:root {
  --body-background: #fafafa;
  --body-color: #333;
  --heading-color: #1a1a1a;
  --action-color: #2563eb;
  --action-hover: #1d4ed8;
  --card-background: #ffffff;
  --border-color: #e5e7eb;
  --text-muted: #6b7280;
  --nav-background: #ffffff;
  --shadow: 0 4px 6px -1px rgba(0, 0, 0, 0.1), 0 2px 4px -1px rgba(0, 0, 0, 0.06);
}

* {
  box-sizing: border-box;
}

body {
  background: var(--body-background);
  color: var(--body-color);
  font-family: -apple-system, BlinkMacSystemFont, "Segoe UI", Roboto, "Helvetica Neue", Arial, sans-serif;
  margin: 0;
  font-size: 16px;
  line-height: 1.6;
}

a {
  color: var(--action-color);
  text-decoration: none;
  transition: color 0.2s ease;
}

a:hover {
  color: var(--action-hover);
  text-decoration: underline;
}

h1, h2, h3, h4, h5, h6 {
  color: var(--heading-color);
  line-height: 1.3;
  margin-top: 0;
  margin-bottom: 1rem;
}

h1 {
  font-size: 2.5rem;
  font-weight: 700;
  margin-bottom: 1.5rem;
}

h2 {
  font-size: 1.875rem;
  font-weight: 600;
}

h3 {
  font-size: 1.5rem;
  font-weight: 600;
}

p {
  margin-bottom: 1.5rem;
}

.container {
  max-width: 1024px;
  margin: 0 auto;
  padding: 0 1rem;
}

body > header {
  background: var(--nav-background);
  border-bottom: 1px solid var(--border-color);
  position: sticky;
  top: 0;
  z-index: 100;
  box-shadow: var(--shadow);
}

body > header .container {
  display: flex;
  justify-content: space-between;
  align-items: center;
  padding: 1rem;
}

body > header h1 {
  margin: 0;
  font-size: 1.5rem;
  font-weight: 700;
}

header nav ul {
  margin: 0;
  padding: 0;
  list-style-type: none;
  display: flex;
  gap: 2rem;
}

header nav a {
  font-weight: 500;
  padding: 0.5rem 0;
  border-bottom: 2px solid transparent;
  transition: border-color 0.2s ease;
}

header nav a:hover {
  border-bottom-color: var(--action-color);
  text-decoration: none;
}

main {
  padding: 3rem 0;
  min-height: calc(100vh - 200px);
}

.hero {
  text-align: center;
  padding: 4rem 0;
  margin-bottom: 3rem;
}

.hero h1 {
  font-size: 3.5rem;
  margin-bottom: 1rem;
  background: linear-gradient(135deg, var(--heading-color), var(--action-color));
  -webkit-background-clip: text;
  -webkit-text-fill-color: transparent;
  background-clip: text;
}

.hero p {
  font-size: 1.25rem;
  color: var(--text-muted);
  max-width: 600px;
  margin: 0 auto;
}

.card {
  background: var(--card-background);
  border: 1px solid var(--border-color);
  border-radius: 8px;
  padding: 2rem;
  margin-bottom: 2rem;
  box-shadow: var(--shadow);
}

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

.btn {
  display: inline-block;
  background: var(--action-color);
  color: white;
  padding: 0.75rem 1.5rem;
  border-radius: 6px;
  font-weight: 500;
  text-decoration: none;
  transition: background-color 0.2s ease;
}

.btn:hover {
  background: var(--action-hover);
  color: white;
  text-decoration: none;
}

.text-center {
  text-align: center;
}

.text-muted {
  color: var(--text-muted);
}

footer {
  background: var(--nav-background);
  border-top: 1px solid var(--border-color);
  padding: 2rem 0;
  text-align: center;
  color: var(--text-muted);
}

@media (max-width: 768px) {
  body > header .container {
    flex-direction: column;
    gap: 1rem;
  }
  
  header nav ul {
    gap: 1rem;
  }
  
  .hero h1 {
    font-size: 2.5rem;
  }
  
  .hero p {
    font-size: 1.1rem;
  }
  
  main {
    padding: 2rem 0;
  }
  
  .card {
    padding: 1.5rem;
  }
}

header nav a[aria-current="page"] {
  border-bottom-color: var(--action-color);
}

.post-header {
  margin-bottom: 2.5rem;
  padding-bottom: 1.5rem;
  border-bottom: 1px solid var(--border-color);
}

.post-header h1 {
  margin-bottom: 0.5rem;
}

.post-header p {
  margin-bottom: 0;
}

.post code {
  font-size: 0.9em;
}

.post :not(pre) > code {
  background: var(--border-color);
  border-radius: 3px;
  padding: 0.15em 0.35em;
}