[AstralStorm]

An image gradient then. 1 px wide perhaps, or high. Few problems resizing it (even on client) and it should be reusable.

[tiborsaas]

I think the point is not to get away with the scaling problem.

Here's one service I used in a project's development mode:

https://dummyimage.com/2500x2000/000/09f.png&text=HackerNews

In the production build I changed it to the real host.