/* Base Styles */
        :root {
            --primary-color: #4361ee;
            --primary-dark: #3a56cc;
            --secondary-color: #6c757d;
            --success-color: #28a745;
            --danger-color: #dc3545;
            --warning-color: #ffc107;
            --info-color: #17a2b8;
            --light-color: #f8f9fa;
            --dark-color: #212529;
            --white: #ffffff;
            --gray-light: #e9ecef;
            --gray-medium: #ced4da;
            --gray-dark: #6c757d;
            --border-radius: 8px;
            --box-shadow: 0 5px 15px rgba(0, 0, 0, 0.1);
            --transition: all 0.3s cubic-bezier(0.25, 0.8, 0.25, 1);
        }

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

        body {
            font-family: 'Inter', -apple-system, BlinkMacSystemFont, 'Segoe UI', Roboto, sans-serif;
            line-height: 1.6;
            color: var(--dark-color);
            background-color: #f8fafc;
            -webkit-font-smoothing: antialiased;
        }

        .container {
            max-width: 1200px;
            margin: 0 auto;
            padding: 0 20px;
        }

        /* Header Styles */
        .header-gradient {
            background: linear-gradient(135deg, var(--primary-color) 0%, #4895ef 100%);
            color: white;
            padding: 1rem 1rem;
            border-radius: var(--border-radius);
            margin-bottom: 1rem;
            margin-top: 1rem;
            box-shadow: var(--box-shadow);
            position: relative;
            overflow: hidden;
        }

        .header-gradient::after {
            content: '';
            position: absolute;
            top: -50%;
            right: -50%;
            width: 100%;
            height: 200%;
            background: radial-gradient(circle, rgba(255,255,255,0.1) 0%, rgba(255,255,255,0) 70%);
        }

        .header-content {
            text-align: center;
            position: relative;
            z-index: 1;
        }

        .header-content h1 {
            font-size: 1.5rem;
            margin-bottom: 0.75rem;
            font-weight: 700;
            letter-spacing: -0.5px;
        }

        .header-content .subtitle {
            font-size: 1rem;
            opacity: 0.9;
            margin-bottom: 1.5rem;
            font-weight: 400;
            max-width: 700px;
            margin-left: auto;
            margin-right: auto;
        }

        .header-badge {
            display: inline-flex;
            align-items: center;
            background-color: rgba(255, 255, 255, 0.2);
            padding: 0.5rem 1.25rem;
            border-radius: 50px;
            font-size: 0.9rem;
            font-weight: 500;
            backdrop-filter: blur(5px);
            -webkit-backdrop-filter: blur(5px);
        }

        .header-badge i {
            margin-right: 0.5rem;
        }

        /* Tool Container - Side by Side Panels */
        .tool-container {
            display: flex;
            flex-wrap: wrap;
            gap: 25px;
            margin-bottom: 2.5rem;
        }

        .tool-container .panel {
            flex: 1;
            min-width: 350px;
        }

        /* Panel Styles */
        .panel {
            background-color: var(--white);
            border-radius: var(--border-radius);
            box-shadow: var(--box-shadow);
            overflow: hidden;
            transition: transform 0.3s ease, box-shadow 0.3s ease;
        }

        .panel:hover {
            transform: translateY(-3px);
            box-shadow: 0 8px 25px rgba(0, 0, 0, 0.15);
        }

        .panel-header {
            padding: 1.25rem 1.5rem;
            border-bottom: 1px solid var(--gray-light);
            display: flex;
            align-items: center;
            background-color: #f8fafc;
        }

        .panel-title {
            display: flex;
            align-items: center;
            font-size: 1.25rem;
            font-weight: 600;
            color: var(--dark-color);
        }

        .panel-title i {
            margin-right: 0.75rem;
            color: var(--primary-color);
            font-size: 1.1em;
        }

        /* Upload Panel */
        .upload-section {
            padding: 2rem 1.5rem;
            text-align: center;
        }

        .upload-option {
            border: 2px dashed var(--gray-medium);
            border-radius: var(--border-radius);
            padding: 2.5rem 1.5rem;
            cursor: pointer;
            transition: var(--transition);
            margin-bottom: 1.5rem;
            background-color: #f8fafc;
        }

        .upload-option:hover {
            border-color: var(--primary-color);
            background-color: rgba(67, 97, 238, 0.03);
            transform: translateY(-2px);
        }

        .upload-option.dragover {
            border-color: var(--primary-color);
            background-color: rgba(67, 97, 238, 0.05);
        }

