Help with xenforo website not loading correctly

[L2T]

My xenforo forum is looking like this http://prntscr.com/l5drqf I had this before and someone gave me a code that I had to put in a file but I can't find that anymore since it is to long ago, does someone know that code or how to fix it?

 

[Kuchy]

Did you recently add a SSL to your site?

If so, add this to your config.php file

$_SERVER['HTTPS'] = 'on';

You could've just searched Google. You're bound to find an answer...