You have this in your stylesheet:
function msk_load_css_fontawesome() {
if (!is_admin()) {
wp_enqueue_style( 'font-awesome', '//netdna.bootstrapcdn.com/font-awesome/4.0.3/css/font-awesome.min.css', null, '4.0.1' );
}
PHP isn’t allowed in CSS files, and is breaking the code below it.
If you remove the above, it should work for you.