Remove Drupal stylesheets with hook_css_alter

When you start developing themes, you'll find out that there will be a lot of stylesheets loaded in by default. To remove those stylesheets from your own theme's template.php, you have to overwrite hook_css_alter and remove the stylesheets from the array.

To make things a bit clearer, take a look at the following snippet:

php
<?php
/**
 * Remove Drupal's core system stylesheets.
 */
function THEMENAME_css_alter(&$css)
{
    $path_system = drupal_get_path('module', 'system');
    $remove = array(
        $path_system . '/system.base.css',
        $path_system . '/system.menus.css',
        $path_system . '/system.messages.css',
        $path_system . '/system.theme.css',
    );
    // Remove stylesheets which match our remove array.
    foreach ($css as $stylesheet => $options) {
        if (in_array($stylesheet, $remove)) {
            unset($css[$stylesheet]);
        }
    }
}

As you can see, it removes all system module stylesheets from the stylesheets that will be rendered. This can be of course any stylesheet of any module you want.