npm install better-scroll --save
視圖結構：
<div class="wrapper">
<ul class="content">
<li>...</li>
<li>...</li>
...
</ul>
<!-- you can put some other DOMs here, it won't affect the scrolling -->
</div>
引用方式：
import BScroll from 'better-scroll'
const wrapper = document.querySelector('.wrapper')
const scroll = new BScroll(wrapper)
