:root {
  /* Dark mode is the default */
  --color-bg: #0a0a0a;
  --color-bg-subtle: #141414;
  --color-surface: #171717;
  --color-border: #262626;
  --color-border-strong: #404040;
  --color-text: #f5f5f5;
  --color-text-secondary: #a3a3a3;
  --color-text-muted: #737373;
  --color-accent: #e5e5e5;
  --color-accent-hover: #ffffff;
  --color-accent-soft: #262626;
  --color-pastel-blue: #1a2332;
  --color-pastel-blue-border: #2a3a4f;
  --color-pastel-green: #1a2f23;
  --color-pastel-green-border: #2a4f3a;
  --color-pastel-amber: #2f261a;
  --color-pastel-amber-border: #4f3f2a;
  --color-pastel-gray: #1a1a1a;
  --color-pastel-gray-border: #333333;
  --color-code-bg: #111111;
  --color-code-text: #e5e5e5;

  --font-sans: -apple-system, BlinkMacSystemFont, "Segoe UI", Roboto, "Helvetica Neue", Arial, sans-serif;
  --font-mono: ui-monospace, SFMono-Regular, "SF Mono", Menlo, Consolas, monospace;

  --space-1: 0.25rem;
  --space-2: 0.5rem;
  --space-3: 0.75rem;
  --space-4: 1rem;
  --space-5: 1.25rem;
  --space-6: 1.5rem;
  --space-8: 2rem;
  --space-10: 2.5rem;
  --space-12: 3rem;
  --space-16: 4rem;

  --radius-sm: 4px;
  --radius-md: 6px;
  --radius-lg: 8px;

  --sidebar-width: 280px;
  --toc-width: 240px;
  --max-content-width: 768px;
}

[data-theme="light"] {
  --color-bg: #ffffff;
  --color-bg-subtle: #fafafa;
  --color-surface: #ffffff;
  --color-border: #e5e7eb;
  --color-border-strong: #d4d4d4;
  --color-text: #171717;
  --color-text-secondary: #525252;
  --color-text-muted: #737373;
  --color-accent: #262626;
  --color-accent-hover: #000000;
  --color-accent-soft: #f5f5f5;
  --color-pastel-blue: #eff6ff;
  --color-pastel-blue-border: #dbeafe;
  --color-pastel-green: #f0fdf4;
  --color-pastel-green-border: #dcfce7;
  --color-pastel-amber: #fffbeb;
  --color-pastel-amber-border: #fef3c7;
  --color-pastel-gray: #f8fafc;
  --color-pastel-gray-border: #e2e8f0;
  --color-code-bg: #f8fafc;
  --color-code-text: #0f172a;
}

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

html {
  color-scheme: dark;
  scroll-behavior: smooth;
  scroll-padding-top: var(--space-8);
}

[data-theme="light"] html {
  color-scheme: light;
}

body {
  font-family: var(--font-sans);
  font-size: 16px;
  line-height: 1.65;
  color: var(--color-text);
  background: var(--color-bg);
  -webkit-font-smoothing: antialiased;
}

a {
  color: var(--color-accent);
  text-decoration: underline;
  text-underline-offset: 2px;
  text-decoration-thickness: 1px;
  transition: color 0.15s ease;
}

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

/* Layout */
.page {
  display: flex;
  min-height: 100vh;
}

/* Sidebar */
.sidebar {
  position: fixed;
  top: 0;
  left: 0;
  width: var(--sidebar-width);
  height: 100vh;
  border-right: 1px solid var(--color-border);
  background: var(--color-bg);
  display: flex;
  flex-direction: column;
  overflow-y: auto;
  z-index: 100;
}

.sidebar-header {
  display: flex;
  align-items: flex-start;
  justify-content: space-between;
  gap: var(--space-3);
  padding: var(--space-6) var(--space-6) var(--space-4);
  border-bottom: 1px solid var(--color-border);
}

.sidebar-brand {
  min-width: 0;
}

.site-title {
  font-size: 1.125rem;
  font-weight: 600;
  letter-spacing: -0.01em;
  color: var(--color-text);
  text-decoration: none;
}

.site-title:hover {
  color: var(--color-accent-hover);
}

.site-tagline {
  font-size: 0.8125rem;
  color: var(--color-text-muted);
  margin-top: var(--space-1);
}

.theme-toggle {
  background: var(--color-accent-soft);
  border: 1px solid var(--color-border);
  border-radius: var(--radius-md);
  color: var(--color-text-secondary);
  cursor: pointer;
  padding: var(--space-2);
  display: flex;
  align-items: center;
  justify-content: center;
  transition: background 0.15s ease, color 0.15s ease, border-color 0.15s ease;
  flex-shrink: 0;
}

.theme-toggle:hover {
  background: var(--color-bg-subtle);
  color: var(--color-text);
  border-color: var(--color-border-strong);
}

.theme-toggle svg {
  width: 18px;
  height: 18px;
}

.theme-toggle .icon-sun,
.theme-toggle .icon-moon {
  display: none;
}

[data-theme="light"] .theme-toggle .icon-moon,
html:not([data-theme="light"]) .theme-toggle .icon-sun {
  display: block;
}

