なんと、styleだけでこんなものが書けるとは。 <div style="width: 200px; height: 200px; border-radius: 50%; background: -webkit-radial-gradient(30% 30%, white, black);"> http://developer.apple.com/library/safari/#documentation/InternetWeb/Conceptual/SafariVisualEffectsProgGuide/Gradients/Gradients.html</div>