Improved nav UI hiding behavior on mobile

assets/js/script.js

 		if (!GW.scrollState.siteNavUI[0].hasClass("hidden")) toggleSiteNavUI();
 	}
 
-	// On mobile, make site nav UI translucent on ANY scroll down.
-// 	if (GW.mediaQueries.mobileNarrow.matches)
-		GW.scrollState.siteNavUI.forEach(element => {
-			if (GW.scrollState.unbrokenDownScrollDistance > 0) element.addClass("translucent-on-scroll");
-			else element.removeClass("hidden");
-		});
+	// Make site nav UI translucent when scrolling down.
+	GW.scrollState.siteNavUI.forEach(element => {
+		if (GW.scrollState.unbrokenDownScrollDistance > 0) element.addClass("translucent-on-scroll");
+		else element.removeClass("hidden");
+	});
 
-	// Show site nav UI when scrolling a full page up, or to the top.
-	if ((GW.scrollState.unbrokenUpScrollDistance > window.innerHeight || 
-		 GW.scrollState.lastScrollTop == 0)) showSiteNavUI();
+	// On desktop, show site nav UI when scrolling a full page up, or to the
+	// the top of the page.
+	// On mobile, show site nav UI translucent on ANY scroll up.
+	if (GW.mediaQueries.mobileNarrow.matches) {
+		if (GW.scrollState.unbrokenUpScrollDistance > 0)
+			showSiteNavUI();
+	} else if (   GW.scrollState.unbrokenUpScrollDistance > window.innerHeight
+			 || GW.scrollState.lastScrollTop == 0) {
+		showSiteNavUI();
+	}
 }
 
 function toggleSiteNavUI() {