:root {
            --primary-color: #0066cc;
            --secondary-color: #00a0e4;
            --accent-color: #ff6b6b;
            --bg-color: #ffffff;
            --text-color: #333333;
            --card-bg: #ffffff;
            --border-color: #dddddd;
            --shadow: 0 4px 12px rgba(0, 0, 0, 0.1);
            --header-bg: linear-gradient(90deg, #0066cc 0%, #00a0e4 100%);
            --btn-primary: linear-gradient(90deg, #0066cc 0%, #00a0e4 100%);
            --btn-secondary: linear-gradient(90deg, #ff6b6b 0%, #ff8e8e 100%);
        }

        [data-theme="dark"] {
            --primary-color: #4dabf7;
            --secondary-color: #339af0;
            --accent-color: #ff8787;
            --bg-color: #121212;
            --text-color: #e9ecef;
            --card-bg: #1e1e1e;
            --border-color: #343a40;
            --shadow: 0 4px 12px rgba(0, 0, 0, 0.3);
            --header-bg: linear-gradient(90deg, #0c4a8c 0%, #0a6ebd 100%);
            --btn-primary: linear-gradient(90deg, #0c4a8c 0%, #0a6ebd 100%);
            --btn-secondary: linear-gradient(90deg, #c92a2a 0%, #e03131 100%);
        }

        * {
            margin: 0;
            padding: 0;
            box-sizing: border-box;
            font-family: 'Segoe UI', Tahoma, Geneva, Verdana, sans-serif;
            transition: background-color 0.3s, color 0.3s;
        }

        body {
            background-color: var(--bg-color);
            color: var(--text-color);
            line-height: 1.6;
        }

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

        /* Header Styles */
        header {
            background: var(--header-bg);
            color: white;
            padding: 15px 0;
            box-shadow: var(--shadow);
            border-radius: 0 0 10px 10px;
            margin-bottom: 30px;
        }

        .header-content {
            display: flex;
            justify-content: space-between;
            align-items: center;
            padding: 0 20px;
        }

        .logo {
            display: flex;
            align-items: center;
            gap: 15px;
        }

        .logo img {
            height: 50px;
            width: auto;
        }

        .logo h1 {
            font-size: 28px;
            font-weight: 700;
            letter-spacing: 0.5px;
        }

        nav ul {
            display: flex;
            list-style: none;
            gap: 25px;
            align-items: center;
        }

        nav a {
            color: white;
            text-decoration: none;
            font-weight: 500;
            font-size: 18px;
            transition: all 0.3s ease;
            padding: 5px 10px;
            border-radius: 5px;
        }

        nav a:hover {
            background-color: rgba(255, 255, 255, 0.2);
        }

        .theme-toggle {
            background: none;
            border: none;
            color: white;
            font-size: 20px;
            cursor: pointer;
            padding: 5px;
            border-radius: 50%;
            width: 40px;
            height: 40px;
            display: flex;
            align-items: center;
            justify-content: center;
        }

        .theme-toggle:hover {
            background-color: rgba(255, 255, 255, 0.2);
        }

        /* Breadcrumb */
        .breadcrumb {
            padding: 15px 0;
            background-color: var(--bg-color);
            border-bottom: 1px solid var(--border-color);
        }

        .breadcrumb .container {
            display: flex;
            align-items: center;
            gap: 10px;
        }

        .breadcrumb a {
            color: var(--primary-color);
            text-decoration: none;
            transition: color 0.3s;
        }

        .breadcrumb a:hover {
            color: var(--secondary-color);
        }

        .breadcrumb span {
            color: var(--text-color);
        }

        /* Main Layout */
        .main-layout {
            display: flex;
            gap: 30px;
            margin-bottom: 30px;
        }

        .content-section {
            flex: 1;
        }

        .sidebar-section {
            width: 300px;
        }

        /* Main Content Styles */
        .main-content {
            background-color: var(--card-bg);
            border-radius: 12px;
            padding: 25px;
            box-shadow: var(--shadow);
            margin-bottom: 30px;
        }

        .section-title {
            color: var(--primary-color);
            font-size: 28px;
            margin-bottom: 20px;
            padding-bottom: 10px;
            border-bottom: 2px solid var(--secondary-color);
        }

        .image-gallery {
            display: flex;
            flex-direction: column;
            gap: 25px;
            margin: 30px 0;
        }

        .paper-image {
            position: relative;
            border: 1px solid var(--border-color);
            border-radius: 8px;
            overflow: hidden;
            box-shadow: 0 3px 10px rgba(0, 0, 0, 0.1);
        }

        .paper-image img {
            width: 100%;
            height: auto;
            display: block;
            pointer-events: none;
            user-select: none;
        }

        .watermark {
            position: absolute;
            top: 50%;
            left: 50%;
            transform: translate(-50%, -50%) rotate(-45deg);
            font-size: clamp(40px, 10vw, 60px);
            color: rgba(0, 102, 204, 0.15);
            font-weight: bold;
            pointer-events: none;
            user-select: none;
            white-space: nowrap;
        }

        [data-theme="dark"] .watermark {
            color: rgba(77, 171, 247, 0.15);
        }

        /* Sidebar Styles */
        .sidebar {
            background-color: var(--card-bg);
            border-radius: 12px;
            padding: 20px;
            box-shadow: var(--shadow);
            margin-bottom: 30px;
        }

        .sidebar h3 {
            color: var(--primary-color);
            margin-bottom: 20px;
            padding-bottom: 10px;
            border-bottom: 2px solid var(--secondary-color);
        }

