* {
            margin: 0;
            padding: 0;
            box-sizing: border-box;
        }

        :root {
            --primary: #3b82f6;
            --primary-dark: #2563eb;
            --secondary: #8b5cf6;
            --accent: #10b981;
            --warning: #f59e0b;
            --danger: #ef4444;
            --light: #f8fafc;
            --dark: #1e293b;
            --gray: #64748b;
            --gray-light: #e2e8f0;
            --card-bg: #ffffff;
            --premium-gradient: linear-gradient(135deg, #3b82f6, #8b5cf6, #6366f1);
            --success-gradient: linear-gradient(135deg, #10b981, #059669);
            --shadow: 0 10px 25px rgba(0, 0, 0, 0.05);
            --shadow-lg: 0 20px 40px rgba(0, 0, 0, 0.1);
            --radius: 16px;
            --radius-sm: 10px;
            --transition: all 0.3s ease;
        }

        body {
            font-family: 'Inter', sans-serif;
            background: linear-gradient(135deg, #f1f5f9 0%, #e2e8f0 100%);
            color: var(--dark);
            min-height: 100vh;
            padding: 20px;
            line-height: 1.6;
        }

        .container {
            max-width: 1400px;
            margin: 0 auto;
        }

        /* Header Styles */
        header {
            text-align: center;
            margin-bottom: 40px;
            padding-top: 20px;
        }

        .logo {
            display: flex;
            align-items: center;
            justify-content: center;
            gap: 15px;
            margin-bottom: 15px;
        }

        .logo-icon {
            background: var(--premium-gradient);
            width: 60px;
            height: 60px;
            border-radius: 50%;
            display: flex;
            align-items: center;
            justify-content: center;
            color: white;
            font-size: 28px;
            box-shadow: var(--shadow);
        }

        .logo-text {
            font-family: 'Poppins', sans-serif;
            font-size: 36px;
            font-weight: 800;
            background: var(--premium-gradient);
            -webkit-background-clip: text;
            -webkit-text-fill-color: transparent;
            background-clip: text;
            letter-spacing: -0.5px;
        }

        .tagline {
            color: var(--gray);
            font-size: 18px;
            max-width: 700px;
            margin: 0 auto 20px;
            font-weight: 500;
        }

        .premium-badge {
            display: inline-flex;
            align-items: center;
            gap: 10px;
            background: linear-gradient(135deg, #fbbf24, #f59e0b);
            color: #78350f;
            padding: 10px 25px;
            border-radius: 50px;
            font-weight: 700;
            font-size: 16px;
            box-shadow: 0 6px 15px rgba(245, 158, 11, 0.25);
        }

        /* Main Layout */
        .main-content {
            display: grid;
            grid-template-columns: 1.2fr 1fr;
            gap: 40px;
            margin-bottom: 50px;
        }

        @media (max-width: 1100px) {
            .main-content {
                grid-template-columns: 1fr;
                gap: 30px;
            }
        }

        /* Card Styles */
        .card {
            background: var(--card-bg);
            border-radius: var(--radius);
            padding: 35px;
            box-shadow: var(--shadow-lg);
            transition: var(--transition);
            height: 100%;
            display: flex;
            flex-direction: column;
        }

        .card:hover {
            transform: translateY(-5px);
            box-shadow: 0 25px 50px rgba(0, 0, 0, 0.12);
        }

        .card-title {
            font-family: 'Poppins', sans-serif;
            font-size: 24px;
            font-weight: 700;
            margin-bottom: 25px;
            color: var(--dark);
            display: flex;
            align-items: center;
            gap: 12px;
        }

        .card-title i {
            color: var(--primary);
        }

        /* Upload Area */
        .upload-area {
            border: 3px dashed var(--gray-light);
            border-radius: var(--radius);
            padding: 50px 30px;
            text-align: center;
            margin-bottom: 30px;
            transition: var(--transition);
            background: #f8fafc;
            cursor: pointer;
            position: relative;
            min-height: 300px;
            display: flex;
            flex-direction: column;
            justify-content: center;
            align-items: center;
        }

        .upload-area:hover {
            border-color: var(--primary);
            background: rgba(59, 130, 246, 0.03);
        }

        .upload-area.drag-over {
            border-color: var(--accent);
            background: rgba(16, 185, 129, 0.05);
        }

        .upload-icon {
            font-size: 70px;
            color: var(--primary);
            margin-bottom: 20px;
            opacity: 0.8;
        }

