Prevent demo anchor links from scrolling to page top in styleguide

styleguide.html

@@ -1153,6 +1153,11 @@ var observer = new IntersectionObserver(function(entries) {
 document.querySelectorAll('.reveal, .reveal-scale').forEach(function(el) {
   observer.observe(el);
 });
+
+// Prevent href="#" demo links from scrolling to top
+document.querySelectorAll('a[href="#"]').forEach(function(a) {
+  a.addEventListener('click', function(e) { e.preventDefault(); });
+});
 </script>
 
 </body>