*{
    box-sizing: border-box;
}
.header {
    background-color: rgb(255, 137, 84);
    text-align: center;
    padding: 20px;
}

.topnav {
    overflow: hidden;
    background-color: rgb(255, 137, 84);
}

.topnav a {
    float: left;
    display: block;
    color: white;
    text-align: center;
    padding: 14px 16px;
    text-decoration: none;
}

.topnav a:hover {
    background-color: lightblue;
    color: black;
}

.body {
    margin: 0;
}

.lcolumn {
    float: left;
    width: 60%;
}

.rcolumn {
    float: left;
    width: 40%;
    padding-left: 20px;
}

.row:after {
    content: "";
    display: table;
    clear: both;
}

@media screen and (max-width: 600px) {
    .lcolumn, .rcolumn
    {
        width: 100%;
    }
}