html - Floating element with 100% height -

html - Floating element with 100% height -

i have element (represented aside) need span total height of page. however, height appearing ineffective "height 100%".

here fiddle: http://jsfiddle.net/h18ctmfq/

aside{ width:300px; float:left; background-color:#808080; height:100%; }

add this

html { height: 100%; }

jsiddle demo

html css height