add section 2, 3 & 4 for desktop

website/src/css/design3.css

@@ -228,7 +228,10 @@ html {
     font-family: GT-Walsheim, Gilroy, Helvetica, sans-serif;
 }
 
-html, body { background:#000; }
+html,
+body {
+    background: #000;
+}
 
 .hidden {
     display: none !important;

website/src/js/design3.js

@@ -29,4 +29,4 @@ document.addEventListener('DOMContentLoaded', () => {
         testflightBtn.classList.remove('hidden');
         androidBtn.classList.remove('hidden');
     }
-});
+});