* { margin: 0; padding: 0; border: none }
html { height: 100%; overflow-y: scroll }
body { display: table; width: 100%; height: 100%; min-height: 100% }

#main { display: table-row; min-height: 100%; height: 100%; }

.center {
  display: block;
  margin-left: auto;
  margin-right: auto;
}