        .upload-icon {
            font-size: 2.75rem;
            color: var(--primary-color);
            margin-bottom: 1.25rem;
            transition: transform 0.3s ease;
        }

        .upload-option:hover .upload-icon {
            transform: scale(1.1);
        }

        .upload-text {
            font-size: 1.25rem;
            font-weight: 600;
            margin-bottom: 0.5rem;
            color: var(--dark-color);
        }

        .upload-subtext {
            color: var(--gray-dark);
            font-size: 0.95rem;
            margin-bottom: 1rem;
        }

        #fileInput {
            display: none;
        }

        .file-requirements {
            font-size: 0.85rem;
            color: var(--gray-dark);
        }

        .file-requirements i {
            margin-right: 0.25rem;
        }

        /* File Info Container */
        .file-info-container {
            display: none;
            padding: 1.25rem 1.5rem;
            border-top: 1px solid var(--gray-light);
            background-color: #f8fafc;
        }

        .file-preview {
            display: flex;
            align-items: center;
            width: 100%;
            gap: 1rem;
        }

        .file-preview-icon {
            font-size: 2rem;
            color: var(--danger-color);
            flex-shrink: 0;
        }

        .file-preview-details {
            flex-grow: 1;
            min-width: 0;
            overflow: hidden;
        }

        .file-preview-name {
            font-weight: 600;
            margin-bottom: 0.25rem;
            white-space: nowrap;
            overflow: hidden;
            text-overflow: ellipsis;
            color: var(--dark-color);
        }

        .file-preview-meta {
            display: flex;
            gap: 1.25rem;
            font-size: 0.85rem;
            color: var(--gray-dark);
            flex-wrap: wrap;
        }

        .file-preview-meta span {
            display: flex;
            align-items: center;
        }

        .file-preview-meta i {
            margin-right: 0.35rem;
            font-size: 0.9em;
        }

        /* Compression Options */
        .compression-options {
            padding: 1.5rem;
        }

        .compression-levels {
            display: flex;
            flex-direction: column;
            gap: 1rem;
            margin-bottom: 2rem;
        }

        .compression-option {
            display: flex;
            align-items: center;
            padding: 1rem;
            border: 1px solid var(--gray-light);
            border-radius: var(--border-radius);
            cursor: pointer;
            transition: var(--transition);
        }

        .compression-option:hover {
            border-color: var(--primary-color);
            background-color: rgba(67, 97, 238, 0.03);
        }

        .compression-option.active {
            border-color: var(--primary-color);
            background-color: rgba(67, 97, 238, 0.1);
        }

        .compression-option input {
            margin-right: 1rem;
        }

        .compression-details {
            flex-grow: 1;
        }

        .compression-name {
            font-weight: 600;
            margin-bottom: 0.25rem;
            color: var(--dark-color);
        }

        .compression-description {
            font-size: 0.85rem;
            color: var(--gray-dark);
        }

        .compression-savings {
            font-weight: 600;
            color: var(--success-color);
            white-space: nowrap;
        }

        /* Advanced Options */
        .advanced-options {
            margin-top: 2rem;
        }

        .advanced-toggle {
            display: flex;
            align-items: center;
            margin-bottom: 1rem;
            cursor: pointer;
            user-select: none;
        }

        .advanced-toggle i {
            margin-right: 0.5rem;
            transition: transform 0.3s ease;
        }

        .advanced-toggle.active i {
            transform: rotate(90deg);
        }

        .advanced-content {
            display: none;
            padding: 1rem;
            border: 1px solid var(--gray-light);
            border-radius: var(--border-radius);
            background-color: #f8fafc;
        }

        .advanced-content.active {
            display: block;
        }

        .form-group {
            margin-bottom: 1.5rem;
        }

        .form-group label {
            display: block;
            margin-bottom: 0.75rem;
            font-weight: 500;
            color: var(--dark-color);
            font-size: 0.95rem;
        }

        .form-group label i {
            margin-right: 0.5rem;
            color: var(--primary-color);
            width: 20px;
            text-align: center;
            font-size: 1.05em;
        }

        .custom-range {
            width: 100%;
            height: 8px;
            -webkit-appearance: none;
            background: var(--gray-light);
            border-radius: 4px;
            outline: none;
            margin-top: 0.5rem;
            margin-bottom: 0.75rem;
        }

        .custom-range::-webkit-slider-thumb {
            -webkit-appearance: none;
            width: 20px;
            height: 20px;
            background: var(--primary-color);
            border-radius: 50%;
            cursor: pointer;
            transition: transform 0.2s ease;
        }

