/* ===== AI 导航频道 ===== */
.crumb{max-width:1200px;margin:16px auto 0;padding:0 16px;font-size:13px;color:#94a3b8}
.crumb a{color:#64748b;text-decoration:none}
.crumb a:hover{color:#2563eb}

.nav-hero{max-width:1200px;margin:16px auto;padding:34px 24px;border-radius:16px;
  background:linear-gradient(135deg,#1e3a8a 0%,#2563eb 45%,#7c3aed 100%);color:#fff;text-align:center;
  box-shadow:0 10px 30px rgba(37,99,235,.18)}
.nav-hero h1{margin:0 0 10px;font-size:28px;line-height:1.3}
.nav-hero p{margin:0 0 18px;opacity:.92;font-size:15px}
.nav-hero .stat{display:flex;justify-content:center;gap:38px;margin-bottom:20px;flex-wrap:wrap}
.nav-hero .stat div{display:flex;flex-direction:column;align-items:center}
.nav-hero .stat b{font-size:22px}
.nav-hero .stat span{font-size:12px;opacity:.85}
.nav-search{display:flex;max-width:600px;margin:0 auto;background:#fff;border-radius:12px;overflow:hidden;
  box-shadow:0 6px 18px rgba(0,0,0,.12)}
.nav-search input{flex:1;border:0;outline:0;padding:14px 18px;font-size:15px;color:#0f172a}
.nav-search button{border:0;background:#0f172a;color:#fff;padding:0 28px;font-size:15px;cursor:pointer}
.nav-search button:hover{background:#1e293b}

.nav-tabs{max-width:1200px;margin:0 auto 6px;padding:0 16px;display:flex;flex-wrap:wrap;gap:8px}
.nav-tab{display:inline-flex;align-items:center;gap:5px;padding:6px 13px;border:1px solid #e2e8f0;
  border-radius:999px;background:#fff;color:#475569;font-size:13px;text-decoration:none;white-space:nowrap;
  transition:.15s}
.nav-tab:hover{border-color:#93c5fd;color:#2563eb}
.nav-tab.on{background:#2563eb;border-color:#2563eb;color:#fff}
.nav-tab em{font-style:normal;font-size:11px;opacity:.75}
.nav-tab.more{border-style:dashed}

.nav-h2{max-width:1200px;margin:22px auto 0;padding:0 16px;font-size:19px;color:#0f172a}
.nav-h2 span{font-size:13px;color:#94a3b8;font-weight:400}

.nav-grid{max-width:1200px;margin:14px auto 0;padding:0 16px;display:grid;
  grid-template-columns:repeat(4,minmax(0,1fr));gap:12px}
.nav-card{display:flex;gap:11px;align-items:flex-start;padding:13px;border:1px solid #eef2f7;border-radius:12px;
  background:#fff;text-decoration:none;transition:.16s}
.nav-card:hover{border-color:#bfdbfe;box-shadow:0 6px 18px rgba(37,99,235,.10);transform:translateY(-2px)}
.nav-card .ic{flex:0 0 42px;width:42px;height:42px;display:flex;align-items:center;justify-content:center;
  border-radius:10px;background:#f8fafc;overflow:hidden}
.nav-card .ic img{width:30px;height:30px;object-fit:contain}
.nav-card .ic .ph{width:32px;height:32px;border-radius:8px;background:#e0e7ff;color:#4338ca;
  display:flex;align-items:center;justify-content:center;font-weight:700;font-size:15px}
.nav-card .tx{display:flex;flex-direction:column;min-width:0}
.nav-card .nm{font-size:14px;font-weight:600;color:#0f172a;line-height:1.3;
  overflow:hidden;text-overflow:ellipsis;white-space:nowrap}
.nav-card .ds{font-size:12px;color:#94a3b8;line-height:1.45;margin-top:3px;
  display:-webkit-box;-webkit-line-clamp:2;-webkit-box-orient:vertical;overflow:hidden}

.cat-list{max-width:1200px;margin:14px auto 30px;padding:0 16px;display:grid;
  grid-template-columns:repeat(4,minmax(0,1fr));gap:10px}
.cat-item{display:flex;justify-content:space-between;align-items:center;gap:8px;padding:10px 14px;
  border:1px solid #eef2f7;border-radius:10px;background:#fff;text-decoration:none;color:#334155;font-size:14px}
.cat-item:hover{border-color:#bfdbfe;color:#2563eb}
.cat-item em{font-style:normal;font-size:12px;color:#94a3b8}

.nav-empty{max-width:1200px;margin:26px auto;padding:36px;text-align:center;color:#94a3b8;
  background:#f8fafc;border-radius:12px}

.pager{max-width:1200px;margin:22px auto 34px;padding:0 16px;display:flex;align-items:center;
  justify-content:center;gap:6px;flex-wrap:wrap}
.pager a,.pager span{padding:7px 12px;border-radius:8px;border:1px solid #e2e8f0;background:#fff;
  color:#475569;text-decoration:none;font-size:13px;min-width:36px;text-align:center}
.pager a:hover{border-color:#93c5fd;color:#2563eb}
.pager .cur{background:#2563eb;border-color:#2563eb;color:#fff}
.pager .pinfo{border:0;background:transparent;color:#94a3b8;margin-left:10px}

.nav-note{width:calc(100% - 32px);max-width:1168px;margin:12px auto 0;box-sizing:border-box;
  padding:11px 16px;background:#fffbeb;border:1px solid #fde68a;border-radius:10px;
  color:#92400e;font-size:13px;line-height:1.65}
.nav-note b{color:#b45309}

@media (max-width:1000px){
  .nav-grid,.cat-list{grid-template-columns:repeat(3,minmax(0,1fr))}
}
@media (max-width:760px){
  .nav-hero{padding:24px 16px;border-radius:0}
  .nav-hero h1{font-size:21px}
  .nav-hero .stat{gap:22px}
  .nav-hero .stat b{font-size:18px}
  .nav-grid{grid-template-columns:repeat(2,minmax(0,1fr));gap:9px;padding:0 10px}
  .cat-list{grid-template-columns:repeat(2,minmax(0,1fr));padding:0 10px}
  .nav-card{padding:10px;gap:9px}
  .nav-card .ic{flex:0 0 34px;width:34px;height:34px}
  .nav-card .ic img{width:24px;height:24px}
  .nav-card .nm{font-size:13px}
  .nav-card .ds{font-size:11px}
  .nav-tabs{padding:0 10px;gap:6px}
  .nav-tab{font-size:12px;padding:5px 10px}
}
@media (max-width:380px){
  .nav-grid{grid-template-columns:minmax(0,1fr)}
}

/* 需梯子角标（海外被墙分类标注） */
.nav-card{position:relative}
.nav-card.lock0 .nm{padding-right:42px}
.nav-card .lock{position:absolute;top:6px;right:6px;padding:1px 6px;border-radius:6px;background:#f59e0b;color:#fff;font-size:10px;line-height:1.6;font-weight:600;white-space:nowrap}
@media (max-width:760px){.nav-card .lock{top:4px;right:4px;font-size:9px;padding:1px 5px}.nav-card.lock0 .nm{padding-right:36px}}

/* 分类页 hero（H1 + 分类简介） */
.nav-hero-cat{padding:22px 24px;text-align:left}
.nav-hero-cat h1{font-size:22px;margin:0}
.nav-hero-cat p{margin:8px 0 0;font-size:14px;opacity:.9}