*{margin:0;padding:0;box-sizing:border-box}body{margin:0;font-family:Segoe UI,Tahoma,Geneva,Verdana,sans-serif;-webkit-font-smoothing:antialiased;-moz-osx-font-smoothing:grayscale;background-color:#f5f5f5}#root{margin:0;padding:0}.qr-generator{min-height:100vh;background:linear-gradient(135deg,#667eea,#764ba2);padding:20px;font-family:Segoe UI,Tahoma,Geneva,Verdana,sans-serif}.qr-container{max-width:800px;margin:0 auto;background:#fff;border-radius:20px;box-shadow:0 20px 40px #0000001a;padding:40px;animation:fadeInUp .6s ease-out}@keyframes fadeInUp{0%{opacity:0;transform:translateY(30px)}to{opacity:1;transform:translateY(0)}}.qr-container h1{text-align:center;color:#333;margin-bottom:30px;font-size:2.5rem;font-weight:700;background:linear-gradient(135deg,#667eea,#764ba2);-webkit-background-clip:text;-webkit-text-fill-color:transparent;background-clip:text}.input-section{margin-bottom:30px}.input-group{margin-bottom:20px}.input-group label{display:block;margin-bottom:8px;font-weight:600;color:#555;font-size:.95rem}.input-group textarea{width:100%;padding:15px;border:2px solid #e1e5e9;border-radius:12px;font-size:16px;font-family:inherit;resize:vertical;transition:all .3s ease;box-sizing:border-box}.input-group textarea:focus{outline:none;border-color:#667eea;box-shadow:0 0 0 3px #667eea1a}.controls-row{display:grid;grid-template-columns:repeat(auto-fit,minmax(150px,1fr));gap:20px;margin-bottom:20px}.controls-row .input-group input{width:100%;padding:12px;border:2px solid #e1e5e9;border-radius:8px;font-size:14px;transition:all .3s ease;box-sizing:border-box}.controls-row .input-group input:focus{outline:none;border-color:#667eea;box-shadow:0 0 0 3px #667eea1a}.controls-row .input-group input[type=color]{height:45px;cursor:pointer}.button-group{display:flex;gap:15px;justify-content:center;flex-wrap:wrap}.generate-btn,.clear-btn,.download-btn{padding:15px 30px;border:none;border-radius:12px;font-size:16px;font-weight:600;cursor:pointer;transition:all .3s ease;text-transform:uppercase;letter-spacing:.5px}.generate-btn{background:linear-gradient(135deg,#667eea,#764ba2);color:#fff;box-shadow:0 4px 15px #667eea4d}.generate-btn:hover:not(:disabled){transform:translateY(-2px);box-shadow:0 6px 20px #667eea66}.generate-btn:disabled{background:#ccc;cursor:not-allowed;transform:none;box-shadow:none}.clear-btn{background:#f8f9fa;color:#6c757d;border:2px solid #e9ecef}.clear-btn:hover{background:#e9ecef;transform:translateY(-2px)}.download-btn{background:linear-gradient(135deg,#28a745,#20c997);color:#fff;box-shadow:0 4px 15px #28a7454d}.download-btn:hover{transform:translateY(-2px);box-shadow:0 6px 20px #28a74566}.qr-display{text-align:center}.qr-result{animation:fadeIn .5s ease-out}@keyframes fadeIn{0%{opacity:0}to{opacity:1}}.qr-result h3{color:#333;margin-bottom:20px;font-size:1.5rem}.qr-code-wrapper{display:inline-block;padding:20px;background:#fff;border-radius:16px;box-shadow:0 8px 25px #0000001a;margin-bottom:20px;border:1px solid #e1e5e9}.download-section{margin-top:20px}.qr-info{margin-top:15px;color:#666;font-size:14px;word-break:break-all;background:#f8f9fa;padding:15px;border-radius:8px;border-left:4px solid #667eea}.qr-info span{font-weight:600;color:#333}.json-info{margin-top:15px;padding:15px;background:linear-gradient(135deg,#e3f2fd,#f3e5f5);border-radius:8px;border-left:4px solid #2196f3}.json-info p{margin:0;color:#1565c0;font-size:14px;line-height:1.5}.csv-upload-container{background:#f8f9fa;border:2px dashed #dee2e6;border-radius:12px;padding:20px;margin:20px 0;text-align:center}.csv-upload-container h3{margin:0 0 15px;color:#495057;font-size:18px}.upload-section{margin-bottom:15px}.file-input{width:100%;padding:12px;border:2px solid #ced4da;border-radius:8px;background:#fff;font-size:14px;cursor:pointer;transition:all .3s ease}.file-input:hover{border-color:#007bff}.file-input:disabled{background:#e9ecef;cursor:not-allowed}.upload-info{margin-top:15px;padding:15px;background:#e7f3ff;border-radius:8px;text-align:left}.upload-info