:root {
            --primary-gradient: linear-gradient(135deg, #4f46e5 0%, #7c3aed 100%);
            --secondary-gradient: linear-gradient(135deg, #ec4899 0%, #8b5cf6 100%);
            --success-gradient: linear-gradient(135deg, #10b981 0%, #059669 100%);
            --warning-gradient: linear-gradient(135deg, #f59e0b 0%, #d97706 100%);
            --danger-gradient: linear-gradient(135deg, #ef4444 0%, #dc2626 100%);
            --dark-gradient: linear-gradient(135deg, #1f2937 0%, #111827 100%);
            --primary-color: #4f46e5;
            --primary-dark: #4338ca;
            --primary-light: #818cf8;
            --success-color: #10b981;
            --warning-color: #f59e0b;
            --danger-color: #ef4444;
            --dark-color: #1f2937;
            --light-color: #f9fafb;
            --gray-100: #f3f4f6;
            --gray-200: #e5e7eb;
            --gray-300: #d1d5db;
            --gray-400: #9ca3af;
            --gray-500: #6b7280;
            --shadow-sm: 0 2px 8px rgba(0, 0, 0, 0.08);
            --shadow-md: 0 8px 30px rgba(0, 0, 0, 0.12);
            --shadow-lg: 0 20px 60px rgba(0, 0, 0, 0.15);
            --shadow-xl: 0 25px 80px rgba(0, 0, 0, 0.2);
            --radius-sm: 12px;
            --radius-md: 20px;
            --radius-lg: 28px;
            --radius-xl: 36px;
            --transition-fast: all 0.2s cubic-bezier(0.4, 0, 0.2, 1);
            --transition: all 0.3s cubic-bezier(0.4, 0, 0.2, 1);
            --transition-slow: all 0.5s cubic-bezier(0.4, 0, 0.2, 1);
        }
        
        * {
            margin: 0;
            padding: 0;
            box-sizing: border-box;
        }
        
        body {
            font-family: 'Inter', -apple-system, BlinkMacSystemFont, 'Segoe UI', Roboto, sans-serif;
            background: linear-gradient(135deg, #f9fafb 0%, #f3f4f6 100%);
            color: var(--dark-color);
            line-height: 1.7;
            min-height: 100vh;
            overflow-x: hidden;
            position: relative;
            font-size: 16px;
            -webkit-font-smoothing: antialiased;
            -moz-osx-font-smoothing: grayscale;
        }
        
        body::before {
            content: '';
            position: fixed;
            top: 0;
            left: 0;
            right: 0;
            bottom: 0;
            background: 
                radial-gradient(circle at 10% 20%, rgba(79, 70, 229, 0.05) 0%, transparent 20%),
                radial-gradient(circle at 90% 80%, rgba(236, 72, 153, 0.05) 0%, transparent 20%),
                radial-gradient(circle at 50% 50%, rgba(16, 185, 129, 0.03) 0%, transparent 30%);
            z-index: -1;
            pointer-events: none;
        }
        
        h1, h2, h3, h4, h5, h6 {
            font-family: 'Poppins', sans-serif;
            font-weight: 700;
            line-height: 1.3;
            color: var(--dark-color);
        }
        
        /* ===== NAVIGATION ===== */
        .main-nav {
            background: rgba(255, 255, 255, 0.98);
            backdrop-filter: blur(20px);
            -webkit-backdrop-filter: blur(20px);
            border-bottom: 1px solid rgba(79, 70, 229, 0.08);
            box-shadow: 0 8px 32px rgba(79, 70, 229, 0.1);
            padding: 1.2rem 0;
            transition: var(--transition);
            position: sticky;
            top: 0;
            width: 100%;
            z-index: 1000;
        }
        
        .nav-scrolled {
            padding: 0.8rem 0;
            box-shadow: 0 10px 40px rgba(79, 70, 229, 0.15);
            background: rgba(255, 255, 255, 0.98);
        }
        
        .logo-text {
            background: var(--primary-gradient);
            -webkit-background-clip: text;
            -webkit-text-fill-color: transparent;
            font-weight: 800;
            font-size: 2rem;
            letter-spacing: -0.5px;
            transition: var(--transition);
        }
        
        .logo-text:hover {
            opacity: 0.9;
            transform: scale(1.02);
        }
        
        /* ===== HERO SECTION ===== */
        .hero-section {
            padding: 180px 0 100px;
            background: var(--primary-gradient);
            color: white;
            position: relative;
            overflow: hidden;
            clip-path: polygon(0 0, 100% 0, 100% 90%, 0% 100%);
        }
        
        .hero-section::before {
            content: '';
            position: absolute;
            top: 0;
            left: 0;
            right: 0;
            bottom: 0;
            background: 
                radial-gradient(circle at 20% 30%, rgba(255,255,255,0.1) 0%, transparent 50%),
                radial-gradient(circle at 80% 70%, rgba(236, 72, 153, 0.1) 0%, transparent 50%);
            pointer-events: none;
        }
        
        .hero-title {
            font-size: clamp(2.5rem, 5vw, 4rem);
            font-weight: 800;
            margin-bottom: 1.5rem;
            line-height: 1.1;
            text-shadow: 0 4px 20px rgba(0,0,0,0.2);
        }
        
        .hero-subtitle {
            font-size: clamp(1rem, 2vw, 1.3rem);
            opacity: 0.95;
            margin-bottom: 2.5rem;
            max-width: 700px;
            line-height: 1.6;
        }
        
        .hero-badge {
            background: rgba(255,255,255,0.2);
            backdrop-filter: blur(10px);
            -webkit-backdrop-filter: blur(10px);
            border-radius: 50px;
            padding: 0.5rem 1.5rem;
            font-weight: 500;
            display: inline-flex;
            align-items: center;
            gap: 0.5rem;
            border: 1px solid rgba(255,255,255,0.1);
            margin-right: 1rem;
            margin-bottom: 1rem;
        }
        
        .brand-badge {
            background: rgba(255,255,255,0.15);
            backdrop-filter: blur(10px);
            -webkit-backdrop-filter: blur(10px);
            border-radius: 50px;
            padding: 0.4rem 1.2rem;
            font-size: 0.9rem;
            display: inline-flex;
            align-items: center;
            gap: 0.5rem;
            border: 1px solid rgba(255,255,255,0.2);
            margin-right: 0.5rem;
            margin-bottom: 0.5rem;
            transition: var(--transition-fast);
        }
        
