/* 51吃瓜网 · 2026 全新骨架：资讯流 + 热榜侧栏 + 核验时间线 */
:root{
  color-scheme: light;
  --bg:#f6f7fb;
  --paper:#ffffff;
  --ink:#111827;
  --muted: rgba(17,24,39,.72);
  --muted2: rgba(17,24,39,.56);
  --line: rgba(17,24,39,.10);
  --shadow: 0 18px 46px rgba(17,24,39,.10);
  --r1: 22px;
  --r2: 16px;
  --wrap: 1180px;

  --hot:#ef4444;
  --amber:#f59e0b;
  --violet:#7c3aed;
  --cyan:#06b6d4;
  --green:#22c55e;
}
*{ box-sizing:border-box; }
html,body{ height:100%; }
body{
  margin:0;
  font-family: ui-sans-serif, system-ui, -apple-system, "Segoe UI", Roboto, "Helvetica Neue", Arial,
    "PingFang SC","Hiragino Sans GB","Microsoft YaHei","Noto Sans CJK SC","Noto Sans SC",sans-serif;
  color: var(--ink);
  line-height: 1.65;
  background:
    radial-gradient(980px 540px at 10% 0%, rgba(239,68,68,.10), transparent 60%),
    radial-gradient(900px 520px at 92% 10%, rgba(245,158,11,.10), transparent 55%),
    radial-gradient(820px 520px at 55% 120%, rgba(124,58,237,.08), transparent 55%),
    linear-gradient(180deg, #fff, var(--bg));
}
a{ color:inherit; text-decoration:none; }
img{ max-width:100%; display:block; }
.wrap{ width:100%; max-width: var(--wrap); margin:0 auto; padding:0 18px; }
.sr-only{
  position:absolute!important; width:1px;height:1px;
  overflow:hidden; clip: rect(1px,1px,1px,1px); white-space:nowrap;
}
.skip{
  position:absolute; left:-999px; top:10px;
  padding:10px 12px; border-radius: 12px;
  background: var(--paper); border:1px solid var(--line); box-shadow: var(--shadow);
}
.skip:focus{ left:12px; z-index: 99; }

/* 顶部：品牌 + 搜索 + 导航 */
.mast{
  position: sticky;
  top:0;
  z-index: 60;
  background: rgba(246,247,251,.82);
  backdrop-filter: blur(12px);
  border-bottom: 1px solid rgba(17,24,39,.08);
}
.mast-top{
  display:flex; align-items:center; justify-content:space-between; gap: 12px;
  padding: 14px 0 10px;
}
.brand{
  display:flex; align-items:center; gap: 12px;
  min-width: 260px;
}
.mark{
  width: 44px; height:44px; border-radius: 14px;
  display:grid; place-items:center;
  color:#fff; font-weight: 900; letter-spacing:.6px;
  background: conic-gradient(from 210deg, var(--hot), var(--amber), var(--violet), var(--hot));
  box-shadow: 0 14px 34px rgba(239,68,68,.18);
}
.brand small{ display:block; margin-top:2px; font-size:12px; color: var(--muted2); }

.search{
  display:flex; align-items:center; gap: 10px;
  min-width: 320px;
}
.search input{
  width:100%;
  padding: 10px 12px;
  border-radius: 14px;
  border:1px solid rgba(17,24,39,.12);
  background:#fff;
  outline:none;
}
.search input:focus{
  border-color: rgba(239,68,68,.40);
  box-shadow: 0 0 0 4px rgba(239,68,68,.12);
}
.search button{
  padding: 10px 12px;
  border-radius: 14px;
  border:1px solid rgba(17,24,39,.12);
  background:#fff;
  cursor:pointer;
}
.search button:hover{ background: rgba(17,24,39,.03); }

.nav{
  display:flex; flex-wrap:wrap; gap: 8px;
  padding: 0 0 12px;
}
.nav a{
  padding: 8px 12px;
  border-radius: 999px;
  border:1px solid transparent;
  background: rgba(255,255,255,.62);
  color: rgba(17,24,39,.82);
}
.nav a:hover{ background:#fff; border-color: rgba(17,24,39,.08); }
.nav a.on{
  background: linear-gradient(135deg, rgba(239,68,68,.14), rgba(245,158,11,.10));
  border-color: rgba(239,68,68,.18);
}

