html {
  font-family: Helvetica, Verdana, serif;
  font-size: 18px;
}

.big_photo {
  display: flex;
  align-items: center;
  justify-content: center;
  margin-bottom: 5vh;
  /* min-height: 100vh; */ /* this helps ensure each photo gets a full screen's height. */
}

img {
  max-height: 90vh; /* reveals the next photo below the fold.  or to get fuller-screen: calc(100vh  - 100px) */
  /* width: auto; */
  max-width: 90vw;
  border-radius: 4px;
}

nav.photo-nav {
  font-size: 1.1rem;
  margin: 0.5em 0 1em;
}

nav.photo-nav a {
  text-decoration: none;
  color: inherit;
  padding: 4px;
}

.nav-selected {
  background-color: #FFF5D9;
  border-radius: 4px;
}

.photo_info {
  max-width: 600px;
  margin: 1em auto 1em auto;
  font-weight: lighter;
}

.photo_thumb_section {
  display: flex;
  flex-wrap: wrap;
  max-width: calc(310px * 3 + 20px * 2);
  margin-left: auto;
  margin-right: auto;
}
.photo_thumb img {
  max-width: 300px;
  margin-right: 20px;
  margin-bottom: 0;
}

.photo-caption {
  max-width: 300px;
  margin: 0.25rem 20px 1.5rem 0;
  font-size: 1rem;
  line-height: 1.4;
}

.photo_thumb .photo-caption {
  width: 300px;
}

.photo-pagination {
  display: flex;
  justify-content: space-between;
  gap: 1rem;
  font-size: 1rem;
}