        .brand-badge:hover {
            background: rgba(255,255,255,0.25);
            transform: translateY(-2px);
        }
        
        .try-sample-btn {
            background: rgba(255, 255, 255, 0.2);
            border: 2px solid rgba(255, 255, 255, 0.3);
            color: white;
            padding: 1rem 2rem;
            border-radius: 50px;
            font-weight: 600;
            transition: var(--transition);
            backdrop-filter: blur(10px);
            -webkit-backdrop-filter: blur(10px);
        }
        
        .try-sample-btn:hover {
            background: rgba(255, 255, 255, 0.3);
            border-color: rgba(255, 255, 255, 0.5);
            transform: translateY(-3px);
            color: white;
        }
        
        /* ===== STEP INDICATOR ===== */
        .step-indicator {
            display: flex;
            justify-content: space-between;
            align-items: center;
            margin: 3rem 0;
            position: relative;
        }
        
        .step-indicator::before {
            content: '';
            position: absolute;
            top: 35px;
            left: 10%;
            right: 10%;
            height: 3px;
            background: var(--gray-200);
            z-index: 1;
        }
        
        .step {
            text-align: center;
            z-index: 2;
            position: relative;
            flex: 1;
        }
        
        .step-number {
            width: 70px;
            height: 70px;
            border-radius: 50%;
            background: var(--gray-200);
            color: var(--gray-500);
            display: flex;
            align-items: center;
            justify-content: center;
            margin: 0 auto 10px;
            font-weight: bold;
            font-size: 1.5rem;
            border: 3px solid white;
            transition: var(--transition);
        }
        
        .step.active .step-number {
            background: var(--primary-gradient);
            color: white;
            box-shadow: 0 0 0 5px rgba(79, 70, 229, 0.2);
            transform: scale(1.1);
        }
        
        .step.completed .step-number {
            background: var(--success-gradient);
            color: white;
        }
        
        .step-label {
            font-weight: 600;
            color: var(--gray-500);
            transition: var(--transition);
            font-size: 1rem;
        }
        
        .step.active .step-label {
            color: var(--primary-color);
            font-weight: 700;
        }
        
        /* ===== TOOL SECTION ===== */
        .tool-section {
            margin-top: -50px;
            position: relative;
            z-index: 10;
            padding-bottom: 100px;
        }
        
        .upload-card {
            background: white;
            border-radius: var(--radius-lg);
            padding: clamp(1.5rem, 3vw, 2.5rem);
            box-shadow: var(--shadow-xl);
            border: 2px solid rgba(79, 70, 229, 0.1);
            transition: var(--transition);
            position: relative;
            overflow: hidden;
        }
        
        .upload-card::before {
            content: '';
            position: absolute;
            top: 0;
            left: 0;
            right: 0;
            height: 6px;
            background: var(--primary-gradient);
        }
        
        .upload-card:hover {
            transform: translateY(-10px);
            box-shadow: 0 35px 90px rgba(79, 70, 229, 0.25);
        }
        
        /* ===== UPLOAD AREA ===== */
        .upload-area {
            border: 3px dashed rgba(79, 70, 229, 0.3);
            border-radius: var(--radius-md);
            padding: clamp(2rem, 4vw, 3.5rem);
            text-align: center;
            background: linear-gradient(135deg, rgba(79, 70, 229, 0.05) 0%, rgba(124, 58, 237, 0.05) 100%);
            cursor: pointer;
            transition: var(--transition);
            position: relative;
            overflow: hidden;
            margin-bottom: 2rem;
        }
        
        .upload-area:hover {
            border-color: var(--primary-color);
            background: linear-gradient(135deg, rgba(79, 70, 229, 0.1) 0%, rgba(124, 58, 237, 0.1) 100%);
            transform: translateY(-5px);
        }
        
        .upload-area.dragover {
            border-color: var(--primary-color);
            background: rgba(79, 70, 229, 0.15);
            transform: scale(1.02);
        }
        
        .upload-area::before {
            content: '';
            position: absolute;
            top: 0;
            left: -100%;
            width: 100%;
            height: 100%;
            background: linear-gradient(90deg, transparent, rgba(255,255,255,0.4), transparent);
            transition: left 0.5s;
        }
        
        .upload-area:hover::before {
            left: 100%;
        }
        
        .upload-icon {
            width: 90px;
            height: 90px;
            background: var(--primary-gradient);
            border-radius: 50%;
            display: flex;
            align-items: center;
            justify-content: center;
            margin: 0 auto 1.5rem;
            font-size: 2.5rem;
            color: white;
            box-shadow: 0 15px 35px rgba(79, 70, 229, 0.4);
            transition: var(--transition);
            animation: float 6s ease-in-out infinite;
        }
        
        .upload-area:hover .upload-icon {
            transform: rotate(10deg) scale(1.1);
        }
        
        @keyframes float {
            0%, 100% { transform: translateY(0); }
            50% { transform: translateY(-10px); }
        }
        
        .upload-btn {
            background: var(--primary-gradient);
            color: white;
            border: none;
            padding: 1rem 2rem;
            border-radius: 50px;
            font-weight: 600;
            font-size: 1.1rem;
            transition: var(--transition);
            box-shadow: 0 10px 20px rgba(79, 70, 229, 0.3);
            display: inline-flex;
            align-items: center;
            gap: 10px;
            position: relative;
            overflow: hidden;
        }
        
        .upload-btn::before {
            content: '';
            position: absolute;
            top: 50%;
            left: 50%;
            width: 0;
            height: 0;
            border-radius: 50%;
            background: rgba(255, 255, 255, 0.3);
            transform: translate(-50%, -50%);
            transition: width 0.6s, height 0.6s;
        }
        
        .upload-btn:hover::before {
            width: 300px;
            height: 300px;
        }
        
        .upload-btn:hover {
            transform: translateY(-3px);
            box-shadow: 0 15px 30px rgba(79, 70, 229, 0.4);
        }
        
        /* ===== FILE LIST ===== */
        .file-list {
            max-height: 300px;
            overflow-y: auto;
            margin: 1.5rem 0;
            border: 2px solid var(--gray-200);
            border-radius: var(--radius-sm);
            padding: 0.5rem;
            background: white;
        }
        
