Box Shadow Generator

A single box shadow almost always looks flat, and the reason is that real shadows are not one shadow. Physical objects cast a tight, dark contact shadow right at the surface and a wider, softer ambient shadow further out. Layering two or three shadows with increasing blur and decreasing opacity is what separates a shadow that looks designed from one that looks like a default.

Keep the vertical offset positive and the horizontal offset at or near zero: that implies a light source above, which is what every interface convention assumes. A shadow offset sideways reads as wrong even to people who cannot say why.