.dotDotDoting{
			0%
	{
			  width 0px
			  margin-right 15px
	}
	 
			25%
	{
			  width 0px
			  margin-right 15px
	}
	 
			50%
	{
			  width 5px
			  margin-right 10px
	}
	 
			75%
	{
			  width 10px
			  margin-right 5px
	}
	 
			100%
	{
			  width 15px
			  margin-right 0
	}
}
 
      &.dot::after
{
        content '...'
        display inline-block
        vertical-align bottom
        overflow hidden
        width 15px
        animation dotDotDoting 1.2s infinite step-start
}

//Ô­ÎÄÁ´½Ó£ºhttps://blog.csdn.net/weiwenwen6/article/details/89880480