* {
            margin: 0;
            padding: 0;
            box-sizing: border-box;
            font-family: 'Segoe UI', Tahoma, Geneva, Verdana, sans-serif;
        }
        
        :root {
            --primary: #3498db;
            --secondary: #2c3e50;
            --accent: #e74c3c;
            --light: #f9f9f9;
            --dark: #2c3e50;
            --success: #2ecc71;
            --warning: #f39c12;
        }
        
        body {
            background-color: #f5f7fa;
            color: #333;
            line-height: 1.6;
        }
        
        header {
            background: linear-gradient(to right, var(--secondary), var(--primary));
            color: white;
            padding: 1.5rem 0;
            box-shadow: 0 4px 12px rgba(0, 0, 0, 0.1);
        }
        
        .container {
            width: 100%;
            max-width: 1200px;
            margin: auto;
            padding: 0 10px;
            align-items: center;
            border: #2ecc71;
            border-color: #3498db;
        }
        
        .header-content {
            display: flex;
            justify-content: space-between;
            align-items: center;
            flex-wrap: wrap;
        }

        .hero {
            background-color: rgb(255, 255, 255);
            padding: 1rem 0;
            text-align: center;
            margin-bottom: 1rem;
            align-items: center;
            margin: auto;
            border-radius: 0 0 10px 10px;
            box-shadow: 0 4px 6px rgba(0, 0, 0, 0.05);
        }
        
        .hero h2 {
            color: var(--secondary);
            margin-bottom: 1rem;
            font-size: 2.2rem;
        }
        
        .hero p {
            color: #666;
            max-width: 800px;
            margin: 0 auto 1.5rem;
        }
        
        .classes-grid {
            display: grid;
            grid-template-columns: repeat(auto-fill, minmax(250px, 1fr));
            gap: 10px;
            margin-bottom: 1rem;
        }
        
        .class-card {
            background-color: white;
            border-radius: 10px;
            overflow: hidden;
            box-shadow: 0 6px 10px rgba(0, 0, 0, 0.08);
            transition: transform 0.3s ease, box-shadow 0.3s ease;
        }
        
        .class-card:hover {
            transform: translateY(-5px);
            box-shadow: 0 12px 20px rgba(0, 0, 0, 0.1);
        }
        
        .class-header {
            background: linear-gradient(to right, var(--primary), var(--secondary));
            color: white;
            padding: .25rem;
            text-align: center;
        }
        
        .class-header h3 {
            font-size: 1.5rem;
            margin-bottom: 0.5rem;
        }
        
        .class-body {
            padding: 1rem;
        }
        
        .class-body h4 {
            color: var(--secondary);
            margin-bottom: 1rem;
            padding-bottom: 0.5rem;
            border-bottom: 1px solid #eee;
        }
        
        .books-list {
            list-style-type: var(--dark);
            margin-bottom: 1.5rem;
        }
        
        .books-list li {
            padding: 8px 0;
            border-bottom: 1px dashed #eee;
            display: flex;
            align-items: center;
        }
        
        .books-list li i {
            color: var(--success);
            margin-right: 10px;
        }
        
        .btn {
            display: inline-block;
            background-color: var(--primary);
            color: white;
            padding: 10px 20px;
            border-radius: 5px;
            text-decoration: none;
            font-weight: 600;
            transition: background-color 0.3s ease;
            border: none;
            cursor: pointer;
            text-align: center;
        }
        
        .btn:hover {
            background-color: #2980b9;
        }
        
        .btn-block {
            display: block;
            width: 100%;
        }
        
        .seo-content {
            background-color: white;
            padding: 2rem;
            border-radius: 10px;
            margin-bottom: 2rem;
            box-shadow: 0 4px 6px rgba(0, 0, 0, 0.05);
        }
        
        .seo-content h3 {
            color: var(--secondary);
            margin-bottom: 1rem;
            font-size: 1.5rem;
        }
        
        .seo-content p {
            margin-bottom: 1rem;
            color: #555;
        }
        
