/* ============================================================
   dnssec.css — DNSSEC部署与验证 子课题分页专用样式
   合并自 threat-intel.css（td-* hero 段）与 topic-attck.css（分页/内容段）
   与 ../../style.css 全局变量（--primary / --text / --border 等）完全兼容
   ============================================================ */

/* ===== 子课题详情页（topic-*.html）公共 hero 样式 ===== */
.td-hero {
    position: relative;
    padding: 150px 0 56px;
    background: linear-gradient(180deg, #f0f5ff 0%, #ffffff 100%);
    overflow: hidden;
}
.td-hero::before {
    content: '';
    position: absolute;
    top: -120px; right: -120px;
    width: 420px; height: 420px;
    background: radial-gradient(circle, rgba(26,110,255,0.08) 0%, transparent 70%);
    border-radius: 50%;
}
.td-hero::after {
    content: '';
    position: absolute;
    bottom: -160px; left: -100px;
    width: 380px; height: 380px;
    background: radial-gradient(circle, rgba(0,198,255,0.07) 0%, transparent 70%);
    border-radius: 50%;
}
.td-breadcrumb {
    display: flex;
    align-items: center;
    gap: 8px;
    font-size: 13px;
    color: var(--text-light);
    margin-bottom: 22px;
    flex-wrap: wrap;
}
.td-breadcrumb a { color: var(--primary); text-decoration: none; font-weight: 500; }
.td-breadcrumb a:hover { text-decoration: underline; }
.td-breadcrumb svg { width: 13px; height: 13px; flex-shrink: 0; }
.td-num {
    display: inline-flex;
    align-items: baseline;
    gap: 10px;
    font-size: 15px;
    font-weight: 900;
    color: var(--primary);
    letter-spacing: 2px;
    margin-bottom: 12px;
}
.td-num em {
    font-style: normal;
    font-size: 42px;
    line-height: 1;
    background: var(--primary-gradient);
    -webkit-background-clip: text;
    -webkit-text-fill-color: transparent;
    background-clip: text;
}
.td-hero h1 {
    font-size: clamp(26px, 4vw, 40px);
    font-weight: 900;
    color: var(--text);
    letter-spacing: -0.5px;
    margin-bottom: 16px;
    line-height: 1.25;
}
.td-lead {
    font-size: 15px;
    color: var(--text-secondary);
    line-height: 1.85;
    max-width: 780px;
    margin-bottom: 22px;
}
.td-chips { display: flex; flex-wrap: wrap; gap: 8px; margin-bottom: 24px; }
.td-chip {
    font-size: 12px;
    font-weight: 600;
    color: var(--primary);
    background: var(--primary-light);
    border: 1px solid rgba(26, 110, 255, 0.15);
    padding: 5px 14px;
    border-radius: 100px;
}
.td-chip.status-active { background: #e6f7ed; color: #2ea043; border-color: #b7ebc6; }
.td-chip.status-planned { background: #f0f0f5; color: var(--text-light); border-color: var(--border); }
.td-meta-bar {
    display: flex;
    flex-wrap: wrap;
    gap: 0;
    background: white;
    border: 1px solid var(--border);
    border-radius: var(--radius);
    overflow: hidden;
    box-shadow: 0 4px 16px rgba(15, 23, 42, 0.04);
}
.td-meta-item {
    flex: 1;
    min-width: 200px;
    padding: 16px 22px;
    border-right: 1px solid var(--border);
}
.td-meta-item:last-child { border-right: none; }
.td-meta-item em {
    display: block;
    font-style: normal;
    font-size: 11px;
    font-weight: 700;
    color: var(--text-light);
    letter-spacing: 1px;
    margin-bottom: 6px;
}
.td-meta-item span { font-size: 14px; font-weight: 600; color: var(--text); line-height: 1.5; }

/* ===== 分页器（子课题分页） ===== */
.apt-pager{display:flex;align-items:center;justify-content:space-between;gap:16px;flex-wrap:wrap;margin-bottom:36px;padding:18px 22px;background:#fff;border:1px solid var(--border);border-radius:14px}
.apt-pager.bottom{margin:40px 0 0}
.pager-btn{display:inline-flex;align-items:center;gap:8px;padding:11px 20px;border-radius:10px;font-size:14px;font-weight:600;text-decoration:none;border:1.5px solid var(--border);color:var(--text-secondary);background:#fff;transition:var(--transition)}
.pager-btn:hover{border-color:var(--primary);color:var(--primary);transform:translateY(-2px);box-shadow:var(--shadow)}
.pager-btn.primary{background:var(--primary-gradient);color:#fff;border-color:transparent;box-shadow:0 4px 14px rgba(26,110,255,.28)}
.pager-btn.primary:hover{transform:translateY(-2px);box-shadow:0 8px 22px rgba(26,110,255,.36);color:#fff}
.pager-steps{display:flex;align-items:center;gap:6px;flex-wrap:wrap}
.p-label{font-size:12px;color:var(--text-light);font-weight:600;margin-right:4px}
.pager-steps a{width:34px;height:34px;border-radius:50%;display:flex;align-items:center;justify-content:center;font-size:13px;font-weight:700;color:var(--text-secondary);background:#fff;border:1.5px solid var(--border);text-decoration:none;transition:var(--transition)}
.pager-steps a:hover{border-color:var(--primary);color:var(--primary)}
.pager-steps a.active{background:var(--primary-gradient);color:#fff;border-color:transparent;box-shadow:0 4px 12px rgba(26,110,255,.3)}

