Add support for nav without JS enabled

Page defaults to assuming JS is not available. When navigation JS loads it adds a JS class to <html>.

Without that class, desktop dropdown is opened on hover or keyboard focus.

Author: gellowg

css/main.scss

@@ -343,7 +343,9 @@ header {
       transform: translateY(-50%) scale(1);
     }
 
-    &.dropdown.open .dropdown-content {
+    &.dropdown.open .dropdown-content,
+    html:not(.js) &.dropdown:hover .dropdown-content,
+    html:not(.js) &.dropdown:focus-within .dropdown-content {
       visibility: visible;
       opacity: 1;
       pointer-events: auto;

js/hamburger.js

@@ -1,3 +1,5 @@
+document.documentElement.classList.add("js");
+
 document.addEventListener("DOMContentLoaded", () => {
   const hamburger = document.getElementById("hamburger");
   const menu = document.getElementById("hamburger-menu");