p{margin:0 0 10px;font-weight:600;color:#0056b3}.upload-info ul{margin:0;padding-left:20px;color:#495057}.upload-info li{margin-bottom:5px;font-size:14px}.upload-status{padding:12px;border-radius:8px;margin:10px 0;font-weight:500}.upload-status.uploading{background:#fff3cd;color:#856404;border:1px solid #ffeaa7}.upload-status.success{background:#d4edda;color:#155724;border:1px solid #c3e6cb}.upload-status.error{background:#f8d7da;color:#721c24;border:1px solid #f5c6cb}.stored-data-info{background:#e8f5e8;border:1px solid #c3e6cb;border-radius:8px;padding:15px;margin-top:15px;text-align:left}.stored-data-info h4{margin:0 0 10px;color:#155724;font-size:16px}.stored-data-info p{margin:5px 0;color:#495057;font-size:14px}.clear-button{background:#dc3545;color:#fff;border:none;padding:8px 16px;border-radius:6px;cursor:pointer;font-size:14px;margin-top:10px;transition:background-color .3s ease}.clear-button:hover{background:#c82333}.student-selector{margin:15px 0}.student-selector select{width:100%;padding:12px;border:2px solid #ced4da;border-radius:8px;background:#fff;font-size:14px;cursor:pointer}.student-selector select:focus{outline:none;border-color:#007bff;box-shadow:0 0 0 3px #007bff1a}.student-form{background:#f8f9fa;border-radius:16px;padding:25px;margin-bottom:30px;border:2px solid #e9ecef}.form-header{display:flex;justify-content:space-between;align-items:center;margin-bottom:25px;flex-wrap:wrap;gap:15px}.form-header h3{color:#495057;margin:0;font-size:1.3rem;font-weight:600}.form-buttons{display:flex;gap:10px;flex-wrap:wrap}.sample-btn,.clear-form-btn{padding:8px 16px;border:none;border-radius:8px;font-size:14px;font-weight:500;cursor:pointer;transition:all .3s ease}.sample-btn{background:linear-gradient(135deg,#28a745,#20c997);color:#fff}.sample-btn:hover{transform:translateY(-1px);box-shadow:0 4px 12px #28a7454d}.clear-form-btn{background:#6c757d;color:#fff}.clear-form-btn:hover{background:#5a6268;transform:translateY(-1px)}.form-grid{display:grid;grid-template-columns:repeat(auto-fit,minmax(250px,1fr));gap:20px;margin-bottom:25px}.form-group{display:flex;flex-direction:column}.form-group.full-width{grid-column:1 / -1}.form-group label{margin-bottom:8px;font-weight:600;color:#495057;font-size:.9rem}.form-group input{padding:12px;border:2px solid #dee2e6;border-radius:8px;font-size:14px;transition:all .3s ease;font-family:inherit}.form-group input:focus{outline:none;border-color:#667eea;box-shadow:0 0 0 3px #667eea1a}.json-preview{background:#fff;border-radius:12px;padding:20px;border:1px solid #dee2e6}.json-preview h4{margin:0 0 15px;color:#495057;font-size:1rem;font-weight:600}.json-display{background:#f8f9fa;border:1px solid #e9ecef;border-radius:8px;padding:15px;font-family:Courier New,monospace;font-size:13px;color:#495057;overflow-x:auto;white-space:pre-wrap;margin:0;max-height:200px;overflow-y:auto}.mode-selector{display:flex;justify-content:center;margin-bottom:30px;background:#f8f9fa;border-radius:12px;padding:8px;border:2px solid #e9ecef}.mode-btn{flex:1;padding:12px 20px;border:none;background:transparent;border-radius:8px;font-weight:600;cursor:pointer;transition:all .3s ease;color:#6c757d}.mode-btn.active{background:linear-gradient(135deg,#667eea,#764ba2);color:#fff;box-shadow:0 2px 8px #667eea4d}.mode-btn:not(.active):hover{background:#e9ecef;color:#495057}@media(max-width:768px){.qr-container{padding:20px;margin:10px}.qr-container h1{font-size:2rem}.controls-row{grid-template-columns:1fr}.button-group{flex-direction:column}.generate-btn,.clear-btn,.download-btn{width:100%}.form-header{flex-direction:column;align-items:stretch}.form-buttons{justify-content:center}.form-grid{grid-template-columns:1fr}.mode-selector{flex-direction:column;gap:8px}}@media(max-width:480px){.qr-generator{padding:10px}.qr-container{padding:15px}.qr-container h1{font-size:1.8rem}.student-form{padding:15px}}