One box-shadow is cool and all, but check out Philipp Brumm’s tool for building out comma-separated multiple box-shadows, which result in a much smoother and more natural look.
This reminds me very much of the idea for easing linear-gradient. In a gradient, this smoothing effect is handled by multiple stops with the position and color eased (sloped) rather than linear (straight). The result is noticeably smoother and a more pleasing look.
See the Pen
smooth box-shadow by Chris Coyier (@chriscoyier)
on CodePen.