I think the shower curtain has to be white, perhaps in a textured fabric. They always advise to hang it high so if you have to add fabric at the bottom, maybe tie in the blue and or grey there? I think it looks nice when there are grommets and it goes through a pole.

White would look nice. I never heard of a shower curtain having to be hung high.??

It's not a window.

White.

Agree with above. It has to be white with a texture in it, and hang it as high as you can. I think what's really important in bathrooms is to mix your metals.

White or navy.

White

Waffle weave white, I don't think you should hang it any higher than normal nor add a stripe of fabric to the bottom.

Since everyone is suggesting white, and waffle eave at that, I will mention that I bought one at Target about 5 years ago but pretty sure they always have it. It does look very nice and I have washed it a few times ( I do use a plastic liner) and it washes well. I just looked, and they have this one (somehow I think mine is 'beefier " but anyway...Target Waffle Weave. while looking on Target I saw this one which is mostly white but has a navy bottom...white with navy oxford

The first one

I have that one and it’s a steal for $18. RH one is luxuriously heavier, it was in a hotel I recently stayed at, but $$$.

What about this? White Curtain w/ Black/gray ribbon top & bottom

@Jan Moyer - No need to be sassy? lol Obviously white, but there are so many different types of white shower curtains. Hence why I asked for a second opinion.

I love the Restoration Hardware Satin Stitch Hotel Shower Curtain and they do offer one with a navy stitch.

There's also this Pottery Barn Morgan Shower Curtain in twilight.

A simple one tone curtain. With the rug and tile being almost identical, something "plain" will make that transition much easier and nicer on the eye.