html,body{
  height: 100%;
  width: 100%;
  margin: 0;
  font-size: 14pt;
  font-family: Arial, Helvetica, sans-serif;

}

.zentriert {
  position: fixed;
  top: 50%;
  left: 50%;
  /* bring your own prefixes */
  transform: translate(-50%, -50%);
}

table {
  width: 100 %;
  margin: 0 auto;
}