main{ padding: 18px 0 44px; }

/* 首页：头条带 + 三栏资讯流 */
.headline{
  border-radius: 28px;
  border:1px solid rgba(17,24,39,.10);
  background: rgba(255,255,255,.92);
  box-shadow: var(--shadow);
  overflow:hidden;
  margin: 12px 0 14px;
}
.headline-inner{
  display:grid;
  grid-template-columns: 1.2fr .8fr;
  gap: 12px;
  padding: 16px;
  align-items: stretch;
}
.htext h1{
  margin:0 0 10px;
  font-size: 34px;
  line-height:1.12;
}
.lead{
  margin:0;
  color: var(--muted);
  max-width: 68ch;
}
.actions{
  display:flex; flex-wrap:wrap; gap: 10px;
  margin-top: 14px;
}
.btn{
  display:inline-flex; align-items:center; justify-content:center;
  padding: 10px 12px;
  border-radius: 14px;
  border:1px solid rgba(17,24,39,.12);
  background:#fff;
  color: rgba(17,24,39,.84);
}
.btn:hover{ background: rgba(17,24,39,.03); }
.btn.primary{
  border-color: rgba(239,68,68,.18);
  background: linear-gradient(135deg, rgba(239,68,68,.16), rgba(245,158,11,.12));
  font-weight: 900;
}
.hmedia{
  border-radius: 22px;
  border:1px solid rgba(17,24,39,.10);
  overflow:hidden;
  background: rgba(17,24,39,.02);
}
.hmedia img{ width:100%; height:100%; min-height: 280px; object-fit: cover; }

.ticker{
  display:flex;
  gap: 10px;
  align-items:center;
  padding: 12px 16px;
  border-top: 1px solid rgba(17,24,39,.08);
  background: linear-gradient(90deg, rgba(239,68,68,.10), rgba(245,158,11,.08), rgba(255,255,255,.70));
}
.pulse{
  width: 10px; height:10px; border-radius: 999px;
  background: var(--hot);
  box-shadow: 0 0 0 4px rgba(239,68,68,.14);
}
.ticker b{ font-size: 13px; }
.ticker span{ color: var(--muted2); font-size: 12px; }

.board{
  display:grid;
  grid-template-columns: 240px 1fr 320px;
  gap: 12px;
  align-items:start;
}

/* 左侧：话题面板 */
.rail{
  border-radius: 26px;
  border:1px solid rgba(17,24,39,.10);
  background: rgba(255,255,255,.92);
  padding: 14px;
  box-shadow: 0 10px 24px rgba(17,24,39,.06);
}
.rail h2{ margin:0 0 10px; font-size: 14px; }
.chips{ display:flex; flex-wrap:wrap; gap: 8px; }
.chip{
  display:inline-flex;
  padding: 7px 10px;
  border-radius: 999px;
  border:1px solid rgba(17,24,39,.10);
  background: rgba(17,24,39,.02);
  color: rgba(17,24,39,.78);
  font-size: 12px;
}
.chip.hot{ border-color: rgba(239,68,68,.18); background: rgba(239,68,68,.08); color: rgba(185,28,28,.92); }
.chip.v{ border-color: rgba(124,58,237,.18); background: rgba(124,58,237,.08); color: rgba(124,58,237,.86); }
.chip.c{ border-color: rgba(6,182,212,.18); background: rgba(6,182,212,.08); color: rgba(8,145,178,.92); }
.chip.g{ border-color: rgba(34,197,94,.18); background: rgba(34,197,94,.10); color: rgba(22,163,74,.92); }

.rail .note{
  margin-top: 12px;
  padding: 12px;
  border-radius: 18px;
  border:1px solid rgba(17,24,39,.10);
  background: rgba(255,255,255,.86);
  color: var(--muted2);
  font-size: 12px;
}

/* 中间：主信息流 */
.stream{
  border-radius: 26px;
  border:1px solid rgba(17,24,39,.10);
  background: rgba(255,255,255,.94);
  overflow:hidden;
  box-shadow: 0 10px 24px rgba(17,24,39,.06);
}
.stream-head{
  padding: 14px 14px;
  border-bottom: 1px solid rgba(17,24,39,.08);
  display:flex; align-items:center; justify-content:space-between; gap: 10px;
}
.stream-head strong{ font-size: 14px; }
.filters{
  display:flex; flex-wrap:wrap; gap: 8px;
}
.filters a{
  padding: 7px 10px;
  border-radius: 999px;
  border:1px solid rgba(17,24,39,.10);
  background: rgba(17,24,39,.02);
  font-size: 12px;
  color: rgba(17,24,39,.74);
}
.filters a.on{
  border-color: rgba(239,68,68,.18);
  background: rgba(239,68,68,.08);
  color: rgba(185,28,28,.92);
}

