:root {
  --primary: #181E2C;
  --secondary: #1E273C;
  --accent: #03A9F4;
  --highlight: #34C759;
  --text: #FFFFFF;
  --shadow: 0 4px 20px rgba(0, 0, 0, 0.3);
}

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

body {
  background: linear-gradient(135deg, var(--primary), #000000);
  color: var(--text);
  font-family: 'Roboto', sans-serif;
  line-height: 1.6;
  padding-top: 80px;
}

.container {
  max-width: 1200px;
  margin: 0 auto;
  padding: 0 20px;
}

.header {
  position: fixed;
  top: 0;
  left: 0;
  width: 100%;
  background: rgba(24, 30, 44, 0.95);
  backdrop-filter: blur(10px);
  z-index: 1000;
  padding: 15px 0;
  box-shadow: var(--shadow);
}

.nav {
  display: flex;
  justify-content: space-between;
  align-items: center;
  max-width: 1200px;
  margin: 0 auto;
  padding: 0 20px;
}

.logo {
  font-size: 1.5rem;
  font-weight: 700;
  color: var(--accent);
  text-decoration: none;
}

.nav-links {
  display: flex;
  gap: 30px;
}

.nav-links a {
  color: var(--text);
  text-decoration: none;
  font-weight: 500;
  transition: color 0.3s;
  position: relative;
}

.nav-links a:hover {
  color: var(--accent);
}

.nav-links a::after {
  content: '';
  position: absolute;
  bottom: -5px;
  left: 0;
  width: 0;
  height: 2px;
  background: var(--accent);
  transition: width 0.3s;
}

.nav-links a:hover::after {
  width: 100%;
}

.hero {
  height: 500px;
  display: flex;
  align-items: center;
  position: relative;
  overflow: hidden;
  margin-bottom: 60px;
}

.hero::before {
  content: '';
  position: absolute;
  top: 0;
  left: 0;
  width: 100%;
  height: 100%;
  background: radial-gradient(circle at 70% 30%, rgba(3, 169, 244, 0.1), transparent 70%);
}

.hero-content {
  position: relative;
  z-index: 1;
  max-width: 600px;
}

.hero h1 {
  font-size: 3rem;
  margin-bottom: 20px;
  background: linear-gradient(90deg, var(--accent), var(--highlight));
  -webkit-background-clip: text;
  background-clip: text;
  color: transparent;
}

.hero p {
  font-size: 1.2rem;
  margin-bottom: 30px;
  opacity: 0.9;
}

.hero-img {
  position: absolute;
  right: 0;
  top: 50%;
  transform: translateY(-50%);
  width: 500px;
  height: 400px;
  background: url('https://images.gptkong.com/demo/sample1.png') no-repeat center/contain;
  opacity: 0.8;
}

.section {
  margin-bottom: 80px;
}

.section-title {
  font-size: 2rem;
  margin-bottom: 40px;
  position: relative;
  display: inline-block;
}

.section-title::after {
  content: '';
  position: absolute;
  bottom: -10px;
  left: 0;
  width: 50px;
  height: 3px;
  background: var(--accent);
}

.grid {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(300px, 1fr));
  gap: 30px;
}

.card {
  background: var(--secondary);
  border-radius: 15px;
  padding: 30px;
  box-shadow: var(--shadow);
  transition: transform 0.3s, box-shadow 0.3s;
  position: relative;
  overflow: hidden;
}

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

.card:hover {
  transform: translateY(-10px);
  box-shadow: 0 10px 30px rgba(0, 0, 0, 0.4);
}

.card-img {
  width: 100%;
  height: 200px;
  object-fit: cover;
  border-radius: 10px;
  margin-bottom: 20px;
  box-shadow: 0 5px 15px rgba(0, 0, 0, 0.2);
}

.card-title {
  font-size: 1.5rem;
  margin-bottom: 15px;
  color: var(--accent);
}

