.half.left {
    float: left;
    max-width: 540px;
}

.half.right {
    float: right;
    max-width: 508px;
}

section {
    clear: both;
    min-height: 1%;
}

section:after {
    content: ".";
    display: block;
    height: 0;
    clear: both;
    visibility: hidden;
}