*,*:before,*:after{box-sizing:border-box;margin:0;padding:0}:root{--bg: #f1f5f9;--surface: #ffffff;--surface-2: #f8fafc;--border: #e2e8f0;--border-focus: #6366f1;--text: #0f172a;--text-muted: #64748b;--text-subtle: #94a3b8;--primary: #6366f1;--primary-dark: #4f46e5;--primary-soft: #eef2ff;--present: #16a34a;--present-bg: #f0fdf4;--present-border: #bbf7d0;--absent: #dc2626;--absent-bg: #fef2f2;--absent-border: #fecaca;--warn-bg: #fffbeb;--warn-border: #fde68a;--warn-text: #92400e;--radius: 12px;--radius-sm: 8px;--radius-xs: 6px;--shadow-sm: 0 1px 3px rgba(0,0,0,.06), 0 1px 2px rgba(0,0,0,.04);--shadow: 0 4px 6px -1px rgba(0,0,0,.07), 0 2px 4px -2px rgba(0,0,0,.05);--shadow-md: 0 10px 15px -3px rgba(0,0,0,.08), 0 4px 6px -4px rgba(0,0,0,.05)}body{font-family:Inter,system-ui,-apple-system,sans-serif;font-size:14px;line-height:1.5;color:var(--text);background:var(--bg);min-height:100vh;padding:24px 16px 64px}.app{max-width:1200px;margin:0 auto;display:flex;flex-direction:column;gap:16px}.card{background:var(--surface);border:1px solid var(--border);border-radius:var(--radius);box-shadow:var(--shadow-sm)}.header{display:flex;align-items:center;justify-content:space-between;gap:16px;flex-wrap:wrap;padding-bottom:8px}.header-brand{display:flex;align-items:center;gap:14px}.brand-logo{width:44px;height:44px;border-radius:var(--radius-sm);background:var(--primary);color:#fff;display:flex;align-items:center;justify-content:center;flex-shrink:0;box-shadow:0 4px 12px #6366f159}.brand-name{font-size:20px;font-weight:700;letter-spacing:-.3px;color:var(--text)}.brand-pill{display:inline-block;background:var(--primary);color:#fff;font-size:11px;font-weight:700;padding:2px 8px;border-radius:20px;letter-spacing:.5px;vertical-align:middle;margin-right:6px}.brand-sub{font-size:13px;color:var(--text-muted);margin-top:1px}.clock-card{background:var(--surface);border:1px solid var(--border);border-radius:var(--radius);padding:10px 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var(--border-focus);outline-offset:2px}.btn-primary{background:var(--primary);color:#fff;border-color:var(--primary-dark);box-shadow:0 1px 2px #0000001a}.btn-primary:not(:disabled):hover{background:var(--primary-dark);box-shadow:0 4px 10px #6366f159}.btn-ghost{background:var(--surface);color:var(--text);border-color:var(--border);box-shadow:var(--shadow-sm)}.btn-ghost:not(:disabled):hover{background:var(--surface-2);border-color:#c9d2e0}.register-bar{display:flex;align-items:center;justify-content:space-between;gap:12px;background:var(--surface);border:1px solid var(--border);border-radius:var(--radius);padding:12px 18px;box-shadow:var(--shadow-sm);flex-wrap:wrap}.register-bar-info{font-size:14px;color:var(--text-muted)}.register-bar-info strong{color:var(--text)}.register-bar-actions{display:flex;align-items:center;gap:8px;flex-shrink:0}.badge-readonly{display:inline-flex;align-items:center;gap:4px;background:var(--absent-bg);color:var(--absent);border:1px solid 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p{font-size:14px;color:var(--text-muted);max-width:320px}.import-panel{padding:20px;display:flex;flex-direction:column;gap:14px}.import-header{display:flex;align-items:flex-start;justify-content:space-between;gap:12px}.import-title{font-size:14px;font-weight:700;color:var(--text);margin-bottom:4px}.import-hint{font-size:12.5px;color:var(--text-muted);line-height:1.6}.import-hint code{background:var(--surface-2);border:1px solid var(--border);padding:1px 5px;border-radius:4px;font-family:JetBrains Mono,monospace;font-size:11.5px}.icon-btn{background:none;border:none;font-size:16px;color:var(--text-muted);cursor:pointer;padding:2px 6px;border-radius:var(--radius-xs);line-height:1;flex-shrink:0}.icon-btn:hover{background:var(--surface-2);color:var(--text)}.import-body{display:flex;flex-direction:column;gap:10px}#importTextarea{width:100%;min-height:120px;font-family:JetBrains Mono,monospace;font-size:13px;color:var(--text);background:var(--surface-2);border:1px solid var(--border);border-radius:var(--radius-sm);padding:10px 12px;resize:vertical;outline:none;line-height:1.6}#importTextarea:focus{border-color:var(--border-focus);box-shadow:0 0 0 3px #6366f11f}#importTextarea::placeholder{color:var(--text-subtle)}.import-upload-row{display:flex;align-items:center;gap:8px;flex-wrap:wrap}.upload-label{cursor:pointer}.import-preview{border-top:1px solid var(--border);padding-top:14px;display:flex;flex-direction:column;gap:6px;max-height:260px;overflow-y:auto}.import-preview-row{display:flex;align-items:center;gap:10px;padding:6px 10px;border-radius:var(--radius-xs);background:var(--surface-2);font-size:13px}.import-preview-row .avatar{width:28px;height:28px;font-size:11px;flex-shrink:0}.import-preview-row .student-name{font-size:13px}.import-preview-row .student-roll{font-size:11.5px}.import-preview-row.row-dupe{background:var(--absent-bg);border:1px solid var(--absent-border)}.import-dupe-tag{margin-left:auto;font-size:11px;font-weight:600;color:var(--absent);white-space:nowrap}footer{text-align:center;font-size:12.5px;color:var(--text-subtle);padding-top:8px}@media (max-width: 640px){.header{flex-direction:column;align-items:flex-start}.clock-card{width:100%}.context-fields{flex-direction:column;align-items:stretch}#classInput,#batchInput,#dateInput{width:100%}.toolbar{flex-direction:column;align-items:stretch}.add-student-form{flex-direction:column}#newStudentName,#newStudentRoll{width:100%}.register-bar{flex-direction:column;align-items:flex-start}.status-msg{margin-left:0}.student-card{gap:10px}.student-card-meta{min-width:unset;width:100%}.lec-chips{width:100%}.lec-chip{width:40px;height:40px}}@media (prefers-reduced-motion: reduce){*{transition:none!important}}