.card-content {
  margin-bottom: 20px;
}

.btn {
  display: inline-block;
  padding: 12px 25px;
  background: linear-gradient(90deg, var(--accent), var(--highlight));
  color: white;
  border: none;
  border-radius: 30px;
  font-weight: 600;
  cursor: pointer;
  transition: transform 0.3s, box-shadow 0.3s;
  text-decoration: none;
}

.btn:hover {
  transform: translateY(-3px);
  box-shadow: 0 10px 20px rgba(3, 169, 244, 0.3);
}

.features {
  display: flex;
  flex-wrap: wrap;
  gap: 30px;
  margin-bottom: 60px;
}

.feature {
  flex: 1;
  min-width: 300px;
  background: var(--secondary);
  padding: 30px;
  border-radius: 15px;
  box-shadow: var(--shadow);
  position: relative;
  overflow: hidden;
}

.feature::before {
  content: '';
  position: absolute;
  top: 0;
  left: 0;
  width: 5px;
  height: 100%;
  background: linear-gradient(to bottom, var(--accent), var(--highlight));
}

.feature-icon {
  font-size: 2.5rem;
  margin-bottom: 20px;
  color: var(--accent);
}

.feature-title {
  font-size: 1.5rem;
  margin-bottom: 15px;
}

.feature-content {
  opacity: 0.9;
}

.article {
  background: var(--secondary);
  border-radius: 15px;
  padding: 40px;
  box-shadow: var(--shadow);
  margin-bottom: 60px;
}

.article h2 {
  font-size: 2rem;
  margin-bottom: 30px;
  color: var(--accent);
}

.article h3 {
  font-size: 1.5rem;
  margin: 30px 0 20px;
  color: var(--highlight);
}

.article p {
  margin-bottom: 20px;
  line-height: 1.8;
}

pre {
  background: #252A3C;
  border-radius: 10px;
  padding: 20px;
  margin: 20px 0;
  overflow-x: auto;
  box-shadow: inset 0 0 10px rgba(0, 0, 0, 0.5);
}

code {
  font-family: 'Courier New', monospace;
  color: var(--highlight);
}

.footer {
  background: var(--primary);
  padding: 50px 0;
  text-align: center;
}

.footer p {
  opacity: 0.7;
}

.notice {
  background: rgba(52, 199, 89, 0.1);
  border-left: 5px solid var(--highlight);
  padding: 20px;
  margin: 40px 0;
  border-radius: 0 5px 5px 0;
}

.notice p {
  margin: 0;
}

@media (max-width: 992px) {
  .hero {
    height: auto;
    padding: 100px 0;
  }
  
  .hero-img {
    display: none;
  }
  
  .hero-content {
    max-width: 100%;
  }
}

@media (max-width: 768px) {
  .nav-links {
    display: none;
  }
  
  .hero h1 {
    font-size: 2.5rem;
  }
  
  .section-title {
    font-size: 1.8rem;
  }
}

@media (max-width: 576px) {
  .hero h1 {
    font-size: 2rem;
  }
  
  .card, .feature {
    min-width: 100%;
  }
  
  .article {
    padding: 30px 20px;
  }
}

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

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

@keyframes pulse {
  0%, 100% {
    opacity: 1;
  }
  50% {
    opacity: 0.5;
  }
}

.pulse {
  animation: pulse 2s ease-in-out infinite;
}

.geometric-shape {
  width: 200px;
  height: 200px;
  background: var(--accent);
  clip-path: polygon(50% 0%, 100% 50%, 50% 100%, 0% 50%);
  position: absolute;
  opacity: 0.1;
  z-index: 0;
}

.shape-1 {
  top: 20%;
  left: 10%;
  animation: float 8s ease-in-out infinite;
}

.shape-2 {
  bottom: 15%;
  right: 10%;
  animation: float 7s ease-in-out infinite reverse;
}

.shape-3 {
  top: 50%;
  left: 50%;
  transform: translate(-50%, -50%);
  animation: pulse 5s ease-in-out infinite;
}