body {
    background-color: yellow;
}

h1 {
    color: red;
    text-align: center;
}

div h1 {
    color: black;
}

div {
    border: 2px solid;
    background-color: rgb(145, 247, 50);
    border-radius: 10px;
    /*margin-top: 10px;
    margin-bottom: 20px;
    margin-left: 50px;
    margin-right: 50px;*/
    margin: 10px 50px 10px 50px;
    text-align: center;
    padding: 20px 10px 20px 10px;
}

.even {
    background-color: rgb(55, 236, 221);
}

h2 {
    text-align: center;
    color: rgb(1, 15, 3);
    text-decoration: underline;
}

h3 {
    color: red;
    animation: flash 1s infinite;
}

body {
    font-weight: bold;
    font-size: 22px;
    border: 10px double;
}

.return-link {
    text-indent: -20px;
    display: block;
    margin: 20px;
    font-size: 10px;
    text-decoration: underline;
}

nav {
    text-align: center;
    border: 2px solid black;
    padding: 10px;
    border-radius: 10px;
    margin: 10px 50px 10px 50px;
}

a {
    margin-left: 30px;
    margin-right: 30px;
    text-decoration: none;
}