* {
            margin: 0;
            padding: 0;
            box-sizing: border-box;
            font-family: 'Segoe UI', 'Microsoft YaHei', sans-serif;
        }
        
        body {
            background: linear-gradient(135deg, #667eea 0%, #764ba2 100%);
            min-height: 100vh;
            display: flex;
            justify-content: center;
            align-items: center;
            padding: 20px;
        }
        
        .container {
            background: white;
            border-radius: 15px;
            box-shadow: 0 10px 30px rgba(0, 0, 0, 0.2);
            padding: 30px;
            width: 100%;
            max-width: 900px;
        }
        
        .header {
            text-align: center;
            margin-bottom: 30px;
        }
        
        .header h1 {
            color: #333;
            font-size: 2.2rem;
            margin-bottom: 10px;
            display: flex;
            align-items: center;
            justify-content: center;
            gap: 10px;
        }
        
        .header p {
            color: #666;
            font-size: 1rem;
        }
        
        .main {
            display: grid;
            grid-template-columns: 1fr 1fr;
            gap: 30px;
            margin-bottom: 30px;
        }
        
        @media (max-width: 768px) {
            .main {
                grid-template-columns: 1fr;
            }
        }
        
        .input-section, .preview-section {
            padding: 20px;
            background: #f8fafc;
            border-radius: 10px;
            border: 1px solid #e2e8f0;
        }
        
        .section-title {
            color: #333;
            margin-bottom: 20px;
            padding-bottom: 10px;
            border-bottom: 2px solid #667eea;
            font-size: 1.3rem;
        }
        
        .form-group {
            margin-bottom: 20px;
        }
        
        label {
            display: block;
            margin-bottom: 8px;
            color: #475569;
            font-weight: 600;
        }
        
        textarea {
            width: 100%;
            padding: 12px;
            border: 2px solid #cbd5e1;
            border-radius: 8px;
            font-size: 16px;
            min-height: 120px;
            resize: vertical;
            transition: border-color 0.3s;
        }
        
        textarea:focus {
            outline: none;
            border-color: #667eea;
        }
        
        .settings-grid {
            display: grid;
            grid-template-columns: repeat(2, 1fr);
            gap: 20px;
            margin-bottom: 25px;
        }
        
        @media (max-width: 480px) {
            .settings-grid {
                grid-template-columns: 1fr;
            }
        }
        
        .color-options {
            display: flex;
            gap: 10px;
            margin-top: 8px;
            flex-wrap: wrap;
        }
        
        .color-option {
            width: 32px;
            height: 32px;
            border-radius: 6px;
            cursor: pointer;
            border: 2px solid transparent;
            transition: all 0.2s;
        }
        
        .color-option:hover {
            transform: scale(1.1);
        }
        
        .color-option.active {
            border-color: #333;
            box-shadow: 0 0 0 2px rgba(102, 126, 234, 0.3);
        }
        
        .range-group {
            display: flex;
            align-items: center;
            gap: 15px;
        }
        
        input[type="range"] {
            flex: 1;
            height: 6px;
            -webkit-appearance: none;
            background: #cbd5e1;
            border-radius: 3px;
        }
        
        input[type="range"]::-webkit-slider-thumb {
            -webkit-appearance: none;
            width: 20px;
            height: 20px;
            background: #667eea;
            border-radius: 50%;
            cursor: pointer;
        }
        
        .range-value {
            font-weight: bold;
            min-width: 40px;
            color: #333;
        }
        
        select {
            width: 100%;
            padding: 10px;
            border: 2px solid #cbd5e1;
            border-radius: 8px;
            font-size: 16px;
            background: white;
            cursor: pointer;
        }
        
        .preview-container {
            display: flex;
            flex-direction: column;
            align-items: center;
            justify-content: center;
            height: 360px;
            background: white;
            border-radius: 10px;
            border: 2px solid #e2e8f0;
            margin-bottom: 25px;
            position: relative;
        }
        
        #qrcode {
            display: flex;
            justify-content: center;
            align-items: center;
            width: 100%;
            height: 100%;
            padding: 10px;
        }
        
        #qrcode canvas {
            max-width: 100%;
            max-height: 100%;
            border-radius: 5px;
            box-shadow: 0 2px 10px rgba(0,0,0,0.1);
        }
        
        .buttons {
            display: flex;
            gap: 15px;
            justify-content: center;
        }
        
        .btn {
            padding: 12px 24px;
            border: none;
            border-radius: 8px;
            font-size: 16px;
            font-weight: 600;
            cursor: pointer;
            display: flex;
            align-items: center;
            gap: 8px;
            transition: all 0.3s;
        }
        
        .btn-primary {
            background: linear-gradient(90deg, #667eea 0%, #764ba2 100%);
            color: white;
        }
        
        .btn-primary:hover {
            transform: translateY(-2px);
            box-shadow: 0 5px 15px rgba(102, 126, 234, 0.4);
        }
        
        .btn-secondary {
            background: #e2e8f0;
            color: #475569;
        }
        
        .btn-secondary:hover {
            background: #cbd5e1;
        }
        
        .footer {
            text-align: center;
            color: #64748b;
            font-size: 0.9rem;
            padding-top: 20px;
            border-top: 1px solid #e2e8f0;
        }
        
        .status-message {
            margin-top: 15px;
            padding: 10px;
            border-radius: 6px;
            text-align: center;
            font-size: 0.9rem;
            display: none;
        }
        
        .status-success {
            background: #d1fae5;
            color: #065f46;
            border: 1px solid #a7f3d0;
        }
        
        .status-error {
            background: #fee2e2;
            color: #991b1b;
            border: 1px solid #fecaca;
        }
        
        .status-info {
            background: #dbeafe;
            color: #1e40af;
            border: 1px solid #bfdbfe;
        }
        
        .loading {
            color: #667eea;
            font-size: 1rem;
            display: flex;
            flex-direction: column;
            align-items: center;
            gap: 10px;
        }