body {
    font-family: Arial, Helvetica, sans-serif;
}

.mobile-container {
    max-width: 480px;
    margin: auto;
    background-color: #555;
    height: 500px;
    color: white;
    border-radius: 10px;
}

.topnav {
    overflow: hidden;
    background-color: #333;
    position: relative;
}

    .topnav #myLinks {
        display: none;
        z-index: 1000;
    }

        .topnav #myLinks a {
            color: white;
        }

    .topnav a {
        padding: 14px 16px;
        text-decoration: none;
        font-size: 17px;
        display: block;
    }

        .topnav a.icon {
            background: black;
            display: block;
            position: absolute;
            right: 0;
            top: 0;
        }


.active {
    background-color: white;
    color: black;
}