        .custom-range::-webkit-slider-thumb:hover {
            transform: scale(1.1);
        }

        .range-labels {
            display: flex;
            justify-content: space-between;
            font-size: 0.8rem;
            color: var(--gray-dark);
        }

        /* Panel Footer */
        .panel-footer {
            padding: 1.25rem 1.5rem;
            border-top: 1px solid var(--gray-light);
            display: flex;
            justify-content: space-between;
            background-color: #f8fafc;
        }

        /* Button Styles */
        .btn {
            display: inline-flex;
            align-items: center;
            justify-content: center;
            padding: 0.85rem 1.5rem;
            border: none;
            border-radius: var(--border-radius);
            font-size: 0.95rem;
            font-weight: 500;
            cursor: pointer;
            transition: var(--transition);
            line-height: 1;
        }

        .btn i {
            margin-right: 0.5rem;
            font-size: 1em;
        }

        .btn-primary {
            background-color: var(--primary-color);
            color: white;
            box-shadow: 0 4px 12px rgba(67, 97, 238, 0.25);
        }

        .btn-primary:hover {
            background-color: var(--primary-dark);
            transform: translateY(-2px);
            box-shadow: 0 6px 16px rgba(67, 97, 238, 0.3);
        }

        .btn-primary:active {
            transform: translateY(0);
        }

        .btn-primary:disabled {
            background-color: var(--gray-medium);
            cursor: not-allowed;
            transform: none;
            box-shadow: none;
        }

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

        .btn-secondary:hover {
            background-color: #5a6268;
            transform: translateY(-2px);
        }

        .btn-reset {
            background-color: var(--gray-light);
            color: var(--dark-color);
        }

        .btn-reset:hover {
            background-color: var(--gray-medium);
            transform: translateY(-2px);
        }

        .btn-change-file {
            background-color: transparent;
            color: var(--primary-color);
            border: 1px solid var(--primary-color);
            padding: 0.6rem 1.25rem;
            font-size: 0.9rem;
        }

        .btn-change-file:hover {
            background-color: rgba(67, 97, 238, 0.1);
            transform: translateY(-2px);
        }

        /* Results Section */
        .results-container {
            display: none;
            margin-bottom: 3rem;
        }

        .results-header {
            display: flex;
            justify-content: space-between;
            align-items: center;
            padding: 1.25rem 1.5rem;
            background-color: var(--white);
            border-radius: var(--border-radius) var(--border-radius) 0 0;
            box-shadow: var(--box-shadow);
        }

        .results-title {
            display: flex;
            align-items: center;
            font-size: 1.25rem;
            font-weight: 600;
        }

        .results-title i {
            margin-right: 0.75rem;
            color: var(--success-color);
        }

        .results-badge {
            background-color: rgba(40, 167, 69, 0.1);
            color: var(--success-color);
            padding: 0.5rem 1.25rem;
            border-radius: 50px;
            font-size: 0.9rem;
            font-weight: 500;
        }

        .results-content {
            background-color: var(--white);
            padding: 1.5rem;
            border-radius: 0 0 var(--border-radius) var(--border-radius);
            box-shadow: var(--box-shadow);
        }

        .results-stats {
            display: flex;
            flex-wrap: wrap;
            gap: 1.5rem;
            margin-bottom: 2rem;
        }

        .stat-card {
            flex: 1;
            min-width: 200px;
            padding: 1.5rem;
            border-radius: var(--border-radius);
            background-color: #f8fafc;
            text-align: center;
        }

        .stat-value {
            font-size: 2rem;
            font-weight: 700;
            color: var(--primary-color);
            margin-bottom: 0.5rem;
        }

        .stat-label {
            font-size: 0.9rem;
            color: var(--gray-dark);
        }

        .savings-badge {
            display: inline-block;
            padding: 0.25rem 0.75rem;
            border-radius: 50px;
            background-color: rgba(40, 167, 69, 0.1);
            color: var(--success-color);
            font-weight: 600;
            font-size: 0.85rem;
            margin-top: 0.5rem;
        }

        .results-actions {
            display: flex;
            flex-wrap: wrap;
            gap: 1rem;
            margin-top: 2rem;
        }

        /* Loading Overlay */
        .loading-overlay {
            position: fixed;
            top: 0;
            left: 0;
            width: 100%;
            height: 100%;
            background-color: rgba(255, 255, 255, 0.95);
            display: none;
            justify-content: center;
            align-items: center;
            z-index: 9999;
            backdrop-filter: blur(3px);
            -webkit-backdrop-filter: blur(3px);
        }

