版本：
文件：
- https://cdn.bootcdn.net/ajax/libs/jquery.selectboxit/3.8.0/jquery.selectBoxIt.css
- https://cdn.bootcdn.net/ajax/libs/jquery.selectboxit/3.8.0/jquery.selectBoxIt.min.js
A jQuery plugin that progressively enhances an HTML Select Box into a single option dropdown list. The dropdown list can be optionally styled with jQuery ThemeRoller and optionally animated with jQueryUI show/hide effects.