Resize Headline Font for Mobile

After 3 weeks of trying to solve the same problem, and not succeeding, I am falling on the mercy of the forums.

Site: changeclothesbrand.com

The large text headlines on the homepage and various other page run over when (whole word not visible) when viewed on mobile. I’m not very versed in css, but what I’ve tried hasn’t worked so far. Seems like it should be a simple process, so anybody that can help me crack the code would be appreciated.

My end goal would be to have large text like LoungeLizard.com, but have it resize to fit on mobile when viewed there.

Thanks in advance!