body {
  background-color: #f0f0f0;
  color: #000;
  font-family: 'Courier New', Courier, monospace;
  margin: 0;
  padding: 0;
}

#container {
  width: 800px;
  margin: 0 auto;
  background-color: #fff;
  border: 1px solid #000;
  padding: 20px;
}

.nav {
  cursor: pointer;
  padding: 4px 12px;
  margin: 0 5px;
  border: 1px solid #000;
  background-color: #eee;
  font-weight: bold;
  display: inline-block;
  user-select: none;
}

.nav:hover {
  background-color: #ccc;
}
.gallery-grid img {
  width: 100%;
  aspect-ratio: 4 / 3;
  object-fit: cover;
  cursor: pointer;
}