/* ===== 主体布局：侧边目录 + 内容 ===== */
.content-grid{display:grid;grid-template-columns:250px minmax(0,1fr);gap:36px;align-items:start}
.content-sidebar{position:sticky;top:96px}
.sidebar-nav{background:#fff;border:1px solid var(--border);border-radius:14px;padding:20px}
.sidebar-nav h4{font-size:13px;font-weight:800;color:var(--text);margin-bottom:12px;padding-bottom:10px;border-bottom:1px solid var(--border);letter-spacing:.5px}
.sidebar-nav>ul{list-style:none;padding:0;margin:0}
.sidebar-nav>ul>li{margin-bottom:2px}
.sidebar-nav>ul a{display:block;padding:8px 12px;border-radius:8px;font-size:13px;color:var(--text-secondary);text-decoration:none;line-height:1.5;transition:var(--transition);border-left:2px solid transparent}
.sidebar-nav>ul a:hover{background:var(--primary-light);color:var(--primary)}
.sidebar-nav>ul a.active{background:var(--primary-light);color:var(--primary);font-weight:700;border-left-color:var(--primary)}
.mini-pager{margin-top:16px;padding-top:14px;border-top:1px dashed var(--border);display:flex;flex-direction:column;gap:6px}
.mini-pager a{display:flex;align-items:center;gap:8px;padding:9px 12px;border-radius:8px;font-size:12px;font-weight:600;color:var(--text-secondary);text-decoration:none;border:1px solid var(--border);transition:var(--transition)}
.mini-pager a:hover{border-color:var(--primary);color:var(--primary)}
.mini-pager a.active{background:var(--primary-gradient);color:#fff;border-color:transparent}
.content-main{min-width:0}

/* ===== 内容区块 ===== */
.content-section{background:#fff;border:1px solid var(--border);border-radius:16px;padding:36px 40px;margin-bottom:28px;scroll-margin-top:96px}
.content-section h2{display:flex;align-items:center;gap:10px;font-size:22px;font-weight:900;color:var(--text);margin:0 0 20px;padding-bottom:14px;border-bottom:2px solid var(--primary-light);letter-spacing:.3px}
.content-section h2::before{content:'';width:5px;height:22px;background:var(--primary-gradient);border-radius:3px;flex-shrink:0}
.content-section h3{font-size:17px;font-weight:800;color:var(--text);margin:28px 0 12px;padding-left:12px;border-left:3px solid var(--primary);line-height:1.5}
.content-section h4{font-size:15px;font-weight:700;color:var(--text);margin:18px 0 10px}
.content-section p{font-size:14.5px;color:var(--text-secondary);line-height:1.95;margin-bottom:14px}
.content-section p strong,.content-section li strong{color:var(--text);font-weight:700}
.content-section ul,.content-section ol{padding-left:22px;margin-bottom:14px}
.content-section li{font-size:14px;color:var(--text-secondary);line-height:1.9;margin-bottom:8px}
.content-section a{color:var(--primary)}
.src-note{font-size:12px !important;color:var(--text-light) !important;font-style:italic;margin-top:10px !important;margin-bottom:0 !important}

/* ===== 表格 ===== */
.table-wrap{overflow-x:auto;margin:16px 0;border:1px solid var(--border);border-radius:12px;-webkit-overflow-scrolling:touch}
.data-table{width:100%;border-collapse:collapse;font-size:13px;min-width:560px}
.data-table th{background:var(--primary-light);color:var(--text);font-weight:700;text-align:left;padding:12px 14px;white-space:nowrap;border-bottom:2px solid rgba(26,110,255,.15)}
.data-table td{padding:11px 14px;border-bottom:1px solid var(--border);color:var(--text-secondary);line-height:1.7;vertical-align:top}
.data-table tr:last-child td{border-bottom:none}
.data-table tr:hover td{background:rgba(26,110,255,.025)}
.data-table td strong{color:var(--text)}
.t-id{font-family:ui-monospace,'SF Mono',Consolas,monospace;font-size:12px;font-weight:700;color:var(--primary);background:var(--primary-light);padding:2px 8px;border-radius:6px;white-space:nowrap}

