:root {
  --primary-blue: #2D3A4B;
  --secondary-gray: #4A4A4A;
  --accent-yellow: #FFC107;
  --accent-orange: #FF5722;
  --background-light: #f8f9fa;
  --text-dark: #212529;
  --text-light: #f8f9fa;
  --border-radius: 12px;
  --box-shadow: 0 8px 24px rgba(0, 0, 0, 0.12);
  --transition: all 0.3s cubic-bezier(0.25, 0.8, 0.25, 1);
}

body {
  font-family: 'Roboto', 'Helvetica Neue', Arial, sans-serif;
  line-height: 1.6;
  color: var(--text-dark);
  background-color: var(--background-light);
  margin: 0;
  padding: 0;
  overflow-x: hidden;
}

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

.header {
  background: linear-gradient(135deg, var(--primary-blue), var(--accent-orange));
  color: white;
  padding: 2rem;
  border-radius: var(--border-radius);
  margin-bottom: 3rem;
  box-shadow: var(--box-shadow);
  position: relative;
  overflow: hidden;
}

.header::before {
  content: "";
  position: absolute;
  top: -50%;
  left: -50%;
  width: 200%;
  height: 200%;
  background: radial-gradient(circle, rgba(255,255,255,0.1) 0%, rgba(255,255,255,0) 70%);
  animation: pulse 15s infinite alternate;
}

@keyframes pulse {
  0% { transform: translate(0, 0); }
  100% { transform: translate(50px, 50px); }
}

h1, h2, h3, h4 {
  font-weight: 600;
  margin-top: 2rem;
  margin-bottom: 1rem;
  line-height: 1.3;
}

h1 {
  font-size: 2.5rem;
  color: white;
}

h2 {
  font-size: 2rem;
  color: var(--primary-blue);
  border-bottom: 2px solid var(--accent-yellow);
  padding-bottom: 0.5rem;
  display: inline-block;
}

h3 {
  font-size: 1.5rem;
  color: var(--secondary-gray);
}

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

article {
  background: white;
  border-radius: var(--border-radius);
  padding: 3rem;
  box-shadow: var(--box-shadow);
  margin-bottom: 3rem;
}

.code-block {
  background: #2D3A4B;
  color: #f8f9fa;
  padding: 1.5rem;
  border-radius: var(--border-radius);
  margin: 2rem 0;
  overflow-x: auto;
  font-family: 'Courier New', monospace;
  position: relative;
}

.code-block::before {
  content: "CSS";
  position: absolute;
  top: 0;
  left: 0;
  background: var(--accent-orange);
  color: white;
  padding: 0.25rem 1rem;
  border-radius: var(--border-radius) 0 var(--border-radius) 0;
  font-size: 0.8rem;
}

.grid-container {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(300px, 1fr));
  gap: 2rem;
  margin: 3rem 0;
}

.card {
  background: white;
  border-radius: var(--border-radius);
  padding: 2rem;
  box-shadow: var(--box-shadow);
  transition: var(--transition);
}

.card:hover {
  transform: translateY(-5px);
  box-shadow: 0 12px 28px rgba(0, 0, 0, 0.15);
}

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

.decorative-img {
  width: 150px;
  height: 150px;
  object-fit: cover;
  border-radius: var(--border-radius);
  box-shadow: 0 4px 8px rgba(0, 0, 0, 0.1);
  transition: var(--transition);
}

.decorative-img:hover {
  transform: scale(1.05);
  box-shadow: 0 8px 16px rgba(0, 0, 0, 0.2);
}

.nav-links {
  display: flex;
  flex-wrap: wrap;
  gap: 1rem;
  margin: 2rem 0;
}

.nav-link {
  padding: 0.75rem 1.5rem;
  background: var(--primary-blue);
  color: white;
  border-radius: 50px;
  text-decoration: none;
  transition: var(--transition);
  font-weight: 500;
}

.nav-link:hover {
  background: var(--accent-orange);
  transform: translateY(-2px);
}

.notice {
  background: var(--accent-yellow);
  color: var(--text-dark);
  padding: 1rem;
  border-radius: var(--border-radius);
  margin: 2rem 0;
  text-align: center;
  font-weight: 500;
}

@media (max-width: 768px) {
  .container {
    padding: 1rem;
  }
  
  article {
    padding: 2rem 1rem;
  }
  
  h1 {
    font-size: 2rem;
  }
  
  h2 {
    font-size: 1.5rem;
  }
}

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

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