        .subject-links {
            display: grid;
            grid-template-columns: repeat(auto-fill, minmax(200px, 1fr));
            gap: 15px;
            margin-top: 1.5rem;
        }
        
        .subject-link {
            display: flex;
            align-items: center;
            padding: 15px;
            background-color: #f8f9fa;
            border-radius: 8px;
            text-decoration: none;
            color: var(--secondary);
            font-weight: 600;
            transition: all 0.3s ease;
            border-left: 4px solid var(--primary);
        }
        
        .subject-link:hover {
            background-color: #e9f7fe;
            transform: translateX(5px);
        }
        
        .subject-link i {
            margin-right: 10px;
            font-size: 1.2rem;
            color: var(--primary);
        }
        
        footer {
            background-color: var(--secondary);
            color: white;
            padding: 2rem 0;
            text-align: center;
            margin-top: 3rem;
        }
        
        .footer-content {
            display: flex;
            flex-direction: column;
            align-items: center;
        }
        
        .footer-links {
            display: flex;
            margin: 1.5rem 0;
            flex-wrap: wrap;
            justify-content: center;
            gap: 20px;
        }
        
        .footer-links a {
            color: #ddd;
            text-decoration: none;
            transition: color 0.3s ease;
        }
        
        .footer-links a:hover {
            color: white;
        }
        
        .copyright {
            color: #aaa;
            font-size: 0.9rem;
            margin-top: 1rem;
        }
        
        /* Subject Page Styles */
        .subject-header {
            background: linear-gradient(to right, #8e44ad, #3498db);
            color: white;
            padding: 2rem 0;
            margin-bottom: 2rem;
            border-radius: 0 0 10px 10px;
        }
        
        .subject-header h1 {
            font-size: 2.2rem;
            margin-bottom: 0.5rem;
        }
        
        .subject-info {
            display: flex;
            justify-content: space-between;
            align-items: center;
            flex-wrap: wrap;
            margin-bottom: 1.5rem;
        }
        
        .test-grid {
            display: grid;
            grid-template-columns: repeat(auto-fill, minmax(300px, 1fr));
            gap: 25px;
            margin-bottom: 3rem;
        }
        
        .test-card {
            background-color: white;
            border-radius: 10px;
            overflow: hidden;
            box-shadow: 0 6px 15px rgba(0, 0, 0, 0.08);
            transition: transform 0.3s ease;
        }
        
        .test-card:hover {
            transform: translateY(-5px);
        }
        
        .test-card-header {
            background-color: var(--primary);
            color: white;
            padding: 1.2rem;
        }
        
        .test-card-body {
            padding: 1.5rem;
        }
        
        .test-card-footer {
            padding: 1rem 1.5rem;
            background-color: #f8f9fa;
            border-top: 1px solid #eee;
        }
        
        .back-link {
            display: inline-flex;
            align-items: center;
            color: var(--primary);
            text-decoration: none;
            font-weight: 600;
            margin-bottom: 1.5rem;
        }
        
        .back-link i {
            margin-right: 8px;
        }
        
        @media (max-width: 768px) {
            .header-content {
                flex-direction: column;
                text-align: center;
            }
            
            nav ul {
                margin-top: 1rem;
                justify-content: center;
            }
            
            nav ul li {
                margin: 0 10px;
            }
            
            .hero h2 {
                font-size: 1.8rem;
            }
            
            .subject-links {
                grid-template-columns: repeat(2, 1fr);
            }
        }
        
        @media (max-width: 480px) {
            .classes-grid {
                grid-template-columns: 1fr;
            }
            
            .subject-links {
                grid-template-columns: 1fr;
            }
            
            .test-grid {
                grid-template-columns: 1fr;
            }
        }

        .books-list {
                list-style: none;
                padding-left: 0;
                    }

        .books-list li {
                position: relative;
                padding-left: 22px;
                    }

        .books-list li::before {
                content: "•";
                position: absolute;
                left: 0;
                color: #2ecc71; 
                font-size: 1.3rem;
                }