a {
    text-decoration: none;
    color: seagreen;
}
a:hover {
    text-decoration: underline;
}
a:visited {
    color: darkorchid;
}
a:active {
    color: red;
}
body {
    background-color: black;
    color: white;
}
h1 {
    text-align: center;
}
h2 {
    text-align: center;
}
h3 {
    text-align: center;
}
h4 {
    text-align: center;
}
h5 {
    text-align: center;
}
h6 {
    text-align: center;
}