I am Hiding/showing submit button in infopath based on the checkbox validation. When I check preview in infopath. it works perfectly. but When I publish form on Sharepoint Site. Submit button background white-out and only border is visible.
InfoPath creates HTML that is a few years behind the times, i.e. html 4, not 5. I see you're using SharePoint 2013. It's possible that some CSS is interfering with the button CSS class. You may want to fire up the Designer Tools (F12) to see what CSS style is applied to the button and where it comes from. That will give you a handle on how to fix things.
What happens if you use exotic colours for the button instead of the standard gray in gray?