Gallery Module Tests

Problem: spacing of the thumbnails is for 4 images regardless of how many I add.

How can I make the gallery fill the width with equal-spaced images even if there are only 2 or 3?

For example, here are galleries with 2, 3, and 4 images:

What I Want

In the case of 2 or 3 images, I would like those gallery thumbnails to be equally spaced across the screen like this, yet still have all the features of a gallery:

Gallery Module Tests with supplied CSS added to each module

I

Gallery Module Tests with supplied CSS added to each module

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Map courtesy of Washington state Department of Natural Resources