One-time Fading loading screen

The client had a loading screen customization on her site that allowed her to showcase a welcome message when a user landed on the homepage. However, she was looking for a way to make sure that that only happened the first time the visitor opened up her site, instead of every time the homepage was visited.

Using the existing code as a base, I made the necessary HTML and CSS adjustments required for the screen to work with the one-time customization, and implemented the timing limitation that would effectively hide the loading screen once a user had already seen it the first time during their entire visit.