:root {
  --primary-green: #8DC63F;
  --primary-blue: #2E4053;
  --background-white: #FFFFFF;
  --secondary-gray: #F5F5F5;
  --accent-orange: #FFA726;
  --text-dark: #333333;
  --text-light: #777777;
}

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

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

.header {
  background: linear-gradient(135deg, var(--primary-blue), var(--primary-green));
  color: var(--background-white);
  padding: 80px 20px;
  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: 0.1;
  z-index: 0;
}

.header-content {
  position: relative;
  z-index: 1;
  max-width: 1200px;
  margin: 0 auto;
}

.header h1 {
  font-size: 2.8rem;
  margin-bottom: 20px;
  text-shadow: 0 2px 4px rgba(0,0,0,0.2);
}

.header p {
  font-size: 1.2rem;
  max-width: 800px;
  margin: 0 auto 30px;
}

.note-banner {
  background: rgba(255,255,255,0.2);
  padding: 15px;
  border-radius: 8px;
  display: inline-block;
  margin-top: 30px;
  backdrop-filter: blur(5px);
}

.container {
  max-width: 1200px;
  margin: 0 auto;
  padding: 40px 20px;
}

.grid-layout {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(500px, 1fr));
  gap: 30px;
  margin: 40px 0;
}

.card {
  background-color: var(--background-white);
  border-radius: 12px;
  box-shadow: 0 10px 30px rgba(0, 0, 0, 0.08);
  overflow: hidden;
  transition: transform 0.3s ease, box-shadow 0.3s ease;
  position: relative;
}

.card:hover {
  transform: translateY(-10px);
  box-shadow: 0 15px 40px rgba(0, 0, 0, 0.15);
}

.card-image {
  height: 250px;
  background-size: cover;
  background-position: center;
}

.card-content {
  padding: 30px;
}

h2, h3, h4 {
  color: var(--primary-blue);
  margin-bottom: 20px;
  line-height: 1.3;
}

h2 {
  font-size: 1.9rem;
  position: relative;
  padding-bottom: 10px;
}

h2::after {
  content: "";
  position: absolute;
  bottom: 0;
  left: 0;
  width: 60px;
  height: 3px;
  background: linear-gradient(to right, var(--primary-green), var(--primary-blue));
}

h3 {
  font-size: 1.6rem;
  margin-top: 30px;
}

p {
  margin-bottom: 20px;
  font-size: 1.1rem;
  color: var(--text-dark);
}

pre {
  background-color: #f8f8f8;
  border-radius: 8px;
  padding: 20px;
  overflow-x: auto;
  margin: 25px 0;
  box-shadow: inset 0 0 10px rgba(0,0,0,0.05);
  border-left: 4px solid var(--primary-green);
}

code {
  font-family: 'Courier New', monospace;
  font-size: 0.9rem;
  color: #333;
}

.parallax-section {
  height: 500px;
  background-attachment: fixed;
  background-position: center;
  background-repeat: no-repeat;
  background-size: cover;
  position: relative;
  margin: 60px 0;
}

.parallax-overlay {
  position: absolute;
  top: 0;
  left: 0;
  width: 100%;
  height: 100%;
  background: rgba(0,0,0,0.4);
  display: flex;
  align-items: center;
  justify-content: center;
  color: white;
  text-align: center;
  padding: 0 20px;
}

.button {
  display: inline-block;
  background-color: var(--accent-orange);
  color: var(--background-white);
  padding: 12px 24px;
  border: none;
  border-radius: 6px;
  cursor: pointer;
  transition: all 0.3s ease;
  font-weight: 500;
  text-decoration: none;
  margin: 10px 0;
}

.button:hover {
  background-color: #f57c00;
  transform: translateY(-2px);
  box-shadow: 0 5px 15px rgba(255,167,38,0.4);
}

.image-gallery {
  display: grid;
  grid-template-columns: repeat(auto-fill, minmax(300px, 1fr));
  gap: 20px;
  margin: 40px 0;
}

.gallery-image {
  border-radius: 8px;
  overflow: hidden;
  box-shadow: 0 5px 15px rgba(0,0,0,0.1);
  transition: all 0.3s ease;
}

.gallery-image:hover {
  transform: scale(1.03);
  box-shadow: 0 8px 25px rgba(0,0,0,0.15);
}

.gallery-image img {
  width: 100%;
  height: auto;
  display: block;
  transition: transform 0.5s ease;
}

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

.nav-tabs {
  display: flex;
  margin-bottom: 30px;
  border-bottom: 1px solid #eee;
}

.nav-tab {
  padding: 10px 20px;
  cursor: pointer;
  position: relative;
  color: var(--text-light);
  font-weight: 500;
}

.nav-tab.active {
  color: var(--primary-blue);
}

.nav-tab.active::after {
  content: "";
  position: absolute;
  bottom: -1px;
  left: 0;
  width: 100%;
  height: 3px;
  background: linear-gradient(to right, var(--primary-green), var(--primary-blue));
}

.footer {
  background-color: var(--primary-blue);
  color: var(--background-white);
  padding: 40px 20px;
  text-align: center;
  margin-top: 60px;
}

@media (max-width: 768px) {
  .grid-layout {
    grid-template-columns: 1fr;
  }
  
  .header h1 {
    font-size: 2.2rem;
  }
  
  .header p {
    font-size: 1rem;
  }
  
  h2 {
    font-size: 1.6rem;
  }
  
  h3 {
    font-size: 1.4rem;
  }
}

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

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