DH's work is doing their annual Christmas party this weekend, which is always a lot of fun - his coworkers, even his boss(es), are pretty laid-back and fun. It's being hosted at a restaurant, and has a casino theme. On the invite, it says "cocktail attire requested." Style dress-codes like this one are 100% not my (or DH's) forte. We're clearly not classy enough.

Anyway, I did my Google-ing and was a bit overwhelmed with suggestions across the board. I'm wondering if you guys could share your thoughts on a couple specific questions:
For DH: would a darker grey suit work as opposed to black? There's a very light pinstripe on the suit. Or would dress slacks and a jacket be a better choice?
For me: I already own this dress and it still fits. I'm not sure if lace is okay for cocktail attire...would this dress fit in the cocktail attire dress code?
I don't think that we have to perfectly nail it, since I don't think it's going to be a super formal event, but I don't want to be wildly off the mark.
Re: NBR: Cocktail Attire
Your dress is the appropriate length, but from the small image it looks a little summery to me. It wouldn't if you paired it with black tights, though.
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