.post{
  display:grid;
  grid-template-columns: 160px 1fr;
  gap: 12px;
  padding: 14px;
  border-top: 1px solid rgba(17,24,39,.08);
}
.post:first-child{ border-top:none; }
.thumb{
  border-radius: 18px;
  overflow:hidden;
  border:1px solid rgba(17,24,39,.10);
  background: rgba(17,24,39,.02);
}
.thumb img{ width:100%; height: 120px; object-fit: cover; }
.pmeta h3{ margin:0 0 6px; font-size: 15px; line-height:1.25; }
.pmeta p{ margin:0; color: var(--muted); font-size: 13px; }
.pfoot{
  margin-top: 10px;
  display:flex; flex-wrap:wrap; gap: 10px;
  color: var(--muted2);
  font-size: 12px;
}
.pill{
  display:inline-flex;
  padding: 6px 10px;
  border-radius: 999px;
  border:1px solid rgba(245,158,11,.18);
  background: rgba(245,158,11,.10);
  color: rgba(180,83,9,.92);
}
.pill.r{ border-color: rgba(239,68,68,.18); background: rgba(239,68,68,.08); color: rgba(185,28,28,.92); }
.pill.v{ border-color: rgba(124,58,237,.18); background: rgba(124,58,237,.08); color: rgba(124,58,237,.86); }

/* 右侧：热榜 + 核验卡 */
.side{
  display:grid;
  gap: 12px;
}
.card{
  border-radius: 26px;
  border:1px solid rgba(17,24,39,.10);
  background: rgba(255,255,255,.92);
  overflow:hidden;
  box-shadow: 0 10px 24px rgba(17,24,39,.06);
}
.card-head{
  padding: 14px 14px;
  border-bottom: 1px solid rgba(17,24,39,.08);
  display:flex; align-items:center; justify-content:space-between;
}
.card-head strong{ font-size: 14px; }
.mini{
  display:grid;
}
.mini a{
  display:grid;
  grid-template-columns: 26px 1fr;
  gap: 10px;
  padding: 12px 14px;
  border-top: 1px solid rgba(17,24,39,.08);
}
.mini a:first-child{ border-top:none; }
.n{
  width: 26px; height: 26px; border-radius: 10px;
  display:grid; place-items:center;
  background: rgba(239,68,68,.10);
  border:1px solid rgba(239,68,68,.18);
  font-weight: 900;
  color: rgba(185,28,28,.92);
  font-size: 12px;
}
.mini h3{ margin:0 0 4px; font-size: 13px; }
.mini p{ margin:0; color: var(--muted2); font-size: 12px; }

.verify{
  padding: 14px;
}
.verify p{ margin: 8px 0 0; color: var(--muted); font-size: 13px; }
.steps{
  margin-top: 10px;
  display:grid;
  gap: 8px;
}
.step{
  padding: 10px 10px;
  border-radius: 16px;
  border:1px solid rgba(17,24,39,.10);
  background: rgba(17,24,39,.02);
  color: rgba(17,24,39,.78);
  font-size: 12px;
}

/* 列表页：左右布局（目录 + 卡片网格） */
.layout{
  display:grid;
  grid-template-columns: 280px 1fr;
  gap: 12px;
  align-items:start;
}
.aside{
  border-radius: 26px;
  border:1px solid rgba(17,24,39,.10);
  background: rgba(255,255,255,.92);
  padding: 14px;
  box-shadow: 0 10px 24px rgba(17,24,39,.06);
}
.aside h2{ margin:0 0 10px; font-size: 14px; }
.aside a{
  display:block;
  padding: 10px 10px;
  border-radius: 14px;
  border:1px solid transparent;
  color: rgba(17,24,39,.80);
}
.aside a:hover{ background: rgba(17,24,39,.03); border-color: rgba(17,24,39,.08); }
.aside a.on{ background: rgba(239,68,68,.08); border-color: rgba(239,68,68,.18); }

.grid{
  display:grid;
  grid-template-columns: repeat(3, minmax(0,1fr));
  gap: 12px;
}
.tile{
  border-radius: 20px;
  border:1px solid rgba(17,24,39,.10);
  background: rgba(255,255,255,.92);
  overflow:hidden;
  transition: .15s ease;
}
.tile:hover{ transform: translateY(-2px); box-shadow: 0 18px 44px rgba(17,24,39,.10); }
.tile img{ width:100%; height: 150px; object-fit: cover; }
.tile .tmeta{ padding: 12px; }
.tile h3{ margin:0 0 6px; font-size: 14px; line-height:1.25; }
.tile p{ margin:0; color: var(--muted2); font-size: 12px; }

