How do I change the default spacing between images

Hi,

I would like to know how to change the spacing between my images to 18px but still keeping the default padding on each side of the page, I would like it to look just like this but with 18px spacing between each http://www.jakewild.uk/ I know you can do this by editing the cell padding in Avia Builder but in order to keep the full content width the same the far left and right padding needs to be set to 0px meaning that if I want to rearrange the images or add another image I’ll have to amend all of the padding figures each time, I would like to know how to set a default spacing for all padding whilst keeping the full content width the same.

Thanks very much,

Jake