header {
  background: rgba(0, 0, 0, 0.7); /* black tint */
  color: white;
  padding: 1rem;
  text-align: center;
}

header a {
  color: white;
  text-decoration: none;
  margin: 0 1rem;
}

header a:hover {
  text-decoration: underline;
}

h1 {
  text-align: center;
  font-family: Arial, sans-serif;
  font-size: 3rem;
  color: #333;
}
.section1 {
  height: 700px;
  background-image: url("images/section1.jpg");
  background-size: cover;
}
.section2 {
  height: 400px;
  background-image: url("images/section2.jpg");
  background-size: contain;
  background-repeat: no-repeat;
}