:root {
  --primary: #0d1b2a;
  --secondary: #1b263b;
  --accent: #ff8c00;
  --text: #e0e1dd;
  --highlight: #415a77;
  --card-bg: rgba(255, 255, 255, 0.1);
}

@font-face {
  font-family: 'Roboto';
  src: url('https://fonts.googleapis.com/css2?family=Roboto:wght@300;400;500;700&display=swap');
}

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

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

.header {
  position: fixed;
  top: 0;
  left: 0;
  width: 100%;
  background: rgba(13, 27, 42, 0.95);
  padding: 1rem 2rem;
  display: flex;
  justify-content: space-between;
  align-items: center;
  z-index: 1000;
  box-shadow: 0 4px 30px rgba(0, 0, 0, 0.3);
  backdrop-filter: blur(10px);
}

.logo {
  font-size: 1.5rem;
  font-weight: 700;
  background: linear-gradient(to right, var(--accent), #ffd700);
  -webkit-background-clip: text;
  background-clip: text;
  color: transparent;
  text-shadow: 0 0 10px rgba(255, 140, 0, 0.3);
}

.nav-links {
  display: flex;
  gap: 2rem;
}

.nav-links a {
  color: var(--text);
  text-decoration: none;
  font-weight: 500;
  position: relative;
  padding: 0.5rem 0;
  transition: all 0.3s ease;
}

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

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

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

.banner {
  height: 400px;
  background: url('https://images.gptkong.com/demo/sample1.png') center/cover no-repeat;
  position: relative;
  margin-bottom: 3rem;
  border-radius: 0 0 20px 20px;
  overflow: hidden;
  box-shadow: 0 10px 30px rgba(0, 0, 0, 0.5);
}

.banner::before {
  content: '';
  position: absolute;
  top: 0;
  left: 0;
  width: 100%;
  height: 100%;
  background: linear-gradient(to right, rgba(13, 27, 42, 0.8), rgba(65, 90, 119, 0.6));
}

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

.banner h1 {
  font-size: 3rem;
  margin-bottom: 1rem;
  background: linear-gradient(to right, #ffffff, #e0e1dd);
  -webkit-background-clip: text;
  background-clip: text;
  color: transparent;
  text-shadow: 0 0 20px rgba(255, 255, 255, 0.2);
}

.banner p {
  font-size: 1.2rem;
  max-width: 700px;
  margin: 0 auto 2rem;
}

.notice {
  background: rgba(255, 140, 0, 0.2);
  border-left: 4px solid var(--accent);
  padding: 1rem;
  margin: 2rem 0;
  border-radius: 0 8px 8px 0;
  font-size: 0.9rem;
}

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

.main-content {
  display: grid;
  grid-template-columns: 1fr 300px;
  gap: 2rem;
  margin-bottom: 3rem;
}

.article {
  background: rgba(27, 38, 59, 0.7);
  padding: 2rem;
  border-radius: 15px;
  box-shadow: 0 10px 20px rgba(0, 0, 0, 0.2);
  backdrop-filter: blur(10px);
  border: 1px solid rgba(255, 255, 255, 0.1);
}

.article h2 {
  font-size: 2rem;
  margin-bottom: 1.5rem;
  color: #ffffff;
  position: relative;
  padding-bottom: 0.5rem;
}

.article h2::after {
  content: '';
  position: absolute;
  bottom: 0;
  left: 0;
  width: 100px;
  height: 3px;
  background: var(--accent);
  border-radius: 3px;
}

.article h3 {
  font-size: 1.5rem;
  margin: 2rem 0 1rem;
  color: #ffffff;
}

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

.article strong {
  color: var(--accent);
}

.sidebar {
  position: sticky;
  top: 100px;
  height: fit-content;
}

.side-card {
  background: rgba(27, 38, 59, 0.7);
  padding: 1.5rem;
  border-radius: 15px;
  margin-bottom: 2rem;
  box-shadow: 0 10px 20px rgba(0, 0, 0, 0.2);
  backdrop-filter: blur(10px);
  border: 1px solid rgba(255, 255, 255, 0.1);
}

