html { height: 100%; width: 100%; min-height: 100%;}

body {background:black; display:block; min-width: 100%; min-height: 100%; height: 100vh;}

.main-container {display:flex; width: 100%; height: 100%;  align-items: center;
  justify-content: center;}

h1{background: url(logo.png);
	margin: 20px;
	    background-repeat: no-repeat;
	        background-position: center;
    display: inline-flex;
    text-decoration: none;
    width: 900px;
    height: 300px;
    background-size: 100% auto;
    text-indent: -9999px;
    font-size: 0;
    line-height: 0;}