A true volumetric emission/dark nebula: a 3D fBm density field is ray-marched front-to-back, its glow tinted through a Hubble narrowband palette — Hα rose, OIII teal, SII gold — while a low-frequency hue field carves the cloud into distinct line-emission regions. Layered background stars parallax behind the gas and shine through its thinner voids; a scatter of embedded hot stars ionizes the billows around them. The camera drifts slowly forward through the cloud. Hover to steer the parallax, scroll to thicken the gas, press to shift the emission-line palette.