This is an epic animation where you can see a mountain range and your mouse moves the sun from behind the mountain to the top of the sky. As you move your mouse you will start to see that the background colour of the sky changes and when the sun reaches the edge of the mountain you will see the sun rays coming out in different angles. This animation was designed by Tristan.
If you are having trouble with the pen, try the archived copy on GitHub
Sun Rays Over Mountain Snippet
See the Pen Lightrays v2 by Tristan (@sinthetyc) on CodePen.0