表示動作検証:
firefox 3.5.5 (osx)
safari 4.0.4 (5531.21.10) (osx)
chrome 4.0.249.43 (mac)
safari 3.2.2 (525.2.8) (win)
chrome 1.0.154.48 (win)
ie 7.0.5730.13 (win)
opera 9.64 build 5270 (osx)