        .upload-text {
            font-size: 18px;
            font-weight: 600;
            margin-bottom: 10px;
            color: var(--dark);
        }

        .upload-subtext {
            color: var(--gray);
            margin-bottom: 25px;
        }

        .btn-upload {
            display: inline-flex;
            align-items: center;
            gap: 10px;
            background: var(--primary);
            color: white;
            padding: 14px 28px;
            border-radius: var(--radius-sm);
            font-weight: 600;
            font-size: 16px;
            border: none;
            cursor: pointer;
            transition: var(--transition);
        }

        .btn-upload:hover {
            background: var(--primary-dark);
            transform: translateY(-2px);
        }

        #file-input {
            display: none;
        }

        /* File List */
        .file-list {
            margin-top: 30px;
            max-height: 300px;
            overflow-y: auto;
        }

        .file-list-title {
            font-weight: 600;
            margin-bottom: 15px;
            color: var(--dark);
            display: flex;
            align-items: center;
            gap: 10px;
        }

        .file-item {
            display: flex;
            align-items: center;
            gap: 15px;
            padding: 15px;
            background: #f8fafc;
            border-radius: var(--radius-sm);
            margin-bottom: 10px;
            border: 1px solid var(--gray-light);
        }

        .file-icon {
            color: var(--danger);
            font-size: 24px;
        }

        .file-info {
            flex: 1;
        }

        .file-name {
            font-weight: 600;
            margin-bottom: 5px;
            word-break: break-all;
        }

        .file-size {
            font-size: 14px;
            color: var(--gray);
        }

        .file-actions {
            display: flex;
            gap: 10px;
        }

        .file-action-btn {
            background: none;
            border: none;
            color: var(--gray);
            cursor: pointer;
            font-size: 16px;
            transition: var(--transition);
            padding: 5px;
            border-radius: 4px;
        }

        .file-action-btn:hover {
            color: var(--danger);
            background: rgba(239, 68, 68, 0.1);
        }

        .file-action-btn.move:hover {
            color: var(--primary);
            background: rgba(59, 130, 246, 0.1);
        }

        /* Options Panel */
        .options-panel {
            margin-top: 30px;
        }

        .options-title {
            font-weight: 600;
            margin-bottom: 20px;
            color: var(--dark);
            font-size: 18px;
            display: flex;
            align-items: center;
            gap: 10px;
        }

        .options-grid {
            display: grid;
            grid-template-columns: repeat(2, 1fr);
            gap: 20px;
            margin-bottom: 25px;
        }

        @media (max-width: 768px) {
            .options-grid {
                grid-template-columns: 1fr;
            }
        }

        .option-group {
            background: #f8fafc;
            padding: 20px;
            border-radius: var(--radius-sm);
            border: 1px solid var(--gray-light);
        }

        .option-label {
            display: block;
            margin-bottom: 12px;
            font-weight: 600;
            color: var(--dark);
            display: flex;
            align-items: center;
            gap: 8px;
        }

        .select-box, .input-field {
            width: 100%;
            padding: 12px 15px;
            border: 2px solid var(--gray-light);
            border-radius: var(--radius-sm);
            font-family: 'Inter', sans-serif;
            font-size: 15px;
            background: white;
            transition: var(--transition);
        }

        .select-box:focus, .input-field:focus {
            outline: none;
            border-color: var(--primary);
            box-shadow: 0 0 0 3px rgba(59, 130, 246, 0.15);
        }

        .checkbox-group {
            display: flex;
            align-items: center;
            gap: 10px;
            margin-bottom: 15px;
        }

        .checkbox-group input[type="checkbox"] {
            width: 18px;
            height: 18px;
            accent-color: var(--primary);
        }

        /* Preview Section */
        .preview-section {
            display: flex;
            flex-direction: column;
        }

        .preview-header {
            display: flex;
            justify-content: space-between;
            align-items: center;
            margin-bottom: 20px;
            flex-wrap: wrap;
            gap: 15px;
        }

        .preview-actions {
            display: flex;
            gap: 12px;
        }

        .action-btn {
            padding: 10px 20px;
            border-radius: var(--radius-sm);
            border: none;
            font-weight: 600;
            font-size: 15px;
            cursor: pointer;
            transition: var(--transition);
            display: flex;
            align-items: center;
            gap: 8px;
        }

        .action-btn:hover {
            transform: translateY(-2px);
        }

        .action-btn.primary {
            background: var(--primary);
            color: white;
        }

