We're trying to remove/reduce the large space placed after headings. We'd like the regular body text to start pretty much immediately following an <h4> (for instance). We like that there be space ABOVE the headings.

I thought that inserting

"h1, h2, h3, h4, h5, h6 {
margin-top: 10px;
margin-bottom: 0;
padding-top: 0;
padding-bottom: 0;
}"

into "CSS Inserts" would override the "margin-bottom: 10px;" I'd found in the "style.css" file, but the space following the <h4>'s is still there.

Do I have to actually edit the "style.css"? Should we EVER be making changes to "style.css"??

I am having fun! Despite what's thought about us "old dogs" -- we can learn a new trick now and then AND we really enjoy the process!

You should not edit style.css if possible. CSS Edits should always overwrite style.css

Even if the margin is 0, h1-6 heading still have a minimum space around them. Add line-height: value; or negative margins margin-bottom: -5px; to further decrease the margin below/above headings

I am using a single heading type (h2) in the following example as you probably wouldn't want to give all heading h1-h6 the same line height:

h2 {
line-height: 0.8;
}

The value can be just a number (x times of normal), px or em.

To limit the style to the content of post/page bodies:

.post-bodycopy h2 {
...
}

or

.post-bodycopy h2,
.post-bodycopy h3,
.post-bodycopy h4,
.post-bodycopy h5 {
...
}