        .loading-content {
            text-align: center;
            max-width: 300px;
            padding: 2rem;
            background-color: white;
            border-radius: var(--border-radius);
            box-shadow: var(--box-shadow);
        }

        .spinner {
            width: 80px;
            height: 80px;
            margin: 0 auto 1.5rem;
            position: relative;
        }

        .double-bounce1, .double-bounce2 {
            width: 100%;
            height: 100%;
            border-radius: 50%;
            background-color: var(--primary-color);
            opacity: 0.6;
            position: absolute;
            top: 0;
            left: 0;
            animation: sk-bounce 2.0s infinite ease-in-out;
        }

        .double-bounce2 {
            animation-delay: -1.0s;
        }

        @keyframes sk-bounce {
            0%, 100% { 
                transform: scale(0.0);
            } 50% { 
                transform: scale(1.0);
            }
        }

        .loading-text {
            font-size: 1.25rem;
            font-weight: 500;
            margin-bottom: 1rem;
            color: var(--dark-color);
        }

        .loading-progress {
            font-size: 1rem;
            color: var(--gray-dark);
            font-weight: 500;
        }

        /* Toast Notifications */
        .toast-container {
            position: fixed;
            bottom: 25px;
            right: 25px;
            z-index: 1000;
            display: flex;
            flex-direction: column;
            gap: 12px;
        }

        .toast {
            padding: 1rem 1.5rem;
            border-radius: var(--border-radius);
            background-color: var(--white);
            box-shadow: var(--box-shadow);
            display: flex;
            align-items: center;
            max-width: 350px;
            opacity: 0;
            transform: translateY(20px);
            transition: all 0.3s cubic-bezier(0.68, -0.55, 0.265, 1.55);
            border-left: 4px solid transparent;
        }

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

        .toast i {
            margin-right: 0.75rem;
            font-size: 1.3rem;
        }

        .toast.success {
            border-left-color: var(--success-color);
        }

        .toast.success i {
            color: var(--success-color);
        }

        .toast.error {
            border-left-color: var(--danger-color);
        }

        .toast.error i {
            color: var(--danger-color);
        }

        .toast-close {
            margin-left: 1rem;
            background: none;
            border: none;
            font-size: 1.3rem;
            cursor: pointer;
            color: var(--gray-dark);
            opacity: 0.7;
            transition: var(--transition);
            line-height: 1;
        }

        .toast-close:hover {
            opacity: 1;
            color: var(--dark-color);
        }

        /* Responsive Styles */
        @media (max-width: 992px) {
            .tool-container {
                flex-direction: column;
            }
            
            .tool-container .panel {
                min-width: 100%;
            }
        }

        @media (max-width: 768px) {
            .header-content h1 {
                font-size: 1.5rem;
            }
            
            .header-content .subtitle {
                font-size: 1rem;
            }
            
            .results-stats {
                flex-direction: column;
            }
            
            .stat-card {
                min-width: 100%;
            }
            
            .panel-header, .panel-footer {
                padding: 1rem 1.25rem;
            }
        }

        @media (max-width: 576px) {
            .container {
                padding: 0 15px;
            }
            
            .header-gradient {
                padding: 1rem 1rem;
            }
            
            .header-content h1 {
                font-size: 1.5rem;
            }
            
            .results-actions {
                flex-direction: column;
            }
        }

        /* Animation for file upload */
        @keyframes pulse {
            0% { transform: scale(1); }
            50% { transform: scale(1.05); }
            100% { transform: scale(1); }
        }

        .uploading-animation {
            animation: pulse 1.5s infinite;
        }

        /* Article Section */
        .article-container {
            background-color: var(--white);
            border-radius: var(--border-radius);
            padding: 2rem;
            margin-bottom: 3rem;
            box-shadow: var(--box-shadow);
            max-width: 1200px;
             margin: 3rem auto; /* auto horizontally centers the container */
        }
        
        .article-title {
            font-size: 1.5rem;
            color: var(--primary);
            margin-bottom: 1.5rem;
            display: flex;
            align-items: center;
            gap: 10px;
        }

        .article-content {
            line-height: 1.8;
            color: var(--dark-color);
        }

        .article-content h2 {
            font-size: 1.5rem;
            margin: 2rem 0 1rem;
            color: var(--primary-color);
        }

        .article-content p {
            margin-bottom: 1.2rem;
        }

        .article-content ul {
            margin-bottom: 1.2rem;
            padding-left: 1.5rem;
        }

        .article-content li {
            margin-bottom: 0.5rem;
        }