🐛 Hide preloader once the app loaded

Reviewed-on: #13

src/ui/_base.scss

@@ -214,6 +214,11 @@ input {
     font-family: inherit;
 }
 
+// Hide the preloader as soon as the application is loaded and ready to be rendered
+#preloader {
+    display: none;
+}
+
 #main {
     height: 100%;
     width: 100%;