CSS: Responsive way to center a fluid div (without px width) while limiting the maximum width?

Question

I\'ve seen a million questions about how to center a block element and there seem to be a couple popular ways to do it, but they all rely on fixed pixels widths. Then either

Answer 1

Something like this could be it?

HTML

 

        SOMETHING
 

CSS

body{

    text-align: center;
}

.random{

    width: 60%;
    margin: auto;
    background-color: yellow;
    display:block;

}

DEMO: http://jsfiddle.net/t5Pp2/2/

Edit: adding display:block doesn't ruin the thing, so...

You can also set the margin to: margin: 0 auto 0 auto; just to be sure it centers only this way not from the top too.