body, html {
  width: 100%;
  height: 100%;
  background-image: url("../img/background/photos.jpg");
  background-attachment: fixed;
  background-position: center center;
  background-size: cover;
  background-repeat: no-repeat;
}

.galerie-box {
  position: relative;
  display: block;
  max-width: 650px;
  margin: 0 auto;
}
.galerie-box:focus {
  outline: none;
}