@import url('https://fonts.googleapis.com/css2?family=DM+Sans:wght@400;500;700&family=Inter:wght@400;500;600;700;800&family=JetBrains+Mono:wght@400;500&display=swap');

:root {
  --stone-50: #fafaf9;
  --stone-100: #f5f5f4;
  --stone-200: #e7e5e4;
  --stone-300: #d6d3d1;
  --stone-400: #a8a29e;
  --stone-500: #78716c;
  --stone-600: #57534e;
  --stone-700: #44403c;
  --stone-800: #292524;
  --stone-900: #1c1917;
  --accent: #2563eb;
  --accent-light: #dbeafe;
}

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

body {
  font-family: 'DM Sans', -apple-system, BlinkMacSystemFont, sans-serif;
  background: var(--stone-50);
  color: var(--stone-800);
  line-height: 1.7;
}

header {
  background: rgba(250, 250, 249, 0.9);
  backdrop-filter: blur(20px);
  border-bottom: 1px solid var(--stone-200);
  position: sticky;
  top: 0;
  z-index: 100;
}

.header-inner {
  max-width: 1200px;
  margin: 0 auto;
  padding: 0 2rem;
  height: 64px;
  display: flex;
  align-items: center;
}

.logo-text {
  font-family: 'Inter', sans-serif;
  font-weight: 700;
  font-size: 1rem;
  color: var(--stone-900);
  text-decoration: none;
  letter-spacing: -0.02em;
}

.layout {
  max-width: 1200px;
  margin: 0 auto;
  display: flex;
  min-height: calc(100vh - 64px - 60px);
}

.sidebar {
  width: 240px;
  flex-shrink: 0;
  padding: 2rem 1.5rem;
  border-right: 1px solid var(--stone-100);
}

.nav-list { list-style: none; }
.nav-list li { margin-bottom: 0.25rem; }

.nav-list a {
  display: block;
  padding: 0.4rem 0.75rem;
  color: var(--stone-600);
  text-decoration: none;
  font-size: 0.9rem;
  border-radius: 6px;
  transition: background 0.15s, color 0.15s;
}

.nav-list a:hover {
  background: var(--stone-100);
  color: var(--stone-900);
}

.nav-list a.active {
  color: var(--accent);
  font-weight: 600;
  background: var(--accent-light);
}

.content {
  flex: 1;
  padding: 2rem 3rem;
  max-width: 800px;
}

h1, h2, h3, h4, h5, h6 {
  font-family: 'Inter', sans-serif;
  color: var(--stone-900);
}

h1 {
  font-weight: 800;
  font-size: 2rem;
  letter-spacing: -0.03em;
  margin-bottom: 1.5rem;
}

h2 {
  font-weight: 700;
  font-size: 1.5rem;
  letter-spacing: -0.02em;
  border-bottom: 1px solid var(--stone-200);
  padding-bottom: 0.5rem;
  margin-top: 2.5rem;
  margin-bottom: 1rem;
}

h3 {
  font-weight: 600;
  font-size: 1.2rem;
  margin-top: 2rem;
  margin-bottom: 0.75rem;
}

p { color: var(--stone-600); margin-bottom: 1rem; }

a { color: var(--accent); text-decoration: underline; text-underline-offset: 2px; }
a:hover { color: var(--stone-900); }

ul, ol { padding-left: 1.5rem; margin-bottom: 1rem; color: var(--stone-600); }
li { margin-bottom: 0.35rem; }

code {
  font-family: 'JetBrains Mono', monospace;
  background: var(--stone-100);
  color: var(--stone-800);
  padding: 0.2em 0.4em;
  border-radius: 4px;
  font-size: 0.875em;
}

pre {
  background: var(--stone-900);
  border-radius: 12px;
  padding: 1.25rem;
  margin-bottom: 1.5rem;
  overflow-x: auto;
}

pre code { background: none; color: var(--stone-100); padding: 0; }

blockquote {
  border-left: 3px solid var(--accent);
  background: var(--accent-light);
  padding: 1rem 1.25rem;
  border-radius: 0 8px 8px 0;
  color: var(--stone-700);
  margin-bottom: 1rem;
}

table {
  border-collapse: collapse;
  border: 1px solid var(--stone-200);
  border-radius: 12px;
  overflow: hidden;
  width: 100%;
  margin-bottom: 1.5rem;
}

th {
  background: var(--stone-100);
  font-weight: 600;
  color: var(--stone-700);
  text-align: left;
}

th, td { padding: 0.6rem 1rem; border: 1px solid var(--stone-200); }
img { max-width: 100%; border-radius: 8px; }

footer {
  border-top: 1px solid var(--stone-200);
  padding: 1.25rem 2rem;
  text-align: center;
  color: var(--stone-400);
  font-size: 0.85rem;
}

@media (max-width: 768px) {
  .sidebar { display: none; }
  .content { padding: 1.5rem 1rem; }
}

::selection { background: var(--accent-light); }