Changeing light cycle

Okay guys... It is summer and my room keeps warming up too 85 degrees...

can I change my light cycle from 10am-10pm to 10pm-10am

I am three weeks into flower.

Do you think this will achieve the desired effect of lowering my room temps?

also I have a window ac unit, Is there a way to block it off so that no light comes into my room???

85 is hot but its withing range just barely.if it gets any hotter then 85f yes i would deff switch your light cycle.use tape on your window to block light