Northern lights for the web. Three ribbons of light hang over a deep blue-violet night sky, each with a bright rippling lower edge that fades upwards in fine vertical rays. The hems glow teal and green and melt into pink as they rise, and small stars twinkle behind them.

It is a dark background, made for night-mode hero sections, music, event and launch pages, and title cards. Every colour is a setting, along with brightness, how high the ribbons hang, how much they ripple and how bright the stars are. The demo has three presets: Northern lights, Rose night and Arctic.

What you get: a GLSL ES 3.00 fragment shader for plain WebGL2, an ES module that returns a three.js ShaderMaterial, a Shadertoy version, and a demo page that runs offline with a small settings panel. For video editors there is a 10-second 1920 x 1080 H.264 loop that plays end to start without a seam.

It runs in one pass with no textures needed, at about 2.1 ms of GPU time per frame at 1920 x 1080 on a recent laptop. The README covers set-up in WebGL2, three.js and Shadertoy, every uniform with its default and range, and performance notes.