feat(export/dashboard): 导出增强与大屏公开化

导出-每次考试/多考试对比：
- 合格次数阈值等标记项抽为常显区块，三类成绩表共用
- 附缺考名单扩展到多考试导出（取所选考试全都没交的人）
- 块表每场固定2列（成绩+合并空位），修复漏推空串导致的整行左移/串列
- 列宽按实际内容估算，合并区空位只给最小宽度
- 合格次数始终显示实际次数(含0)，仅 ≥ 阈值标绿底
- 打印标题改为「成绩明细」，缺考名单分页单独成页
- 打印样式加 print-color-adjust:exact，绿底/红字可正常印出

数据大屏：
- ?class= 班级大屏免登录公开访问，接口侧放行并按班级裁剪后回传
- 单班大屏移除退出按钮，仅首页保留
- 修复红绿判定真bug：membersTable 误用 window.DASH(DASH为let声明取不到)
  改为 scoreGrade() 直接读自由变量，按后台合格率正确判红/黄/绿

测试/样例/文档同步更新，全量回归通过。

assets/style.css

@@ -431,7 +431,76 @@ table.grid tbody tr.new.clickable:hover td { background: #d6f2e2; }
 /* 弹窗内的表格不做吸顶：弹窗自身是滚动容器，吸顶表头会与内容错层（且贴边观感差） */
 .modal-body table.grid th { position: static; }
 .modal-body table.grid { box-shadow: inset 0 0 0 1px var(--border-2); border-radius: 8px; }
-/* 多考试对比导出：顶部工具条 */
+/* ================= 统一导出 / 打印弹窗 ================= */
+.ex-sec {
+  padding: 12px 14px; margin: 0 0 12px;
+  border: 1px solid var(--border); border-radius: 10px; background: #fbfcfe;
+}
+.ex-sec[hidden] { display: none; }
+.ex-sec-title {
+  font-size: 12px; font-weight: 700; color: var(--text-2);
+  letter-spacing: .3px; margin: 0 0 10px;
+  display: flex; align-items: center; gap: 8px;
+}
+.ex-sec-title small { font-weight: 500; color: var(--text-3, #8b93a1); }
+
+/* 导出内容：2×2 卡片单选，一眼看清四种导出各是什么 */
+.ex-types { display: grid; grid-template-columns: 1fr 1fr; gap: 10px; }
+.ex-type {
+  display: flex; align-items: flex-start; gap: 9px; padding: 10px 12px;
+  border: 1px solid var(--border); border-radius: 9px; background: #fff;
+  cursor: pointer; transition: border-color .15s, box-shadow .15s, background .15s;
+}
+.ex-type:hover { border-color: #b9c2d0; }
+.ex-type:has(input:checked) {
+  border-color: var(--primary, #2f6fed); background: #f3f7ff;
+  box-shadow: 0 0 0 1px var(--primary, #2f6fed) inset;
+}
+.ex-type input { margin-top: 3px; flex: none; }
+.ex-type-t { display: flex; flex-direction: column; gap: 3px; min-width: 0; }
+.ex-type-t b { font-size: 13px; color: var(--text); }
+.ex-type-t small { font-size: 11.5px; color: var(--text-3, #8b93a1); line-height: 1.45; }
+
+/* 字段行 */
+.ex-row { display: flex; flex-wrap: wrap; gap: 14px 18px; align-items: flex-start; }
+.ex-field {
+  display: flex; flex-direction: column; gap: 6px; min-width: 150px;
+  font-size: 12px; font-weight: 600; color: var(--text-2);
+}
+.ex-field select, .ex-field input[type=text], .ex-field input[type=number] {
+  font-size: 13px; font-weight: 400; color: var(--text);
+}
+.ex-field-tip {
+  min-width: 200px; flex: 1 1 240px; font-weight: 400;
+  display: flex; flex-direction: column; gap: 4px; justify-content: flex-end;
+}
+.ex-field-grow { flex: 1 1 240px; }
+.ex-field-grow input { width: 100%; }
+
+/* 班级 / 组别多选：竖排标签 + 列表，便于 Ctrl 多选 */
+#exClsSel, #exGrpSel {
+  width: 168px; height: 96px; padding: 4px 6px; font-size: 12px;
+  border: 1px solid var(--border); border-radius: 8px;
+  background: #fff; color: var(--text); outline: none;
+}
+#exGrpSel { width: 132px; }
+
+.ex-checks {
+  display: flex; flex-wrap: wrap; gap: 8px 20px; margin-top: 12px;
+  font-size: 12.5px; color: var(--text);
+}
+.ex-checks label { display: flex; align-items: center; gap: 6px; cursor: pointer; }
+
+/* 多考试：勾选列表 */
+.ex-pick { margin-top: 12px; }
+.ex-pick-head {
+  display: flex; align-items: center; gap: 10px; margin: 0 0 8px;
+  font-size: 12.5px; font-weight: 600; color: var(--text-2);
+}
+.ex-pick-head small { font-weight: 500; color: var(--text-3, #8b93a1); }
+.table-scroll.mid { max-height: 208px; overflow: auto; }
+
+/* 合规的旧类名保留（其它地方仍在用 .me-bar 之类的排版习惯） */
