body {
    background-color: yellow;
}
h1 {
    color: blue;
    font-family: arial;
    font-size: 150%;
    text-align: center;}
h2 {
    color: blue;
    font-family: arial;
    font-size: 120%;
    text-align: center;}
h3 {
    color: blue;
    font-family: arial;
    font-size: 100%;
    text-align: center;}
p {
    color: black;
    font-family: arial;
    font-size: 100%;
    text-align: left;}
ul {
    color: black;
    font-family: arial;
    font-size: 100%;
    text-align: left;}