How to centralize the logos in grid view

Hi there,

How can i centralize the grid of logos? Please see image in atachment, i tried a custom css class to the module and many other ways like modifications on template files, custom.css file but seems not to work, please help me with this.

Thanks in advance.

Please send url your site, i'll check this

Thank you, the url is www.tropigalia.mach.co.mz/index.php/marcas