:root{--bg: #0f172a;--surface: #1e293b;--surface2: #243248;--border: #334155;--text: #e2e8f0;--muted: #94a3b8;--primary: #6366f1;--primary-h:#818cf8;--accent: #22d3ee;--success: #4ade80;--warning: #fb923c;--danger: #f87171;--radius: 8px;--sidebar-w:230px}*,*:before,*:after{box-sizing:border-box;margin:0;padding:0}body{font-family:Segoe UI,system-ui,sans-serif;background:var(--bg);color:var(--text);font-size:14px;line-height:1.5}.app-shell{display:flex;min-height:100vh}.sidebar{width:var(--sidebar-w);background:var(--surface);border-right:1px solid var(--border);display:flex;flex-direction:column;padding:20px 0;position:fixed;top:0;left:0;bottom:0}.sidebar-logo{padding:0 20px 24px;border-bottom:1px solid var(--border);margin-bottom:12px}.sidebar-logo h1{font-size:17px;font-weight:700;color:var(--primary-h);letter-spacing:.3px}.sidebar-logo span{font-size:11px;color:var(--muted)}.nav-link{display:flex;align-items:center;gap:10px;padding:10px 20px;color:var(--muted);text-decoration:none;transition:all .15s;font-weight:500;border-left:3px solid transparent}.nav-link:hover,.nav-link.active{background:#6366f11f;color:var(--primary-h);border-left:3px solid var(--primary)}.nav-icon{font-size:16px;width:18px;text-align:center}.sidebar-footer{margin-top:auto;padding:16px 20px;border-top:1px solid var(--border)}.user-badge{font-size:12px;color:var(--muted);margin-bottom:8px}.user-badge strong{color:var(--text);display:block}.main-content{margin-left:var(--sidebar-w);flex:1;padding:28px 32px;max-width:calc(100vw - var(--sidebar-w))}.page-header{display:flex;align-items:center;justify-content:space-between;margin-bottom:24px;gap:16px;flex-wrap:wrap}.page-title{font-size:22px;font-weight:700;color:var(--text)}.page-subtitle{color:var(--muted);font-size:13px;margin-top:2px}.back-link{color:var(--muted);text-decoration:none;font-size:13px}.back-link:hover{color:var(--primary-h)}.stat-grid{display:grid;grid-template-columns:repeat(auto-fit,minmax(150px,1fr));gap:16px;margin-bottom:28px}.stat-card{background:var(--surface);border:1px solid var(--border);border-radius:var(--radius);padding:20px}.stat-label{font-size:11px;color:var(--muted);text-transform:uppercase;letter-spacing:.8px}.stat-value{font-size:32px;font-weight:700;margin:4px 0 2px}.stat-sub{font-size:12px;color:var(--muted)}.card{background:var(--surface);border:1px solid var(--border);border-radius:var(--radius);padding:20px;margin-bottom:20px}.card-title{font-size:13px;font-weight:600;color:var(--muted);text-transform:uppercase;letter-spacing:.6px;margin-bottom:16px}.grid-cards{display:grid;grid-template-columns:repeat(auto-fill,minmax(280px,1fr));gap:16px}table{width:100%;border-collapse:collapse}th{text-align:left;font-size:11px;color:var(--muted);text-transform:uppercase;letter-spacing:.6px;padding:8px 12px;border-bottom:1px solid var(--border)}td{padding:10px 12px;border-bottom:1px solid rgba(51,65,85,.5);vertical-align:middle}tr:last-child td{border-bottom:none}tr:hover td{background:#ffffff05}.badge{display:inline-flex;align-items:center;gap:4px;padding:2px 8px;border-radius:999px;font-size:11px;font-weight:600}.badge-green{background:#4ade8026;color:var(--success)}.badge-blue{background:#22d3ee26;color:var(--accent)}.badge-orange{background:#fb923c26;color:var(--warning)}.badge-red{background:#f8717126;color:var(--danger)}.badge-gray{background:#94a3b81f;color:var(--muted)}.badge-indigo{background:#6366f12e;color:var(--primary-h)}.btn{display:inline-flex;align-items:center;gap:6px;padding:7px 14px;border-radius:var(--radius);font-size:13px;font-weight:500;cursor:pointer;border:none;transition:all .15s}.btn-primary{background:var(--primary);color:#fff}.btn-primary:hover{background:var(--primary-h)}.btn-ghost{background:transparent;color:var(--muted);border:1px solid var(--border)}.btn-ghost:hover{color:var(--text);border-color:var(--text)}.btn-danger{background:#f8717126;color:var(--danger);border:1px solid rgba(248,113,113,.3)}.btn-danger:hover{background:#f8717140}.btn-sm{padding:4px 10px;font-size:12px}.btn:disabled{opacity:.5;cursor:not-allowed}.form-group{margin-bottom:16px}label{display:block;font-size:12px;color:var(--muted);margin-bottom:6px;font-weight:500}input[type=text],input[type=password],input[type=email],input[type=number],select,textarea{width:100%;background:var(--bg);border:1px solid