        .file-item {
            display: flex;
            align-items: center;
            padding: 0.75rem;
            border-bottom: 1px solid var(--gray-200);
            transition: var(--transition-fast);
            background: white;
            border-radius: 8px;
        }
        
        .file-item:hover {
            background: var(--gray-100);
            transform: translateX(5px);
        }
        
        .file-item:last-child {
            border-bottom: none;
        }
        
        .file-icon {
            width: 40px;
            height: 40px;
            background: var(--primary-gradient);
            border-radius: 8px;
            display: flex;
            align-items: center;
            justify-content: center;
            color: white;
            margin-right: 1rem;
            flex-shrink: 0;
        }
        
        .file-info {
            flex: 1;
            min-width: 0;
        }
        
        .file-name {
            font-weight: 600;
            margin-bottom: 2px;
            white-space: nowrap;
            overflow: hidden;
            text-overflow: ellipsis;
        }
        
        .file-meta {
            font-size: 0.85rem;
            color: var(--gray-500);
            display: flex;
            gap: 15px;
        }
        
        .remove-file {
            color: var(--danger-color);
            cursor: pointer;
            padding: 0.5rem;
            border-radius: 50%;
            transition: var(--transition-fast);
            flex-shrink: 0;
        }
        
        .remove-file:hover {
            background: rgba(239, 68, 68, 0.1);
            transform: scale(1.1);
        }
        
        .files-counter {
            background: var(--primary-gradient);
            color: white;
            padding: 0.25rem 0.75rem;
            border-radius: 50px;
            font-size: 0.85rem;
            margin-left: 10px;
            display: inline-block;
        }
        
        /* ===== SUPPORTED FORMATS ===== */
        .formats-list {
            display: grid;
            grid-template-columns: repeat(auto-fill, minmax(100px, 1fr));
            gap: 10px;
            margin: 1.5rem 0;
        }
        
        .format-item {
            background: var(--gray-100);
            border-radius: 8px;
            padding: 0.5rem;
            text-align: center;
            font-size: 0.85rem;
            border: 1px solid var(--gray-200);
            transition: var(--transition-fast);
            font-weight: 500;
        }
        
        .format-item:hover {
            background: var(--primary-gradient);
            color: white;
            transform: translateY(-2px);
            box-shadow: var(--shadow-md);
        }
        
        /* ===== SAMPLE FILES ===== */
        .sample-files {
            background: rgba(79, 70, 229, 0.05);
            border-radius: var(--radius-md);
            padding: 1.5rem;
            margin: 1.5rem 0;
            border: 2px solid rgba(79, 70, 229, 0.1);
        }
        
        .sample-item {
            display: flex;
            align-items: center;
            padding: 0.75rem;
            background: white;
            border-radius: 10px;
            margin-bottom: 0.5rem;
            border: 1px solid var(--gray-200);
            transition: var(--transition-fast);
        }
        
        .sample-item:hover {
            transform: translateX(5px);
            border-color: var(--primary-color);
            box-shadow: var(--shadow-sm);
        }
        
        .sample-item:last-child {
            margin-bottom: 0;
        }
        
        /* ===== PREVIEW SECTION ===== */
        .preview-section {
            background: var(--dark-gradient);
            border-radius: var(--radius-lg);
            padding: 2rem;
            color: white;
            box-shadow: var(--shadow-xl);
            height: 100%;
            position: relative;
            overflow: hidden;
        }
        
        .preview-section::before {
            content: '';
            position: absolute;
            top: 0;
            left: 0;
            right: 0;
            height: 6px;
            background: var(--secondary-gradient);
        }
        
        .preview-container {
            display: flex;
            flex-wrap: wrap;
            gap: 15px;
            margin: 1.5rem 0;
            max-height: 500px;
            overflow-y: auto;
            padding: 10px;
            background: rgba(0, 0, 0, 0.3);
            border-radius: var(--radius-md);
            scrollbar-width: thin;
            scrollbar-color: var(--primary-color) rgba(255,255,255,0.1);
        }
        
        .preview-container::-webkit-scrollbar {
            width: 8px;
        }
        
        .preview-container::-webkit-scrollbar-track {
            background: rgba(255,255,255,0.1);
            border-radius: 4px;
        }
        
        .preview-container::-webkit-scrollbar-thumb {
            background: var(--primary-gradient);
            border-radius: 4px;
        }
        
        .preview-item {
            width: calc(50% - 10px);
            position: relative;
            border-radius: 10px;
            overflow: hidden;
            cursor: pointer;
            transition: var(--transition);
        }
        
        @media (min-width: 768px) {
            .preview-item {
                width: calc(33.333% - 10px);
            }
        }
        
        .preview-item:hover {
            transform: translateY(-5px) scale(1.02);
            box-shadow: 0 10px 20px rgba(0, 0, 0, 0.5);
        }
        
        .preview-image {
            width: 100%;
            height: 150px;
            object-fit: cover;
            display: block;
        }
        
        .preview-overlay {
            position: absolute;
            bottom: 0;
            left: 0;
            right: 0;
            background: linear-gradient(to top, rgba(0,0,0,0.9), transparent);
            padding: 10px;
            font-size: 0.8rem;
            color: white;
        }
        
        .preview-filename {
            white-space: nowrap;
            overflow: hidden;
            text-overflow: ellipsis;
            margin-bottom: 3px;
            font-weight: 500;
        }
        
        .preview-brand {
            font-size: 0.7rem;
            opacity: 0.8;
        }
        
        .control-buttons {
            display: flex;
            gap: 10px;
            flex-wrap: wrap;
        }
        
        .control-btn {
            background: rgba(255, 255, 255, 0.1);
            border: 1px solid rgba(255, 255, 255, 0.2);
            color: white;
            border-radius: 50px;
            padding: 0.5rem 1.2rem;
            transition: var(--transition-fast);
            display: inline-flex;
            align-items: center;
            gap: 5px;
            font-size: 0.9rem;
        }
        
        .control-btn:hover {
            background: rgba(255, 255, 255, 0.2);
            transform: translateY(-2px);
        }
        
        /* ===== SETTINGS PANEL ===== */
        .settings-panel {
            background: white;
            border-radius: var(--radius-md);
            padding: 2rem;
            margin: 1.5rem 0;
            box-shadow: var(--shadow-lg);
            border: 2px solid var(--gray-200);
        }
        
