HTML&CSS - Position percentage

by Code_Garage

HTML

<div class="container" id="blue">1.</div>

CSS

body {
  min-height: 600px;
}
.container {
  font-family: arial;
  font-weight: bold;
  width: 50px;
  height: 50px;
  margin: 5px;
  padding: 5px;
  color: white;
  box-sizing: border-box;
}
#blue {
  background: #3498db;
	position: absolute;
	top: 50px;
	left: 50%;
}