Black background behind text and images without white gaps

Site URL: https://youbydiana.com

Hi there
Hopefully someone can help me here. I just switched from Wexley to Skye because of the blog options. Now my black backgrounds don't work anymore. (mainly on the homepage of www.youbydiana.com)  
I have a white gap between black background in Skye which was not the case in Wexley.

Here is the code I have used.

{background: #000000;
color: white;
padding: 20px;
text-align: center;}

The weird thing is that the white gaps dont show in editing mode and appear as soon as I hit save. I was already in touch with Squarespace but they said they can't help because it is code stuff.

Does anyone know how I can loose the white gaps? Thank you so much!

Hi. Which white gap? Can you take a screenshot