Clay controls
Clay is a light inner highlight plus a darker outer shadow on a pastel base.
Build the clay look: puffy rounded shapes with a big soft inner highlight and a crisp outer shadow. Tune depth, puffiness and colors, then copy the CSS.
Clay is a light inner highlight plus a darker outer shadow on a pastel base.
Both use layered shadows, but clay goes bolder: a bright white inner highlight on the top-left edge, a saturated darker tone on the bottom-right, and a crisp colored outer shadow. The result reads as molded plasticine rather than machined metal, which is why claymorphism suits playful, friendly interfaces.
Clay loves pastels: pink, mint, sky, peach and lavender. The base must be light enough that a white inner highlight is visible, and saturated enough that the darker outer shadow reads as the same hue. Grays and near-blacks just look like plain shadows.