Gallery lightbox image overlay button always visible before hover

I would like to have the Gallery lightbox image-overlay button (the circle button with the double arrow) stay always visible even before hovering over the first image just to be sure the user clicks to see the gallery lightbox.
I tried tampering with the css but I think alterations have to be made in the avia.js.
Of course it would be better if I could manage by customising the css only (I am no programmer… I just get a little reading the code).
Is there any way to get it right?
The enfold template is a great template!

Thanks you…