/* ==========================================================================
   Purl Knowledge Portal
   ========================================================================== */

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

:root {
  --sidebar-width: 240px;
  --content-max: 860px;
  --font-sans: -apple-system, BlinkMacSystemFont, "Segoe UI", Roboto, Helvetica, Arial, sans-serif;
  --font-mono: "SF Mono", "Fira Code", "Fira Mono", Menlo, Consolas, monospace;

  /* Light theme (default) */
  --bg: #ffffff;
  --bg-sidebar: #f5f5f7;
  --bg-code: #f0f0f2;
  --bg-code-block: #1e1e2e;
  --text: #1d1d1f;
  --text-secondary: #6e6e73;
  --text-code-block: #cdd6f4;
  --border: #d2d2d7;
  --link: #0066cc;
  --link-hover: #0040a0;
  --nav-active: #0066cc;
  --nav-active-bg: #e8f0fe;
  --table-stripe: #f9f9fb;
  --table-border: #e5e5ea;
  --toc-bg: #f5f5f7;
}

/* Dark via system preference */
@media (prefers-color-scheme: dark) {
  :root:not([data-theme="light"]) {
    --bg: #1a1a1e;
    --bg-sidebar: #141416;
    --bg-code: #2a2a2e;
    --bg-code-block: #11111b;
    --text: #e5e5ea;
    --text-secondary: #98989d;
    --text-code-block: #cdd6f4;
    --border: #38383a;
    --link: #5ab4f5;
    --link-hover: #7cc4f8;
    --nav-active: #5ab4f5;
    --nav-active-bg: #1c2a3a;
    --table-stripe: #1e1e22;
    --table-border: #2c2c2e;
    --toc-bg: #1e1e22;
  }
}

/* Dark via manual toggle */
:root[data-theme="dark"] {
  --bg: #1a1a1e;
  --bg-sidebar: #141416;
  --bg-code: #2a2a2e;
  --bg-code-block: #11111b;
  --text: #e5e5ea;
  --text-secondary: #98989d;
  --text-code-block: #cdd6f4;
  --border: #38383a;
  --link: #5ab4f5;
  --link-hover: #7cc4f8;
  --nav-active: #5ab4f5;
  --nav-active-bg: #1c2a3a;
  --table-stripe: #1e1e22;
  --table-border: #2c2c2e;
  --toc-bg: #1e1e22;
}

html {
  font-size: 15px;
  -webkit-font-smoothing: antialiased;
}

body {
  font-family: var(--font-sans);
  color: var(--text);
  background: var(--bg);
  line-height: 1.65;
  display: flex;
  min-height: 100vh;
}

/* ==========================================================================
   Sidebar
   ========================================================================== */

.sidebar {
  position: fixed;
  top: 0;
  left: 0;
  width: var(--sidebar-width);
  height: 100vh;
  background: var(--bg-sidebar);
  border-right: 1px solid var(--border);
  display: flex;
  flex-direction: column;
  overflow-y: auto;
  z-index: 10;
}

.sidebar-header {
  padding: 16px 16px 12px;
  border-bottom: 1px solid var(--border);
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 8px;
}

.logo {
  display: flex;
  align-items: center;
  gap: 8px;
  text-decoration: none;
  color: var(--text);
}

.logo-img {
  width: 28px;
  height: 28px;
}

.logo span {
  font-size: 0.95rem;
  font-weight: 700;
  letter-spacing: -0.02em;
}

/* Theme toggle */
.theme-toggle {
  background: none;
  border: 1px solid var(--border);
  border-radius: 6px;
  width: 30px;
  height: 30px;
  cursor: pointer;
  display: flex;
  align-items: center;
  justify-content: center;
  color: var(--text-secondary);
  flex-shrink: 0;
  transition: color 0.15s, border-color 0.15s;
}

.theme-toggle:hover {
  color: var(--text);
  border-color: var(--text-secondary);
}

/* Show sun in dark mode, moon in light mode */
.icon-moon { display: inline; }
.icon-sun { display: none; }

@media (prefers-color-scheme: dark) {
  :root:not([data-theme="light"]) .icon-moon { display: none; }
  :root:not([data-theme="light"]) .icon-sun { display: inline; }
}

:root[data-theme="dark"] .icon-moon { display: none; }
:root[data-theme="dark"] .icon-sun { display: inline; }
:root[data-theme="light"] .icon-moon { display: inline; }
:root[data-theme="light"] .icon-sun { display: none; }

/* Sidebar links */
.sidebar-links {
  display: flex;
  flex-direction: column;
  padding: 8px 0;
  flex: 1;
}

.sidebar-links a {
  display: block;
  padding: 6px 16px;
  color: var(--text-secondary);
  text-decoration: none;
  font-size: 0.87rem;
  font-weight: 500;
  transition: color 0.15s, background 0.15s;
}

.sidebar-links a:hover {
  color: var(--text);
  background: var(--nav-active-bg);
}

.sidebar-links a.active {
  color: var(--nav-active);
  background: var(--nav-active-bg);
  font-weight: 600;
}

/* Subsection links (indented under parent) */
.sidebar-links a.sub {
  padding-left: 28px;
  font-size: 0.8rem;
  font-weight: 400;
  color: var(--text-secondary);
  opacity: 0.85;
}

.sidebar-links a.sub:hover {
  opacity: 1;
  color: var(--text);
}

/* ==========================================================================
   Content
   ========================================================================== */

.content {
  margin-left: var(--sidebar-width);
  flex: 1;
  min-width: 0;
}

article {
  max-width: var(--content-max);
  margin: 0 auto;
  padding: 40px 48px 80px;
}

/* ==========================================================================
   Table of Contents (in-page)
   ========================================================================== */

