Admin Forum:Javascript Calculator

I want to make a calculator on my wiki like the one on this page but I can't figure out how they did it. I tried copying all the related Mediawiki/Template pages to my wiki but it still doesn't work. Am I missing something?

Nconspicuous TALK

Edit: It seems this wiki is having problems with even basic codes like bloglist. Copy-pasting the pages on another wiki works just fine. It's the Miscrits wiki if you want to take a look.

Nconspicuous TALK