Bezier-rs: Add hash URLs for individual API examples (#968)

* Handle displaying single demos

* Address comments

* Update eslintrc

* Add hash links

* Use hash instead of pathname

* Address small nits

* Change url format

* CSS improvements

---------

Co-authored-by: Keavon Chambers <keavon@keavon.com>

website/other/bezier-rs-demos/src/style.css

@@ -1,11 +1,17 @@
 html,
 body {
-	height: 100%;
 	font-family: Arial, sans-serif;
 	text-align: center;
+}
+
+body > h1 {
 	margin: 40px 0;
 }
 
+body > h1 ~ :last-child {
+	margin-bottom: 40px;
+}
+
 body > h1 + p {
 	max-width: 768px;
 	line-height: 1.4;
@@ -29,8 +35,24 @@ body > h2 {
 }
 
 .demo-pane-header {
+	display: inline-block;
+	position: relative;
 	margin-top: 2em;
 	margin-bottom: 0;
+	padding: 0 1em;
+}
+
+.demo-pane-header a {
+	display: none;
+	position: absolute;
+	left: 0;
+	text-decoration: none;
+	color: inherit;
+	opacity: 0.5;
+}
+
+.demo-pane-header:hover a {
+	display: inline-block;
 }
 
 .demo-pane-container {