We're currently using this smoke animation here: https://codepen.io/Irehan/pen/YgyozL
This is the code we've been trying to amend to change the background colour:
gl.clearColor( 0.0, 0.0, 0.0, 1.0 );
We've tweaked the config values slightly to get it running well and it's working really nicely.
The last thing we have to do is change the background colour from #000 to #1a1422 however, I can't seem to get it working despite changing the clearColor line to a different hue.