I use this to link to my CSS file:
$css_file = plugin_dir_path( __FILE__ ) . 'MapStyle.css';
echo '<link rel="stylesheet" href="', $css_file, '" >';
Which (correctly) resolves as (echo $css_file):
/var/www/mysite/wp-content/plugins/TheMapPlugin/MapStyle.css
But the css file is never loaded, because the browser is looking for the file:
http://www.example.com/var/www/mysite/wp-content/plugins/TheMapPlugin/MapStyle.css
What am I overlooking here? All help appreciated!