Hirama666 thank you for your answer. I believe you then need a custom theme with a CSS rule to center the text. And the right scope (this one is going to be tough...), so it only applies to the Advanced Report.
Did you have a look to the WPadmin theme icon sets README?
The stylesheet.css file simply links to the WPadmin theme's stylesheet
and redefines the module icons.
Feel free to add your custom styles or redefine the WPadmin ones in the stylesheet.