body {
  padding-top: 50px;
  background:#000 url("../img/bitraum_start_back.jpg") no-repeat fixed center top;
}
.content-wrapper {
  padding: 40px 15px;
}

.inner-content {
  margin-top: 300px;
  -ms-filter: "progid:DXImageTransform.Microsoft.Alpha(Opacity=80)";       /* IE 8 */
  filter: alpha(opacity=80);  /* IE 5-7 */
  -moz-opacity: 0.8;          /* Netscape */
  -khtml-opacity: 0.8;        /* Safari 1.x */
  opacity: 0.8;               /* Good browsers */
  min-height: 350px;
}