css - Setting element height in responsive layout?

Question

Generally, what markup and CSS will create an element with a percentage-based height in a responsive design? How to build a 2 Column (Fixed - Fluid) Layout with Twitter Bootstrap? shows how to create two 100% height columns, but this breaks for heights < 100%.

Specifically, I have a sidebar div with a list of items, which may be short (empty) or long (overflow: auto). But because no parent elements have a fixed height, height: 20%; does not work. How can I give the sidebar a fluid height while maintaining a responsive design?

Answer 1

Usually having a fluid padding-bottom on the parent container solves this problem.

More information can be found here : http://www.alistapart.com/articles/creating-intrinsic-ratios-for-video/

update: on js bin http://jsbin.com/obesuk/1/

markup :

<div class="obj-wrapper">
 <div class="content">content</div>
</div>

css:

  .obj-wrapper {
    position:relative;
    width:50%;
    padding-bottom:40%;
    height:0;
    overflow:hidden;
  }
  .content {
    position:absolute;
    width:100%;
    height:100%;
    background:red;
  }