        .setting-group {
            margin-bottom: 2rem;
        }
        
        .setting-label {
            display: flex;
            align-items: center;
            gap: 0.5rem;
            font-weight: 600;
            margin-bottom: 1rem;
            color: var(--dark-color);
            font-size: 1.1rem;
        }
        
        .setting-label i {
            color: var(--primary-color);
            font-size: 1.2rem;
        }
        
        .options-grid {
            display: grid;
            grid-template-columns: repeat(auto-fit, minmax(200px, 1fr));
            gap: 1rem;
            margin-top: 0.5rem;
        }
        
        .option-card {
            background: var(--gray-100);
            border: 2px solid var(--gray-200);
            border-radius: var(--radius-sm);
            padding: 1.5rem;
            text-align: center;
            cursor: pointer;
            transition: var(--transition);
        }
        
        .option-card:hover {
            border-color: var(--primary-color);
            background: rgba(79, 70, 229, 0.05);
            transform: translateY(-3px);
        }
        
        .option-card.selected {
            border-color: var(--primary-color);
            background: rgba(79, 70, 229, 0.1);
            box-shadow: 0 5px 15px rgba(79, 70, 229, 0.2);
        }
        
        .option-card i {
            font-size: 2rem;
            color: var(--primary-color);
            margin-bottom: 0.5rem;
        }
        
        /* Layout preview */
        .layout-preview {
            margin-top: 1rem;
            display: flex;
            justify-content: center;
        }
        
        .layout-single {
            width: 100px;
            height: 130px;
            background: var(--gray-300);
            border-radius: 8px;
            position: relative;
            overflow: hidden;
        }
        
        .layout-single::after {
            content: '';
            position: absolute;
            top: 15px;
            left: 15px;
            right: 15px;
            bottom: 15px;
            background: var(--primary-gradient);
            border-radius: 4px;
        }
        
        .layout-grid {
            width: 100px;
            height: 130px;
            background: var(--gray-300);
            border-radius: 8px;
            position: relative;
            overflow: hidden;
            display: grid;
            grid-template-columns: 1fr 1fr;
            grid-template-rows: 1fr 1fr;
            gap: 5px;
            padding: 5px;
        }
        
        .layout-grid-cell {
            background: var(--primary-gradient);
            border-radius: 3px;
        }
        
        /* ===== ACTION BUTTONS ===== */
        .btn-primary {
            background: var(--primary-gradient);
            color: white;
            border: none;
            padding: 1rem 2rem;
            border-radius: 50px;
            font-weight: 600;
            transition: var(--transition);
            box-shadow: 0 10px 20px rgba(79, 70, 229, 0.3);
            display: inline-flex;
            align-items: center;
            justify-content: center;
            gap: 10px;
            position: relative;
            overflow: hidden;
        }
        
        .btn-primary::before {
            content: '';
            position: absolute;
            top: 50%;
            left: 50%;
            width: 0;
            height: 0;
            border-radius: 50%;
            background: rgba(255, 255, 255, 0.3);
            transform: translate(-50%, -50%);
            transition: width 0.6s, height 0.6s;
        }
        
        .btn-primary:hover::before {
            width: 300px;
            height: 300px;
        }
        
        .btn-primary:hover {
            transform: translateY(-3px);
            box-shadow: 0 15px 30px rgba(79, 70, 229, 0.4);
        }
        
        .btn-success {
            background: var(--success-gradient);
            color: white;
            border: none;
            padding: 1rem 2rem;
            border-radius: 50px;
            font-weight: 600;
            transition: var(--transition);
            box-shadow: 0 10px 20px rgba(16, 185, 129, 0.3);
        }
        
        .btn-success:hover {
            transform: translateY(-3px);
            box-shadow: 0 15px 30px rgba(16, 185, 129, 0.4);
        }
        
        .btn-outline-primary {
            background: transparent;
            border: 2px solid var(--primary-color);
            color: var(--primary-color);
            padding: 1rem 2rem;
            border-radius: 50px;
            font-weight: 600;
            transition: var(--transition);
        }
        
        .btn-outline-primary:hover {
            background: var(--primary-gradient);
            color: white;
            transform: translateY(-3px);
        }
        
        /* ===== RESULT CARD ===== */
        .result-card {
            background: var(--success-gradient);
            color: white;
            border-radius: var(--radius-md);
            padding: 2.5rem;
            text-align: center;
            box-shadow: 0 20px 40px rgba(16, 185, 129, 0.3);
            animation: pulse 2s infinite;
        }
        
        @keyframes pulse {
            0% { transform: scale(1); }
            50% { transform: scale(1.01); }
            100% { transform: scale(1); }
        }
        
        .result-icon {
            font-size: 4rem;
            margin-bottom: 1rem;
        }
        
        .result-number {
            font-size: 3rem;
            font-weight: 800;
            line-height: 1;
            margin: 1rem 0;
            text-shadow: 0 5px 15px rgba(0, 0, 0, 0.2);
        }
        
        /* ===== FEATURE CARDS ===== */
        .feature-card {
            background: white;
            border-radius: var(--radius-md);
            padding: 2rem;
            height: 100%;
            transition: var(--transition);
            border: 2px solid transparent;
            position: relative;
            overflow: hidden;
            box-shadow: var(--shadow-md);
        }
        
        .feature-card::before {
            content: '';
            position: absolute;
            top: 0;
            left: 0;
            right: 0;
            height: 6px;
            background: var(--primary-gradient);
            transform: scaleX(0);
            transition: transform 0.4s ease;
        }
        
        .feature-card:hover::before {
            transform: scaleX(1);
        }
        
        .feature-card:hover {
            transform: translateY(-10px);
            box-shadow: var(--shadow-xl);
            border-color: rgba(79, 70, 229, 0.2);
        }
        
        .feature-icon {
            width: 70px;
            height: 70px;
            border-radius: 20px;
            display: flex;
            align-items: center;
            justify-content: center;
            font-size: 2rem;
            margin-bottom: 1.5rem;
            background: var(--primary-gradient);
            color: white;
            box-shadow: 0 10px 25px rgba(79, 70, 229, 0.3);
            transition: var(--transition);
        }
        
