:root{--ink: #1e293b;--ink-strong: #0f172a;--muted: #64748b;--faint: #94a3b8;--line: #e2e8f0;--line-strong: #cbd5e1;--bg: #f4f6f8;--card: #ffffff;--accent: #3b5bdb;--accent-strong: #2f4bc0;--accent-soft: #eef1fd;--danger: #b42318;--danger-soft: #fef3f2;--ok: #067647;--ok-soft: #ecfdf3;--radius: 10px;--shadow: 0 1px 2px rgba(15, 23, 42, .06)}*{box-sizing:border-box}html,body{margin:0;padding:0}body{font-family:-apple-system,BlinkMacSystemFont,Segoe UI,Roboto,Helvetica Neue,Arial,sans-serif;background:var(--bg);color:var(--ink);font-size:14px;line-height:1.45;-webkit-font-smoothing:antialiased}button{font:inherit;cursor:pointer}input,select,textarea{font:inherit;color:var(--ink)}.app{min-height:100vh;display:flex;flex-direction:column}.topbar{background:var(--card);border-bottom:1px solid var(--line);padding:10px 20px 0;position:sticky;top:0;z-index:30}.topbar-row{display:flex;align-items:center;gap:14px;flex-wrap:wrap}.brand{display:flex;align-items:center;gap:9px;font-weight:700;font-size:15px;color:var(--ink-strong);letter-spacing:-.01em}.brand-mark{width:26px;height:26px;border-radius:7px;background:var(--accent);color:#fff;display:grid;place-items:center;font-size:13px;font-weight:700}.brand-sub{font-size:11.5px;color:var(--muted);font-weight:500}.class-tabs{display:flex;align-items:center;gap:6px;flex-wrap:wrap;flex:1;min-width:0}.class-tab{display:inline-flex;align-items:center;gap:6px;border:1px solid var(--line);background:var(--card);border-radius:999px;padding:5px 12px;font-size:13px;font-weight:600;color:var(--muted)}.class-tab.active{background:var(--accent-soft);border-color:var(--accent);color:var(--accent-strong)}.class-tab:hover:not(.active){border-color:var(--line-strong);color:var(--ink)}.class-tab .tab-actions{display:inline-flex;gap:2px}.icon-btn{border:none;background:transparent;border-radius:6px;color:inherit;padding:2px 4px;font-size:12px;line-height:1;display:inline-grid;place-items:center}.icon-btn:hover{background:#0f172a14}.icon-btn.danger:hover{background:var(--danger-soft);color:var(--danger)}.new-class-btn{margin-left:auto}.topbar-tools{display:flex;align-items:center;gap:8px;margin-left:auto}.main{flex:1;display:grid;grid-template-columns:280px minmax(0,1fr) 300px;gap:16px;padding:16px 20px 32px;align-items:start;width:100%;max-width:1560px;margin:0 auto}.col{display:flex;flex-direction:column;gap:16px;min-width:0}.card{background:var(--card);border:1px solid var(--line);border-radius:var(--radius);box-shadow:var(--shadow)}.card-head{display:flex;align-items:center;justify-content:space-between;gap:8px;padding:12px 14px 10px}.card-title{font-size:13px;font-weight:700;color:var(--ink-strong);text-transform:uppercase;letter-spacing:.05em}.card-body{padding:0 14px 14px}.hint{color:var(--muted);font-size:12px}.btn{border:1px solid var(--line-strong);background:var(--card);color:var(--ink);border-radius:8px;padding:7px 12px;font-size:13px;font-weight:600;display:inline-flex;align-items:center;gap:6px;white-space:nowrap}.btn:hover{background:#f8fafc}.btn:disabled{opacity:.5;cursor:not-allowed}.btn.primary{background:var(--accent);border-color:var(--accent);color:#fff}.btn.primary:hover{background:var(--accent-strong)}.btn.danger{color:var(--danger);border-color:#fecdca}.btn.danger:hover{background:var(--danger-soft)}.btn.small{padding:4px 9px;font-size:12px;border-radius:7px}.btn.block{width:100%;justify-content:center}.unseated-zone{min-height:44px;border:1px dashed var(--line-strong);border-radius:8px;padding:8px;display:flex;flex-wrap:wrap;gap:6px;background:#fafbfd}.unseated-zone.droppable{border-color:var(--accent);background:var(--accent-soft)}.student-chip{border:1px solid var(--line-strong);background:var(--card);border-radius:7px;padding:4px 9px;font-size:12.5px;font-weight:600;cursor:grab;color:var(--ink)}.student-chip:active{cursor:grabbing}.student-chip.absent{text-decoration:line-through;color:var(--danger);border-color:#fecdca}.roster-list{display:flex;flex-direction:column;gap:4px;max-height:320px;overflow:auto;margin-top:10px}.roster-row{display:flex;align-items:center;gap:6px;padding:4px 6px;border-radius:7px;border:1px solid transparent}.roster-row:hover{background:#f8fafc}.roster-row .name{flex:1;font-weight:600;font-size:13px;min-width:0;overflow:hidden;text-overflow:ellipsis;white-space:nowrap}.roster-row .meta{font-size:11px;color:var(--faint)}.roster-row.unseated{border-color:var(--line);background:#fffdf5;cursor:grab}.roster-row.found{border-color:var(--accent);background:var(--accent-soft)}.roster-add{display:flex;gap:6px;margin-top:10px}.text-input{border:1px solid var(--line-strong);border-radius:8px;padding:7px 10px;font-size:13px;width:100%;background:var(--card)}.text-input:focus{outline:2px solid var(--accent-soft);border-color:var(--accent)}.toolbar{display:flex;align-items:center;gap:10px;flex-wrap:wrap;padding:10px 12px;background:var(--card);border:1px solid var(--line);border-radius:var(--radius);box-shadow:var(--shadow)}.segment{display:inline-flex;border:1px solid var(--line-strong);border-radius:8px;overflow:hidden}.segment button{border:none;background:var(--card);padding:7px 12px;font-size:13px;font-weight:600;color:var(--muted);border-right:1px solid var(--line)}.segment button:last-child{border-right:none}.segment button.on{background:var(--ink-strong);color:#fff}.find-wrap{position:relative;margin-left:auto}.find-wrap input{width:190px}.conflict-banner{border:1px solid #fedf89;background:#fffaeb;color:#7a2e0e;border-radius:var(--radius);padding:10px 14px;font-size:13px}.conflict-banner strong{color:var(--danger)}.conflict-banner ul{margin:6px 0 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.marker-x{display:inline}.marker-x{display:none;color:var(--danger);margin-left:5px;cursor:pointer}.seat-area{display:flex;flex-direction:column;gap:10px;align-items:center}.seat-row-el{display:flex;gap:12px;justify-content:center}.seat-box{display:flex;gap:4px;padding:4px;border-radius:9px}.seat-box.pod{flex-direction:column;gap:4px}.seat-box.pod .seat-box-row{display:flex;gap:4px}.seat{width:84px;min-height:66px;border:1.5px solid var(--line-strong);border-radius:9px;background:#fff;position:relative;display:flex;align-items:center;justify-content:center;text-align:center;padding:4px 6px;font-size:12.5px;font-weight:600;line-height:1.25;cursor:pointer;transition:border-color .12s,box-shadow .12s}.seat.empty{border-style:dashed;color:var(--faint);font-weight:500;font-size:11.5px}.seat:hover{border-color:var(--accent)}.seat.drag-over{border-color:var(--accent);background:var(--accent-soft);border-style:dashed}.seat.drag-over.swappable:after{content:"对调";position:absolute;top:-9px;right:-6px;background:var(--accent);color:#fff;font-size:9.5px;font-weight:700;padding:1px 6px;border-radius:999px;letter-spacing:.04em}.seat.occupied{cursor:grab}.seat.absent{border-color:#fda29b;background:var(--danger-soft);color:var(--danger)}.seat.absent .seat-name{text-decoration:line-through}.seat .att-badge{position:absolute;top:3px;right:4px;font-size:9px;font-weight:800;color:var(--danger);background:#fff;border:1px solid #fda29b;border-radius:4px;padding:0 3px}.seat.found{outline:3px solid var(--accent);outline-offset:1px;box-shadow:0 0 0 6px var(--accent-soft);z-index:4}.seat.filled-c1{border-top:4px solid #4f7cf7}.seat.filled-c2{border-top:4px solid 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4px;font-size:12.5px;font-weight:600;text-align:center}.choice.on{border-color:var(--accent);background:var(--accent-soft);color:var(--accent-strong)}.marker-add{display:flex;gap:6px;flex-wrap:wrap;margin-top:10px}.rule-card{border:1px solid var(--line);border-radius:8px;padding:8px 10px;margin-bottom:8px;background:#fbfcfe}.rule-card .rule-top{display:flex;align-items:center;gap:8px}.rule-card select{border:1px solid var(--line-strong);border-radius:6px;font-size:12px;padding:3px 5px;background:var(--card);font-weight:600}.rule-chips{display:flex;flex-wrap:wrap;gap:5px;margin-top:7px}.rule-chip{display:inline-flex;align-items:center;gap:4px;background:var(--accent-soft);color:var(--accent-strong);border-radius:999px;padding:2px 9px;font-size:12px;font-weight:600}.rule-chip button{border:none;background:transparent;color:inherit;font-size:12px;padding:0;line-height:1}.add-rule-student{margin-top:7px;width:100%}.picker-result{margin-top:12px;border:1px solid var(--line);border-radius:9px;padding:14px;text-align:center;background:var(--accent-soft)}.picker-result .picked-name{font-size:22px;font-weight:800;color:var(--ink-strong)}.picker-result .picked-sub{color:var(--muted);font-size:12px;margin-top:2px}.check-row{display:flex;align-items:center;gap:8px;font-size:13px;margin-bottom:6px}.export-grid{display:grid;grid-template-columns:1fr 1fr;gap:8px}.export-grid .btn{justify-content:center}.span-2{grid-column:span 2}.modal-overlay{position:fixed;top:0;right:0;bottom:0;left:0;background:#0f172a73;display:grid;place-items:center;z-index:100;padding:20px}.modal{background:var(--card);border-radius:14px;box-shadow:0 24px 64px #0f172a4d;width:100%;max-width:680px;max-height:88vh;overflow:auto;display:flex;flex-direction:column}.modal.narrow{max-width:460px}.modal-head{padding:16px 20px 0}.modal-title{font-size:17px;font-weight:800;color:var(--ink-strong)}.modal-sub{color:var(--muted);font-size:13px;margin-top:3px}.modal-body{padding:14px 20px;flex:1}.modal-foot{padding:12px 20px 16px;display:flex;gap:8px;justify-content:flex-end;border-top:1px solid var(--line)}.paste-area{width:100%;min-height:150px;border:1px solid var(--line-strong);border-radius:9px;padding:10px;font-size:13px;resize:vertical}.import-tabs{display:flex;gap:6px;margin-bottom:12px}.preview-table{width:100%;border-collapse:collapse;font-size:12.5px}.preview-table th,.preview-table td{border:1px solid var(--line);padding:5px 8px;text-align:left}.preview-table th{background:#f8fafc;font-size:11px;text-transform:uppercase;letter-spacing:.04em}.role-select{font-size:11px;border:1px solid var(--line-strong);border-radius:5px;padding:2px 3px;max-width:100%}.issue-card{border:1px solid var(--line);border-left:3px solid #f79009;border-radius:8px;padding:7px 10px;margin-bottom:6px;font-size:12.5px;display:flex;align-items:center;gap:8px;flex-wrap:wrap}.issue-card.blank{border-left-color:var(--faint)}.issue-card.duplicate{border-left-color:#f79009}.issue-card.multi{border-left-color:var(--accent)}.issue-card label{margin-left:auto;display:inline-flex;gap:4px;align-items:center;font-size:11.5px;font-weight:600;color:var(--muted);white-space:nowrap}.restore-summary{border:1px solid var(--line);border-radius:9px;overflow:hidden}.restore-summary table{width:100%;border-collapse:collapse;font-size:13px}.restore-summary td,.restore-summary th{padding:7px 10px;border-bottom:1px solid var(--line);text-align:left}.warn-note{background:var(--danger-soft);color:var(--danger);border-radius:8px;padding:8px 11px;font-size:12.5px;font-weight:600;margin-top:10px}.ok-note{background:var(--ok-soft);color:var(--ok);border-radius:8px;padding:8px 11px;font-size:12.5px;font-weight:600;margin-top:10px}.toast{position:fixed;bottom:22px;left:50%;transform:translate(-50%);background:var(--ink-strong);color:#fff;border-radius:999px;padding:9px 18px;font-size:13px;font-weight:600;box-shadow:0 10px 30px #0f172a59;z-index:200}.print-root{display:none}@media print{@page{size:letter landscape;margin:12mm}body{background:#fff}.app,.toast,.modal-overlay{display:none!important}.print-root{display:block!important}.print-title{display:flex;justify-content:space-between;align-items:baseline;border-bottom:2px solid #111827;padding-bottom:6px;margin-bottom:14px}.print-title h1{font-size:18px;margin:0}.print-title .date{font-size:12px;color:#4b5563}.print-front{text-align:center;font-size:11px;letter-spacing:.14em;text-transform:uppercase;color:#4b5563;border-bottom:2px solid #111827;padding-bottom:4px;margin-bottom:12px;font-weight:700}.print-front.bottom{border-bottom:none;border-top:2px solid #111827;padding:4px 0 0;margin:12px 0 0}.print-grid{display:flex;flex-direction:column;gap:8px;align-items:center}.print-row{display:flex;gap:10px}.print-box{display:flex;gap:3px}.print-box.pod{flex-direction:column;gap:3px}.print-seat{width:92px;height:54px;border:1px solid #9ca3af;border-radius:6px;display:flex;align-items:center;justify-content:center;text-align:center;font-size:11px;font-weight:600;padding:2px}.print-seat.absent{border-style:dashed;color:#b42318;text-decoration:line-through}.print-seat .lbl{position:absolute;font-size:7px;color:#6b7280}.print-extras{margin-top:16px;font-size:11px;color:#374151;display:flex;gap:28px}.print-extras h3{font-size:11px;text-transform:uppercase;letter-spacing:.08em;margin:0 0 4px}.print-extras ul{margin:0;padding-left:14px}}@media (max-width: 1240px){.main{grid-template-columns:260px minmax(0,1fr)}.main .col.right{grid-column:1 / -1;display:grid;grid-template-columns:repeat(auto-fit,minmax(280px,1fr));align-items:start}}@media (max-width: 860px){.main{grid-template-columns:1fr;padding:12px 12px 28px}.main .col.right{grid-template-columns:1fr}.topbar{padding:10px 12px 0}.seat{width:72px;min-height:58px;font-size:11.5px}}