* {
  box-sizing: border-box;
}

body {
  min-height: 100vh;
  background-image: url(../img/to_the_moon_big.jpg);
  background-position: center;
  background-size: cover;
}

.header {
  height: 10vh;
}

#intro {
  position: relative;
  width: 615px;
  margin-left: 8vw;
  color: #DDD;
  font-family: "Helvetica", "Arial", sans-serif;
  line-height: 1.4em;
  background-color: rgba(66, 66, 66, 0.6);
  padding: 0.1em 1em 1em 1em;
  border-radius: 10px;
}

.download a {
  display: block;
  position: relative;
  width: 8em;
  left: 70%;
  text-decoration: none;
  color: #424242;
  line-height: 3em;
  background-color: lightblue;
  border-radius: 5px;
  text-align: center;
}

@media screen and (max-width: 1024px) {
  .header {
    height: 20vh;
  }
}

@media screen and (max-width: 767px) {
  .header {
    height: 20vh;
  }

  #intro {
    width: 90%;
    margin-left: 5vw;
    margin-bottom: 10vh;
  }

  .download a {
    left: 40%;
  }
}

@media screen and (max-width: 479px) {
  .header {
    height: 15vh;
  }
}