body {
    margin: 0px;
}

#header {
    text-align: center;
    border: 1px solid black;
    position: fixed;
    top: 0px; 
    width: 100%;
    background-color: yellow;
}

#menu {
    border: 1px solid black;
    float: left;
    width: 15%; 
    margin-top: 5em;
    padding-right: 0.5em;
}

#content {
    border: 1px solid black;
    float: right;
    width: 80%;
    margin-top: 5em;
    margin-bottom: 1em;
    padding: 1em;
}

#footer {
    text-align: center;
    border: 1px solid black;
    clear: both;
}

p {
    column-count: 3;
    column-rule: 1px solid black;
}