body {
  margin: 10px;
  font-size: 15px;
  font-family: 'Ubuntu', arial, serif;
}

#header {
  border-bottom: 3px solid red;
}

#content {
  margin-top: 25px;
}

#footer {
  margin-top: 25px;
}

.center {
  text-align: center;
}