ul{
    list-style-type: none;
    margin: 0;
    padding: 0;
    overflow: hidden;
    background-color: rgb(54, 122, 157);
}

li{
    float: left;
}
li a{
    display: block;
    color: wheat;
    padding: 14px 16px;
    text-decoration: none;
    font-size: 20px;
    margin-top: 15px;
}
li a:hover{
 text-align: center;
    background-color: blueviolet;
}
header{
    text-align: center;
}