Is it acceptable to wear a black dress to a late afternoon/evening wedding?

We’re going to a wedding on Sunday. The ceremony is at 4:30, followed by drinks with the actual reception and dinner around 6:00. The invitation didn’t say “black tie” or any reference to the formality of the event.

This morning I went shopping for a dress, and the only one my husband and I could agree on (he has a much better fashion sense than I do) is a little black dress. The jury still seems to be out on whether or not black is acceptable at a wedding. I lightened up the dress with cute silver sandals and matching accessories. Is this OK, or should I torture myself with further dress shopping to find something more colorful?