纯CSS制作一个简单气泡对话框（图文详解）

.div::after{

    content: '';

    width: 0;

    height: 0;

    border: 20px solid;

    position: absolute;

    bottom: -36px;

    left: 140px;

    border-color:  #fff transparent transparent;

}

.div{

            width: 200px;

            height: 100px;

            border: 2px  solid #ff0;

            border-radius: 7px;  /*圆角弧度为7px*/

            position: relative;

        }