Fixed mobile scrolling issues

fixes #12

- added background color to the mobile menu actions
- disabled root scrolling when the mobile menu is opened which fixes the duplicate scrolling issue

assets/js/main.js

@@ -0,0 +1,48 @@
+/* Mobile menu burger toggle */
+(function () {
+    const navigation = document.querySelector('.gh-navigation');
+    const burger = navigation.querySelector('.gh-burger');
+    if (!burger) return;
+
+    burger.addEventListener('click', function () {
+        if (!navigation.classList.contains('is-open')) {
+            navigation.classList.add('is-open');
+            document.documentElement.style.overflowY = 'hidden';
+        } else {
+            navigation.classList.remove('is-open');
+            document.documentElement.style.overflowY = null;
+        }
+    });
+})();
+
+/* Add lightbox to gallery images */
+(function () {
+    lightbox(
+        '.kg-image-card > .kg-image[width][height], .kg-gallery-image > img'
+    );
+})();
+
+/* Responsive video in post content */
+(function () {
+    const sources = [
+        '.gh-content iframe[src*="youtube.com"]',
+        '.gh-content iframe[src*="youtube-nocookie.com"]',
+        '.gh-content iframe[src*="player.vimeo.com"]',
+        '.gh-content iframe[src*="kickstarter.com"][src*="video.html"]',
+        '.gh-content object',
+        '.gh-content embed',
+    ];
+    reframe(document.querySelectorAll(sources.join(',')));
+})();
+
+/* Turn the main nav into dropdown menu when there are more than 5 menu items */
+(function () {
+    dropdown();
+})();
+
+/* Infinite scroll pagination */
+(function () {
+    if (!document.body.classList.contains('home-template') && !document.body.classList.contains('post-template')) {
+        pagination();
+    }
+})();