Hi, on this server:
https://www.gametracker.com/server_info/88.198.47.43:27014/

or any css servers, the image of current map is not showing correctly.

The correct link is in http, but on this page is in https and showing a bug note: "Invalid SSL certificate

The origin web server does not have a valid SSL certificate."

GameTracker doesn't fully support HTTPS.

Try using this link to view the page;
http://www.gametracker.com/server_info/88.198.47.43:27014/

Also, don't forget to use - http://www.GameTracker.com to enter the site.

See more about the feature request to support HTTPS.
(it's not a bug):

http://www.gametracker.com/forums/forum.php?site=1&thread=92017