Literally a CSS (and less) file to allow you to turn a simple div into a shiny button you'd find on you grandmothers favourite cardigan.
Just download this repo, copy the css file into your project, and link it like any other css file.
If you're using less preprocessing you can using the mixin in the button.less file.
Just copy the less file into your work folder and @import it into your main less file. To change the colour either change the colour referenced next to @button-colour or duplicate the whole class and create as many colours as you like.