Actually you need to style the wrapping
P tag with
line-height: 0px; but this isn't possible anyway since there is no way to put inline-styling into this element.
I'm afraid but you probably should think about something different. Make the "negative" into a "positive" which means - try to use that "space" and make the best of it.
Yes, I´ll have to think about a new design with less complexity. Thanks for your support, mate!