.masthead {
  height: 100vh;
  background-color: #000;
  -webkit-background-size: cover;
  -moz-background-size: cover;
  -o-background-size: cover;
  background-size: cover;
  background-position: center;
  background-repeat: no-repeat;
}
.masthead img {
  margin-bottom: 20px;
  padding: 0 20px;
  width: 100%;
  max-width: 500px;
}