Flex layout method (css3 elastic layout tutorial)

.container{
	align-items: center;
	justify-content: center;

	display: flex;
	background: white url(image/baby.jpg) no-repeat center;
	background-size: auto 100%;
}

.text{
	display: flex;
 	align-items: center;
	height: 3rem;

	color: white;
	font-family: helvetica, sans-serif;
	font-size: 1.5rem;
	font-weight: bold;
	text-transform: uppercase;
	text-shadow:0 0 1.2rem hsla(0,100%,100%,.4);
	box-shadow: 0 0 1.5rem hsla(0,100%,0%,.4);
	border-radius: .5rem;
}

 html {
					height: 100%;
					font-size: 62.5%; /* 10px with default settings */
				}   
				body {		
					margin: 0;
					height: 100%;
					width: 100%; /* width needed for Firefox */

					/* old flexbox - Webkit and Firefox. For backwards compatibility */
					display: -webkit-box; display: -moz-box;
					/* middle-aged flexbox. Needed for IE 10 */
					display: -ms-flexbox;
					/* new flexbox. Chrome (prefix), Opera, upcoming browsers without */
					display: -webkit-flex;
					display: flex;
					
					/* old flexbox: box-* */
					-webkit-box-align: center; -moz-box-align: center;
					/* middle flexbox: flex-* */
					-ms-flex-align: center;
					/* new flexbox: various property names */
					-webkit-align-items: center;
					align-items: center;
					
					
					-webkit-box-pack: center; -moz-box-pack: center;
					-ms-flex-pack: center;
					-webkit-justify-content: center;
					justify-content: center;
					
					background: white url(image/baby.jpg) no-repeat center;
					background-size: auto 100%;
				}
        		
        		/* 	flexbox added below to show it works with anonymous boxes (e.g. text) as well
        			It is not needed to center the heading itself.
        			Rest of the styles are just to make the demo pretty and can be ignored.
        		*/
				h1 {
					display: -webkit-box; display: -moz-box;
					display: -ms-flexbox;
					display: -webkit-flex;
					display: flex;
					
					-webkit-box-align: center; -moz-box-align: center;
					-ms-flex-align: center;
					-webkit-justify-content: center;
					justify-content: center;
					
					-webkit-box-pack: center; -moz-box-pack: center;
					-ms-flex-pack: center;
					-webkit-align-items: center;
					align-items: center;
					
					height: 10rem;
					padding: 0 3rem;
					
					/* background-color: hsla(0, 100%, 0%, .9); */
					color: white;

					font-family: helvetica, sans-serif;
					font-size: 5rem; /* font shorthand doesn’t work with rem in IE10 */
					text-transform: uppercase;
					text-shadow: 0 0 1.2rem hsla(0, 100%, 100%, .4);

					box-shadow: 0 0 1.5rem hsla(0, 100%, 0%, .4);
					border-radius: .5rem;
				}