Oh check this for scary. ![Cheesy :D](https://www.elkarte.net/community/smileys/default/cheesy.svg)
On my current pet guinea pig, just playing around with loading one only mobile css sheet for teh fonez, and a standard sheet for t'others, with an extra sheet only called if the default variant is not set. These are for layout variants, not colour variants.
Antechinus haz done colour variants to death innit
<link rel="stylesheet" media="only screen and (max-width: 900px), only screen and (min--moz-device-pixel-ratio: 1.5) and (max-width: 1140px), only screen and (-o-min-device-pixel-ratio: 1.5/1) and (max-width: 1140px), only screen and (-webkit-min-device-pixel-ratio: 1.5) and (max-width: 1140px), only screen and (min-device-pixel-ratio: 1.5) and (max-width: 1140px)" type="text/css" href="', $settings['theme_url'], '/style_Mobile.css?116" />
<link rel="stylesheet" media="only screen and (min-width: 901px), only screen and (min--moz-device-pixel-ratio: 1.5) and (min-width: 1141px), only screen and (-o-min-device-pixel-ratio: 1.5/1) and (min-width: 1141px), only screen and (-webkit-min-device-pixel-ratio: 1.5) and (min-width: 1141px), only screen and (min-device-pixel-ratio: 1.5) and (min-width: 1141px)" type="text/css" href="', $settings['theme_url'], '/style_Standard.css?116" />';
if ((isset($options['theme_layout'])) && ($options['theme_layout'] != 1))
echo '
<link rel="stylesheet" media="only screen and (min-width: 901px), only screen and (min--moz-device-pixel-ratio: 1.5) and (min-width: 1141px), only screen and (-o-min-device-pixel-ratio: 1.5/1) and (min-width: 1141px), only screen and (-webkit-min-device-pixel-ratio: 1.5) and (min-width: 1141px), only screen and (min-device-pixel-ratio: 1.5) and (min-width: 1141px)" type="text/css" href="', $settings['theme_url'], '/style_' , $settings['theme_layout'] , '.css?116" />';