How to load CSS within WordPress Admin

There may come a time when you need to make some changes to the way in which the WordPress Dashboard looks, maybe you want a specific style of button, maybe you want to change the colours of some of the elements on the page or maybe you want to hide some unused Meta Boxes within the dashboard? Whatever you need this snippet for here’s how to do it, simply add the code below to your functions file and add the relevant CSS within your admin.css file.