:root {
            --primary: #2c3e50;
            --secondary: #3498db;
            --accent: #e74c3c;
            --light: #ecf0f1;
            --dark: #2c3e50;
            --success: #27ae60;
        }
        
        * {
            margin: 0;
            padding: 0;
            box-sizing: border-box;
            font-family: 'Segoe UI', Tahoma, Geneva, Verdana, sans-serif;
        }
        
        body {
            background-color: #f5f7fa;
            color: var(--dark);
            line-height: 1.6;
        }
        
        header {
            background: linear-gradient(135deg, var(--primary), var(--secondary));
            color: white;
            padding: 2rem 0;
            text-align: center;
            box-shadow: 0 4px 12px rgba(0,0,0,0.1);
        }

        .text-white {
            color: white;
        }
        
        .logo {
            font-size: 2.5rem;
            font-weight: 700;
            margin-bottom: 0.5rem;
        }
        
        .tagline {
            font-size: 1.2rem;
            opacity: 0.9;
            margin-bottom: 1.5rem;
        }
        
        .container {
            max-width: 1200px;
            margin: 0 auto;
            padding: 2rem;
        }
        
        .tools-grid {
            display: grid;
            grid-template-columns: repeat(auto-fit, minmax(300px, 1fr));
            gap: 2rem;
            margin-top: 2rem;
        }
        
        .tool-card {
            background: white;
            border-radius: 10px;
            overflow: hidden;
            box-shadow: 0 5px 15px rgba(0,0,0,0.1);
            transition: transform 0.3s ease, box-shadow 0.3s ease;
        }
        
        .tool-card:hover {
            transform: translateY(-5px);
            box-shadow: 0 10px 25px rgba(0,0,0,0.15);
        }
        
        .tool-header {
            background: var(--secondary);
            color: white;
            padding: 1.5rem;
            text-align: center;
        }
        
        .tool-body {
            padding: 1.5rem;
        }
        
        .tool-description {
            margin-bottom: 1.5rem;
            color: #555;
        }
        
        .upload-area {
            border: 2px dashed #ccc;
            border-radius: 8px;
            padding: 2rem;
            text-align: center;
            margin-bottom: 1rem;
            cursor: pointer;
            transition: all 0.3s;
        }
        
        .upload-area:hover {
            border-color: var(--secondary);
            background: rgba(52, 152, 219, 0.05);
        }
        
        .upload-area.active {
            border-color: var(--success);
            background: rgba(39, 174, 96, 0.05);
        }
        
        .file-input {
            display: none;
        }
        
        .btn {
            display: inline-block;
            background: var(--secondary);
            color: white;
            border: none;
            padding: 0.8rem 1.5rem;
            border-radius: 5px;
            cursor: pointer;
            font-size: 1rem;
            transition: all 0.3s;
            text-align: center;
            width: 100%;
        }
        
        .btn:hover {
            background: #2980b9;
            transform: translateY(-2px);
        }
        
        .btn:disabled {
            background: #95a5a6;
            cursor: not-allowed;
            transform: none;
        }
        
        .btn-accent {
            background: var(--accent);
        }
        
        .btn-accent:hover {
            background: #c0392b;
        }
        
        .file-queue {
            margin: 1rem 0;
            max-height: 200px;
            overflow-y: auto;
            border: 1px solid #eee;
            border-radius: 5px;
            padding: 0.5rem;
        }
        
        .file-item {
            display: flex;
            justify-content: space-between;
            align-items: center;
            padding: 0.5rem;
            border-bottom: 1px solid #eee;
        }
        
        .file-item:last-child {
            border-bottom: none;
        }
        
        .remove-file {
            color: var(--accent);
            cursor: pointer;
            font-weight: bold;
            padding: 0 0.5rem;
        }
        
        .progress-container {
            margin-top: 1rem;
            display: none;
        }
        
        .progress-bar {
            height: 8px;
            background: #ecf0f1;
            border-radius: 4px;
            overflow: hidden;
            margin-bottom: 0.5rem;
        }
        
        .progress {
            height: 100%;
            background: var(--success);
            width: 0%;
            transition: width 0.3s;
        }
        
        .status {
            font-size: 0.9rem;
            color: #7f8c8d;
            text-align: center;
        }
        
        .options {
            margin: 1rem 0;
        }
        
        .option-group {
            margin-bottom: 1rem;
        }
        
        .option-label {
            display: block;
            margin-bottom: 0.5rem;
            font-weight: 500;
        }
        
        .option-select, .option-input {
            width: 100%;
            padding: 0.5rem;
            border: 1px solid #ddd;
            border-radius: 4px;
        }
        
        footer {
            text-align: center;
            padding: 2rem;
            background: var(--dark);
            color: white;
            margin-top: 3rem;
        }
        
        @media (max-width: 768px) {
            .tools-grid {
                grid-template-columns: 1fr;
            }
            
            .container {
                padding: 1rem;
            }
        }