In addition to Virgil's response, I'd add that if you're referencing any external resources via HTTP to remove that and simply use //. For instance:
THIS:
<link href="http//fonts.googleapis.com/css?family=Source+Sans+Pro:700,400,300&subset=latin,latin-ext" rel="stylesheet" type="text/css">
Would become THIS:
<link href="//fonts.googleapis.com/css?family=Source+Sans+Pro:700,400,300&subset=latin,latin-ext" rel="stylesheet" type="text/css">