.jumbotron {
  background-image: url('img/background.jpg');
  background-repeat: no-repeat;
  background-position: center; 
  background-size: cover;
  -webkit-background-size: cover;
  -moz-background-size: cover;
  -o-background-size: cover;
  color: white;
  text-shadow: 2px 2px 6px #000;
}

.course {
  width: 200px;
  height: 300px;
  display: inline-block;
  vertical-align: top;
  background-color: #ddd;
  margin: 15px;
  padding: 15px;
  overflow: hidden;
  text-overflow: ellipsis;
  position: relative; 
}

.course::after {
  content: '';
  position: absolute;
  bottom: 0;
  left:0;
  width: 100%;
  height: 25px;
  background: -webkit-linear-gradient(
          rgba(208, 208, 208, 0) 0%,
          rgba(208, 208, 208, 1) 100%
  );
  background-image: -moz-linear-gradient(
          rgba(208, 208, 208, 0) 0%,
          rgba(208, 208, 208, 1) 100%
  );
  background-image: -o-linear-gradient(
          rgba(208, 208, 208, 0) 0%,
          rgba(208, 208, 208, 1) 100%
  );
  background-image: linear-gradient(
          rgba(208, 208, 208, 0) 0%,
          rgba(208, 208, 208, 1) 100%
  );
  background-image: -ms-linear-gradient(
          rgba(208, 208, 208, 0) 0%,
          rgba(208, 208, 208, 1) 100%
  );
}