Add the following under .markdown-preview-view h6:
margin-top: -30px !important
You may have to play around with the numeric value a bit to get it just right or just to your liking.
The CSS above also has an effect on embeds in both Live Preview and Reading modes, so you will probably also need to add some or all of the following CSS:
/* Live preview and popup previews */
div.markdown-embed .markdown-preview-view h6 {
position: relative; /* Changed from absolute to enable verse and SNW counter display in popup previews */
margin-top: -20px !important; /* Note that this affects the top margin in both live-preview embeds and popup previews! Added to enable verse and SNW counter display in popup previews */
}
/* Reading Mode */
.markdown-preview-view .markdown-embed-content p:first-child {
margin: 1px;
margin-top: 25px !important; /* Added to counteract -30px above and match block quotes */
}
I had to add all this to my Bible verse CSS to counteract a bug I documented here.