版本：
文件：
- https://cdn.bootcdn.net/ajax/libs/stickyfloat/7.5.0/stickyfloat.js
- https://cdn.bootcdn.net/ajax/libs/stickyfloat/7.5.0/stickyfloat.min.js
Makes it possible to have a fixed position element that is relative to it's parent. In other words, floats an element along while scrolling...but does this good.