解决图片加载闪烁问题

.btn{
			display: block;
			width: 93px;
			height: 29px;
			background-image: url(./1.png);
			
		}
		.btn:hover{
			background-position: -93px 0;
		}
		.btn:active{
			background-position: -186px 0;
		}