/* responsive.css — 真正的三档响应式
 * Desktop (>1024) / Tablet (641-1024) / Mobile (<=640)
 * 检查：导航/图片/弹窗/档案/文件/时间线/表单/字体/点击区域（提示词第55节）
 */
/* ========== Tablet ========== */
@media (max-width: 1024px) {
  :root { --container: 100%; --nav-h:58px; }
  body { font-size:14px; }
  .container { padding:0 20px; }
  .site-nav .inner { gap:20px; }
  .site-nav ul { gap:16px; }
  .site-nav ul li a { font-size:13px; }
  .hero { height:360px; }
  .hero h2 { font-size:32px; }
  .grid.cols-4 { grid-template-columns: repeat(2,1fr); }
  .grid.cols-3 { grid-template-columns: repeat(2,1fr); }
  .archive-shell { grid-template-columns:160px 1fr; }
  .page-head h1 { font-size:26px; }
  .section-title { font-size:20px; }
}

/* ========== Mobile ========== */
@media (max-width: 640px) {
  body { font-size:13px; }
  .container { padding:0 16px; }
  /* 导航折叠 */
  .site-nav ul { display:none; position:absolute; top:var(--nav-h); left:0; right:0; flex-direction:column; background:var(--color-surface); box-shadow:var(--shadow-card); padding:8px 0; gap:0; }
  .site-nav ul.open { display:flex; }
  .site-nav ul li a { padding:14px 24px; border-bottom:1px solid var(--color-line); }
  .site-nav .nav-toggle { display:block; margin-left:auto; }
  .site-nav .logo .en { display:none; }
  /* hero */
  .hero { height:280px; }
  .hero h2 { font-size:24px; letter-spacing:1px; }
  .hero p { font-size:14px; }
  .hero .cta { padding:10px 24px; font-size:13px; }
  /* 网格单列 */
  .grid.cols-4, .grid.cols-3, .grid.cols-2 { grid-template-columns: 1fr; }
  /* 档案竖排 */
  .archive-shell { grid-template-columns:1fr; }
  .archive-tabs { display:flex; gap:8px; overflow-x:auto; padding-bottom:8px; }
  .archive-tabs li a { border-left:none; border-bottom:3px solid transparent; padding:8px 12px; white-space:nowrap; }
  .archive-tabs li a.active { border-left:none; border-bottom-color:var(--color-accent); }
  /* 标题 */
  .page { padding:32px 0 56px; }
  .page-head h1 { font-size:22px; }
  .section-title { font-size:18px; padding-left:10px; }
  /* 列表 */
  .list-item { flex-direction:column; gap:6px; }
  .list-item .date { display:flex; align-items:baseline; gap:8px; }
  .list-item .date b { font-size:18px; }
  /* 文档 */
  .doc-paper { padding:20px; }
  .doc-paper .stamp { width:70px; height:70px; bottom:14px; right:16px; }
  /* 表格横滚 */
  table.data { font-size:12px; }
  table.data th, table.data td { padding:8px 10px; }
  /* 弹窗 */
  .modal-box { padding:20px; }
  .modal-box .actions { flex-direction:column-reverse; }
  .modal-box .actions button { width:100%; }
  /* 启动页 */
  #splash h1 { font-size:26px; letter-spacing:2px; }
  #splash .tagline { font-size:12px; }
  #splash .start-btn { padding:12px 36px; letter-spacing:4px; }
  /* 图片查看器按钮放大触区 */
  .viewer-overlay .vbar button { padding:12px 18px; font-size:14px; }
  /* 搜索 */
  .search-box { flex-direction:column; }
  .search-box button { padding:12px; }
  /* 点击区域 */
  .card .body { padding:14px; }
  .archive-entry { padding:14px; }
  /* 页脚 */
  .site-foot .inner { flex-direction:column; gap:8px; }
}

/* 大屏居中 */
@media (min-width: 1400px) {
  :root { --container: 1280px; }
}