style: partition stacked TOCs (#121)

* style: partition stacked TOCs

* style: account for captioned TOCs

Author: medubelko

canonical_sphinx/theme/static/custom.css

@@ -373,6 +373,20 @@ details summary {
     text-decoration: underline;
 }
 
+/* Partition stacked TOCs */
+.sidebar-tree > ul + ul {
+    margin-top: 1em;
+    padding-top: 1em;
+    border-top: 1px solid var(--color-background-border);
+}
+
+/* Partition captioned TOCs */
+.sidebar-tree > p.caption {
+    margin-top: 2em !important;
+    padding-top: 2em !important;
+    border-top: 1px solid var(--color-background-border);
+}
+
 /* Make inline code the same size as code blocks */
 p code.literal {
     border: 0;