        .feature-card:hover .feature-icon {
            transform: rotate(10deg) scale(1.1);
        }
        
        /* ===== STEP CARDS ===== */
        .step-card {
            background: white;
            border-radius: var(--radius-md);
            padding: 2rem;
            text-align: center;
            height: 100%;
            position: relative;
            border: 2px solid transparent;
            transition: var(--transition);
            box-shadow: var(--shadow-md);
        }
        
        .step-card:hover {
            border-color: var(--primary-color);
            transform: translateY(-5px);
            box-shadow: var(--shadow-xl);
        }
        
        .step-number {
            width: 60px;
            height: 60px;
            background: var(--primary-gradient);
            color: white;
            border-radius: 50%;
            display: flex;
            align-items: center;
            justify-content: center;
            font-weight: 700;
            font-size: 1.5rem;
            margin: 0 auto 1.5rem;
        }
        
        /* ===== RELATED TOOLS GRID ===== */
        .related-tools-grid {
            display: grid;
            grid-template-columns: repeat(auto-fit, minmax(180px, 1fr));
            gap: 20px;
            margin: 50px 0;
        }
        
        .tool-card {
            background: white;
            padding: 1.5rem;
            border-radius: var(--radius-md);
            text-align: center;
            box-shadow: var(--shadow-md);
            transition: var(--transition);
            border: 2px solid transparent;
            text-decoration: none;
            color: var(--dark-color);
            display: block;
        }
        
        .tool-card:hover {
            border-color: var(--primary-color);
            transform: translateY(-8px) scale(1.02);
            box-shadow: var(--shadow-xl);
            text-decoration: none;
            color: var(--dark-color);
        }
        
        .tool-icon {
            font-size: 2.5rem;
            margin-bottom: 15px;
            display: block;
            color: var(--primary-color);
        }
        
        .tool-name {
            font-weight: 700;
            font-size: 1.1rem;
            margin-bottom: 8px;
            color: var(--dark-color);
        }
        
        .tool-desc {
            color: var(--gray-500);
            font-size: 0.85rem;
            line-height: 1.5;
        }
        
        /* ===== FAQ SECTION ===== */
        .faq-section {
            padding: 100px 0;
            background: linear-gradient(135deg, #f9fafb 0%, #f3f4f6 100%);
        }
        
        .accordion-item {
            border: none;
            margin-bottom: 1rem;
            border-radius: var(--radius-md) !important;
            overflow: hidden;
            box-shadow: var(--shadow-sm);
            background: white;
            transition: var(--transition);
        }
        
        .accordion-item:hover {
            box-shadow: var(--shadow-md);
            transform: translateY(-2px);
        }
        
        .accordion-button {
            background: white;
            border: none;
            padding: 1.5rem;
            font-weight: 600;
            font-size: 1.1rem;
            color: var(--dark-color);
            transition: var(--transition);
        }
        
        .accordion-button:not(.collapsed) {
            background: rgba(79, 70, 229, 0.08);
            color: var(--primary-color);
            box-shadow: none;
        }
        
        .accordion-button:focus {
            box-shadow: none;
            border-color: rgba(79, 70, 229, 0.25);
        }
        
        .accordion-button::after {
            background-image: url("data:image/svg+xml,%3csvg xmlns='http://www.w3.org/2000/svg' viewBox='0 0 16 16' fill='%234f46e5'%3e%3cpath fill-rule='evenodd' d='M1.646 4.646a.5.5 0 0 1 .708 0L8 10.293l5.646-5.647a.5.5 0 0 1 .708.708l-6 6a.5.5 0 0 1-.708 0l-6-6a.5.5 0 0 1 0-.708z'/%3e%3c/svg%3e");
            transform: scale(1.2);
        }
        
        .accordion-body {
            padding: 1.5rem;
            background: var(--gray-100);
            color: var(--gray-600);
            line-height: 1.8;
        }
        
        /* ===== BENEFIT BOX ===== */
        .benefit-box {
            background: linear-gradient(135deg, rgba(79, 70, 229, 0.05) 0%, rgba(124, 58, 237, 0.05) 100%);
            border-radius: var(--radius-md);
            padding: 2rem;
            border-left: 6px solid var(--primary-color);
            margin: 2rem 0;
        }
        
        .benefit-list {
            list-style: none;
            padding: 0;
        }
        
        .benefit-list li {
            padding: 0.8rem 0;
            display: flex;
            align-items: flex-start;
            gap: 15px;
            color: var(--dark-color);
            border-bottom: 1px solid rgba(79, 70, 229, 0.1);
        }
        
        .benefit-list li:last-child {
            border-bottom: none;
        }
        
        .benefit-list i {
            color: var(--primary-color);
            margin-top: 3px;
            flex-shrink: 0;
        }
        
        /* ===== LOADING OVERLAY ===== */
        .loading-overlay {
            position: fixed;
            top: 0;
            left: 0;
            right: 0;
            bottom: 0;
            background: rgba(255, 255, 255, 0.95);
            display: none;
            align-items: center;
            justify-content: center;
            z-index: 9999;
            backdrop-filter: blur(20px);
            -webkit-backdrop-filter: blur(20px);
        }
        
        .loading-overlay.active {
            display: flex;
            animation: fadeIn 0.3s ease;
        }
        
        @keyframes fadeIn {
            from { opacity: 0; }
            to { opacity: 1; }
        }
        
        .loading-spinner {
            width: 80px;
            height: 80px;
            border: 5px solid var(--gray-200);
            border-top: 5px solid var(--primary-color);
            border-radius: 50%;
            animation: spin 1s linear infinite;
            margin-bottom: 2rem;
        }
        
        @keyframes spin {
            0% { transform: rotate(0deg); }
            100% { transform: rotate(360deg); }
        }
        
        /* ===== NOTIFICATION ===== */
        .notification {
            position: fixed;
            top: 100px;
            right: 20px;
            padding: 1rem 1.5rem;
            border-radius: var(--radius-sm);
            color: white;
            font-weight: 600;
            z-index: 1000;
            opacity: 0;
            transform: translateX(100%);
            transition: all 0.3s ease;
            max-width: 350px;
            box-shadow: var(--shadow-lg);
            backdrop-filter: blur(10px);
            -webkit-backdrop-filter: blur(10px);
        }
        
        .notification.show {
            opacity: 1;
            transform: translateX(0);
        }
        
