;
  transform:translateY(14px);
  transition:opacity .5s ease,transform .5s ease;
}
.js [data-reveal].is-visible{
  opacity:1;
  transform:none;
}

/* ============================================================
   响应式
   ============================================================ */
@media (max-width:1000px){
  .footer-grid{grid-template-columns:1fr 1fr}
  .footer-brand{grid-column:1 / -1}
  .footer-col--contact{grid-column:1 / -1}
}

@media (max-width:900px){
  :root{--header-offset:96px}
  .brand__tag{display:none}
}

@media (max-width:860px){
  .nav-toggle{display:inline-flex}
  .statusline__label{display:none}
  .site-nav{display:none}
  .site-nav[data-open]{
    display:block;
    border-top:1px solid var(--line-strong);
    box-shadow:0 24px 40px -28px rgba(0,0,0,.95);
  }
  .site-nav[data-open] .site-nav__list{
    padding:12px 0 16px;
    animation:tab-in .18s ease both;
  }
  .brandbar__inner{flex-wrap:nowrap}
}

@media (max-width:620px){
  body{font-size:16px}
  .brand__name{font-size:15.5px}
  .brand__mark{width:36px;height:36px;border-radius:12px;font-size:17px}
  .footer-grid{grid-template-columns:1fr}
  .pill-link{padding:7px 14px;font-size:12.5px}
  .statusline{display:none}
  .footer-legal{font-size:12.5px}
}

@media (max-width:360px){
  .brand__name{white-space:normal}
}

/* ============================================================
   可访问性：减弱动效
   ============================================================ */
@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;transform:none}
  .scroll-progress{transition:none}
  .dot{animation:none}
}