:root {
  --primary-color: #0074D9;
  --secondary-color: #BDC3C7;
  --background-color: #1A1A1A;
  --accent-color: #6C5CE7;
  --button-color: #FFA500;
  --text-color: #FFFFFF;
  --card-bg: rgba(255, 255, 255, 0.1);
  --transition: all 0.3s cubic-bezier(0.25, 0.8, 0.25, 1);
}

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

body {
  font-family: 'Roboto', sans-serif;
  background: var(--background-color);
  color: var(--text-color);
  line-height: 1.6;
  overflow-x: hidden;
}

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

.header {
  background: linear-gradient(135deg, var(--primary-color) 0%, var(--accent-color) 100%);
  padding: 2rem 0;
  text-align: center;
  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: 0;
}

.header-content {
  position: relative;
  z-index: 1;
}

.header h1 {
  font-size: 3rem;
  margin-bottom: 1rem;
  text-shadow: 0 2px 10px rgba(0, 0, 0, 0.3);
  background: linear-gradient(to right, #fff, var(--secondary-color));
  -webkit-background-clip: text;
  -webkit-text-fill-color: transparent;
}

.notice {
  background: rgba(0, 0, 0, 0.5);
  padding: 1rem;
  border-radius: 8px;
  display: inline-block;
  margin: 2rem auto;
  font-size: 1.2rem;
  border: 1px solid var(--accent-color);
}

.nav {
  display: flex;
  justify-content: center;
  background: rgba(0, 0, 0, 0.7);
  padding: 1rem;
  position: sticky;
  top: 0;
  z-index: 100;
  backdrop-filter: blur(10px);
}

.nav a {
  color: var(--text-color);
  text-decoration: none;
  margin: 0 1.5rem;
  padding: 0.5rem 1rem;
  border-radius: 4px;
  transition: var(--transition);
  font-weight: 500;
}

.nav a:hover {
  background: var(--accent-color);
  transform: translateY(-3px);
}

.main-content {
  padding: 3rem 0;
}

.article {
  background: var(--card-bg);
  border-radius: 16px;
  padding: 2rem;
  margin-bottom: 3rem;
  box-shadow: 0 10px 30px rgba(0, 0, 0, 0.2);
  transition: var(--transition);
}

.article:hover {
  transform: translateY(-5px);
  box-shadow: 0 15px 40px rgba(0, 0, 0, 0.3);
}

.article h2 {
  font-size: 2.2rem;
  margin-bottom: 1.5rem;
  color: var(--secondary-color);
  position: relative;
  padding-bottom: 0.5rem;
}

.article h2::after {
  content: "";
  position: absolute;
  bottom: 0;
  left: 0;
  width: 100px;
  height: 3px;
  background: linear-gradient(to right, var(--primary-color), var(--accent-color));
}

.article h3 {
  font-size: 1.8rem;
  margin: 2rem 0 1rem;
  color: var(--primary-color);
}

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

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

.image-card {
  border-radius: 12px;
  overflow: hidden;
  box-shadow: 0 5px 15px rgba(0, 0, 0, 0.2);
  transition: var(--transition);
  position: relative;
}

.image-card:hover {
  transform: scale(1.03);
  box-shadow: 0 8px 25px rgba(0, 0, 0, 0.3);
}

.image-card img {
  width: 100%;
  height: auto;
  display: block;
  transition: var(--transition);
}

.image-card:hover img {
  transform: scale(1.1);
}

pre {
  background: rgba(0, 0, 0, 0.7);
  border-radius: 8px;
  padding: 1.5rem;
  overflow-x: auto;
  margin: 2rem 0;
  border-left: 4px solid var(--accent-color);
  font-family: 'Courier New', monospace;
  font-size: 0.95rem;
  line-height: 1.5;
}

code {
  color: var(--secondary-color);
  font-family: inherit;
}

table {
  width: 100%;
  border-collapse: collapse;
  margin: 2rem 0;
  background: rgba(0, 0, 0, 0.5);
  border-radius: 8px;
  overflow: hidden;
}

th, td {
  padding: 1rem;
  text-align: left;
  border-bottom: 1px solid rgba(255, 255, 255, 0.1);
}

th {
  background: var(--primary-color);
  color: white;
  font-weight: 500;
}

tr:hover {
  background: rgba(255, 255, 255, 0.05);
}

.footer {
  background: linear-gradient(135deg, var(--accent-color) 0%, var(--primary-color) 100%);
  padding: 3rem 0;
  text-align: center;
  margin-top: 3rem;
}

.footer p {
  margin-bottom: 1rem;
}

.footer-links {
  display: flex;
  justify-content: center;
  flex-wrap: wrap;
  margin-top: 1.5rem;
}

.footer-links a {
  color: var(--text-color);
  margin: 0 1rem;
  text-decoration: none;
  transition: var(--transition);
}

.footer-links a:hover {
  color: var(--button-color);
  transform: translateY(-3px);
}

@media (max-width: 768px) {
  .header h1 {
    font-size: 2.2rem;
  }
  
  .nav {
    flex-wrap: wrap;
  }
  
  .nav a {
    margin: 0.5rem;
  }
  
  .article h2 {
    font-size: 1.8rem;
  }
  
  .article h3 {
    font-size: 1.5rem;
  }
  
  .image-grid {
    grid-template-columns: 1fr;
  }
}

/* Animations */
@keyframes float {
  0%, 100% {
    transform: translateY(0);
  }
  50% {
    transform: translateY(-15px);
  }
}

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

/* 3D Button */
.button-3d {
  background-color: var(--button-color);
  border: none;
  padding: 15px 30px;
  color: #fff;
  font-size: 16px;
  cursor: pointer;
  transition: transform 0.5s, box-shadow 0.5s;
  transform-style: preserve-3d;
  border-radius: 8px;
  margin: 1rem 0;
  display: inline-block;
}

.button-3d:hover {
  transform: rotateY(360deg);
  box-shadow: 0 0 20px var(--button-color);
}

/* Parallax Effect */
.parallax-section {
  height: 400px;
  background-attachment: fixed;
  background-position: center;
  background-repeat: no-repeat;
  background-size: cover;
  position: relative;
  margin: 3rem 0;
  border-radius: 16px;
  overflow: hidden;
}

.parallax-section::before {
  content: "";
  position: absolute;
  top: 0;
  left: 0;
  width: 100%;
  height: 100%;
  background: linear-gradient(to bottom, rgba(0,0,0,0.3), rgba(0,0,0,0.7));
}

.parallax-content {
  position: absolute;
  top: 50%;
  left: 50%;
  transform: translate(-50%, -50%);
  text-align: center;
  width: 80%;
  z-index: 1;
}

/* Theme Toggle */
.theme-toggle {
  position: fixed;
  bottom: 30px;
  right: 30px;
  z-index: 100;
}

.toggle-btn {
  background: var(--accent-color);
  color: white;
  border: none;
  width: 50px;
  height: 50px;
  border-radius: 50%;
  cursor: pointer;
  display: flex;
  align-items: center;
  justify-content: center;
  box-shadow: 0 4px 10px rgba(0, 0, 0, 0.3);
  transition: var(--transition);
}

.toggle-btn:hover {
  transform: scale(1.1);
  box-shadow: 0 6px 15px rgba(0, 0, 0, 0.4);
}

/* Scroll Indicator */
.scroll-indicator {
  position: fixed;
  top: 0;
  left: 0;
  height: 5px;
  background: linear-gradient(to right, var(--primary-color), var(--accent-color));
  z-index: 1000;
  transition: width 0.3s ease;
}