        .notification.success {
            background: linear-gradient(135deg, #10b981, #059669);
        }
        
        .notification.error {
            background: linear-gradient(135deg, #ef4444, #dc2626);
        }
        
        .notification.warning {
            background: linear-gradient(135deg, #f59e0b, #d97706);
        }
        
        .notification.info {
            background: linear-gradient(135deg, #4f46e5, #7c3aed);
        }
        
        /* ===== BACK TO TOP ===== */
        .back-to-top {
            position: fixed;
            bottom: 40px;
            right: 40px;
            width: 60px;
            height: 60px;
            background: var(--primary-gradient);
            color: white;
            border: none;
            border-radius: 50%;
            display: none;
            align-items: center;
            justify-content: center;
            font-size: 1.5rem;
            cursor: pointer;
            z-index: 1000;
            box-shadow: var(--shadow-lg);
            transition: var(--transition);
        }
        
        .back-to-top.show {
            display: flex;
            animation: slideUp 0.3s ease;
        }
        
        @keyframes slideUp {
            from { transform: translateY(30px); opacity: 0; }
            to { transform: translateY(0); opacity: 1; }
        }
        
        .back-to-top:hover {
            transform: translateY(-5px) scale(1.1);
            box-shadow: 0 20px 50px rgba(79, 70, 229, 0.6);
        }
        
        /* ===== HIDDEN SECTIONS ===== */
        .hidden-section {
            display: none;
        }
        
        .hidden-section.active {
            display: block;
            animation: fadeIn 0.5s ease-out;
        }
        
        /* ===== RESPONSIVE DESIGN ===== */
        @media (max-width: 1200px) {
            .hero-title {
                font-size: 3.2rem;
            }
        }
        
        @media (max-width: 992px) {
            .hero-section {
                padding: 160px 0 80px;
                clip-path: polygon(0 0, 100% 0, 100% 95%, 0% 100%);
            }
            
            .hero-title {
                font-size: 2.8rem;
            }
            
            .step-indicator::before {
                display: none;
            }
            
            .step {
                margin-bottom: 1rem;
            }
            
            .step-number {
                width: 50px;
                height: 50px;
                font-size: 1.2rem;
            }
        }
        
        @media (max-width: 768px) {
            .hero-title {
                font-size: 2.3rem;
            }
            
            .hero-subtitle {
                font-size: 1.1rem;
            }
            
            .feature-card,
            .tool-card,
            .step-card {
                padding: 1.5rem;
            }
            
            .options-grid {
                grid-template-columns: 1fr;
            }
            
            .preview-item {
                width: 100%;
            }
            
            .control-buttons {
                justify-content: center;
            }
            
            .back-to-top {
                width: 50px;
                height: 50px;
                bottom: 20px;
                right: 20px;
                font-size: 1.2rem;
            }
        }
        
        @media (max-width: 576px) {
            .hero-section {
                padding: 140px 0 60px;
            }
            
            .hero-title {
                font-size: 2rem;
            }
            
            .upload-area {
                padding: 2rem 1rem;
            }
            
            .upload-icon {
                width: 70px;
                height: 70px;
                font-size: 2rem;
            }
            
            .brand-badge {
                padding: 0.3rem 0.8rem;
                font-size: 0.8rem;
            }
        }
        
        /* ===== UTILITY CLASSES ===== */
        .gradient-text {
            background: var(--primary-gradient);
            -webkit-background-clip: text;
            -webkit-text-fill-color: transparent;
            background-clip: text;
        }
        
        .glow-text {
            text-shadow: 0 0 20px rgba(79, 70, 229, 0.3);
        }
        
        .shadow-soft {
            box-shadow: var(--shadow-sm);
        }
        
        .transition-all {
            transition: var(--transition);
        }
        
        /* ===== CUSTOM SCROLLBAR ===== */
        ::-webkit-scrollbar {
            width: 10px;
            height: 10px;
        }
        
        ::-webkit-scrollbar-track {
            background: var(--gray-200);
            border-radius: 10px;
        }
        
        ::-webkit-scrollbar-thumb {
            background: var(--primary-gradient);
            border-radius: 10px;
        }
        
        ::-webkit-scrollbar-thumb:hover {
            background: linear-gradient(135deg, #4338ca 0%, #6d28d9 100%);
        }
        
        /* ===== ACCESSIBILITY ===== */
        .sr-only {
            position: absolute;
            width: 1px;
            height: 1px;
            padding: 0;
            margin: -1px;
            overflow: hidden;
            clip: rect(0, 0, 0, 0);
            border: 0;
        }
        
        .focus-visible:focus-visible {
            outline: 3px solid var(--primary-color);
            outline-offset: 2px;
        }

        /* ===== DARK THEME OVERRIDES ===== */
        :root {
            --dark:#0f0f1a; --dark-card:#1a1a2e; --dark-border:rgba(255,255,255,0.06);
            --text-primary:#f1f1f6; --text-secondary:#a0a0b8; --text-muted:#6b6b80;
            --glass-bg:rgba(255,255,255,0.04); --glass-border:rgba(255,255,255,0.08);
            --primary-glow:rgba(108,92,231,0.25); --shadow-glow:0 8px 40px rgba(108,92,231,0.12);
        }
        body, html { background:#0f0f1a !important; color:var(--text-primary) !important; }
        body::before {
            background: radial-gradient(circle at 10% 20%,rgba(108,92,231,0.08) 0%,transparent 20%),
                        radial-gradient(circle at 90% 80%,rgba(253,121,168,0.06) 0%,transparent 20%),
                        radial-gradient(circle at 50% 50%,rgba(0,206,201,0.04) 0%,transparent 30%) !important;
        }
        h1,h2,h3,h4,h5,h6,.text-dark,.file-name,.setting-label,.accordion-button,
        .tool-name,.step-label,.feature-card h3,.step-card h4 { color:var(--text-primary) !important; }
        p,.text-muted,.tool-desc,.small,.lead,.benefit-list li,.accordion-body,
        .step-label,.feature-card p,.step-card p { color:var(--text-secondary) !important; }
        a.text-muted { color:var(--text-secondary) !important; }