/* 内容页：时间线 + 右侧要点 */
.doc{
  display:grid;
  grid-template-columns: 1fr 340px;
  gap: 12px;
  align-items:start;
}
.paper{
  border-radius: 28px;
  border:1px solid rgba(17,24,39,.10);
  background: rgba(255,255,255,.95);
  box-shadow: var(--shadow);
  padding: 18px;
}
.crumb{
  display:flex; gap:8px; flex-wrap:wrap;
  color: var(--muted2);
  font-size: 12px;
  margin-bottom: 10px;
}
.paper h1{ margin:0 0 10px; font-size: 22px; line-height:1.25; }
.paper h2{ margin: 16px 0 8px; font-size: 16px; }
.paper p{ margin: 10px 0; color: var(--muted); }
.paper ul{ margin: 10px 0 10px 18px; color: var(--muted); }

.timeline{
  margin-top: 12px;
  border-radius: 22px;
  border:1px solid rgba(17,24,39,.10);
  background: rgba(17,24,39,.02);
  padding: 12px;
}
.titem{
  display:grid;
  grid-template-columns: 86px 1fr;
  gap: 10px;
  padding: 10px 10px;
  border-top: 1px solid rgba(17,24,39,.08);
}
.titem:first-child{ border-top:none; }
.t{ font-weight: 900; color: rgba(17,24,39,.78); font-size: 12px; }
.titem b{ display:block; font-size: 13px; }
.titem span{ display:block; margin-top:4px; color: var(--muted2); font-size: 12px; }

.sidebox{
  border-radius: 26px;
  border:1px solid rgba(17,24,39,.10);
  background: rgba(255,255,255,.92);
  padding: 14px;
  box-shadow: 0 10px 24px rgba(17,24,39,.06);
}
.sidebox h3{ margin:0 0 10px; font-size: 14px; }
.kv{
  display:grid;
  gap: 8px;
}
.kv div{
  padding: 10px 10px;
  border-radius: 16px;
  border:1px solid rgba(17,24,39,.10);
  background: rgba(17,24,39,.02);
  font-size: 12px;
  color: rgba(17,24,39,.78);
}
.kv b{ color: rgba(17,24,39,.92); }
.sidebox .img{
  margin-top: 10px;
  border-radius: 18px;
  overflow:hidden;
  border:1px solid rgba(17,24,39,.10);
  background: rgba(17,24,39,.02);
}

.footer{
  margin-top: 22px;
  border-top: 1px solid rgba(17,24,39,.08);
  background: rgba(255,255,255,.60);
}
.footrow{
  padding: 18px 0;
  display:flex;
  align-items:center;
  justify-content:space-between;
  gap: 12px;
  flex-wrap: wrap;
  color: rgba(17,24,39,.72);
}

/* 移动端底部导航 */
.bottom{
  display:none;
  position: fixed;
  left: 12px; right: 12px; bottom: 12px;
  z-index: 80;
  border-radius: 18px;
  border:1px solid rgba(17,24,39,.10);
  background: rgba(255,255,255,.92);
  box-shadow: var(--shadow);
  padding: 10px;
}
.bottom a{
  flex:1 1 0;
  display:flex;
  align-items:center;
  justify-content:center;
  padding: 10px 10px;
  border-radius: 14px;
  border:1px solid transparent;
  color: rgba(17,24,39,.76);
  font-size: 12px;
}
.bottom a.on{
  border-color: rgba(239,68,68,.18);
  background: rgba(239,68,68,.08);
  color: rgba(185,28,28,.92);
  font-weight: 900;
}

@media (max-width: 1060px){
  .board{ grid-template-columns: 1fr; }
  .side{ grid-template-columns: 1fr; }
  .rail{ order: 2; }
  .stream{ order: 1; }
  .side{ order: 3; }
}
@media (max-width: 980px){
  .headline-inner{ grid-template-columns: 1fr; }
  .hmedia img{ min-height: 220px; }
  .layout{ grid-template-columns: 1fr; }
  .grid{ grid-template-columns: repeat(2, minmax(0,1fr)); }
  .doc{ grid-template-columns: 1fr; }
}
@media (max-width: 720px){
  .search{ display:none; }
  main{ padding-bottom: 92px; }
  .bottom{ display:flex; gap: 10px; }
  .post{ grid-template-columns: 1fr; }
  .thumb img{ height: 160px; }
  .titem{ grid-template-columns: 72px 1fr; }
}
@media (max-width: 420px){
  .grid{ grid-template-columns: 1fr; }
}