.mobile-actions {
  display: flex;
  align-items: center;
  gap: var(--space-2);
}

.header-actions {
  display: flex;
  align-items: center;
  gap: var(--space-2);
  flex-shrink: 0;
}

.github-link {
  display: flex;
  align-items: center;
  justify-content: center;
  width: 34px;
  height: 34px;
  background: var(--color-accent-soft);
  border: 1px solid var(--color-border);
  border-radius: var(--radius-md);
  color: var(--color-text-secondary);
  text-decoration: none;
  transition: background 0.15s ease, color 0.15s ease, border-color 0.15s ease;
}

.github-link:hover {
  background: var(--color-bg-subtle);
  color: var(--color-text);
  border-color: var(--color-border-strong);
}

.github-link svg {
  width: 18px;
  height: 18px;
}

.sidebar-nav {
  padding: var(--space-4) var(--space-4) var(--space-6);
  flex: 1;
}

.nav-section {
  margin-bottom: var(--space-5);
}

.nav-section-title {
  font-size: 0.6875rem;
  font-weight: 600;
  text-transform: uppercase;
  letter-spacing: 0.06em;
  color: var(--color-text-muted);
  padding: var(--space-2) var(--space-4);
  margin-bottom: var(--space-1);
}

.nav-link {
  display: block;
  padding: var(--space-2) var(--space-4);
  font-size: 0.875rem;
  color: var(--color-text-secondary);
  text-decoration: none;
  border-radius: var(--radius-md);
  transition: background 0.15s ease, color 0.15s ease;
}

.nav-link:hover {
  background: var(--color-accent-soft);
  color: var(--color-text);
}

.nav-link.active {
  background: var(--color-accent-soft);
  color: var(--color-text);
  font-weight: 500;
}

.sidebar-footer {
  padding: var(--space-4) var(--space-6);
  border-top: 1px solid var(--color-border);
  font-size: 0.75rem;
  color: var(--color-text-muted);
}

/* Main content */
.main {
  margin-left: var(--sidebar-width);
  flex: 1;
  min-width: 0;
  display: flex;
  justify-content: center;
}

.content {
  width: 100%;
  max-width: var(--max-content-width);
  padding: var(--space-10) var(--space-8) var(--space-16);
}

/* Mobile header */
.mobile-header {
  display: none;
  position: fixed;
  top: 0;
  left: 0;
  right: 0;
  height: 56px;
  background: var(--color-bg);
  border-bottom: 1px solid var(--color-border);
  align-items: center;
  justify-content: space-between;
  padding: 0 var(--space-5);
  z-index: 200;
}

.menu-button {
  background: none;
  border: none;
  padding: var(--space-2);
  cursor: pointer;
  color: var(--color-text);
}

.menu-button svg {
  width: 24px;
  height: 24px;
}

/* Typography */
.content h1 {
  font-size: 2.25rem;
  font-weight: 600;
  letter-spacing: -0.02em;
  line-height: 1.2;
  margin-bottom: var(--space-4);
  color: var(--color-text);
}

.content h2 {
  font-size: 1.5rem;
  font-weight: 600;
  letter-spacing: -0.01em;
  line-height: 1.3;
  margin-top: var(--space-12);
  margin-bottom: var(--space-4);
  padding-bottom: var(--space-3);
  border-bottom: 1px solid var(--color-border);
  color: var(--color-text);
}

.content h3 {
  font-size: 1.125rem;
  font-weight: 600;
  line-height: 1.4;
  margin-top: var(--space-8);
  margin-bottom: var(--space-3);
  color: var(--color-text);
}

.content h4 {
  font-size: 1rem;
  font-weight: 600;
  margin-top: var(--space-6);
  margin-bottom: var(--space-2);
  color: var(--color-text);
}

.content p {
  margin-bottom: var(--space-4);
  color: var(--color-text-secondary);
}

.content p:first-of-type {
  color: var(--color-text);
  font-size: 1.125rem;
  line-height: 1.6;
}

.content ul,
.content ol {
  margin-bottom: var(--space-4);
  padding-left: var(--space-6);
  color: var(--color-text-secondary);
}

.content li {
  margin-bottom: var(--space-2);
}

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

.content strong {
  color: var(--color-text);
  font-weight: 600;
}

.content hr {
  border: none;
  border-top: 1px solid var(--color-border);
  margin: var(--space-10) 0;
}

/* Lead paragraph */
.lead {
  font-size: 1.25rem;
  line-height: 1.6;
  color: var(--color-text-secondary);
  margin-bottom: var(--space-8);
}

/* Tables */
.content table {
  width: 100%;
  border-collapse: collapse;
  margin: var(--space-5) 0 var(--space-6);
  font-size: 0.875rem;
}

.content th,
.content td {
  padding: var(--space-3) var(--space-4);
  text-align: left;
  border-bottom: 1px solid var(--color-border);
}

.content th {
  font-weight: 600;
  color: var(--color-text);
  background: var(--color-bg-subtle);
  border-top: 1px solid var(--color-border);
}

.content tr:last-child td {
  border-bottom: 1px solid var(--color-border-strong);
}

