Hi @Muhammad Waseem 

On your Developer community login, you can find the Learning Tab, please login to that and you can access materials. 

You can also check YouTube for videos. 

Regards. 

Hi @Rochdi Badis 

May be you can over ride the settings. 

You could assign a common class or a common id for it and adding a constant height and width on the CSS page of your project. 

That would be the most easiest and time saving task to be done. 

I hope it is useful and you got your doubt clarified. 

Regards.