.ro {
  background-color: #FFF;
  background-image: url("../images/ro.png");
  background-repeat: no-repeat;
  width: 3%;
  background-position: top left;
}

.rechts {
  background-color: #FFF;
  background-image: url("../images/rechts.png");
  background-repeat: repeat-y;
  background-position: top left;
}

.lu {
  background-image: url("../images/lu.png");
  background-repeat: no-repeat;
  background-position: top left;
  width: 10%;
  height: 22px;
}

.unten {
  background-image: url("../images/unten.png");
  background-repeat: repeat-x;
  background-position: top left;
  width: 87%;
}

.ru {
  background-image: url("../images/ru.png");
  background-repeat: no-repeat;
  background-position: top left;
}