前端常见的布局和功能 (持续更新)

趁着博客刚刚支持 ``jsfiddle``， 赶紧写一些demo

## 垂直水平居中

### 通过 line-height 设置单行居中

## 通过 Tabel 表格元素居中

## 通过 Flex 布局居中

## 圣杯布局

## 侧边栏跟随

## 返回顶部

## 铆接点跳转

## 头部悬浮

## 聊天气泡

## 简单的验证码输入

## 简单的iOS的切换按钮

## 侧边栏滑动

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