Which is this spacing between tables?

Question

This is the url: http://rosariodesign.com/leaducate.php This is for a email newsletter

The gray border is a table, which contains another 2 tables inside. You will see that there is a 1px space between the gray border and the content, what is that?

Answer 1

You'll have to ask someone smarter than I to explain it to you, but it's padding on the td that contains your two tables. Fix it with padding: 0, of course, on that td. See this fiddle and look for

this_td_has_padding