:root {
  --primary-color: #0f0c29;
  --secondary-color: #302b63;
  --accent-color: #ff8c00;
  --text-color: #e6e6e6;
  --card-bg: #1a1a2e;
  --highlight: #00d4ff;
}

body {
  font-family: 'Montserrat', sans-serif;
  background: linear-gradient(135deg, var(--primary-color), var(--secondary-color));
  color: var(--text-color);
  line-height: 1.6;
  margin: 0;
  padding: 0;
}

.header {
  text-align: center;
  padding: 3rem 2rem;
  background: rgba(15, 12, 41, 0.8);
  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-weight: 700;
  margin-top: 2rem;
  color: white;
}

h1 {
  font-size: 2.5rem;
  background: linear-gradient(90deg, var(--highlight), var(--accent-color));
  -webkit-background-clip: text;
  background-clip: text;
  color: transparent;
  margin-bottom: 1rem;
}

h2 {
  font-size: 1.9rem;
  border-bottom: 2px solid var(--accent-color);
  padding-bottom: 0.5rem;
  display: inline-block;
}

h3 {
  font-size: 1.6rem;
  color: var(--highlight);
}

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

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

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

.card {
  background: var(--card-bg);
  border-radius: 12px;
  padding: 2rem;
  box-shadow: 0 10px 20px rgba(0, 0, 0, 0.2);
  transition: all 0.3s ease;
  position: relative;
  overflow: hidden;
}

.card:hover {
  transform: translateY(-10px);
  box-shadow: 0 15px 30px rgba(0, 0, 0, 0.3);
}

.card::after {
  content: '';
  position: absolute;
  top: 0;
  left: 0;
  width: 100%;
  height: 5px;
  background: linear-gradient(90deg, var(--highlight), var(--accent-color));
}

.code-block {
  background: #24243e;
  border-radius: 8px;
  padding: 1.5rem;
  margin: 2rem 0;
  overflow-x: auto;
  box-shadow: inset 0 0 10px rgba(0, 0, 0, 0.5);
}

code {
  font-family: 'Courier New', monospace;
  color: #00d4ff;
  font-size: 0.9rem;
}

pre {
  margin: 0;
}

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

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

.gallery-img:hover {
  transform: scale(1.05);
  box-shadow: 0 8px 25px rgba(0, 212, 255, 0.3);
}

.note {
  background: rgba(0, 212, 255, 0.1);
  border-left: 4px solid var(--highlight);
  padding: 1rem;
  margin: 2rem 0;
  border-radius: 0 8px 8px 0;
}

.footer {
  text-align: center;
  padding: 2rem;
  margin-top: 3rem;
  background: rgba(15, 12, 41, 0.8);
  position: relative;
}

.footer::before {
  content: '';
  position: absolute;
  top: 0;
  left: 0;
  width: 100%;
  height: 100%;
  background: url('https://images.gptkong.com/demo/sample12.png') center/cover no-repeat;
  opacity: 0.1;
  z-index: -1;
}

@media (max-width: 768px) {
  .grid-system {
    grid-template-columns: 1fr;
  }
  
  h1 {
    font-size: 2rem;
  }
  
  h2 {
    font-size: 1.6rem;
  }
  
  h3 {
    font-size: 1.3rem;
  }
}

@keyframes float {
  0%, 100% {
    transform: translateY(0);
  }
  50% {
    transform: translateY(-20px);
  }
}

.floating {
  animation: float 6s ease-in-out infinite;
}

.pulse {
  animation: pulse 2s infinite;
}

@keyframes pulse {
  0% {
    box-shadow: 0 0 0 0 rgba(0, 212, 255, 0.4);
  }
  70% {
    box-shadow: 0 0 0 10px rgba(0, 212, 255, 0);
  }
  100% {
    box-shadow: 0 0 0 0 rgba(0, 212, 255, 0);
  }
}

.nav-tabs {
  display: flex;
  gap: 1rem;
  margin: 2rem 0;
  flex-wrap: wrap;
}

.nav-tab {
  padding: 0.8rem 1.5rem;
  background: var(--card-bg);
  border-radius: 30px;
  cursor: pointer;
  transition: all 0.3s ease;
  font-weight: 600;
}

.nav-tab:hover {
  background: var(--highlight);
  color: var(--primary-color);
}

.nav-tab.active {
  background: var(--accent-color);
  color: white;
}

.color-swatch {
  display: inline-block;
  width: 20px;
  height: 20px;
  border-radius: 50%;
  margin-right: 5px;
  vertical-align: middle;
}