        .main-nav { background:rgba(15,15,26,0.98) !important; border-bottom-color:rgba(255,255,255,0.06) !important; box-shadow:0 8px 32px rgba(0,0,0,0.3) !important; }
        .nav-scrolled { background:rgba(15,15,26,0.98) !important; box-shadow:0 10px 40px rgba(0,0,0,0.4) !important; }

        .upload-card { background:var(--dark-card) !important; border-color:var(--glass-border) !important; box-shadow:0 8px 40px rgba(0,0,0,0.3) !important; }
        .upload-card:hover { box-shadow:0 35px 90px rgba(108,92,231,0.2) !important; }
        .upload-area { background:rgba(108,92,231,0.06) !important; border-color:rgba(108,92,231,0.25) !important; }
        .upload-area:hover { background:rgba(108,92,231,0.12) !important; }
        .upload-area.dragover { background:rgba(108,92,231,0.18) !important; }
        .upload-area::before { background:linear-gradient(90deg,transparent,rgba(108,92,231,0.08),transparent) !important; }

        .file-list { background:var(--dark-card) !important; border-color:var(--glass-border) !important; }
        .file-item { background:transparent !important; border-bottom-color:var(--glass-border) !important; }
        .file-item:hover { background:rgba(255,255,255,0.04) !important; }

        .settings-panel { background:var(--dark-card) !important; border-color:var(--glass-border) !important; }
        .setting-label { color:var(--text-primary) !important; }
        .option-card { background:rgba(255,255,255,0.04) !important; border-color:var(--glass-border) !important; }
        .option-card:hover { background:rgba(108,92,231,0.08) !important; border-color:rgba(108,92,231,0.4) !important; }
        .option-card.selected { background:rgba(108,92,231,0.15) !important; border-color:var(--primary-color) !important; }
        .layout-single, .layout-grid { background:rgba(255,255,255,0.08) !important; }

        .sample-files { background:rgba(108,92,231,0.06) !important; border-color:rgba(108,92,231,0.15) !important; }
        .sample-item { background:rgba(255,255,255,0.04) !important; border-color:var(--glass-border) !important; }
        .sample-item:hover { border-color:rgba(108,92,231,0.4) !important; }
        .formats-list .format-item { background:rgba(255,255,255,0.04) !important; border-color:var(--glass-border) !important; color:var(--text-secondary) !important; }
        .formats-list .format-item:hover { color:#fff !important; }

        .feature-card { background:var(--dark-card) !important; border-color:var(--glass-border) !important; }
        .feature-card:hover { border-color:rgba(108,92,231,0.25) !important; }

        .step-card { background:var(--dark-card) !important; border-color:var(--glass-border) !important; }
        .step-card:hover { border-color:rgba(108,92,231,0.4) !important; }

        .tool-card { background:var(--dark-card) !important; border-color:transparent !important; color:var(--text-primary) !important; }
        .tool-card:hover { border-color:rgba(108,92,231,0.4) !important; color:var(--text-primary) !important; }

        .faq-section { background:#0f0f1a !important; }
        .accordion-item { background:var(--dark-card) !important; border:none !important; }
        .accordion-button { background:var(--dark-card) !important; color:var(--text-primary) !important; }
        .accordion-button:not(.collapsed) { background:rgba(108,92,231,0.12) !important; color:var(--primary-light) !important; }
        .accordion-button::after { filter:brightness(0) invert(1); }
        .accordion-body { background:rgba(255,255,255,0.02) !important; color:var(--text-secondary) !important; }

        .features-section, .tools-section { background:#0f0f1a !important; }
        .article-section { background:transparent !important; }
        .article-card { background:var(--dark-card) !important; border-color:var(--glass-border) !important; }
        .article-card h2,.article-card h4 { color:var(--text-primary) !important; }
        .article-card p { color:var(--text-secondary) !important; }

        .benefit-box { background:rgba(108,92,231,0.06) !important; border-left-color:var(--primary-color) !important; }
        .benefit-list li { color:var(--text-secondary) !important; border-bottom-color:var(--glass-border) !important; }

        .loading-overlay { background:rgba(15,15,26,0.95) !important; }
        .loading-spinner { border-color:rgba(255,255,255,0.1) !important; }
        #loadingText { color:var(--text-primary) !important; }

        .step-indicator::before { background:rgba(255,255,255,0.1) !important; }
        .step-number { background:rgba(255,255,255,0.08) !important; color:var(--text-muted) !important; border-color:var(--dark-card) !important; }
        .step-number.active { background:var(--primary-gradient) !important; color:#fff !important; }

        ::-webkit-scrollbar-track { background:rgba(255,255,255,0.05) !important; }
        ::-webkit-scrollbar-thumb { background:var(--primary-gradient) !important; }

        .bg-white { background:#0f0f1a !important; }
        .text-white { color:#fff !important; }
        .text-white-50 { color:rgba(255,255,255,0.5) !important; }
        .btn-light { background:rgba(255,255,255,0.1) !important; color:#fff !important; border-color:rgba(255,255,255,0.2) !important; }
        .btn-light:hover { background:rgba(255,255,255,0.2) !important; color:#fff !important; }
        .btn-outline-light { border-color:rgba(255,255,255,0.3) !important; color:#fff !important; }
        .btn-outline-light:hover { background:rgba(255,255,255,0.1) !important; color:#fff !important; }
        .btn-outline-primary { border-color:var(--primary-color) !important; color:var(--primary-light) !important; }
        .btn-outline-primary:hover { background:var(--primary-gradient) !important; color:#fff !important; }

        .form-check-input { background-color:rgba(255,255,255,0.08) !important; border-color:rgba(255,255,255,0.2) !important; }
        .form-check-input:checked { background-color:var(--primary-color) !important; border-color:var(--primary-color) !important; }
        .form-select { background-color:var(--dark-card) !important; color:var(--text-primary) !important; border-color:var(--glass-border) !important; }
        .form-range::-webkit-slider-thumb { background:var(--primary-color) !important; }
        .form-range::-webkit-slider-runnable-track { background:rgba(255,255,255,0.1) !important; }
        .form-range { background:transparent !important; }

        .modal-content { background:var(--dark-card) !important; color:var(--text-primary) !important; }
        .modal-header { background:rgba(15,15,26,0.95) !important; border-bottom-color:var(--glass-border) !important; }
        .modal-body { background:var(--dark-card) !important; }
        .btn-close { filter:brightness(0) invert(1); }

