body {
  margin: 0;
  font-family: 'Segoe UI', 'Roboto', Arial, sans-serif;
  background: #f7f7f9;
  color: #222;
}
header {
  background: #fff;
  box-shadow: 0 2px 8px rgba(0,0,0,0.04);
  padding: 1rem 0;
  margin-bottom: 2rem;
}
header h1 {
  margin: 0;
  text-align: center;
  font-size: 2rem;
  letter-spacing: 2px;
}
nav {
  display: flex;
  justify-content: center;
  gap: 2rem;
  margin-top: 0.5rem;
}
nav a {
  text-decoration: none;
  color: #2a4d69;
  font-weight: 500;
  padding: 0.25rem 0.5rem;
  border-radius: 4px;
  transition: background 0.2s;
}
nav a:hover {
  background: #e7eaf6;
}
main {
  max-width: 900px;
  margin: 0 auto;
  padding: 1rem;
  background: #fff;
  border-radius: 8px;
  box-shadow: 0 2px 8px rgba(0,0,0,0.03);
}
.main-image {
  width: 100%;
  max-height: 350px;
  object-fit: cover;
  object-position: top;
  border-radius: 8px;
  margin-bottom: 1.5rem;
}
.highlights ul {
  list-style: disc inside;
  padding-left: 1rem;
}
.highlights li {
  margin-bottom: 0.5rem;
}
.diagram-gallery {
  display: flex;
  flex-wrap: wrap;
  gap: 2rem;
  justify-content: center;
}
.diagram-gallery figure {
  margin: 0;
  text-align: center;
}
.diagram-gallery img {
  max-width: 350px;
  width: 100%;
  border-radius: 8px;
  box-shadow: 0 2px 8px rgba(0,0,0,0.07);
}
.gallery {
  display: flex;
  flex-wrap: wrap;
  gap: 1rem;
  justify-content: center;
  margin-bottom: 2rem;
}
.gallery img {
  width: 200px;
  height: 140px;
  object-fit: cover;
  border-radius: 6px;
  box-shadow: 0 2px 8px rgba(0,0,0,0.06);
}
.contact {
  margin-top: 2rem;
  padding: 1rem;
  background: #e7eaf6;
  border-radius: 6px;
  max-width: 400px;
}
footer {
  text-align: center;
  margin: 2rem 0 1rem 0;
  color: #888;
  font-size: 0.95rem;
}
.clickable {
  cursor: pointer;
  transition: box-shadow 0.2s, transform 0.2s;
}
.clickable:hover {
  box-shadow: 0 4px 16px rgba(42,77,105,0.15);
  transform: scale(1.03);
}
.modal {
  display: none;
  position: fixed;
  z-index: 1000;
  left: 0;
  top: 0;
  width: 100vw;
  height: 100vh;
  overflow: auto;
  background-color: rgba(0,0,0,0.85);
  align-items: center;
  justify-content: center;
}
.modal-content {
  margin: auto;
  display: block;
  max-width: 90vw;
  max-height: 90vh;
  border-radius: 8px;
  box-shadow: 0 4px 32px rgba(0,0,0,0.25);
}
.close {
  position: absolute;
  top: 30px;
  right: 50px;
  color: #fff;
  font-size: 2.5rem;
  font-weight: bold;
  cursor: pointer;
  z-index: 1001;
  text-shadow: 0 2px 8px #000;
}
@media (max-width: 600px) {
  main {
    padding: 0.5rem;
  }
  .diagram-gallery {
    flex-direction: column;
    gap: 1rem;
  }
  .gallery img {
    width: 100%;
    height: 120px;
  }
  .close {
    top: 10px;
    right: 20px;
    font-size: 2rem;
  }
}