Space between images in gallery

How do I create some space between images? When I insert gallery using [gallery] shortcode, the images are all lined up as one images. Its hard to differentiate two images.

I am looking for a way to make at least 5px space between two images while inserting the gallery.

Can anyone help me please?

Take a look at this page- the images does not have any space in between.

https://www.fundahstic.com/places/india-years/

Thanks