header {
background: #8888;
margin-left: auto;
margin-right: auto;
width: 50%;
text-align: center;
}



p {
width: 50%;
margin-left: auto;
margin-right: auto;
text-align: center;
}


form {
background: #8888;
width: 50%;
margin-left: auto;
margin-right: auto;
text-align: center;
}


table, th, td {
  border:1px solid black;
}