DP and I are going to a wedding evening reception in a couple of weeks. It's quite informal I think, eg we've been asked to bring some food. I haven't got a clue what to wear; Dp says "jeans?" 
I don't know them and it'll be the first time I meet DP's colleagues so I don't want to look overdone or like i've not made an effort!
I'm 39, dark brown hair, quite slim flat chested
Any links or pictures welcome! Please help!