метод 1

.container {
	box-sizing: border-box;
	display: inline-block;
	width: 100%;
	zoom: 1;
}

метод 2

.container:before,
.container:after {
	content: " ";
	display: table;
}
.container:after {
	clear: both;
}
.container {
	zoom: 1;
}

метод 3

.container {
	overflow: hidden;
	display: block;
	zoom: 1;
}