:heading
{
    text-align: center;
    color: white;
    padding: 0.3em 0.5em;
    margin: 1em 0;
    border-radius: 10px;
}
/*:heading(4n + 1)*/
:heading(1, 5) {
    background-color: rgb(1, 96, 91);
    text-shadow: 5px 5px 10px wheat;
}

/*:heading(even)*/
:heading(2, 4, 6) {
 font-style:italic;
 background-color:purple
}

:heading(3){
    background-color: darkblue;
    text-decoration: underline;
}