One really frustrating thing about CSS is its lack of a way to make things 100% high. You’ll notice this especially with sidebars. If there is not enough content to fill the sidebar, it falls short and looks ugly. Luckily, there are workarounds.

Requirements for our 100% height sidebar techniques:

• No images
• No unsemantic elements
• Support for IE8

The display table method

This works like a table layout, but without the table. We can set 100% height to all the elements. Check the commented code under the HTML and CSS tabs.

You can strip out either one of the sidebars and it still works.

The pseudo elements method

This is a bit more "hacky," but it works great. You just position the sidebar pseudo-elements with position: fixed. The downside to this technique is that you can't animate the sidebars (if you need to get the sidebars out of the way by toggling their visibility). See the commented code under the CSS and HTML tabs.

One day the flexbox method will have enough browser support for us to use it. Meanwhile, we have to use these.