Outfit: Whites at the Office

It's no secret that I'm enjoying the summer-months working full time, not that we can call it summer at the moment, but that's a whole different story. Since 3 years (Augustus 3rd 2009, will never forget the day I started working full time, kissed my life away ;)) I work full time, not the same job, but still: in the office. Every summer I find it hard to dress for work. I want to be taken seriously (which is hard when you look 16 years old, but actually are a 28 year old MSc), but want to dress like my cheerful young self. In the winter it's easier to dress for the office: blacks and throw a jacket on top. Your good to go. But summer is harder, blacks are too hot and so is a jacket. This is an example of what I wear to the office now: all whites, light colored heels and your good to go. (Needlessly to say: I don't wear this outfit when I'm going on a sales pitch, or meeting with "the people up high" haha) 
Have you guys got tips for me what to wear to the office during summer? I would love to hear them! 
I'm wearing:
Star Top: Zara | White Jeans: H&M | Heeled Boots: Mango | Feather earrings: H&M Divided
Photo's: by My life as Matt