How can I add a box-shadow on one side of an element?

Question

I need to create a box-shadow on some block element, but only (for example) on its right side. The way I do it is to wrap the inner element with box-shado

Answer 1

This site helped me: https://gist.github.com/ocean90/1268328 (Note that on that site the left and right are reversed as of the date of this post... but they work as expected). They are corrected in the code below.