html,
body {
    overflow-x: hidden;
    padding: 0;
    margin: 0;
    widows: 100%;
}

main {
    height: 90vh;
    overflow: auto;
    width: 75%;
}

p,
li {
    text-align: justify;
}

footer {
    background: #000;
    position: fixed;
    bottom: 0;
    width: 100%;
    padding: 5px;
}

header {
    font-weight: bold;
    font-size: 24px;
    margin-top: 30px;
    margin-bottom: 15px;
}

pre {
    background: #ddd;
    padding: 20px 0;
    font-size: 14px;
    padding-left: 20px;
    color: rgb(0, 2, 0);
}

a {
    display: block;
    border-top: 1px solid #000;
    margin-left: 15px;
    color: black;
}

a:hover {
    background: #ddd;
    color: black
}

nav{
    border-right: 1px solid black;
    height: 90vh;
    overflow: auto;
    width: 25%;
}

@media(max-width: 800px) {
    nav{
        width: 100%;
    }
    main{
        width: 100%;
    }
}