/* =============================================================
   土建监理视频知识库 - 前台样式
   ============================================================= */

:root{
  --bg:#f4f6fb;
  --card:#ffffff;
  --text:#1f2937;
  --text-2:#475569;
  --muted:#7b8794;
  --primary:#2563eb;
  --primary-dark:#1d4ed8;
  --primary-soft:#eaf0fe;
  --border:#e4e8f0;
  --border-2:#d3dae7;
  --ok:#16a34a;
  --warn:#d97706;
  --danger:#dc2626;
  --radius:12px;
  --radius-sm:8px;
  --shadow:0 2px 10px rgba(15,23,42,.05);
  --shadow-lg:0 10px 30px rgba(15,23,42,.10);
  --maxw:1200px;
}

*{box-sizing:border-box}
html{-webkit-text-size-adjust:100%}
body{
  margin:0;
  font-family:-apple-system,BlinkMacSystemFont,"Segoe UI","PingFang SC","Hiragino Sans GB","Microsoft YaHei",sans-serif;
  background:var(--bg);
  color:var(--text);
  font-size:15px;
  line-height:1.65;
}
img{max-width:100%;display:block}
a{color:var(--primary);text-decoration:none}
a:hover{color:var(--primary-dark)}
h1,h2,h3,h4{margin:0 0 .5em;line-height:1.35;font-weight:700}
p{margin:0 0 1em}
code{background:#eef2f9;padding:1px 6px;border-radius:5px;font-size:.9em;font-family:ui-monospace,Consolas,monospace}
.mono{font-family:ui-monospace,Consolas,monospace}
.muted{color:var(--muted)}
.small{font-size:13px}
.ta-r{text-align:right}
.spacer{flex:1}

.wrap{max-width:var(--maxw);margin:0 auto;padding:0 18px}

/* ---------- 顶栏 ---------- */
.site-header{
  background:#fff;
  border-bottom:1px solid var(--border);
  position:sticky;top:0;z-index:50;
  box-shadow:0 1px 3px rgba(15,23,42,.04);
}
.header-inner{display:flex;align-items:center;gap:18px;height:64px}
.brand{display:flex;align-items:center;gap:10px;color:var(--text);flex-shrink:0}
.brand:hover{color:var(--text)}
.brand-mark{
  width:36px;height:36px;border-radius:9px;flex-shrink:0;
  background:linear-gradient(135deg,#2563eb,#4f46e5);
  color:#fff;font-weight:700;font-size:17px;
  display:flex;align-items:center;justify-content:center;
}
.brand-text{display:flex;flex-direction:column;line-height:1.25}
.brand-text strong{font-size:16px}
.brand-text small{font-size:11px;color:var(--muted);font-weight:400}

.main-nav{display:flex;align-items:center;gap:4px;margin-left:auto}
.main-nav a{padding:7px 12px;border-radius:8px;color:var(--text-2);font-size:14px}
.main-nav a:hover{background:var(--primary-soft);color:var(--primary)}
.main-nav a.active{background:var(--primary);color:#fff}
.main-nav .nav-key{
  font-size:12px;color:var(--muted);background:#f1f4fa;
  padding:4px 10px;border-radius:999px;max-width:130px;overflow:hidden;text-overflow:ellipsis;white-space:nowrap;
}
.main-nav .nav-exit{font-size:13px;color:var(--muted)}

.nav-toggle{display:none;background:none;border:0;font-size:22px;color:var(--text);cursor:pointer;padding:4px 8px}

/* ---------- Flash ---------- */
.flash-wrap{padding-top:14px}
.flash{padding:11px 15px;border-radius:var(--radius-sm);font-size:14px;margin-bottom:10px}
.flash-success{background:#f0fdf4;color:#15803d;border:1px solid #bbf7d0}
.flash-error{background:#fef2f2;color:#b91c1c;border:1px solid #fecaca}
.flash-info{background:#eff6ff;color:#1d4ed8;border:1px solid #bfdbfe}

/* ---------- 通用 ---------- */
.btn{
  display:inline-flex;align-items:center;justify-content:center;gap:6px;
  padding:9px 18px;border-radius:9px;border:1px solid var(--border-2);
  background:#fff;color:var(--text);font-size:14px;cursor:pointer;
  text-decoration:none;line-height:1.2;transition:.15s;
}
.btn:hover{border-color:var(--primary);color:var(--primary)}
.btn-primary{background:var(--primary);border-color:var(--primary);color:#fff}
.btn-primary:hover{background:var(--primary-dark);border-color:var(--primary-dark);color:#fff}
.btn-ghost{background:#f8fafc}
.btn-ghost.on{background:#fff7e6;border-color:#f6c453;color:#b45309}
.btn-mini{padding:5px 11px;font-size:12.5px;border-radius:7px}
.btn-block{width:100%;margin-bottom:8px}
.btn-danger{color:var(--danger);border-color:#f3c6c6}
.btn-danger:hover{background:#fef2f2;border-color:var(--danger);color:var(--danger)}
.copy-fail{color:var(--danger) !important;border-color:#f3c6c6 !important;background:#fef2f2 !important}

