Yeah, if you enqueue your style sheets (which you’re supposed to) they won’t get called until you do < ?php wp_head(); ?>. However, try checking functions.php if you can’t find it anywhere in the header.php. Last place I can think of would possibly be footer.php.
I searched all of my theme’s files (with a searching program) and there was no ‘style-red.css’ text. I don’t asked where is ‘style-red.css’ text. (I know a stylesheet should be in the header.php, footer.php or functions.php). I want to know where is its request, when there is no style-red.css text in my theme (and plugin) files.
I could remove that request by removing < ?php wp_head(); ?> code. But this made me that problem and that I don’t know how to solve that.