*{/*reset*/
  box-sizing: border-box;
}

body{
  font-family: Arial;
  padding: 10px;
  background: #dddddd;
}

.header {
  padding: 30px;
  text-align: center;
  background: #ffffff;
}

.header img{
  width : 50px;
  float: left;
  padding-top: 35px;
}

.header h1{
  font-size: 50px;
}

.button {
  display: inline-block;
  border-radius: 4px;
  background-color: #666666;
  border: none;
  color: #FFFFFF;
  text-align: center;
  font-size: 28px;
  padding: 20px;
  width: 23%;
  transition: all 0.5s;
  cursor: pointer;
  margin: 5px;
}

.button span {
  cursor: pointer;
  display: inline-block;
  position: relative;
  transition: 0.5s;
}

.button span:after {
  content: '\00bb';
  position: absolute;
  opacity: 0;
  top: 0;
  right: -20px;
  transition: 0.5s;
}

.button:hover span {
  padding-right: 25px;
}

.button:hover span:after {
  opacity: 1;
  right: 0;
}