:root {
  --retro-orange: #FF7F50;
  --tech-blue: #005f99;
  --dark-bg: #1a1a2e;
  --light-bg: rgba(255, 255, 255, 0.1);
  --accent-purple: #6a0dad;
  --text-light: #f8f9fa;
  --text-dim: #adb5bd;
}

body {
  font-family: 'Courier New', monospace, sans-serif;
  background: linear-gradient(135deg, var(--dark-bg) 0%, #16213e 100%);
  color: var(--text-light);
  line-height: 1.6;
  margin: 0;
  padding: 0;
  min-height: 100%;
}

.header {
  text-align: center;
  padding: 3rem 1rem;
  background: linear-gradient(to right, rgba(106, 13, 173, 0.3), rgba(0, 95, 153, 0.3));
  position: relative;
  overflow: hidden;
}

.header::before {
  content: '';
  position: absolute;
  top: 0;
  left: 0;
  width: 100%;
  height: 100%;
  background: url('https://images.gptkong.com/demo/sample1.png') center/cover no-repeat;
  opacity: 0.2;
  z-index: -1;
}

h1, h2, h3, h4 {
  font-family: 'Orbitron', sans-serif;
  font-weight: 500;
  letter-spacing: 1px;
}

h1 {
  font-size: 2.5rem;
  margin-bottom: 1rem;
  color: var(--retro-orange);
  text-shadow: 0 0 10px rgba(255, 127, 80, 0.5);
}

h2 {
  font-size: 1.8rem;
  color: var(--tech-blue);
  border-left: 4px solid var(--retro-orange);
  padding-left: 1rem;
  margin: 2.5rem 0 1.5rem;
}

h3 {
  font-size: 1.5rem;
  color: var(--text-light);
  margin: 2rem 0 1rem;
}

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

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

.grid {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(500px, 1fr));
  gap: 2rem;
  margin: 3rem 0;
}

.card {
  background: var(--light-bg);
  border-radius: 12px;
  padding: 2rem;
  backdrop-filter: blur(10px);
  border: 1px solid rgba(255, 255, 255, 0.1);
  box-shadow: 0 10px 30px rgba(0, 0, 0, 0.3);
  transition: all 0.3s ease;
}

.card:hover {
  transform: translateY(-5px);
  box-shadow: 0 15px 35px rgba(0, 0, 0, 0.4);
}

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

.img-container img {
  width: 150px;
  height: 150px;
  object-fit: cover;
  border-radius: 8px;
  box-shadow: 0 5px 15px rgba(0, 0, 0, 0.2);
  transition: all 0.3s ease;
  filter: grayscale(30%);
}

.img-container img:hover {
  transform: scale(1.05);
  filter: grayscale(0%);
  box-shadow: 0 8px 25px rgba(0, 95, 153, 0.4);
}

pre {
  background: rgba(0, 0, 0, 0.3);
  border-left: 4px solid var(--accent-purple);
  border-radius: 0 8px 8px 0;
  padding: 1.5rem;
  overflow-x: auto;
  font-family: 'Courier New', monospace;
  font-size: 0.95rem;
  line-height: 1.5;
  margin: 2rem 0;
  position: relative;
}

pre::before {
  content: 'CSS';
  position: absolute;
  top: 0;
  right: 0;
  background: var(--accent-purple);
  color: white;
  padding: 0.2rem 0.8rem;
  font-size: 0.8rem;
  border-radius: 0 0 0 8px;
}

.navbar {
  display: flex;
  justify-content: center;
  background: rgba(26, 26, 46, 0.9);
  padding: 1rem;
  position: sticky;
  top: 0;
  z-index: 1000;
  backdrop-filter: blur(10px);
  border-bottom: 1px solid rgba(255, 127, 80, 0.3);
}

.nav-link {
  color: var(--text-dim);
  text-decoration: none;
  padding: 0.5rem 1.5rem;
  margin: 0 0.5rem;
  position: relative;
  transition: all 0.3s ease;
  font-family: 'Orbitron', sans-serif;
}

.nav-link:hover {
  color: var(--retro-orange);
}

.nav-link::after {
  content: '';
  position: absolute;
  bottom: 0;
  left: 50%;
  width: 0;
  height: 2px;
  background: var(--retro-orange);
  transition: all 0.3s ease;
}

.nav-link:hover::after {
  width: 100%;
  left: 0;
}

.footer {
  text-align: center;
  padding: 2rem;
  background: rgba(26, 26, 46, 0.8);
  margin-top: 3rem;
  border-top: 1px solid rgba(255, 127, 80, 0.3);
}

.notice {
  background: rgba(255, 127, 80, 0.2);
  border-left: 4px solid var(--retro-orange);
  padding: 1rem;
  margin: 2rem 0;
  border-radius: 0 8px 8px 0;
}

@media (max-width: 768px) {
  .grid {
    grid-template-columns: 1fr;
  }
  
  .header {
    padding: 2rem 1rem;
  }
  
  h1 {
    font-size: 2rem;
  }
  
  .img-container img {
    width: 120px;
    height: 120px;
  }
}

@keyframes pulse {
  0% { opacity: 0.6; }
  50% { opacity: 1; }
  100% { opacity: 0.6; }
}

.pulse {
  animation: pulse 2s infinite;
}