Is it OK to call my crush "dude" or "bro?"

So this chick I'm into bumped into me the other day and she almost fell over lol. And we joke about it and I told her she was as tough as my guy friends so now I call her dude and bro whenever we talk. She said she wasn't sure how she felt about it. So would it offend her if I called her bro and dude like I call my guy friends? I don't want her to think I don't find her attractive. We work together by the way so I see her at least twice a week.
Is it OK to call my crush "dude" or "bro?"
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