body {
  background-image: url('doc.png');
  background-position: center;
  background-size: cover;
}
.container{
  width:60%;
  box-shadow: 0 -1px 10px rgba(0, 0, 0, 0.1);
  margin-top: 25px;
  margin-bottom: 25px;
  border-radius: 1em;
  background: rgba(255,255,255,0.9);
}
@media screen and (max-width: 40em) {
  .display-4{
    font-size: 1.5em;
  }
  .container{
    width: 80%
  }
}