docs: add MeshCore board signal tables and normalise size formatting

docs/_stylesheets/extra.css

@@ -198,7 +198,7 @@ body {
 }
 
 .md-typeset code,
-.md-typeset pre > code {
+.md-typeset pre>code {
     border-radius: 10px;
 }
 
@@ -247,6 +247,7 @@ body {
 }
 
 @media screen and (max-width: 76.2344em) {
+
     .md-content__inner,
     .md-sidebar__scrollwrap {
         border-radius: 14px;