I was unhappy how my Gitlab didn't look like my PyCharm, so...

gistfile1.js

// ==UserScript==
// @name       Gitlab + Ubuntu + Fonts
// @namespace  http://www.patrick-stegmann.de/
// @version    1.1
// @description  More beautiful code display in Gitlab
// @match      http://gitlab.cosee.biz/*
// @copyright  2014+, Patrick Stegmann
// ==/UserScript==

// Thanks from Google Fonts!
WebFontConfig = {
	google: { families: [ 'Source+Code+Pro::latin' ] }
};
(function() {
	var wf = document.createElement('script');
    wf.src = ('https:' == document.location.protocol ? 'https' : 'http') +
      '://ajax.googleapis.com/ajax/libs/webfont/1/webfont.js';
    wf.type = 'text/javascript';
    wf.async = 'true';
    var s = document.getElementsByTagName('script')[0];
    s.parentNode.insertBefore(wf, s);
})();

sheet = window.document.styleSheets[0];
sheet.insertRule('code { font-family: "Source Code Pro"; !important }', sheet.cssRules.length);
sheet.insertRule('span.hljs-keyword { color: #ed934a !important; }', sheet.cssRules.length);
sheet.insertRule('span.hljs-number { color: #519bd4 !important; }', sheet.cssRules.length);
sheet.insertRule('span.hljs-string { color: #aed257 !important }', sheet.cssRules.length);
sheet.insertRule('span.hljs-title { color: #ddd !important; font-weight: bold; !important; }', sheet.cssRules.length);