.content code {
  font-family: var(--font-mono);
  font-size: 0.85em;
  background: var(--color-code-bg);
  color: var(--color-code-text);
  padding: 0.15em 0.4em;
  border-radius: var(--radius-sm);
  border: 1px solid var(--color-border);
}

.content pre {
  background: var(--color-code-bg);
  border: 1px solid var(--color-border);
  border-radius: var(--radius-md);
  padding: var(--space-4);
  overflow-x: auto;
  margin: var(--space-4) 0 var(--space-6);
}

.content pre code {
  background: none;
  border: none;
  padding: 0;
  font-size: 0.8125rem;
  line-height: 1.6;
}

/* Callouts */
.callout {
  padding: var(--space-4) var(--space-5);
  border-radius: var(--radius-md);
  border: 1px solid var(--color-border);
  margin: var(--space-5) 0;
  font-size: 0.9375rem;
}

.callout p {
  margin-bottom: 0;
  color: var(--color-text-secondary);
}

.callout-note {
  background: var(--color-pastel-blue);
  border-color: var(--color-pastel-blue-border);
}

.callout-tip {
  background: var(--color-pastel-green);
  border-color: var(--color-pastel-green-border);
}

.callout-warning {
  background: var(--color-pastel-amber);
  border-color: var(--color-pastel-amber-border);
}

.callout-title {
  font-weight: 600;
  color: var(--color-text);
  margin-bottom: var(--space-1);
}

/* Steps */
.steps {
  counter-reset: step;
  list-style: none;
  padding-left: 0;
}

.steps > li {
  position: relative;
  padding-left: var(--space-10);
  margin-bottom: var(--space-6);
  min-height: 2rem;
}

.steps > li::before {
  counter-increment: step;
  content: counter(step);
  position: absolute;
  left: 0;
  top: 0;
  width: 28px;
  height: 28px;
  border-radius: 50%;
  background: var(--color-accent);
  color: var(--color-bg);
  font-size: 0.8125rem;
  font-weight: 600;
  display: flex;
  align-items: center;
  justify-content: center;
}

.steps h4 {
  margin-top: 0;
  margin-bottom: var(--space-2);
}

/* Architecture diagram */
.diagram {
  background: var(--color-bg);
  border: 1px solid var(--color-border);
  border-radius: var(--radius-lg);
  padding: var(--space-6);
  margin: var(--space-6) 0;
  overflow-x: auto;
}

.diagram .mermaid-source {
  display: none;
}

.diagram svg {
  display: block;
  margin: 0 auto;
  max-width: 100%;
  height: auto;
}

.diagram .node rect,
.diagram .node circle,
.diagram .node polygon {
  stroke-width: 1px;
}

.diagram .edgeLabel {
  background-color: var(--color-bg) !important;
}

/* Pipelines */
.pipeline {
  display: grid;
  gap: var(--space-3);
  margin: var(--space-5) 0;
}

.pipeline-step {
  display: flex;
  align-items: flex-start;
  gap: var(--space-4);
  padding: var(--space-4);
  background: var(--color-bg-subtle);
  border: 1px solid var(--color-border);
  border-radius: var(--radius-md);
}

.pipeline-number {
  flex-shrink: 0;
  width: 28px;
  height: 28px;
  border-radius: 50%;
  background: var(--color-accent);
  color: var(--color-bg);
  font-size: 0.8125rem;
  font-weight: 600;
  display: flex;
  align-items: center;
  justify-content: center;
}

.pipeline-content {
  flex: 1;
}

.pipeline-content strong {
  display: block;
  margin-bottom: var(--space-1);
}

/* Back to top */
.back-to-top {
  display: inline-flex;
  align-items: center;
  gap: var(--space-2);
  margin-top: var(--space-12);
  font-size: 0.875rem;
  color: var(--color-text-muted);
  text-decoration: none;
}

.back-to-top:hover {
  color: var(--color-text);
}

/* Responsive */
@media (max-width: 1100px) {
  .main {
    margin-left: 0;
    padding-top: 56px;
  }

  .mobile-header {
    display: flex;
  }

  .sidebar {
    transform: translateX(-100%);
    transition: transform 0.2s ease;
    width: 280px;
    box-shadow: 0 0 0 9999px rgba(0, 0, 0, 0);
  }

  .sidebar.open {
    transform: translateX(0);
    box-shadow: 0 0 0 9999px rgba(0, 0, 0, 0.2);
  }

  .content {
    padding: var(--space-8) var(--space-5) var(--space-12);
  }
}

@media (max-width: 640px) {
  .content h1 {
    font-size: 1.75rem;
  }

  .content h2 {
    font-size: 1.25rem;
  }

  .content {
    padding: var(--space-6) var(--space-4) var(--space-10);
  }

  .content table {
    display: block;
    overflow-x: auto;
    white-space: nowrap;
  }
}

/* Focus */
a:focus-visible,
button:focus-visible {
  outline: 2px solid var(--color-accent);
  outline-offset: 2px;
}

/* Print */
@media print {
  .sidebar,
  .mobile-header {
    display: none;
  }

  .main {
    margin-left: 0;
  }
}