.chip{
  display:inline-block;padding:3px 10px;border-radius:999px;background:#eef2f9;
  color:var(--text-2);font-size:12.5px;margin:0 6px 6px 0;
}
.chip-tag{background:#eaf0fe;color:var(--primary)}
.chip-lg{padding:6px 14px;font-size:13.5px}
.chip-warn{background:#fff4e5;color:#b45309}

.empty{
  padding:44px 20px;text-align:center;color:var(--muted);background:#fff;
  border:1px dashed var(--border-2);border-radius:var(--radius);font-size:14px;
}

/* ---------- 首页 Hero（仅搜索框） ---------- */
.hero{
  background:linear-gradient(135deg,#1e3a8a 0%,#2563eb 55%,#4f46e5 100%);
  color:#fff;padding:32px 0 30px;margin-bottom:26px;
}
.hero-search{display:flex;gap:10px;max-width:660px}
.hero-search input{
  flex:1;padding:14px 18px;border:0;border-radius:11px;font-size:15px;outline:none;
  box-shadow:0 6px 20px rgba(0,0,0,.14);
}
.hero-search button{
  padding:14px 30px;border:0;border-radius:11px;background:#0f172a;color:#fff;
  font-size:15px;cursor:pointer;font-weight:600;
}
.hero-search button:hover{background:#020617}

/* ---------- 首页布局 ---------- */
.home-grid{display:grid;grid-template-columns:minmax(0,1fr) 330px;gap:22px;padding-bottom:40px}
.home-grid.single{grid-template-columns:minmax(0,1fr)}
.block{background:#fff;border-radius:var(--radius);box-shadow:var(--shadow);padding:20px;margin-bottom:22px}
.block-head{display:flex;align-items:center;justify-content:space-between;margin-bottom:14px}
.block-head h2{font-size:17px;margin:0}
.block-head .more{font-size:13px}
.side-col .block{margin-bottom:20px}

.cat-grid{display:grid;grid-template-columns:repeat(auto-fill,minmax(178px,1fr));gap:12px}
.cat-card{
  display:flex;flex-direction:column;gap:2px;padding:15px;border:1px solid var(--border);
  border-radius:var(--radius-sm);color:var(--text);background:#fcfdff;transition:.15s;
}
.cat-card:hover{border-color:var(--primary);box-shadow:0 4px 14px rgba(37,99,235,.10);transform:translateY(-1px);color:var(--text)}
.cat-icon{font-size:20px}
.cat-name{font-weight:600;font-size:14.5px}
.cat-count{font-size:12px;color:var(--primary)}
.cat-sub{font-size:11.5px;color:var(--muted);line-height:1.4;margin-top:3px}

.tag-cloud{display:flex;flex-wrap:wrap;gap:8px}
.tag-cloud .tag{
  padding:5px 12px;border-radius:999px;background:#f1f5fb;color:var(--text-2);font-size:13px;
}
.tag-cloud .tag i{font-style:normal;color:var(--muted);margin-left:5px;font-size:11.5px}
.tag-cloud .tag:hover{background:var(--primary-soft);color:var(--primary)}
.tag-cloud .tag.on{background:var(--primary);color:#fff}
.tag-cloud.small .tag{font-size:12.5px;padding:4px 10px}

.mini-list{list-style:none;margin:0;padding:0}
.mini-list li{display:flex;align-items:center;gap:10px;padding:8px 0;border-bottom:1px dashed var(--border);font-size:13.5px}
.mini-list li:last-child{border-bottom:0}
.mini-list a{flex:1;overflow:hidden;text-overflow:ellipsis;white-space:nowrap;color:var(--text-2)}
.mini-list a:hover{color:var(--primary)}

