The easiest way to get the CSS: open Fluxer's settings → Appearance, customise your theme, click Export as CSS, then paste the contents below. Or use the Load current theme into editor button inside the CSS overrides box.

Pick the 5 colours that best represent your theme — typically bg / surface / hover / accent / text.

Upload an image and we'll host it on the Fluxer World CDN. The URL is copied to your clipboard so you can paste it into your CSS, e.g. background-image: url('...');. Hotlinking from external hosts works but the link can break — uploading here keeps your theme working long-term.

A :root { … } block with CSS variable overrides. Use Export as CSS from inside the app to get yours.