:root {
  --primary: #0D47A1;
  --secondary: #388E3C;
  --accent: #FF9800;
  --light: #42A5F5;
  --dark: #0a2d5a;
  --text: #f5f5f5;
  --bg: linear-gradient(135deg, var(--primary), var(--light));
  --card-bg: rgba(255, 255, 255, 0.1);
  --shadow: 0 8px 32px rgba(0, 0, 0, 0.2);
}

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

body {
  background: var(--bg);
  color: var(--text);
  font-family: 'Roboto', sans-serif;
  line-height: 1.6;
  padding: 0;
  margin: 0;
  min-height: 100%;
  overflow-x: hidden;
}

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

.header {
  text-align: center;
  padding: 3rem 0;
  position: relative;
  overflow: hidden;
}

.header::before {
  content: "";
  position: absolute;
  top: 0;
  left: 0;
  width: 100%;
  height: 100%;
  background: radial-gradient(circle at 50% 50%, rgba(255,255,255,0.1) 0%, transparent 70%);
  z-index: -1;
}

h1, h2, h3, h4 {
  font-weight: 700;
  margin-bottom: 1.5rem;
  line-height: 1.3;
}

h1 {
  font-size: 2.8rem;
  background: linear-gradient(90deg, var(--text), var(--light));
  -webkit-background-clip: text;
  background-clip: text;
  color: transparent;
  text-shadow: 0 2px 4px rgba(0,0,0,0.2);
}

h2 {
  font-size: 2.2rem;
  color: var(--text);
  position: relative;
  padding-bottom: 1rem;
}

h2::after {
  content: "";
  position: absolute;
  bottom: 0;
  left: 0;
  width: 80px;
  height: 4px;
  background: linear-gradient(90deg, var(--secondary), var(--accent));
  border-radius: 2px;
}

h3 {
  font-size: 1.8rem;
  color: var(--light);
  margin-top: 2rem;
}

p {
  font-size: 1.1rem;
  margin-bottom: 1.5rem;
  color: rgba(255,255,255,0.9);
}

strong {
  color: var(--light);
}

em {
  font-style: italic;
  color: var(--accent);
}

a {
  color: var(--light);
  text-decoration: none;
  transition: all 0.3s ease;
}

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

.nav {
  position: fixed;
  top: 0;
  left: 0;
  width: 100%;
  background: rgba(13, 71, 161, 0.9);
  backdrop-filter: blur(10px);
  z-index: 1000;
  padding: 1rem 2rem;
  box-shadow: 0 2px 10px rgba(0,0,0,0.1);
}

.nav-list {
  display: flex;
  justify-content: center;
  list-style: none;
  gap: 2rem;
}

.nav-link {
  color: var(--text);
  font-weight: 500;
  padding: 0.5rem 1rem;
  border-radius: 4px;
  transition: all 0.3s ease;
}

.nav-link:hover {
  background: rgba(255,255,255,0.1);
  color: var(--accent);
}

.section {
  padding: 4rem 0;
  position: relative;
}

.section::before {
  content: "";
  position: absolute;
  top: 0;
  left: 0;
  width: 100%;
  height: 100%;
  background: url('https://images.gptkong.com/demo/sample1.png') no-repeat;
  background-size: 30%;
  background-position: right bottom;
  opacity: 0.1;
  z-index: -1;
}

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

.card:hover {
  transform: translateY(-5px);
  box-shadow: 0 12px 24px rgba(0,0,0,0.3);
}

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

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

.img-box {
  width: 150px;
  height: 150px;
  border-radius: 12px;
  overflow: hidden;
  box-shadow: 0 4px 8px rgba(0,0,0,0.2);
  transition: all 0.3s ease;
}

.img-box:hover {
  transform: scale(1.05);
  box-shadow: 0 8px 16px rgba(0,0,0,0.3);
}

.img-box img {
  width: 100%;
  height: 100%;
  object-fit: cover;
}

pre {
  background: rgba(0,0,0,0.3);
  border-radius: 8px;
  padding: 1.5rem;
  overflow-x: auto;
  margin: 2rem 0;
  border-left: 4px solid var(--accent);
  font-family: 'Courier New', monospace;
  font-size: 0.9rem;
  line-height: 1.5;
}

code {
  background: rgba(0,0,0,0.2);
  padding: 0.2rem 0.4rem;
  border-radius: 4px;
  font-family: 'Courier New', monospace;
  font-size: 0.9rem;
}

table {
  width: 100%;
  border-collapse: collapse;
  margin: 2rem 0;
  background: rgba(0,0,0,0.2);
  border-radius: 8px;
  overflow: hidden;
}

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

th {
  background: rgba(0,0,0,0.3);
  color: var(--light);
  font-weight: 500;
}

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

.notice {
  position: fixed;
  bottom: 20px;
  right: 20px;
  background: var(--secondary);
  color: white;
  padding: 1rem;
  border-radius: 8px;
  box-shadow: 0 4px 12px rgba(0,0,0,0.2);
  z-index: 1000;
  animation: slideIn 0.5s ease-out;
}

@keyframes slideIn {
  from {
    transform: translateX(100%);
    opacity: 0;
  }
  to {
    transform: translateX(0);
    opacity: 1;
  }
}

.button {
  display: inline-block;
  background: var(--secondary);
  color: white;
  padding: 0.8rem 1.5rem;
  border-radius: 50px;
  font-weight: 500;
  transition: all 0.3s ease;
  box-shadow: 0 4px 6px rgba(0,0,0,0.1);
  border: none;
  cursor: pointer;
  margin: 0.5rem 0;
}

.button:hover {
  background: var(--accent);
  transform: translateY(-2px);
  box-shadow: 0 6px 12px rgba(0,0,0,0.2);
}

.fade-in {
  opacity: 0;
  animation: fadeIn 1s forwards;
}

@keyframes fadeIn {
  to {
    opacity: 1;
  }
}

.chart-bar {
  width: 100px;
  height: 0;
  background: linear-gradient(to top, var(--light), var(--primary));
  animation: grow 2s forwards;
  border-radius: 4px 4px 0 0;
  margin: 0 auto;
}

@keyframes grow {
  to {
    height: 200px;
  }
}

@media (max-width: 768px) {
  .nav-list {
    gap: 1rem;
  }
  
  h1 {
    font-size: 2.2rem;
  }
  
  h2 {
    font-size: 1.8rem;
  }
  
  h3 {
    font-size: 1.5rem;
  }
  
  .section {
    padding: 3rem 0;
  }
}

@media (max-width: 480px) {
  .nav-list {
    flex-direction: column;
    align-items: center;
    gap: 0.5rem;
  }
  
  .nav {
    padding: 0.5rem;
  }
  
  h1 {
    font-size: 1.8rem;
  }
  
  .img-box {
    width: 120px;
    height: 120px;
  }
}