Slip length for bridesmaid dress?

[Fluffyfluffflufffluff]

My floor-length bridesmaid dress is a bit see-through in certain lights so I'm thinking of getting an underskirt/half slip to be safe.

M&S only have knee-length ones. Will this work with a long dress or will it look weird?

Also would white be the colour to go for if the dress is light pink?

Cheers

I think that an ankle length would be better. There's some on amazon and eBay, but obvs not sure of the quality.

If you can get nude colour it works best.