h1 {
            text-align: center;
            color: white;
            margin-bottom: 30px;
            font-size: 2.5em;
            text-shadow: 2px 2px 4px rgba(0,0,0,0.2);
        }
        .converter-section {
            background: white;
            border-radius: 12px;
            padding: 30px;
            margin-bottom: 20px;
            box-shadow: 0 10px 30px rgba(0,0,0,0.2);
        }
        /*h2 {*/
        /*    color: #667eea;*/
        /*    margin-bottom: 20px;*/
        /*    font-size: 1.5em;*/
        /*    border-bottom: 3px solid #667eea;*/
        /*    padding-bottom: 10px;*/
        /*}*/
        .file-input-wrapper {
            position: relative;
            margin-bottom: 20px;
        }
        .file-input-label {
            display: inline-block;
            padding: 12px 30px;
            background: #667eea;
            color: white;
            border-radius: 6px;
            cursor: pointer;
            transition: background 0.3s;
            font-weight: 500;
        }
        .file-input-label:hover {
            background: #5568d3;
        }
        input[type="file"] {
            display: none;
        }
        .file-name {
            display: inline-block;
            margin-left: 15px;
            color: #666;
        }
        textarea {
            width: 100%;
            min-height: 300px;
            padding: 15px;
            border: 2px solid #e0e0e0;
            border-radius: 6px;
            font-family: 'Courier New', monospace;
            font-size: 14px;
            resize: vertical;
            margin-bottom: 15px;
        }
        textarea:focus {
            outline: none;
            border-color: #667eea;
        }
        .button-group {
            display: flex;
            gap: 10px;
            flex-wrap: wrap;
        }
        button {
            padding: 12px 25px;
            background: #667eea;
            color: white;
            border: none;
            border-radius: 6px;
            cursor: pointer;
            font-size: 16px;
            font-weight: 500;
            transition: all 0.3s;
        }
        button:hover {
            background: #5568d3;
            transform: translateY(-2px);
            box-shadow: 0 4px 8px rgba(0,0,0,0.2);
        }
        button:active {
            transform: translateY(0);
        }
        button.secondary {
            background: #764ba2;
        }
        button.secondary:hover {
            background: #653a8a;
        }
        .preview {
            background: #f8f9fa;
            border: 2px solid #e0e0e0;
            border-radius: 6px;
            padding: 15px;
            margin-top: 15px;
            overflow-x: auto;
        }
        table {
            width: 100%;
            border-collapse: collapse;
            background: white;
        }
        th, td {
            border: 1px solid #ddd;
            padding: 10px;
            text-align: left;
        }

        th {
            background: #667eea;
            color: white;
            font-weight: 600;
        }

        tr:nth-child(even) {
            background: #f8f9fa;
        }

        .info {
            background: #e3f2fd;
            border-left: 4px solid #2196f3;
            padding: 12px;
            margin-bottom: 15px;
            border-radius: 4px;
            font-size: 14px;
            color: #1565c0;
        }

        .success {
            background: #e8f5e9;
            border-left: 4px solid #4caf50;
            padding: 12px;
            margin-top: 15px;
            border-radius: 4px;
            color: #2e7d32;
        }