:root {
  --retro-brown: #8B5E3C;
  --retro-beige: #F5F5DC;
  --olive-green: #556B2F;
  --tech-blue: #1E3A5F;
  --violet: #8A2BE2;
  --highlight-gold: #FFD700;
  --highlight-lightblue: #ADD8E6;
  --shadow-color: rgba(0,0,0,0.15);
}

* {
  margin: 0;
  padding: 0;
  box-sizing: border-box;
}

body {
  background: linear-gradient(135deg, var(--retro-beige) 0%, #f0e6cc 100%);
  color: var(--retro-brown);
  font-family: 'Helvetica Neue', Arial, sans-serif;
  line-height: 1.6;
  padding: 0;
  margin: 0;
  min-height: 100%;
  overflow-x: hidden;
}

header {
  background: linear-gradient(to right, var(--retro-brown), var(--olive-green));
  padding: 2rem 0;
  text-align: center;
  position: relative;
  overflow: hidden;
  box-shadow: 0 4px 12px var(--shadow-color);
}

header::before {
  content: "";
  position: absolute;
  top: 0;
  left: 0;
  right: 0;
  height: 4px;
  background: linear-gradient(90deg, var(--highlight-gold), var(--highlight-lightblue));
}

.header-content {
  max-width: 1200px;
  margin: 0 auto;
  padding: 0 2rem;
  position: relative;
  z-index: 2;
}

h1, h2, h3, h4 {
  font-family: 'Times New Roman', serif;
  color: var(--tech-blue);
  margin-bottom: 1.5rem;
  position: relative;
}

h1 {
  font-size: 2.5rem;
  line-height: 1.2;
  margin-bottom: 1rem;
}

h2 {
  font-size: 2rem;
  padding-bottom: 0.5rem;
  border-bottom: 2px solid var(--highlight-gold);
}

h3 {
  font-size: 1.5rem;
  color: var(--olive-green);
}

p {
  margin-bottom: 1.5rem;
  font-size: 1.1rem;
}

.container {
  max-width: 1200px;
  margin: 0 auto;
  padding: 2rem;
}

.grid {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(300px, 1fr));
  gap: 2rem;
  margin: 3rem 0;
}

.card {
  background: white;
  border-radius: 12px;
  overflow: hidden;
  box-shadow: 0 8px 24px rgba(0,0,0,0.1);
  transition: transform 0.3s ease, box-shadow 0.3s ease;
  position: relative;
}

.card:hover {
  transform: translateY(-5px);
  box-shadow: 0 12px 28px rgba(0,0,0,0.15);
}

.card-img {
  width: 100%;
  height: 200px;
  object-fit: cover;
  border-bottom: 1px solid rgba(0,0,0,0.1);
}

.card-content {
  padding: 1.5rem;
}

.button {
  display: inline-block;
  padding: 0.8rem 1.8rem;
  background: linear-gradient(45deg, var(--highlight-gold), var(--highlight-lightblue));
  color: white;
  border-radius: 50px;
  text-decoration: none;
  font-weight: bold;
  transition: all 0.3s ease;
  box-shadow: 0 4px 8px rgba(0,0,0,0.1);
  border: none;
  cursor: pointer;
  margin: 1rem 0;
}

.button:hover {
  background: linear-gradient(45deg, var(--highlight-lightblue), var(--highlight-gold));
  box-shadow: 0 6px 12px rgba(0,0,0,0.15);
  transform: translateY(-2px);
}

.code-container {
  background: #2d2d2d;
  border-radius: 8px;
  padding: 1.5rem;
  margin: 2rem 0;
  overflow: auto;
  box-shadow: inset 0 0 10px rgba(0,0,0,0.5);
}

pre {
  margin: 0;
  white-space: pre-wrap;
  font-family: 'Courier New', monospace;
  color: #f8f8f2;
  line-height: 1.5;
  font-size: 0.95rem;
}

.highlight {
  background: rgba(255,215,0,0.1);
  padding: 0.2rem 0.4rem;
  border-radius: 4px;
  border-left: 3px solid var(--highlight-gold);
}

.note {
  background: rgba(173,216,230,0.1);
  padding: 1rem;
  border-radius: 8px;
  border-left: 4px solid var(--highlight-lightblue);
  margin: 1.5rem 0;
}

.footer {
  background: linear-gradient(to right, var(--retro-brown), var(--olive-green));
  color: white;
  text-align: center;
  padding: 2rem;
  margin-top: 3rem;
}

@media (max-width: 768px) {
  .grid {
    grid-template-columns: 1fr;
  }
  
  h1 {
    font-size: 2rem;
  }
  
  h2 {
    font-size: 1.75rem;
  }
  
  .container {
    padding: 1.5rem;
  }
}

@keyframes float {
  0% { transform: translateY(0px); }
  50% { transform: translateY(-10px); }
  100% { transform: translateY(0px); }
}

.floating {
  animation: float 3s ease-in-out infinite;
}

.decorative-line {
  height: 2px;
  background: linear-gradient(90deg, transparent, var(--highlight-gold), transparent);
  margin: 2rem 0;
}

.image-gallery {
  display: flex;
  flex-wrap: wrap;
  gap: 1rem;
  justify-content: center;
  margin: 2rem 0;
}

.gallery-img {
  width: 150px;
  height: 150px;
  object-fit: cover;
  border-radius: 8px;
  box-shadow: 0 4px 8px rgba(0,0,0,0.1);
  transition: all 0.3s ease;
}

.gallery-img:hover {
  transform: scale(1.05);
  box-shadow: 0 8px 16px rgba(0,0,0,0.15);
}

.section {
  margin-bottom: 4rem;
  padding: 2rem;
  background: rgba(255,255,255,0.8);
  border-radius: 12px;
  box-shadow: 0 4px 12px rgba(0,0,0,0.05);
}

.reference-note {
  position: fixed;
  bottom: 20px;
  right: 20px;
  background: white;
  padding: 10px 15px;
  border-radius: 50px;
  box-shadow: 0 4px 8px rgba(0,0,0,0.1);
  font-size: 0.9rem;
  z-index: 100;
}