<div class="box1">

	<div class="divA">DIVA</div>

	<div class="divB">DIVB</div>

</div>

<style type="text/css">

			* {

				margin: 0;

				padding: 0;

			}

			.box1 {

				width: 100%;

				height: 300px;

				background: #008000;

				padding:1px;

				box-sizing: border-box;

			}

			.divA {

				width: 150px;

				height: 150px;

				background: red;

				text-align: center;

				float: left;

			}

			.divB {

				margin-left: 150px;

				height: 260px;

				background: blue;

				text-align: center;

				margin-top: 20px;

			}

		</style>