Center vertically a unknown height text in a unknown height div

Question

I know this is a common issue, and I\'ve already asked a similar one. But I could not find the solution this time. I am trying to vertically center a text which can have differe

Answer 1

Here's another way using display:table-cell since I don't quite understand how dystroy's answer works.

#test {
    width:100%;
    height : 400px;
    display:table;
}

#sumup {
    width : 100%;

    height : 100%;
    background-color: #123456;
    display:table-cell;
    vertical-align:middle;
}

http://jsfiddle.net/F8TtE/3/