/* ===== 关键数字卡 ===== */
.kv-grid{display:grid;grid-template-columns:repeat(4,1fr);gap:16px;margin:20px 0}
.kv-card{background:linear-gradient(135deg,var(--primary-light) 0%,rgba(26,110,255,.02) 100%);border:1px solid rgba(26,110,255,.12);border-radius:14px;padding:20px;transition:var(--transition)}
.kv-card:hover{border-color:rgba(26,110,255,.3);box-shadow:var(--shadow-hover);transform:translateY(-3px)}
.kv-num{font-size:30px;font-weight:900;color:var(--primary);line-height:1;font-variant-numeric:tabular-nums}
.kv-label{font-size:13px;font-weight:700;color:var(--text);margin-top:8px}
.kv-desc{font-size:12px;color:var(--text-secondary);line-height:1.7;margin-top:6px}

/* ===== 图表框 ===== */
.figure-box{background:linear-gradient(180deg,#fbfcff 0%,#ffffff 100%);border:1px solid var(--border);border-radius:14px;padding:22px;margin:22px 0;overflow:hidden}
.figure-title{display:flex;align-items:center;gap:8px;font-size:15px;font-weight:800;color:var(--text);margin-bottom:4px}
.figure-title::before{content:'';width:8px;height:8px;background:var(--primary-gradient);border-radius:2px;transform:rotate(45deg);flex-shrink:0}
.figure-sub{font-size:12px;color:var(--text-light);margin-bottom:14px}
.figure-box canvas{width:100%;display:block;max-width:100%}
.figure-src{font-size:11.5px;color:var(--text-light);margin-top:12px;padding-top:10px;border-top:1px dashed var(--border);line-height:1.7}
.chart-legend{display:flex;flex-wrap:wrap;gap:8px 20px;margin-top:12px;justify-content:center;row-gap:8px}
.chart-legend .lg-item{display:flex;align-items:center;gap:6px;font-size:12px;color:var(--text-secondary);font-weight:500}
.chart-legend .lg-dot{width:10px;height:10px;border-radius:3px;flex-shrink:0}

/* ===== 提示框 ===== */
.info-box{background:var(--primary-light);border-left:4px solid var(--primary);border-radius:0 12px 12px 0;padding:16px 20px;margin:18px 0}
.info-box p{font-size:13.5px;color:var(--text-secondary);line-height:1.85;margin:0}
.info-box p strong{color:var(--text)}
.warn-box{background:#fff8f0;border-left:4px solid #f57c00;border-radius:0 12px 12px 0;padding:16px 20px;margin:18px 0}
.warn-box p{font-size:13.5px;color:#7a4a12;line-height:1.85;margin:0}
.warn-box p strong{color:#5c3609}

/* ===== 代码块（dig / delv 示例 / 配置片段） ===== */
.code-block{background:#0f172a;border-radius:12px;padding:20px 22px;margin:16px 0;overflow-x:auto;-webkit-overflow-scrolling:touch}
.code-block pre{margin:0;font-family:ui-monospace,'SF Mono',Consolas,monospace;font-size:12.5px;line-height:1.75;color:#dbeafe;white-space:pre}
.code-cap{font-size:12px;font-weight:700;color:var(--text-light);margin:14px 0 6px}

/* ===== 参考来源 ===== */
.ref-list{display:flex;flex-direction:column;gap:10px}
.ref-item{display:flex;gap:14px;background:#fff;border:1px solid var(--border);border-radius:10px;padding:14px 18px;transition:var(--transition)}
.ref-item:hover{border-color:rgba(26,110,255,.2);box-shadow:var(--shadow)}
.ref-num{font-size:12px;font-weight:800;color:var(--primary);background:var(--primary-light);padding:2px 8px;border-radius:6px;flex-shrink:0;height:fit-content;font-family:ui-monospace,Consolas,monospace}
.ref-item p{font-size:12.5px;color:var(--text-secondary);line-height:1.75;margin:0;word-break:break-all}
.ref-item a{color:var(--primary);text-decoration:none;word-break:break-all}
.ref-item a:hover{text-decoration:underline}