        .links-container {
            margin-bottom: 30px;
        }

        .links-container ul {
            list-style: none;
        }

        .links-container li {
            margin: 10px 0;
        }

        .links-container a {
            color: var(--text-color);
            text-decoration: none;
            font-size: 16px;
            transition: color 0.3s;
            display: block;
            padding: 8px 12px;
            border-radius: 4px;
        }

        .links-container a:hover {
            color: var(--primary-color);
            background-color: rgba(0, 102, 204, 0.1);
        }

        [data-theme="dark"] .links-container a:hover {
            background-color: rgba(77, 171, 247, 0.1);
        }

        .ad-space {
            background: var(--card-bg);
            border: 1px dashed var(--secondary-color);
            border-radius: 8px;
            padding: 15px;
            margin-bottom: 20px;
            text-align: center;
        }

        .ad-space h4 {
            color: var(--primary-color);
            margin-bottom: 10px;
        }

        .ad-container {
            min-height: 100px;
            display: flex;
            flex-direction: column;
            justify-content: center;
            align-items: center;
        }

        .ad-container p {
            margin: 5px 0;
            color: var(--text-color);
        }

        .ad-container .btn {
            padding: 8px 15px;
            font-size: 14px;
            margin-top: 10px;
        }

        /* Instructions Section */
        .instructions {
            background: linear-gradient(135deg, rgba(0, 102, 204, 0.1) 0%, rgba(0, 160, 228, 0.1) 100%);
            border-radius: 12px;
            padding: 25px;
            box-shadow: var(--shadow);
            margin-bottom: 30px;
            border: 2px solid var(--secondary-color);
        }

        [data-theme="dark"] .instructions {
            background: linear-gradient(135deg, rgba(12, 74, 140, 0.2) 0%, rgba(10, 110, 189, 0.2) 100%);
        }

        .instructions h2 {
            color: var(--primary-color);
            font-size: 26px;
            margin-bottom: 20px;
            display: flex;
            align-items: center;
            gap: 10px;
        }

        .steps {
            display: grid;
            grid-template-columns: repeat(auto-fit, minmax(250px, 1fr));
            gap: 20px;
            margin: 25px 0;
        }

        .step {
            background-color: var(--card-bg);
            padding: 20px;
            border-radius: 10px;
            box-shadow: 0 3px 10px rgba(0, 0, 0, 0.1);
            text-align: center;
        }

        .step i {
            font-size: 32px;
            color: var(--primary-color);
            margin-bottom: 15px;
        }

        .step h3 {
            color: var(--secondary-color);
            margin-bottom: 10px;
        }

        .email-note {
            background-color: var(--card-bg);
            padding: 20px;
            border-radius: 10px;
            text-align: center;
            margin-top: 20px;
            box-shadow: 0 3px 10px rgba(0, 0, 0, 0.1);
        }

        .email-note a {
            color: var(--primary-color);
            font-weight: 600;
            text-decoration: none;
        }

        .email-note a:hover {
            text-decoration: underline;
        }

        /* Button Styles */
        .button-group {
            display: flex;
            justify-content: center;
            gap: 20px;
            margin: 30px 0;
        }

        .btn {
            padding: 14px 28px;
            border: none;
            border-radius: 50px;
            font-size: 18px;
            font-weight: 600;
            cursor: pointer;
            transition: all 0.3s ease;
            display: flex;
            align-items: center;
            gap: 10px;
            box-shadow: 0 4px 8px rgba(0, 0, 0, 0.15);
        }

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

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

        .btn:hover {
            transform: translateY(-3px);
            box-shadow: 0 6px 12px rgba(0, 0, 0, 0.2);
        }

        .btn-round {
            border-radius: 50%;
            width: 60px;
            height: 60px;
            padding: 0;
            justify-content: center;
            background: rgba(0, 0, 0, 0.1);
            color: var(--text-color);
            box-shadow: 0 4px 8px rgba(0, 0, 0, 0.1);
        }

        [data-theme="dark"] .btn-round {
            background: rgba(255, 255, 255, 0.1);
        }

        .btn-round:hover {
            background: rgba(0, 0, 0, 0.2);
            transform: translateY(-3px);
        }

        [data-theme="dark"] .btn-round:hover {
            background: rgba(255, 255, 255, 0.2);
        }

        /* Footer */
        footer {
            text-align: center;
            padding: 20px;
            color: var(--primary-color);
            font-weight: 500;
            margin-top: 30px;
            border-top: 1px solid var(--border-color);
        }

        /* Responsive Design */
        @media (max-width: 1024px) {
            .main-layout {
                flex-direction: column;
            }
            
            .sidebar-section {
                width: 100%;
            }
            
            .sidebar-content {
                display: grid;
                grid-template-columns: 1fr 1fr;
                gap: 20px;
            }
        }

        @media (max-width: 768px) {
            .header-content {
                flex-direction: column;
                gap: 15px;
            }
            
            nav ul {
                gap: 15px;
                flex-wrap: wrap;
                justify-content: center;
            }
            
            .button-group {
                flex-direction: column;
                align-items: center;
            }
            
            .btn {
                width: 100%;
                justify-content: center;
            }
            
            .sidebar-content {
                grid-template-columns: 1fr;
            }
            
            .steps {
                grid-template-columns: 1fr;
            }
        }

        /* Screenshot Overlay */
        .screenshot-overlay {
            position: fixed;
            top: 0;
            left: 0;
            width: 100%;
            height: 100%;
            background: rgba(0, 0, 0, 0.95);
            color: white;
            display: flex;
            align-items: center;
            justify-content: center;
            z-index: 9999;
            font-size: 20px;
            text-align: center;
            padding: 20px;
            display: none;
        }