        .action-btn.primary:hover {
            background: var(--primary-dark);
        }

        .action-btn.success {
            background: var(--success-gradient);
            color: white;
        }

        .action-btn.secondary {
            background: #f1f5f9;
            color: var(--gray);
        }

        .preview-container {
            flex-grow: 1;
            position: relative;
            border: 2px solid var(--gray-light);
            border-radius: var(--radius-sm);
            background: #f8fafc;
            overflow: hidden;
            min-height: 400px;
            display: flex;
            align-items: center;
            justify-content: center;
        }

        .preview-placeholder {
            text-align: center;
            color: var(--gray);
        }

        .preview-placeholder i {
            font-size: 70px;
            margin-bottom: 20px;
            opacity: 0.5;
        }

        .preview-image {
            max-width: 100%;
            max-height: 100%;
            object-fit: contain;
            display: none;
        }

        .image-counter {
            position: absolute;
            top: 15px;
            right: 15px;
            background: rgba(0, 0, 0, 0.7);
            color: white;
            padding: 6px 12px;
            border-radius: 20px;
            font-size: 14px;
            font-weight: 600;
        }

        .image-nav {
            position: absolute;
            top: 50%;
            width: 100%;
            display: flex;
            justify-content: space-between;
            padding: 0 20px;
            transform: translateY(-50%);
        }

        .nav-btn {
            background: rgba(0, 0, 0, 0.7);
            color: white;
            border: none;
            width: 50px;
            height: 50px;
            border-radius: 50%;
            display: flex;
            align-items: center;
            justify-content: center;
            font-size: 20px;
            cursor: pointer;
            transition: var(--transition);
        }

        .nav-btn:hover {
            background: rgba(0, 0, 0, 0.9);
            transform: scale(1.1);
        }

        .nav-btn:disabled {
            opacity: 0.5;
            cursor: not-allowed;
        }

        .nav-btn:disabled:hover {
            transform: none;
            background: rgba(0, 0, 0, 0.7);
        }

        /* PDF Preview */
        .pdf-preview {
            width: 100%;
            height: 100%;
            display: none;
            border: none;
        }

        /* Conversion Status */
        .conversion-status {
            margin-top: 25px;
            background: #f8fafc;
            border-radius: var(--radius-sm);
            padding: 20px;
            border: 1px solid var(--gray-light);
        }

        .status-title {
            font-weight: 600;
            margin-bottom: 15px;
            color: var(--dark);
            display: flex;
            align-items: center;
            gap: 10px;
        }

        .progress-bar {
            height: 10px;
            background: var(--gray-light);
            border-radius: 5px;
            margin-bottom: 15px;
            overflow: hidden;
        }

        .progress-fill {
            height: 100%;
            background: var(--success-gradient);
            border-radius: 5px;
            width: 0%;
            transition: width 0.5s ease;
        }

        .status-text {
            font-size: 14px;
            color: var(--gray);
            display: flex;
            justify-content: space-between;
        }

        /* AI Features Panel */
        .ai-features {
            background: var(--card-bg);
            border-radius: var(--radius);
            padding: 35px;
            box-shadow: var(--shadow-lg);
            margin-bottom: 50px;
        }

        .ai-header {
            display: flex;
            align-items: center;
            gap: 15px;
            margin-bottom: 25px;
        }

        .ai-icon {
            background: var(--premium-gradient);
            width: 50px;
            height: 50px;
            border-radius: 50%;
            display: flex;
            align-items: center;
            justify-content: center;
            color: white;
            font-size: 22px;
        }

        .features-grid {
            display: grid;
            grid-template-columns: repeat(auto-fit, minmax(300px, 1fr));
            gap: 25px;
        }

        .feature-card {
            background: #f8fafc;
            border-radius: var(--radius-sm);
            padding: 25px;
            border-left: 4px solid var(--primary);
        }

        .feature-title {
            font-weight: 700;
            font-size: 18px;
            margin-bottom: 10px;
            color: var(--dark);
            display: flex;
            align-items: center;
            gap: 10px;
        }

        .feature-title i {
            color: var(--primary);
        }

        /* Premium Features */
        .premium-features {
            display: grid;
            grid-template-columns: repeat(auto-fit, minmax(280px, 1fr));
            gap: 25px;
            margin-bottom: 60px;
        }