/* ===== 响应式 ===== */
@media (max-width:1024px){
  .content-grid{grid-template-columns:1fr}
  .content-sidebar{position:static}
  .sidebar-nav>ul{display:flex;flex-wrap:wrap;gap:4px}
  .sidebar-nav>ul a{border-left:none;border:1px solid var(--border);border-radius:100px;padding:6px 14px;font-size:12px}
  .sidebar-nav>ul a.active{border-color:var(--primary)}
  .mini-pager{flex-direction:row;flex-wrap:wrap}
  .kv-grid{grid-template-columns:repeat(2,1fr)}
}
@media (max-width:768px){
  .kv-grid{grid-template-columns:1fr 1fr}
  .kv-num{font-size:24px}
  .content-section{padding:24px 18px}
  .content-section h2{font-size:19px}
  .apt-pager{flex-direction:column;align-items:stretch}
  .pager-btn{justify-content:center}
  .pager-steps{justify-content:center}
  .figure-box{padding:16px 10px}
  .figure-title{font-size:14px}
  .td-hero { padding: 120px 0 40px; }
  .td-meta-item { min-width: 100%; border-right: none; border-bottom: 1px solid var(--border); }
  .td-meta-item:last-child { border-bottom: none; }
}
@media (max-width:420px){
  .kv-grid{grid-template-columns:1fr}
}

/* ===== 第8页：案例卡片 / 风险矩阵 / 等级标签 ===== */
.case-grid{display:grid;grid-template-columns:repeat(2,1fr);gap:18px;margin:18px 0}
.case-card{background:var(--card,#fff);border:1px solid var(--border,#e3e8f0);border-radius:14px;padding:18px;position:relative;transition:transform .25s ease,box-shadow .25s ease}
.case-card:hover{transform:translateY(-3px);box-shadow:0 10px 28px rgba(26,110,255,.12)}
.case-head{display:flex;align-items:center;justify-content:space-between;gap:10px;margin-bottom:8px}
.case-tag{display:inline-block;font-size:12px;font-weight:700;padding:3px 10px;border-radius:20px;color:#fff}
.case-tag.warn{background:#f57c00}
.case-tag.danger{background:#ef4444}
.case-tag.info{background:#1a6eff}
.case-date{font-size:12px;color:var(--muted,#7a8aa0);font-weight:600}
.case-card h3{font-size:17px;margin:2px 0 8px;color:var(--heading,#14213d)}
.case-card p{font-size:13.5px;line-height:1.7;color:var(--text,#33415c);margin:0 0 8px}
.case-card code{font-family:ui-monospace,Menlo,Consolas,monospace;background:rgba(26,110,255,.08);padding:1px 6px;border-radius:5px;font-size:12.5px;color:#1a6eff}
.case-lesson{margin-bottom:0!important;padding:8px 10px;border-left:3px solid #2ea043;background:rgba(46,160,67,.07);border-radius:0 8px 8px 0;font-size:13px!important}
.case-lesson strong{color:#1f7a32}

.risk-matrix .lvl{display:inline-block;min-width:34px;text-align:center;font-size:12px;font-weight:700;border-radius:6px;padding:2px 8px}
.lvl.hi{background:#fde2e2;color:#c62828}
.lvl.mid{background:#fff2d6;color:#a65e00}
.lvl.lo{background:#e2f5e9;color:#1f7a32}
.risk-matrix .badge{display:inline-block;min-width:34px;text-align:center;font-size:12px;font-weight:800;border-radius:6px;padding:3px 10px;color:#fff}
.badge.hi{background:#ef4444}
.badge.mid{background:#f57c00}
.badge.lo{background:#2ea043}

@media (max-width:768px){
  .case-grid{grid-template-columns:1fr}
}
/* ============================================================
   顶部导航 + 页脚 移动端适配
   （自 threat-intel.css 提取，补齐各专题分页缺失部分）
   ============================================================ */

/* ---------- ≤1024px：页脚由4列降为2列 ---------- */
@media (max-width: 1024px) {
    .footer-grid { grid-template-columns: 1fr 1fr; }
}

/* ---------- ≤768px：导航折叠为汉堡菜单 + 页脚单列 ---------- */
@media (max-width: 768px) {
    /* —— 顶部导航 —— */
    .nav-links {
        display: none;
        position: absolute;
        top: 72px;
        left: 0;
        right: 0;
        background: #fff;
        flex-direction: column;
        padding: 16px 24px;
        box-shadow: 0 8px 24px rgba(0, 0, 0, 0.08);
        gap: 4px;
        border-bottom: 1px solid var(--border);
        z-index: 999;
    }
    .nav-links.active { display: flex; }
    .mobile-toggle { display: flex; }

    /* —— 页脚 —— */
    .footer-grid { grid-template-columns: 1fr; gap: 24px; }

    /* —— 通用区块 / 卡片（部分专题页有此结构，一并补齐） —— */
    .section { padding: 48px 0; }
    .subtopic-card.expanded { grid-column: auto; }
}