body {
  font-family: Arial, Helvetica, sans-serif;
  background-image: url('../img/birkenweg_sued_640.jpg');
  background-repeat: no-repeat;
  background-size: cover;  
  box-sizing: border-box;
}

/* Style the header */
header {
  background-color: transparent; /*#666;*/
  padding: 30px;
  text-align: center;
  font-size: 35px;
  color: grey;
}

/* Create two columns/boxes that floats next to each other */
article {
  /*float: left; */
  padding: 20px;
  width: 40%;
  text-align: center;
  background-color: transparent;/*#f1f1f1;*/
  height: 300px; /* only for demonstration, should be removed */
}

/* Clear floats after the columns */
section::after {
  content: "";
  display: table;
  clear: both;
}

/* Style the footer */
footer {
  background-color: #777;
  padding: 10px;
  text-align: center;
  color: white;
  position: absolute;
  bottom: 10px;
  left: 5%;
  width: 90%;
}
button {
	width: 200px;
	height: 100px;
}
a {
	margin-right: 40px;
}

.center {
  float: left;
  position: relative;
  left: 50%;
  transform: translateX(-50%);
}