:root{--primary: #4F46E5;--primary-hover: #4338CA;--bg-color: #F8FAFC;--card-bg: rgba(255, 255, 255, .9);--text-main: #0F172A;--text-muted: #64748B;--border: #E2E8F0;--success: #10B981;--warning: #F59E0B;--danger: #EF4444;--shadow-sm: 0 1px 2px 0 rgba(0, 0, 0, .05);--shadow-md: 0 4px 6px -1px rgba(0, 0, 0, .1), 0 2px 4px -1px rgba(0, 0, 0, .06);--shadow-lg: 0 10px 15px -3px rgba(0, 0, 0, .1), 0 4px 6px -2px rgba(0, 0, 0, .05);--glass-border: rgba(255, 255, 255, .5)}body,html{margin:0;padding:0;font-family:Inter,system-ui,sans-serif;background:linear-gradient(135deg,#f8fafc,#e2e8f0);color:var(--text-main);min-height:100vh}*{box-sizing:border-box}.app-container{display:flex;min-height:100vh}.sidebar{width:250px;background:#ffffffb3;-webkit-backdrop-filter:blur(10px);backdrop-filter:blur(10px);border-right:1px solid var(--glass-border);padding:2rem 1rem;display:flex;flex-direction:column;gap:1rem}.sidebar h2{font-size:1.25rem;font-weight:700;color:var(--primary);margin-bottom:1rem;padding:0 .5rem}.class-item{padding:.75rem 1rem;border-radius:.75rem;cursor:pointer;transition:all .2s ease;font-weight:500;display:flex;align-items:center;justify-content:space-between;border:1px solid transparent}.class-item:hover{background:#4f46e50d;color:var(--primary);transform:translate(4px)}.class-item.active{background:var(--primary);color:#fff;box-shadow:var(--shadow-md)}.class-item-edit{background:transparent;border:none;border-bottom:1px solid var(--primary);color:inherit;font-family:inherit;font-size:inherit;font-weight:inherit;width:100%;outline:none}.main-content{flex:1;padding:2rem;overflow-y:auto}.header-area{display:flex;justify-content:space-between;align-items:center;margin-bottom:2rem}.header-area h1{font-size:2rem;font-weight:700;margin:0;background:linear-gradient(90deg,var(--primary),#8B5CF6);-webkit-background-clip:text;-webkit-text-fill-color:transparent}.card{background:var(--card-bg);-webkit-backdrop-filter:blur(12px);backdrop-filter:blur(12px);border-radius:1rem;border:1px solid var(--glass-border);box-shadow:var(--shadow-sm);padding:1.5rem;margin-bottom:1.5rem;transition:transform .2s,box-shadow .2s}.card:hover{transform:translateY(-2px);box-shadow:var(--shadow-md)}.form-group{margin-bottom:1.5rem}.form-group label{display:block;font-size:.875rem;font-weight:600;margin-bottom:.5rem;color:var(--text-muted)}.form-control{width:100%;padding:.75rem 1rem;border-radius:.5rem;border:1px solid var(--border);background:#fff;font-family:inherit;font-size:1rem;transition:border-color .2s,box-shadow .2s}.form-control:focus{outline:none;border-color:var(--primary);box-shadow:0 0 0 3px #4f46e51a}textarea.form-control{resize:vertical;min-height:100px}.row{display:flex;gap:1.5rem;flex-wrap:wrap}.col{flex:1;min-width:280px}.btn{display:inline-flex;align-items:center;justify-content:center;gap:.5rem;padding:.75rem 1.5rem;border-radius:.5rem;font-weight:600;font-family:inherit;font-size:.875rem;cursor:pointer;transition:all .2s;border:none}.btn-primary{background:var(--primary);color:#fff;box-shadow:0 4px 6px -1px #4f46e566}.btn-primary:hover{background:var(--primary-hover);transform:translateY(-1px);box-shadow:0 6px 8px -1px #4f46e580}.btn-secondary{background:#fff;color:var(--text-main);border:1px solid var(--border)}.btn-secondary:hover{background:var(--bg-color)}table{width:100%;border-collapse:separate;border-spacing:0}th,td{padding:1rem;text-align:left;border-bottom:1px solid var(--border)}th{font-weight:600;color:var(--text-muted);font-size:.875rem;text-transform:uppercase;letter-spacing:.05em;background:#f8fafc80}tbody tr{transition:background-color .2s}tbody tr:hover{background-color:#f8fafccc}.tag{display:inline-flex;padding:.25rem .75rem;border-radius:9999px;font-size:.75rem;font-weight:600}.tag-excellent{background:#10b9811a;color:var(--success)}.tag-good{background:#f59e0b1a;color:var(--warning)}.tag-needs-attention{background:#ef44441a;color:var(--danger)}.file-upload-wrapper{position:relative;overflow:hidden;display:inline-block}.file-upload-wrapper input[type=file]{position:absolute;left:0;top:0;opacity:0;width:100%;height:100%;cursor:pointer}.history-list{display:flex;flex-direction:column;gap:.5rem}.history-item{display:flex;justify-content:space-between;padding:1rem;background:#fff;border:1px solid var(--border);border-radius:.5rem;align-items:center}.icon{width:1.25rem;height:1.25rem}.animate-fade-in{animation:fadeIn .4s ease-out forwards}@keyframes fadeIn{0%{opacity:0;transform:translateY(10px)}to{opacity:1;transform:translateY(0)}}