@RvR thank you ! 

i do use google inspect but i could not find the basic class, it was all long stuff .. i'm learning atm, guess forever !! :( 

:) 

Ok.

I forgot you might be using Aalborg theme. In this case, check this:

https://github.com/Elgg/Elgg/blob/2.3/mod/aalborg_theme/views/default/elements/buttons.css#L29

or

https://github.com/Elgg/Elgg/blob/2.3/mod/aalborg_theme/views/default/elements/buttons.css#L73

@RvR thank you ! 

Hope adding this to your css file custom plugin extending elgg.css view should do the trick.

.elgg-photo {
    
     max-width: 100% !important; 
     width: 100% !important;
     
}

Or, if you have your website Url, it will make it easier to check your CSS on the browser and suggest CSS change to your website.

thank you thats worked