.side-card h3 {
  font-size: 1.2rem;
  margin-bottom: 1rem;
  color: var(--accent);
}

.gallery {
  display: grid;
  grid-template-columns: repeat(2, 1fr);
  gap: 1rem;
}

.gallery img {
  width: 100%;
  height: auto;
  border-radius: 10px;
  transition: transform 0.3s ease, box-shadow 0.3s ease;
  box-shadow: 0 5px 15px rgba(0, 0, 0, 0.2);
}

.gallery img:hover {
  transform: scale(1.05);
  box-shadow: 0 10px 25px rgba(0, 0, 0, 0.3);
}

pre {
  background: rgba(13, 27, 42, 0.8);
  padding: 1.5rem;
  border-radius: 10px;
  overflow-x: auto;
  margin: 1.5rem 0;
  border-left: 4px solid var(--accent);
  font-family: 'Courier New', monospace;
  font-size: 0.9rem;
  line-height: 1.5;
  position: relative;
}

pre::before {
  content: 'CSS';
  position: absolute;
  top: 0;
  right: 0;
  background: var(--accent);
  color: white;
  padding: 0.2rem 0.5rem;
  font-size: 0.8rem;
  border-radius: 0 0 0 5px;
}

code {
  font-family: 'Courier New', monospace;
  background: rgba(255, 140, 0, 0.1);
  padding: 0.2rem 0.4rem;
  border-radius: 3px;
  font-size: 0.9rem;
}

.footer {
  background: rgba(13, 27, 42, 0.9);
  padding: 3rem 0;
  text-align: center;
  margin-top: 3rem;
  border-top: 1px solid rgba(255, 255, 255, 0.1);
}

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

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

.social-links a {
  color: var(--text);
  font-size: 1.5rem;
  transition: color 0.3s ease, transform 0.3s ease;
}

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

@media (max-width: 992px) {
  .main-content {
    grid-template-columns: 1fr;
  }
  
  .sidebar {
    position: static;
    display: grid;
    grid-template-columns: repeat(2, 1fr);
    gap: 2rem;
  }
  
  .banner h1 {
    font-size: 2.5rem;
  }
}

@media (max-width: 768px) {
  .nav-links {
    display: none;
  }
  
  .banner {
    height: 300px;
  }
  
  .banner h1 {
    font-size: 2rem;
  }
  
  .banner p {
    font-size: 1rem;
  }
  
  .article h2 {
    font-size: 1.8rem;
  }
  
  .sidebar {
    grid-template-columns: 1fr;
  }
}

@media (max-width: 576px) {
  .container {
    padding: 0 1rem;
  }
  
  .article {
    padding: 1.5rem;
  }
  
  .banner {
    height: 250px;
  }
  
  .banner h1 {
    font-size: 1.8rem;
  }
}

@keyframes float {
  0%, 100% {
    transform: translateY(0);
  }
  50% {
    transform: translateY(-10px);
  }
}

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

.decorative-element {
  position: absolute;
  width: 100px;
  height: 100px;
  background: rgba(255, 140, 0, 0.1);
  border-radius: 50%;
  filter: blur(30px);
  z-index: -1;
}

.decorative-element:nth-child(1) {
  top: 20%;
  left: 10%;
}

.decorative-element:nth-child(2) {
  bottom: 15%;
  right: 10%;
}

.tooltip {
  position: relative;
  display: inline-block;
  border-bottom: 1px dotted var(--accent);
  cursor: help;
}

.tooltip .tooltiptext {
  visibility: hidden;
  width: 200px;
  background-color: var(--secondary);
  color: #fff;
  text-align: center;
  border-radius: 6px;
  padding: 5px;
  position: absolute;
  z-index: 1;
  bottom: 125%;
  left: 50%;
  margin-left: -100px;
  opacity: 0;
  transition: opacity 0.3s;
}

.tooltip:hover .tooltiptext {
  visibility: visible;
  opacity: 1;
}