        .feature-card-large {
            background: var(--card-bg);
            border-radius: var(--radius);
            padding: 30px;
            box-shadow: var(--shadow);
            transition: var(--transition);
            text-align: center;
            border-top: 4px solid var(--primary);
        }

        .feature-card-large:hover {
            transform: translateY(-8px);
            box-shadow: var(--shadow-lg);
        }

        .feature-icon-large {
            width: 70px;
            height: 70px;
            border-radius: 50%;
            display: flex;
            align-items: center;
            justify-content: center;
            font-size: 28px;
            margin: 0 auto 20px;
            background: var(--premium-gradient);
            color: white;
        }

        .feature-title-large {
            font-size: 20px;
            font-weight: 700;
            margin-bottom: 12px;
            color: var(--dark);
        }

        /* Footer */
        footer {
            text-align: center;
            padding: 30px 0;
            border-top: 1px solid var(--gray-light);
            color: var(--gray);
            font-size: 15px;
        }

        footer p {
            margin-bottom: 10px;
        }

        .footer-links {
            display: flex;
            justify-content: center;
            gap: 25px;
            margin-top: 20px;
            flex-wrap: wrap;
        }

        .footer-link {
            color: var(--primary);
            text-decoration: none;
            font-weight: 500;
            transition: var(--transition);
        }

        .footer-link:hover {
            color: var(--primary-dark);
            text-decoration: underline;
        }

        /* Loading Animation */
        .loading {
            display: none;
            text-align: center;
            padding: 20px;
        }

        .loading-spinner {
            width: 50px;
            height: 50px;
            border: 5px solid var(--gray-light);
            border-top: 5px solid var(--primary);
            border-radius: 50%;
            animation: spin 1s linear infinite;
            margin: 0 auto 15px;
        }

        @keyframes spin {
            0% { transform: rotate(0deg); }
            100% { transform: rotate(360deg); }
        }

        /* Toast Notification */
        .toast {
            position: fixed;
            bottom: 30px;
            right: 30px;
            background: var(--success-gradient);
            color: white;
            padding: 15px 25px;
            border-radius: var(--radius-sm);
            font-weight: 600;
            box-shadow: var(--shadow-lg);
            z-index: 1000;
            transform: translateY(100px);
            opacity: 0;
            transition: transform 0.3s ease, opacity 0.3s ease;
        }

        .toast.show {
            transform: translateY(0);
            opacity: 1;
        }

        /* Responsive Adjustments */
        @media (max-width: 768px) {
            body {
                padding: 15px;
            }
            
            .card {
                padding: 25px 20px;
            }
            
            .logo-text {
                font-size: 28px;
            }
            
            .premium-badge {
                font-size: 14px;
                padding: 8px 18px;
            }
            
            .upload-area {
                padding: 30px 20px;
                min-height: 250px;
            }
            
            .upload-icon {
                font-size: 50px;
            }
            
            .preview-header {
                flex-direction: column;
                align-items: flex-start;
            }
            
            .preview-actions {
                width: 100%;
                justify-content: space-between;
            }
            
            .action-btn {
                flex: 1;
                justify-content: center;
            }
        }

        @media (max-width: 480px) {
            .logo {
                flex-direction: column;
                gap: 10px;
            }
            
            .logo-text {
                font-size: 24px;
            }
            
            .tagline {
                font-size: 16px;
            }
            
            .card-title {
                font-size: 22px;
            }
            
            .file-item {
                flex-direction: column;
                align-items: flex-start;
                gap: 10px;
            }
            
            .file-actions {
                align-self: flex-end;
            }
        }

        /* Tooltip */
        .tooltip {
            position: relative;
            display: inline-block;
        }

        .tooltip .tooltip-text {
            visibility: hidden;
            width: 200px;
            background-color: var(--dark);
            color: white;
            text-align: center;
            border-radius: var(--radius-sm);
            padding: 10px;
            position: absolute;
            z-index: 1;
            bottom: 125%;
            left: 50%;
            transform: translateX(-50%);
            opacity: 0;
            transition: opacity 0.3s;
            font-size: 14px;
            font-weight: normal;
        }

        .tooltip .tooltip-text::after {
            content: "";
            position: absolute;
            top: 100%;
            left: 50%;
            margin-left: -5px;
            border-width: 5px;
            border-style: solid;
            border-color: var(--dark) transparent transparent transparent;
        }

        .tooltip:hover .tooltip-text {
            visibility: visible;
            opacity: 1;
        }