In this article, I'm going to guide you through a concrete problem I had to solve. Eventually, we'll see how to use percentage values in the background-position CSS property and how it solves a lot of tough issues.
Equal height columns have been a need of web designers forever. If all the columns share the same background, equal height is irrelevant because you can set that background on a parent element. But if one or more columns need to have their own background, it becomes very important to the visual integrity of the design.
T. Rocktäschel, S. Singh, and S. Riedel. NAACL HLT 2015, The 2015 Conference of the North American Chapter of the Association for Computational Linguistics: Human Language Technologies, Denver, Colorado, USA, May 31 - June 5, 2015, page 1119--1129. (2015)