Gallery Spacing between images fix – wraps unless I add 1 more column

I am trying to add spacing between gallery thumbnails. I asked in the past and you suggested this.
#top #wrap_all .avia-gallery-1 .avia-gallery-thumb a {
margin-right: 10px;
}

It always wrapped some images to a new row.. So I didn’t use it.
I tried to use it again and I found something out.
It does add spacing as desired, however in order to not have the last image wrap to a second row, I have to specify 1 more column than I have images. For example if I have 8 images, I specify 9 columns. Then all images space out on one row as I desire. HOWEVER, they are not centered. There is space at the right. Probably that phantom column. How can I compensate for this?
Thank you.
Version 3.8.4

• This topic was modified 7 years, 11 months ago by icvenfold.