/* ---------- 视频卡片 ---------- */
.video-list{display:grid;grid-template-columns:repeat(auto-fill,minmax(250px,1fr));gap:14px}
.video-card{
  display:flex;gap:12px;padding:12px;border:1px solid var(--border);border-radius:var(--radius-sm);
  background:#fff;color:var(--text);transition:.15s;
}
.video-card:hover{border-color:var(--primary);box-shadow:0 4px 16px rgba(37,99,235,.10);color:var(--text)}
.vc-cover{
  width:104px;height:66px;border-radius:7px;overflow:hidden;flex-shrink:0;position:relative;background:#e8edf7;
}
.vc-cover img{width:100%;height:100%;object-fit:cover}
.vc-cover-empty{display:flex;align-items:center;justify-content:center}
.vc-cover-glyph{color:#93a3bb;font-size:20px}
.vc-duration{
  position:absolute;right:4px;bottom:4px;background:rgba(15,23,42,.75);color:#fff;
  font-size:11px;padding:1px 6px;border-radius:4px;
}
.vc-body{display:flex;flex-direction:column;gap:5px;min-width:0;flex:1}
.vc-title{font-weight:600;font-size:14.5px;line-height:1.45;display:-webkit-box;-webkit-line-clamp:2;-webkit-box-orient:vertical;overflow:hidden}
.vc-desc{font-size:12.5px;color:var(--muted);display:-webkit-box;-webkit-line-clamp:2;-webkit-box-orient:vertical;overflow:hidden}
.vc-meta{display:flex;align-items:center;flex-wrap:wrap;gap:6px;font-size:11.5px;color:var(--muted);margin-top:auto}
.vc-meta .chip{margin:0;padding:1px 8px;font-size:11px}

/* ---------- 分页 ---------- */
.pager{display:flex;gap:6px;justify-content:center;flex-wrap:wrap;margin:26px 0}
.pager a,.pager span{
  min-width:34px;height:34px;padding:0 10px;display:inline-flex;align-items:center;justify-content:center;
  border-radius:8px;background:#fff;border:1px solid var(--border);font-size:13.5px;color:var(--text-2);
}
.pager a:hover{border-color:var(--primary);color:var(--primary)}
.pager .current{background:var(--primary);border-color:var(--primary);color:#fff}
.pager-gap{border:0;background:none}

/* ---------- 侧栏布局 ---------- */
.layout-side{display:grid;grid-template-columns:246px minmax(0,1fr);gap:22px;padding:24px 18px 40px;max-width:var(--maxw);margin:0 auto}
.side-nav{background:#fff;border-radius:var(--radius);box-shadow:var(--shadow);padding:16px;align-self:start;position:sticky;top:80px}
.side-nav h3{font-size:14px;color:var(--muted);margin:6px 0 10px;font-weight:600}
.side-nav h3:not(:first-child){margin-top:18px}
.cat-tree{list-style:none;margin:0;padding:0;font-size:14px}
.cat-tree li>a{display:flex;justify-content:space-between;align-items:center;gap:8px;padding:7px 10px;border-radius:7px;color:var(--text-2)}
.cat-tree li>a:hover{background:var(--primary-soft);color:var(--primary)}
.cat-tree li.active>a{background:var(--primary);color:#fff}
.cat-tree li>a i{font-style:normal;font-size:12px;color:var(--muted)}
.cat-tree li.active>a i{color:rgba(255,255,255,.8)}
.cat-tree ul{list-style:none;margin:2px 0 6px;padding:0 0 0 12px}
.cat-tree ul a{font-size:13px;color:var(--muted)}
.cat-tree ul a:hover{color:var(--primary)}

/* 移动端可折叠侧栏（桌面端默认全部展开） */
.side-nav-toggle{display:none}
.side-nav-body{display:block}

.breadcrumb{display:flex;gap:8px;flex-wrap:wrap;font-size:13px;color:var(--muted);margin-bottom:14px}
.breadcrumb a{color:var(--muted)}
.breadcrumb a:hover{color:var(--primary)}
.breadcrumb .current{color:var(--text-2)}

.page-title{font-size:22px;margin:0 0 4px}
.list-head{display:flex;align-items:flex-start;justify-content:space-between;gap:16px;flex-wrap:wrap;margin-bottom:16px}
.list-tools{display:flex;gap:4px;background:#fff;padding:3px;border-radius:9px;border:1px solid var(--border)}
.list-tools a{padding:5px 14px;border-radius:7px;font-size:13px;color:var(--text-2)}
.list-tools a.on{background:var(--primary);color:#fff}
.subcat-row{display:flex;flex-wrap:wrap;gap:8px;margin-bottom:16px}
.search-page-form{display:flex;gap:8px;margin-bottom:18px}
.search-page-form input{flex:1;padding:12px 16px;border:1px solid var(--border-2);border-radius:10px;font-size:15px;outline:none;background:#fff}
.search-page-form input:focus{border-color:var(--primary)}

