header {
            text-align: center;
            margin-bottom: 30px;
            padding: 20px 0;
            border-bottom: 1px solid #eee;
        }
        
        h1 {
            color: #2c3e50;
            margin-bottom: 10px;
            font-size: 2.2rem;
        }
        
        .description {
            color: #7f8c8d;
            max-width: 600px;
            margin: 0 auto;
        }
        
        .container {
            display: flex;
            flex-direction: column;
            gap: 20px;
        }
        
        @media (min-width: 768px) {
            .container {
                flex-direction: row;
            }
        }
        
        .panel {
            flex: 1;
            background: #f8f9fa;
            border-radius: 8px;
            padding: 20px;
            box-shadow: 0 2px 10px rgba(0,0,0,0.05);
        }
        
        h2 {
            color: #3498db;
            margin-bottom: 15px;
            font-size: 1.4rem;
        }
        
        textarea {
            width: 100%;
            height: 150px;
            padding: 12px;
            border: 1px solid #ddd;
            border-radius: 4px;
            font-size: 16px;
            resize: vertical;
            margin-bottom: 15px;
        }
        
        .button-group {
            display: flex;
            gap: 10px;
            flex-wrap: wrap;
        }
        
        button {
            padding: 10px 15px;
            background-color: #3498db;
            color: white;
            border: none;
            border-radius: 4px;
            cursor: pointer;
            font-size: 16px;
            transition: background-color 0.3s;
            flex: 1;
            min-width: 120px;
        }
        
        button:hover {
            background-color: #2980b9;
        }
        
        button.copy {
            background-color: #27ae60;
        }
        
        button.copy:hover {
            background-color: #219653;
        }
        
        .result {
            margin-top: 15px;
            padding: 12px;
            background-color: #fff;
            border: 1px solid #ddd;
            border-radius: 4px;
            min-height: 50px;
            word-break: break-all;
        }
        
        footer {
            text-align: center;
            margin-top: 40px;
            padding: 20px 0;
            color: #7f8c8d;
            font-size: 0.9rem;
            border-top: 1px solid #eee;
        }
        
        .notification {
            position: fixed;
            top: 20px;
            right: 20px;
            padding: 15px 25px;
            background-color: #2ecc71;
            color: white;
            border-radius: 4px;
            box-shadow: 0 3px 10px rgba(0,0,0,0.1);
            opacity: 0;
            transition: opacity 0.3s;
            z-index: 1000;
        }
        
        .notification.show {
            opacity: 1;
        }