:root {
  --primary-dark: #0f2027;
  --primary-mid: #203a43;
  --primary-light: #2c5364;
  --accent-blue: #00c6ff;
  --accent-teal: #7df9ff;
  --neutral-light: #ffffff;
  --neutral-mid: #cccccc;
  --neutral-dark: #1e2a38;
}

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

body {
  background: linear-gradient(135deg, var(--primary-dark), var(--primary-mid), var(--primary-light));
  color: var(--neutral-light);
  font-family: 'Roboto', sans-serif;
  line-height: 1.6;
  overflow-x: hidden;
}

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

.notice {
  background: rgba(255,255,255,0.1);
  padding: 15px;
  border-radius: 8px;
  margin: 20px 0;
  text-align: center;
  border-left: 4px solid var(--accent-blue);
}

article {
  background: rgba(30,42,56,0.7);
  border-radius: 12px;
  padding: 40px;
  margin: 40px 0;
  box-shadow: 0 10px 30px rgba(0,0,0,0.3);
  backdrop-filter: blur(10px);
}

h1, h2, h3, h4 {
  font-family: 'Montserrat', sans-serif;
  margin: 25px 0 15px;
  color: var(--accent-teal);
}

h2 {
  font-size: 2.2em;
  position: relative;
  padding-bottom: 10px;
}

h2::after {
  content: '';
  position: absolute;
  bottom: 0;
  left: 0;
  width: 80px;
  height: 3px;
  background: linear-gradient(90deg, var(--accent-blue), var(--accent-teal));
}

h3 {
  font-size: 1.8em;
  color: var(--accent-blue);
}

p {
  margin-bottom: 20px;
  font-size: 17px;
}

.img-grid {
  display: grid;
  grid-template-columns: repeat(auto-fill, minmax(300px, 1fr));
  gap: 20px;
  margin: 30px 0;
}

.img-card {
  position: relative;
  border-radius: 12px;
  overflow: hidden;
  box-shadow: 0 8px 20px rgba(0,0,0,0.2);
  transition: transform 0.3s ease, box-shadow 0.3s ease;
}

.img-card:hover {
  transform: translateY(-5px);
  box-shadow: 0 12px 25px rgba(0,198,255,0.3);
}

.img-card img {
  width: 100%;
  height: 100%;
  object-fit: cover;
  transition: transform 0.5s ease;
}

.img-card:hover img {
  transform: scale(1.05);
}

pre {
  background: rgba(15,32,39,0.8);
  border-radius: 8px;
  padding: 20px;
  margin: 25px 0;
  overflow: auto;
  border-left: 4px solid var(--accent-blue);
  font-family: 'Courier New', monospace;
  font-size: 15px;
  line-height: 1.5;
}

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

.nav-tabs {
  display: flex;
  margin: 30px 0;
  border-bottom: 1px solid rgba(255,255,255,0.1);
}

.nav-tab {
  padding: 12px 25px;
  cursor: pointer;
  position: relative;
  color: var(--neutral-mid);
  font-weight: 600;
}

.nav-tab::after {
  content: '';
  position: absolute;
  bottom: -1px;
  left: 0;
  width: 0;
  height: 3px;
  background: var(--accent-blue);
  transition: width 0.3s ease;
}

.nav-tab.active {
  color: var(--neutral-light);
}

.nav-tab.active::after {
  width: 100%;
}

.tab-content {
  display: none;
  animation: fadeIn 0.5s ease;
}

.tab-content.active {
  display: block;
}

@keyframes fadeIn {
  from { opacity: 0; }
  to { opacity: 1; }
}

.button {
  display: inline-block;
  background: linear-gradient(90deg, var(--accent-blue), var(--accent-teal));
  color: var(--primary-dark);
  padding: 12px 30px;
  border-radius: 30px;
  text-decoration: none;
  font-weight: 600;
  margin: 10px 0;
  transition: all 0.3s ease;
  box-shadow: 0 4px 15px rgba(0,198,255,0.3);
}

.button:hover {
  transform: translateY(-3px);
  box-shadow: 0 8px 25px rgba(0,198,255,0.5);
}

@media (max-width: 768px) {
  article {
    padding: 25px;
  }
  
  h2 {
    font-size: 1.8em;
  }
  
  h3 {
    font-size: 1.5em;
  }
  
  .img-grid {
    grid-template-columns: 1fr;
  }
}