Do creatures on both sides of Blade Barrier benefit from 3/4 cover?

I was looking at the Blade Barrier spell, and I was wondering does the spell have a ‘front’ and a ‘back’? The spell description states:

The wall provides three-quarters cover to creatures behind it

Does this refer to creatures who are behind the ‘back’ of the blade barrier, or does this apply to any creature shooting another creature on the other side of the wall?