Background image for greenstone collections

[oranfry]

The method for getting the left-aligned strip of waves as a background image in greenstone collections is severely old-school, and wider monitors are now revealing its flaws. Instead of a 1500px-wide background image which is mostly whitespace, we need an image which is only as wide as the actual strip of waves, and to use css to align it and make sure it's not repeated. Something like:

background: transparent url('waves.gif') scroll repeat-y left top;