See the Pen Drop E by Chris Lowe (@alltimelowe) on CodePen.

Set in Monoton, I’ve finally found an excuse to animate a rainbow gradient, woah. But seriously; Monoton is inspired by Prisma, a display face designed in 1931. Monoton is purely a web font and is intended for headline display.

To achieve the animated effect I created a simple rainbow gradient, but added an extra red value on the end to make it seamless. Then a simple keyframe animation to move the background on an infinite loop and voila. The background text clipping is achieved through background-clip and text-fill color.