header {
    font-family: Arial, sans-serif;
    margin: 0 auto;
    padding: 20px 40px;
    background-color: #f9f9f9;
    width: 100%;
}

header h2 {
    color: #333;
    border-bottom: 2px solid #333;
    padding-bottom: 10px;
    width: 15%;
}

@media (max-width: 768px) {
    header {
        padding: 0px 40px;
    }
    
    header h2 {
        color: #333;
        border-bottom: 2px solid #333;
        padding-bottom: 5px;
        width: 40%;
    }
}