 .me-bar { display: flex; align-items: center; gap: 16px; margin: 0 0 10px; }
 .me-bar .chk { margin: 0; white-space: nowrap; }
 .modal-foot {
@@ -626,6 +695,51 @@ body.fs-on .topbar { padding-top: 8px; padding-bottom: 8px; }
 .dash-controls .inline { color: #fff; }
 .dash-controls .btn { background: rgba(255, 255, 255, .14); border-color: transparent; color: #fff; }
 .dash-controls .btn:hover { background: rgba(255, 255, 255, .24); }
+/* 单班大屏：顶栏只保留「试卷 / 自动刷新 / 全屏」，班级选择与「← 主系统」隐藏
+   （退出按钮本形态下不再渲染，这里不再靠 CSS 藏） */
+body.dash-class #classSelWrap,
+body.dash-class #linkIndex { display: none !important; }
+/* 公开（免登录）班级大屏的角标 */
+.pub-tag {
+  display: inline-block; padding: 1px 8px; border-radius: 999px; font-size: 12px;
+  background: rgba(255, 255, 255, .16); border: 1px solid rgba(255, 255, 255, .38); color: #fff;
+}
+/* 首页汇总卡（5 卡）在该形态下无意义 */
+body.dash-home #boardSummary { display: none; }
+.dash-hero .brand-cls {
+  display: inline-block; margin-left: 2px; padding: 2px 10px; border-radius: 999px;
+  background: rgba(255, 255, 255, .18); font-size: 13px; font-weight: 600;
+}
+
+/* ---------- 首页：班级入口卡片 ---------- */
+.cls-grid {
+  display: grid; grid-template-columns: repeat(auto-fill, minmax(248px, 1fr));
+  gap: 14px; margin-top: 12px;
+}
+.cls-card {
+  min-width: 0; cursor: pointer; user-select: none;
+  background: var(--panel); border: 1px solid var(--border); border-radius: var(--radius);
+  padding: 14px 16px 12px; box-shadow: var(--shadow);
+  transition: transform .18s ease, box-shadow .18s ease, border-color .18s ease;
+}
+.cls-card:hover { transform: translateY(-3px); border-color: var(--primary); box-shadow: var(--shadow-lg); }
+.cls-card:focus-visible { outline: 2px solid var(--primary); outline-offset: 2px; }
+.cls-head { display: flex; align-items: center; justify-content: space-between; gap: 8px; }
+.cls-name { font-size: 16px; font-weight: 700; overflow: hidden; text-overflow: ellipsis; white-space: nowrap; }
+.cls-go { flex: none; font-size: 12px; font-weight: 700; color: var(--primary); }
+.cls-kpis { display: grid; grid-template-columns: repeat(3, 1fr); gap: 10px 8px; margin-top: 10px; }
+.cls-kpi { display: flex; flex-direction: column; gap: 2px; min-width: 0; }
+.cls-kpi span { font-size: 11px; color: var(--text-3); }
+.cls-kpi b { font-size: 18px; font-weight: 700; font-variant-numeric: tabular-nums; }
+.cls-kpi.k-ok b { color: var(--ok); }
+.cls-kpi.k-warn b { color: var(--warn); }
+.cls-bar { height: 8px; border-radius: 999px; background: var(--border-2); overflow: hidden; margin-top: 12px; }
+.cls-bar > i { display: block; height: 100%; border-radius: 999px; transition: width .5s ease; }
+.cls-sub {
+  margin-top: 7px; font-size: 11.5px; color: var(--text-3);
+  display: flex; justify-content: space-between; gap: 8px;
+}
+@media (max-width: 860px) { .cls-grid { grid-template-columns: 1fr; } }
 
 .sec-title { margin: 22px 0 4px; font-size: 15px; font-weight: 700; display: flex; align-items: center; gap: 8px; }
 .sec-title .tag-gray { background: var(--border-2); color: var(--text-3); padding: 1px 9px; border-radius: 999px; font-size: 12px; font-weight: 600; }
@@ -692,6 +806,9 @@ body.dash.fs-on .card b { font-size: 20px; }
 body.dash.fs-on .group-compare { gap: 12px; }
 body.dash.fs-on .gpanel { padding: 12px 14px; }
 body.dash.fs-on .member-list { max-height: none; }
+body.dash.fs-on .cls-grid { grid-template-columns: repeat(auto-fill, minmax(212px, 1fr)); gap: 10px; }
+body.dash.fs-on .cls-card { padding: 10px 12px; }
+body.dash.fs-on .cls-kpi b { font-size: 15px; }
 
 
 /* ================= 随机抽取页 ================= */