* {
            margin: 0;
            padding: 0;
            box-sizing: border-box;
        }
        
        body {
            font-family: Arial, sans-serif;
            line-height: 1;
            color: #333;
            background-color: #f5f5f5;
        }
        
        .container {
            max-width: 1200px;
            margin: 0 auto;
            padding: 0 20px;
        }

        header {
            background-color: #2c3e50;
            color: white;
            /* padding: 1rem 0; */
            box-shadow: 0 2px 5px rgba(0,0,0,0.1);
            padding-bottom: 0;
        }
        
        .header-content {
            display: flex;
            justify-content: space-between;
            align-items: center;
            padding-top: 20px;
            padding-bottom: 20px;
        }
        
        .logo {
            font-size: 1.5rem;
            font-weight: bold;
            color: #3498db;
        }
        
        nav ul {
            display: flex;
            list-style: none;
            gap: 2rem;
            /* background-color: #34495e; */
            height: 33px;
            align-items: center;
            background: linear-gradient(135deg, #3498db, #2c3e50);
            padding-left: 2rem;
        }
        
        nav  a {
            color: white;
            text-decoration: none;
            padding: 0.5rem 1rem;
            border-radius: 4px;
            transition: background-color 0.3s;
        }
        
        nav a:hover {
            background-color: #34495e;
        }
        
        .hero {
            background: linear-gradient(135deg, #3498db, #2c3e50);
            color: white;
            padding: 2rem 0;
            text-align: center;
            margin-bottom: 2rem;
        }
        
        .hero p {
            font-size: 1.2rem;
            max-width: 600px;
            margin: 0 auto;
        }
        
        .btn {
            display: inline-block;
            font-size: 1.0rem;
            background-color:  #3498db;
            color: white;
            padding: 0.3rem 0.5rem;
            text-decoration: none;
            border-radius: 5px;
            /* font-weight: bold; */
            transition: background-color 0.3s;
        }
        
        .btn:hover {
            background-color: #c0392b;
        }
        
        .btn-secondary {
            background-color: #3498db;
        }
        
        .btn-secondary:hover {
            background-color: #2980b9;
        }
        
        .materials {
            margin-bottom: 3rem;
        }
        
        .materials h2 {
            text-align: center;
            margin-bottom: 2rem;
            color: #2c3e50;
        }
        
        .materials-grid {
            display: grid;
            grid-template-columns: repeat(auto-fit, minmax(350px, 1fr));
            gap: 2rem;
        }
        
        .material-card {
            background: white;
            border-radius: 8px;
            overflow: hidden;
            box-shadow: 0 2px 10px rgba(0,0,0,0.1);
            transition: transform 0.3s;
        }
        
        .material-card:hover {
            transform: translateY(-5px);
        }
        
        .material-content {
            padding: 1.5rem;
        }

        .material-description {
            color: #666;
            margin: 0.5rem 0;
            flex-grow: 1;
            line-height: 1.6;
        }
        
        .level {
            display: inline-block;
            padding: 0.3rem 0.8rem;
            border-radius: 20px;
            font-size: 0.8rem;
            font-weight: bold;
            margin-bottom: 1rem;
        }
        
        
        
        footer {
            background-color: #2c3e50;
            color: white;
            text-align: center;
            padding: 1.5rem 0;
            margin-top: 2rem;
        }

        navfooter  a {
            color: rgb(207, 207, 207);
            text-decoration: none;
            padding: 0.5rem 1rem;
            border-radius: 4px;
            transition: background-color 0.3s;
        }
        
        navfooter a:hover {
            background-color: #34495e;
        }

        .footerdesc {
            color: #eeeaea;
            margin-bottom: 1rem;
        }