html - Square DIV where height is equal to viewport

Question

I need to create a DIV where width=height, and height=100% of the viewport (which, obviously, is variable).

In other words, a perfectly square DIV that calculates it's dimensions based on the height of the viewport. Elements within that DIV will take their dimensions as percentages of the parent-DIV's height & width.

It seems to me like this should be simple to do in CSS, but I've gotten stuck with it! Any pointers would be much appreciated.

Answer 1

There is a neat trick using pure css that i stumbled upon:

#square {
width: 100%;
height: 0;
padding-bottom: 100%;
}

Hope that helps.

http://blog.brianjohnsondesign.com/2013/maintain-aspect-ratio-for-html-element-using-only-css-in-a-responsive-design/