The normal way of styling Module Headers is to add a Module Class Suffix in
Extensions > Modules > YourModule
and then pick it up in the template css file using a selector like moduletable-moduleclasssuffix. But what if you want to do more? What if you want a module header where the H3 color is gray, but the first word is blue? Or the last word is blue?
This article will show you how to modify h3 titles using Joomla's template overrides with module chrome and a bit help from the preg_replace function.