body, html {
  height: 100%;
  margin: 0;
}

.bg {
  background-image: url("hintergrund.jpeg");
  height: 100%;
  background-position: center;
  background-repeat: no-repeat;
  background-size: cover;
  opacity: 0.85;
}

.caption {
    position: absolute;
    left: 0;
    top: 80%;
    width: 100%;
    text-align: center;
    color: #000;
}
/*
.border{
    background-color: #111;
    color: #fff;
    padding: 18px;
    font-size: 25px;
    letter-spacing: 10px;
}
*/

img {
  width: 50%;
  height: auto;
  border-radius: 20px;
}

@media (min-width:800px) {
  img {
    width: 25%;
  }