== 可能用到 ==
 * [http://www.admixweb.com/2010/05/12/creating-a-bubble-coda-style-with-css3/ 氣泡彈出效果]：用於說明

== Ref == 
* [http://woorkup.com/wp-content/uploads/2009/12/HTML5-Visual-Cheat-Sheet1.pdf HTML5的視覺小抄]