sherryleeshort on "Misty theme css upgrade help"

I just purchased the css upgrade, and I am completely new to css. I've managed a couple of changes, but am stuck on this: I want to change the color of the headers, which are all the same green, to a dark blue.

I assume this is the chunk of code I want to change (?) :

#content h3 {
font-size: 1.4em;
font-weight:normal;
margin: 1em 0 0;
color: #265e15;
}
#content h4 {
font-size: 1.1em;
margin: 1em 0 0 0;
}
#content h5 {
font-size: 1em;
margin: 1em 0;

I put in the editor:

#content h3 {
color: #191970;
}

And nothing changes.