.img-responsive {
  /*max-width: 100%; */
  max-height: 100%;
  display: block; 
  margin: auto;
}
/*
.img-responsive {
  max-width: 100%; 
  max-height: 100%;
  display: block; 
  margin: auto;
}
*/

.modal {
  text-align: center;
  vertical-align: middle;
  content: " ";
  height: 100%;
  max-height: 100%;
  margin: auto;
}

.carousel-inner>.item>a>img, .carousel-inner>.item>img, .img-responsive, .thumbnail a>img, .thumbnail>img {
    display: block;
    max-width: 50%;
    height: auto;
}

.helper {
    display: inline-block;
    vertical-align: middle;
}
/*
#bootstrap

text-align: center;
*/