body{
  font-family:sans-serif;
  margin:0;
  padding:0;
}
.hint{
  color:red;
}
.center{
  margin:0 30px 0 auto;
  width:60%;
}

input{
  float:left;
  width:50%;
}
input[type="submit"]{
  margin-top:20px;
}

.show{

  display: none;
  visibility: hidden;
  color: white;
}