The game page finally has the cool looking snow effect I wanted. I stacked an animated gif snow effect (16 frames) over the static deer trail.
Here is the CSS section that does it:
#body{background-image:url("[url]https://rpgmaker.net/media/content/users/26942/locker/Snow.gif[/url]"),
url("[url]https://rpgmaker.net/media/content/users/26942/locker/DeerTrail.jpg[/url]");
background-repeat:repeat,no-repeat;
background-attachment:fixed,fixed;
background-size:64px 64px,100% 100%;}
Big thanks to
GreatRedSpirit for his example of stacked backgrounds. See
his post if you want to try animated background on your game page.