minifying css in drupal and getting the original source css

Question

We have inherited a drupal 7 installation. We have the source code. When we look on the front end there are series a of minified css files named like below. We are interested in getting the original source css files. I have no experience in drupal css minification. Does this kind of output look like out the box drupal minification. If so is there a location that specified the exact css that was used?

 <link type="text/css" rel="stylesheet" href="http://www.mydomain.com/sites/default/files/css/css_pbm0lsQQJ7A7WCCIMgxLho6mI_kBNgznNUWmTWcnfoE.css" media="all" />
<link type="text/css" rel="stylesheet" href="http://www.mydomain.com/sites/default/files/css/css_hYCLW089C9S9sP3ZYkuG6R-Q5ZHbEhblZBFjwZ_bE_I.css" media="all" />
<link type="text/css" rel="stylesheet" href="http://www.mydomain.com/sites/default/files/css/css_YYoEBheeHSoZ5EBVRncs-cuvNClW-5FNm_tmYaEdRwM.css" media="all" />
<link type="text/css" rel="stylesheet" href="http://www.mydomain.com/sites/default/files/css/css_5-5L742ZPRdlG5Jq9Yz3AIRJ3MBxYr6H_bolFIoqd68.css" media="all" /> 

Each css file that we see on the front end is collection of multiple css files.

Answer 1

Yes that looks like Drupal's built in CSS aggregation.

The easiest solution would be to turn aggregation off temporarily. Then you'll see the original sources in the markup.

You can turn it off at the admin/config/development/performance page.

Answer 2

In addition to what Clive said. The default location of the css file would be in the theme directory. Navigate to:

root/sites/all/themes/[select your theme that is listed as the active theme in the appearance admin page]/style.css

If you do not see the style.css go the themes ".info" in that directory and in that file it will tell you where the .css file(s) are located.