*{
	padding: 0;
	margin: 0;
}
body{
	font-family: Arial, Helvetica, sans-serif;
	background-color: #eee;
}
#header{
	background: black;
	padding: 10px;
}
.lista {
  padding: 0;
  margin: 0;
  list-style-type: none;
  display: flex;
  justify-content: space-around;
  align-items: center;
}
.lista a:hover{
	background: white;
	color: black;
}
.lista li {
  padding: 5px;
}
.lista a{
	color: white;
	text-decoration: none;
	padding: 10px;
}

@media (max-width: 767px) {
  .lista {
    flex-direction: column;
  }

  .lista li {
    text-align: center;
  }
}


#footer{
	background-color: #ccc;
	padding: 20px;
}

#main{
	padding: 2em 0;
	width: 500px;
	margin: 0 auto;
}
.center{
	text-align: center;
}
.error{
	color: red;
}