        .alert-info { background:rgba(108,92,231,0.1) !important; border-color:rgba(108,92,231,0.2) !important; color:var(--text-primary) !important; }
        .alert-success { background:rgba(0,184,148,0.1) !important; border-color:rgba(0,184,148,0.2) !important; color:var(--text-primary) !important; }
        .alert-danger { background:rgba(225,112,85,0.1) !important; border-color:rgba(225,112,85,0.2) !important; color:var(--text-primary) !important; }

        .progress { background:rgba(255,255,255,0.08) !important; }
        .progress-bar { background:var(--primary-gradient) !important; }

        .carousel-caption { background:rgba(15,15,26,0.85) !important; }
        .carousel-control-prev-icon, .carousel-control-next-icon { filter:brightness(0) invert(1); }

        .content-card { background:var(--dark-card) !important; border-color:var(--glass-border) !important; }

        /* Light theme - full white page except header/footer */
        #app-content[data-theme="light"],
        #app-content[data-theme="light"] body,
        #app-content[data-theme="light"] html,
        #app-content[data-theme="light"] .faq-section,
        #app-content[data-theme="light"] .features-section,
        #app-content[data-theme="light"] .tools-section,
        #app-content[data-theme="light"] .tool-section,
        #app-content[data-theme="light"] .article-section,
        #app-content[data-theme="light"] .upload-card,
        #app-content[data-theme="light"] .article-card,
        #app-content[data-theme="light"] .settings-panel,
        #app-content[data-theme="light"] .preview-section,
        #app-content[data-theme="light"] .result-card,
        #app-content[data-theme="light"] .preview-container,
        #app-content[data-theme="light"] .modal-header,
        #app-content[data-theme="light"] .modal-body,
        #app-content[data-theme="light"] .bg-white,
        #app-content[data-theme="light"] .content-card { background:#ffffff !important; }
        html[data-theme="light"] { background:#ffffff !important; }
        html[data-theme="dark"] { background:#0f0f1a !important; }

        #app-content[data-theme="light"] { --dark:#ffffff; --dark-card:#ffffff; --dark-border:rgba(0,0,0,0.08); --text-primary:#1e293b; --text-secondary:#475569; --text-muted:#94a3b8; --glass-bg:rgba(0,0,0,0.03); --glass-border:rgba(0,0,0,0.08); --primary-glow:rgba(79,70,229,0.1); --shadow-glow:0 8px 40px rgba(79,70,229,0.06); --gray-100:#f1f5f9; --gray-200:#e2e8f0; --gray-300:#cbd5e1; --gray-400:#94a3b8; --shadow-sm:0 2px 8px rgba(0,0,0,0.06); --shadow-md:0 8px 30px rgba(0,0,0,0.08); --shadow-lg:0 20px 60px rgba(0,0,0,0.1); --shadow-xl:0 25px 80px rgba(0,0,0,0.12); }
        #app-content[data-theme="light"] .file-item:hover,
        #app-content[data-theme="light"] .option-card,
        #app-content[data-theme="light"] .sample-item,
        #app-content[data-theme="light"] .formats-list .format-item { background:rgba(0,0,0,0.02) !important; }
        #app-content[data-theme="light"] .layout-single,
        #app-content[data-theme="light"] .layout-grid { background:rgba(0,0,0,0.04) !important; }
        #app-content[data-theme="light"] .accordion-body { background:#f9fafb !important; }
        #app-content[data-theme="light"] .step-number { background:rgba(0,0,0,0.04) !important; }
        #app-content[data-theme="light"] .step-indicator::before { background:rgba(0,0,0,0.06) !important; }
        #app-content[data-theme="light"] .progress { background:rgba(0,0,0,0.05) !important; }
        #app-content[data-theme="light"] .form-range::-webkit-slider-runnable-track { background:rgba(0,0,0,0.08) !important; }
        #app-content[data-theme="light"] ::-webkit-scrollbar-track { background:rgba(0,0,0,0.03) !important; }
        #app-content[data-theme="light"] .carousel-caption { background:rgba(255,255,255,0.85) !important; }
        #app-content[data-theme="light"] .carousel-control-prev-icon,
        #app-content[data-theme="light"] .carousel-control-next-icon { filter:none !important; }
        #app-content[data-theme="light"] .text-white { color:var(--text-primary) !important; }
        #app-content[data-theme="light"] .text-white-50 { color:var(--text-muted) !important; }
        #app-content[data-theme="light"] .btn-light,
        #app-content[data-theme="light"] .btn-outline-light { background:rgba(0,0,0,0.04) !important; color:var(--text-primary) !important; border-color:rgba(0,0,0,0.1) !important; }
        #app-content[data-theme="light"] .btn-light:hover,
        #app-content[data-theme="light"] .btn-outline-light:hover { background:rgba(0,0,0,0.08) !important; color:var(--text-primary) !important; }
        #app-content[data-theme="light"] .formats-list .format-item:hover { color:var(--primary-color) !important; }
        #app-content[data-theme="light"] .btn-outline-primary:hover { background:var(--primary-gradient) !important; color:#fff !important; }
        #app-content[data-theme="light"] .form-check-input { background-color:#fff !important; border-color:rgba(0,0,0,0.2) !important; }
        #app-content[data-theme="light"] .loading-overlay { background:rgba(255,255,255,0.95) !important; }
        #app-content[data-theme="light"] .loading-text { color:var(--text-primary) !important; }
        #app-content[data-theme="light"] .main-nav { background:rgba(255,255,255,0.95) !important; border-bottom-color:rgba(0,0,0,0.08) !important; box-shadow:0 8px 32px rgba(0,0,0,0.08) !important; }
        #app-content[data-theme="light"] .nav-scrolled { background:rgba(255,255,255,0.98) !important; box-shadow:0 10px 40px rgba(0,0,0,0.1) !important; }
        #floatThemeToggle{position:fixed;top:100px;right:20px;width:48px;height:48px;background:var(--dark-card);border:1px solid var(--dark-border);border-radius:50%;cursor:pointer;z-index:1000;display:flex;align-items:center;justify-content:center;color:var(--text-primary);font-size:1.2rem;box-shadow:var(--shadow-md);transition:all .3s}#floatThemeToggle:hover{background:var(--primary-color);color:#fff;border-color:var(--primary-color)}