html,
body {
  height: 100%;
  min-height: 100%;
}
body {
  font-family: sans-serif;
  text-align: center;
  background-color: #f3e9dc;
  color: #273123;
  display: flex;
  flex-direction: column;
  align-items: center;
  justify-content: center;
  font-size: 16px;
}
header {
  margin-bottom: auto;
  padding-top: 4rem;
}
footer {
  margin-top: auto;
  padding-bottom: 4rem;
  color: #919a8e;
}
h1 {
  margin-top: 0;
  font-weight: 300;
}
#gallery {
  overflow: scroll;
  background: rgba(0, 0, 0, 0.8);
  color: white;
  width: 100%;
  height: 100%;
  z-index: 100;
  top: 0;
  left: 0;
  position: fixed;
  padding: 5rem;
}
#gallery img {
  max-width: 480px;
  width: 100%;
  height: auto;
  margin-bottom: 1rem auto;
}