css 设置滚动条。

项目中有用到记录一下。

CSS滚动条选择器节

你可以使用以下伪元素选择器去修改各式webkit浏览器的滚动条样式:

• ::-webkit-scrollbar — 整个滚动条.
• ::-webkit-scrollbar-button — 滚动条上的按钮 (上下箭头).
• ::-webkit-scrollbar-thumb — 滚动条上的滚动滑块.
• ::-webkit-scrollbar-track — 滚动条轨道.
• ::-webkit-scrollbar-track-piece — 滚动条没有滑块的轨道部分.
• ::-webkit-scrollbar-corner — 当同时有垂直滚动条和水平滚动条时交汇的部分.
• ::-webkit-resizer — 某些元素的corner部分的部分样式(例:textarea的可拖动按钮).

语法：::-webkit-scrollbar { styles here }

demo：

.visible-scrollbar, .invisible-scrollbar, .mostly-customized-scrollbar {
  display: block;
  width: 10em;
  overflow: auto;
  height: 2em;
}
.invisible-scrollbar::-webkit-scrollbar {
  display: none;
}

/* Demonstrate a "mostly customized" scrollbar
 * (won't be visible otherwise if width/height is specified) */
.mostly-customized-scrollbar::-webkit-scrollbar {
  width: 5px;
  height: 8px;
  background-color: #aaa; /* or add it to the track */
}
/* Add a thumb */
.mostly-customized-scrollbar::-webkit-scrollbar-thumb {
    background: #000; 
}
<div class="visible-scrollbar">Thisisaveeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeerylongword</div>
<div class="invisible-scrollbar">Thisisaveeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeerylongword</div>
<div class="mostly-customized-scrollbar">Thisisaveeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeerylongword<br>
And pretty tall<br>
thing with weird scrollbars.<br>
Who thought scrollbars could be made weeeeird?</div>

参考链接：https://developer.mozilla.org/zh-CN/docs/Web/CSS/::-webkit-scrollbar