@media only screen and (max-width: 550px) {

    nav {
        margin:auto;
        position:relative;
        width:350px;
        height:300px;
        padding:20px;
    }

    body > h2:nth-child(1) {
        margin-top:70px;
    }

    .config {
        margin-bottom:40px;
    }

    .config > ul {
        width:350px;
        margin:0 auto;
        list-style:none;
        border:double;
        border-color:lightblue;
        padding:10px;
    }

    .config > ul >li {
        font-size:20px;
        color:rgba(0, 128, 255, 0.7);
        font-weight:bold;
        margin-bottom:5px;
    }

    .selectOpt > ul {
        text-align:center;
        position:absolute;
        left:0px;
    }

    .selectOpt > ul > li {
        list-style:none;
        font-size:20px;
        width:300px;
        padding:10px;
        text-align:center;
        background-color:rgb(102, 102, 102);
        color:black;
        border-radius:20px;
        margin-bottom:20px;
    }
    .selectOpt a {
        color:black;
        text-decoration:none;
    }

    .selectOpt > ul > li:hover {
        color:rgb(64, 64, 64);
        font-weight:bold;
    }
}