.gallery-main{
	float: left;
	margin-right: 20px;
}
.gallery-main a{
	display: block;
	margin-bottom: 10px;
}

@media (max-width:500px){
	.gallery-main{
		float: none;
		margin-right: 0;
		margin-bottom: 20px;
	}
	.gallery-main:after{
		display: block;
		clear: both;
		content: '';
	}
	.gallery-main a{
		float: left;
		width: 49%;
	}
	.gallery-main a:nth-child(1){
		width: 100%;
	}
	.gallery-main a:nth-child(2){
		width: 49%;
	}
	.gallery-main a:nth-child(3){
		width: 49%;
		margin-left: 2%;
	}
	.gallery-main a img{
		display: block;
		width: 100%;
		box-sizing: border-box;
	}
}