Animated Background With Liquid Caustics

Refracted light on the floor of a pool, and the richest surface in this set. It earns a section where the job is atmosphere rather than information: a testimonial band, a closing call to action, a pricing header, the strip above a footer. Because the threads gather and release on their own schedule the frame never repeats, which is what makes it hold up in a section people scroll past slowly.

Three properties decide almost everything. `sharpness` is the difference between broad rippling washes and fine bright threads, `turbulence` between a lazy swell and a churn, and `tilt` controls how much light falls from above, which is what gives the frame a top and a bottom instead of reading as a flat texture. Take `dispersion` up only a little; past about four hundredths the colour fringes stop looking like refraction and start looking like a misregistered print. And keep real reading to a headline here, because bright threads travelling under small type is genuinely hard to read.