var(--border);border-radius:var(--radius);color:var(--text);padding:8px 12px;font-size:14px;outline:none;transition:border .15s;font-family:inherit}textarea{resize:vertical;min-height:90px}input:focus,select:focus,textarea:focus{border-color:var(--primary)}.login-wrap{min-height:100vh;display:flex;align-items:center;justify-content:center;background:var(--bg)}.login-box{width:380px;background:var(--surface);border:1px solid var(--border);border-radius:12px;padding:36px}.login-logo{text-align:center;margin-bottom:28px}.login-logo .icon{font-size:40px}.login-logo h2{font-size:20px;font-weight:700;margin-top:8px}.login-logo p{color:var(--muted);font-size:13px;margin-top:4px}.error-msg{background:#f871711f;border:1px solid rgba(248,113,113,.3);color:var(--danger);padding:8px 12px;border-radius:var(--radius);font-size:13px;margin-bottom:16px}.hint{color:var(--muted);font-size:12px;text-align:center;margin-top:16px}.modal-overlay{position:fixed;top:0;right:0;bottom:0;left:0;background:#0009;display:flex;align-items:center;justify-content:center;z-index:100;padding:16px}.modal{background:var(--surface);border:1px solid var(--border);border-radius:12px;padding:28px;width:480px;max-width:95vw;max-height:92vh;overflow-y:auto}.modal-title{font-size:18px;font-weight:700;margin-bottom:20px}.mono{font-family:monospace;font-size:12px}.flex-gap{display:flex;gap:8px;align-items:center}.flex-between{display:flex;gap:8px;align-items:center;justify-content:space-between}.mt-4{margin-top:16px}.mb-4{margin-bottom:16px}.empty{color:var(--muted);font-style:italic;font-size:13px;padding:16px 0}.empty-card{text-align:center;padding:48px 24px}.empty-card .ico{font-size:32px;margin-bottom:12px}.clickable{cursor:pointer}.clickable:hover{border-color:var(--primary)}.link-btn{background:none;border:none;color:var(--primary-h);cursor:pointer;font-size:inherit;padding:0}.attendance-toolbar{display:flex;align-items:center;gap:16px;flex-wrap:wrap;background:var(--surface);border:1px solid var(--border);border-radius:var(--radius);padding:16px 20px;margin-bottom:20px}.timer{font-size:26px;font-weight:700;font-variant-numeric:tabular-nums;color:var(--accent);letter-spacing:1px}.timer.idle{color:var(--muted)}.timer-label{font-size:11px;color:var(--muted);text-transform:uppercase;letter-spacing:.6px}.subgroup-block{margin-bottom:24px}.subgroup-head{display:flex;align-items:center;gap:10px;margin-bottom:12px}.subgroup-head h3{font-size:15px;font-weight:600;color:var(--text)}.student-grid{display:grid;grid-template-columns:repeat(auto-fill,minmax(260px,1fr));gap:12px}.student-tile{background:var(--surface);border:1px solid var(--border);border-radius:var(--radius);padding:12px 14px;display:flex;flex-direction:column;gap:10px;border-left:4px solid var(--border);transition:border-color .15s}.student-tile.present{border-left-color:var(--success)}.student-tile.late{border-left-color:var(--warning)}.student-tile.absent{border-left-color:var(--danger)}.student-tile.excluded{border-left-color:var(--primary)}.student-name{font-weight:600;font-size:14px}.student-meta{font-size:11px;color:var(--muted)}.status-row{display:flex;gap:6px;flex-wrap:wrap}.status-btn{flex:1;min-width:56px;text-align:center;cursor:pointer;-webkit-user-select:none;user-select:none;padding:6px 4px;border-radius:6px;font-size:12px;font-weight:600;background:var(--bg);border:1px solid var(--border);color:var(--muted);transition:all .12s}.status-btn:hover{color:var(--text);border-color:var(--muted)}.status-btn.on.present{background:#4ade802e;color:var(--success);border-color:var(--success)}.status-btn.on.late{background:#fb923c2e;color:var(--warning);border-color:var(--warning)}.status-btn.on.absent{background:#f871712e;color:var(--danger);border-color:var(--danger)}.status-btn.on.excluded{background:#6366f138;color:var(--primary-h);border-color:var(--primary)}.late-edit{display:flex;align-items:center;gap:6px;font-size:12px;color:var(--muted)}.late-edit input{width:64px;padding:3px 6px;font-size:12px}.summary-bar{display:flex;gap:10px;flex-wrap:wrap}.summary-pill{display:flex;flex-direction:column;align-items:center;min-width:70px;padding:8px 12px;border-radius:var(--radius);background:var(--bg);border:1px solid var(--border)}.summary-pill .n{font-size:20px;font-weight:700}.summary-pill .l{font-size:10px;text-transform:uppercase;letter-spacing:.5px;color:var(--muted)}