With css-flexbox, you probably can. Your DIV should have flex-grow: 1 which will make it take the allowable space along the "main axis" (shared with other flex-growers) and then align-items: stretch, to pick up all available space along the "cross axis". With some nesting, you can do pretty much whatever you want except for the grid layout. Grid layout is another thing coming but barely implemented in the today's browsers.
Anyways, flex-box is not available in IE < 10. IE10 requires ms- prefix. If React makes it available everywhere (IE8+) that will be really great.
Thanks, but last I looked into this it wasn't possible for this to work for a square in a parent rectangle of arbitrary dimensions. Can you find an example that works, using jsfiddle or something similar?
Anyways, flex-box is not available in IE < 10. IE10 requires ms- prefix. If React makes it available everywhere (IE8+) that will be really great.