Restyle figure captions

* Change 11ty/liquid script to wrap the auto-generated "Figure X" in a `<span>`
* Add CSS overrides

Closes #4241

Author: patrickhlauke

11ty/CustomLiquid.ts

@@ -243,7 +243,7 @@ export class CustomLiquid extends Liquid {
           $("figcaption").each((i, el) => {
             const $el = $(el);
             if (!$el.find("p").length) $el.wrapInner("<p></p>");
-            $el.prepend(`Figure ${i + 1}`);
+            $el.prepend(`<span>Figure ${i + 1}</span>`);
           });
 
           // Remove spurious copy-pasted content in 2.5.3 that doesn't belong there

css/base.css

@@ -430,6 +430,25 @@ margin-right:.8em;
   margin-left: 2em;
 }
 
+/* overrides for restyled figure captions */
+
+figure {
+  margin: 2em 0;
+}
+
+figcaption {
+	font-weight: initial;
+	border-bottom: initial;
+  font-size: 0.9rem;
+  padding-left: 1em;
+  border-left: 2px solid #005a9c;
+  border-left: 2px solid var(--w3c-classic);
+}
+
+figcaption > span {
+  font-weight: bold;
+}
+
 @media (max-width: 35em) {
 	.nav-container {
 		padding: 0;
@@ -438,7 +457,7 @@ margin-right:.8em;
 		display: inline-block;
 		width: calc(100% - 2em);
 	}
-	@supports (display:gred) {
+	@supports (display:grid) {
 		#site-header {
 			padding-left: 0;
 		}