/* ---------- 详情页 ---------- */
.detail-head{display:flex;justify-content:space-between;gap:18px;flex-wrap:wrap;margin-bottom:18px}
.detail-title-wrap{min-width:0}
.detail-head h1{font-size:25px;margin-bottom:10px}
.detail-chips{margin-bottom:8px}
.detail-meta{display:flex;gap:16px;flex-wrap:wrap}
.detail-actions{display:flex;gap:8px;align-items:flex-start}
.detail-grid{display:grid;grid-template-columns:minmax(0,1fr) 320px;gap:22px;padding-bottom:44px}
.detail-main{min-width:0}

.player-box{background:#0f172a;border-radius:var(--radius);overflow:hidden;margin-bottom:18px}
.player-frame{position:relative;width:100%;aspect-ratio:16/9;background:#000}
.player-frame video{width:100%;height:100%;border:0;display:block}

.panel{background:#fff;border-radius:var(--radius);box-shadow:var(--shadow);padding:20px;margin-bottom:20px}
.panel-title{font-size:16px;margin:0 0 14px;padding-bottom:10px;border-bottom:1px solid var(--border)}
.rich-text{font-size:15px;color:var(--text-2);word-break:break-word;overflow-wrap:anywhere}
.rich-text a{word-break:break-all}
.rich-text.foldable{max-height:340px;overflow:hidden;position:relative}
.rich-text.foldable.open{max-height:none}
.fold-toggle{display:none;margin-top:10px;background:none;border:0;color:var(--primary);cursor:pointer;font-size:13.5px;padding:0}
.fold-toggle.show{display:inline-block}

.content-tabs{margin-bottom:20px}
.tab-btns{display:flex;gap:6px;flex-wrap:wrap;margin-bottom:0;background:#fff;padding:8px 8px 0;border-radius:var(--radius) var(--radius) 0 0;box-shadow:var(--shadow)}
.tab-btn{
  border:0;background:transparent;padding:10px 16px;border-radius:9px 9px 0 0;cursor:pointer;
  font-size:14px;color:var(--text-2);position:relative;
}
.tab-btn:hover{background:#f4f7fd;color:var(--primary)}
.tab-btn.on{background:var(--primary-soft);color:var(--primary);font-weight:600}
.tab-btn .dot{display:inline-block;width:6px;height:6px;border-radius:50%;background:#f59e0b;margin-left:6px;vertical-align:middle}
.tab-panel{display:none;background:#fff;border-radius:0 0 var(--radius) var(--radius);box-shadow:var(--shadow);padding:18px 20px 20px}
.tab-panel.on{display:block}
.panel-bar{display:flex;justify-content:space-between;align-items:center;gap:12px;margin-bottom:12px;flex-wrap:wrap}

.attach-list{list-style:none;margin:0;padding:0}
.attach-list li{display:flex;align-items:center;gap:12px;padding:11px 0;border-bottom:1px dashed var(--border)}
.attach-list li:last-child{border-bottom:0}
.attach-type{
  flex-shrink:0;width:46px;height:26px;border-radius:6px;font-size:11.5px;
  display:flex;align-items:center;justify-content:center;color:#fff;background:#64748b;font-weight:600;
}
.attach-pdf{background:#dc2626}
.attach-docx{background:#2563eb}
.attach-xlsx{background:#16a34a}
.attach-pptx{background:#ea580c}
.attach-image{background:#7c3aed}
.attach-video{background:#0f766e}
.attach-archive{background:#a16207}
.attach-text{background:#475569}
.attach-info{flex:1;min-width:0;display:flex;flex-direction:column}
.attach-name{font-size:14px;word-break:break-all}

.rel-list{list-style:none;margin:0;padding:0}
.rel-list li{margin-bottom:10px}
.rel-list a{display:flex;gap:10px;align-items:center;color:var(--text-2)}
.rel-list a:hover{color:var(--primary)}
.rel-cover{width:74px;height:46px;border-radius:6px;overflow:hidden;flex-shrink:0;background:#e8edf7;display:flex;align-items:center;justify-content:center}
.rel-cover img{width:100%;height:100%;object-fit:cover}
.rel-glyph{color:#93a3bb;font-size:15px}
.rel-title{font-size:13.5px;line-height:1.45}

.info-list{margin:0;display:grid;grid-template-columns:auto 1fr;gap:6px 14px;font-size:13.5px}
.info-list dt{color:var(--muted)}
.info-list dd{margin:0;color:var(--text-2)}

