.box{
  width: 100%;
  height: auto;
  background: #CCC;
  overflow: hidden;
}
.box img{
  width: 100%;
  height: auto;
}
.slider-et4{
  /* Full height */
  height: 100%; 
  max-width: 100%;
  max-height: 100%;
  /* Center and scale the image nicely */
  background-position: center;
  background-repeat: no-repeat;
  background-size: cover;
}
.carousel-inner{
  width: 100%;
  height: 100%; 
}