Question

When I expand comment body that is floated to right my container does not expand with it. How can I fix this?

Better explanation: http://jsfiddle.net/5fmpp/

Answer 1

Add overflow: hidden to the container so it can contain the float:

.comment
{
    width: 960px;
    margin: auto;
    margin-top: 24px;
    font-size: 14px;
    background-color: #777777;
    overflow: hidden;
}