.history-list{list-style:none;margin:0;padding:0;background:#fff;border-radius:var(--radius);box-shadow:var(--shadow);padding:6px 18px}
.history-list li{display:flex;justify-content:space-between;gap:14px;align-items:center;padding:12px 0;border-bottom:1px dashed var(--border)}
.history-list li:last-child{border-bottom:0}
.history-title{color:var(--text-2)}

/* ---------- 密钥验证页 ---------- */
.unlock-body{
  background:linear-gradient(135deg,#1e293b 0%,#1e3a8a 50%,#3730a3 100%);
  min-height:100vh;display:flex;align-items:center;justify-content:center;padding:24px 16px;
}
.unlock-card{
  width:100%;max-width:430px;background:#fff;border-radius:18px;padding:34px 30px;
  box-shadow:0 20px 50px rgba(2,6,23,.35);
}
.unlock-brand{text-align:center;margin-bottom:22px}
.unlock-brand .brand-mark{width:52px;height:52px;font-size:24px;border-radius:14px;margin:0 auto 14px}
.unlock-brand h1{font-size:20px;margin-bottom:6px}
.unlock-brand p{font-size:13.5px;margin:0}
.unlock-form label{display:block;font-size:13px;font-weight:600;color:var(--text-2);margin-bottom:7px}
.unlock-form input{
  width:100%;padding:13px 15px;border:1px solid var(--border-2);border-radius:10px;
  font-size:15px;letter-spacing:1px;margin-bottom:16px;outline:none;text-transform:uppercase;
}
.unlock-form input:focus{border-color:var(--primary);box-shadow:0 0 0 3px rgba(37,99,235,.12)}
.unlock-hint{font-size:12.5px;text-align:center;margin:16px 0 0;line-height:1.7}

/* ---------- 页脚 ---------- */
.site-footer{background:#fff;border-top:1px solid var(--border);margin-top:auto;padding:30px 0 16px}
.footer-inner{display:grid;grid-template-columns:2fr 1fr 2fr;gap:26px;padding-bottom:20px}
.footer-col strong{display:block;margin-bottom:8px}
.footer-col span{display:block;font-size:13px;color:var(--muted);margin-bottom:8px;font-weight:600}
.footer-col a{display:block;font-size:13.5px;color:var(--text-2);margin-bottom:5px}
.footer-col p{font-size:13px;margin:0}
.footer-bottom{display:flex;justify-content:space-between;border-top:1px solid var(--border);padding-top:14px;font-size:12.5px;color:var(--muted)}

/* ---------- 响应式 ---------- */
@media (max-width:980px){
  .home-grid{grid-template-columns:1fr}
  .layout-side{grid-template-columns:1fr}
  .side-nav{position:static}
  .detail-grid{grid-template-columns:1fr}
  .footer-inner{grid-template-columns:1fr 1fr}

  /* 分类侧栏：移动端折叠，选中分类后默认收起，内容直接可见 */
  .side-nav-collapsible{padding:0;overflow:hidden}
  .side-nav-toggle{
    display:flex;align-items:center;justify-content:space-between;gap:10px;
    width:100%;padding:14px 16px;border:0;background:#fff;cursor:pointer;
    font-size:14.5px;font-weight:600;color:var(--text);text-align:left;
  }
  .side-nav-toggle:active{background:#f7f9fd}
  .snt-label{overflow:hidden;text-overflow:ellipsis;white-space:nowrap}
  .snt-caret{
    flex-shrink:0;width:8px;height:8px;margin-right:4px;
    border-right:2px solid var(--muted);border-bottom:2px solid var(--muted);
    transform:rotate(45deg) translateY(-2px);transition:transform .18s;
  }
  .side-nav-collapsible.is-open .snt-caret{transform:rotate(-135deg) translateY(-2px)}
  .side-nav-body{display:none;padding:0 16px 14px;border-top:1px solid var(--border)}
  .side-nav-collapsible.is-open .side-nav-body{display:block}
  .side-nav-title{display:none}
}
@media (max-width:760px){
  .header-inner{height:auto;flex-wrap:wrap;padding:10px 0;gap:10px}
  .nav-toggle{display:block;order:2;margin-left:auto}
  .main-nav{display:none;order:4;width:100%;flex-wrap:wrap}
  .main-nav.open{display:flex}
  .hero{padding:26px 0 24px}
  .hero-search{flex-direction:column}
  .video-list{grid-template-columns:1fr}
  .cat-grid{grid-template-columns:repeat(auto-fill,minmax(140px,1fr))}
  .detail-head h1{font-size:20px}
  .footer-inner{grid-template-columns:1fr}
  .unlock-card{padding:26px 20px}
  .tab-btn{padding:9px 11px;font-size:13px}
}