.toc {
  background: var(--toc-bg);
  border: 1px solid var(--border);
  border-radius: 8px;
  padding: 16px 20px;
  margin-bottom: 32px;
}

.toc h2 {
  font-size: 0.9rem;
  font-weight: 600;
  margin: 0 0 8px 0;
  padding: 0;
  border: none;
  color: var(--text-secondary);
  text-transform: uppercase;
  letter-spacing: 0.05em;
}

.toc ol {
  margin: 0;
  padding-left: 20px;
  columns: 2;
  column-gap: 24px;
}

.toc li {
  margin-bottom: 3px;
  font-size: 0.83rem;
  break-inside: avoid;
}

.toc a {
  color: var(--text-secondary);
}

.toc a:hover {
  color: var(--link);
}

/* ==========================================================================
   Typography
   ========================================================================== */

h1 {
  font-size: 2rem;
  font-weight: 700;
  margin-bottom: 16px;
  letter-spacing: -0.03em;
  line-height: 1.2;
}

h2 {
  font-size: 1.4rem;
  font-weight: 650;
  margin-top: 48px;
  margin-bottom: 12px;
  padding-bottom: 6px;
  border-bottom: 1px solid var(--border);
  letter-spacing: -0.02em;
}

h3 {
  font-size: 1.1rem;
  font-weight: 620;
  margin-top: 32px;
  margin-bottom: 8px;
}

h4 {
  font-size: 0.95rem;
  font-weight: 600;
  margin-top: 24px;
  margin-bottom: 6px;
}

p {
  margin-bottom: 12px;
}

a {
  color: var(--link);
  text-decoration: none;
}

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

strong {
  font-weight: 600;
}

hr {
  border: none;
  border-top: 1px solid var(--border);
  margin: 32px 0;
}

/* ==========================================================================
   Lists
   ========================================================================== */

ul, ol {
  margin-bottom: 12px;
  padding-left: 24px;
}

li {
  margin-bottom: 4px;
}

li > ul, li > ol {
  margin-top: 4px;
  margin-bottom: 4px;
}

/* ==========================================================================
   Code
   ========================================================================== */

code {
  font-family: var(--font-mono);
  font-size: 0.85em;
  background: var(--bg-code);
  padding: 2px 5px;
  border-radius: 4px;
}

pre {
  background: var(--bg-code-block);
  color: var(--text-code-block);
  padding: 16px 20px;
  border-radius: 8px;
  overflow-x: auto;
  margin-bottom: 16px;
  line-height: 1.5;
  font-size: 0.82rem;
}

pre code {
  background: none;
  padding: 0;
  border-radius: 0;
  color: inherit;
  font-size: inherit;
}

/* ==========================================================================
   Tables
   ========================================================================== */

table {
  width: 100%;
  border-collapse: collapse;
  margin-bottom: 16px;
  font-size: 0.87rem;
}

th {
  text-align: left;
  font-weight: 600;
  padding: 8px 12px;
  border-bottom: 2px solid var(--table-border);
}

td {
  padding: 7px 12px;
  border-bottom: 1px solid var(--table-border);
}

tr:nth-child(even) {
  background: var(--table-stripe);
}

/* ==========================================================================
   Blockquotes
   ========================================================================== */

blockquote {
  border-left: 3px solid var(--link);
  padding: 8px 16px;
  margin: 0 0 16px 0;
  color: var(--text-secondary);
}

blockquote p:last-child {
  margin-bottom: 0;
}

/* ==========================================================================
   Hamburger (mobile only)
   ========================================================================== */

.nav-hamburger {
  display: none;
  position: fixed;
  top: 12px;
  left: 12px;
  z-index: 20;
  width: 36px;
  height: 36px;
  cursor: pointer;
  flex-direction: column;
  justify-content: center;
  align-items: center;
  gap: 5px;
  background: var(--bg-sidebar);
  border: 1px solid var(--border);
  border-radius: 6px;
}

.nav-hamburger span {
  display: block;
  width: 18px;
  height: 2px;
  background: var(--text);
  transition: transform 0.2s;
}

/* ==========================================================================
   Responsive
   ========================================================================== */

@media (max-width: 768px) {
  .nav-hamburger {
    display: flex;
  }

  .sidebar {
    transform: translateX(-100%);
    transition: transform 0.25s ease;
  }

  #nav-toggle:checked ~ .sidebar {
    transform: translateX(0);
  }

  #nav-toggle:checked ~ .nav-hamburger span:nth-child(1) {
    transform: translateY(7px) rotate(45deg);
  }

  #nav-toggle:checked ~ .nav-hamburger span:nth-child(2) {
    opacity: 0;
  }

  #nav-toggle:checked ~ .nav-hamburger span:nth-child(3) {
    transform: translateY(-7px) rotate(-45deg);
  }

  .content {
    margin-left: 0;
  }

  article {
    padding: 56px 20px 60px;
  }

  .toc ol {
    columns: 1;
  }
}

/* ==========================================================================
   highlight.js overrides (Catppuccin Mocha-ish)
   ========================================================================== */

.hljs-keyword,
.hljs-selector-tag { color: #cba6f7; }
.hljs-string,
.hljs-addition { color: #a6e3a1; }
.hljs-number,
.hljs-literal { color: #fab387; }
.hljs-comment { color: #6c7086; font-style: italic; }
.hljs-built_in { color: #f38ba8; }
.hljs-type,
.hljs-params { color: #f9e2af; }
.hljs-attr,
.hljs-attribute { color: #89b4fa; }
.hljs-title { color: #89b4fa; font-weight: 600; }
.hljs-section { color: #89b4fa; font-weight: 700; }
.hljs-punctuation { color: #bac2de; }
.hljs-property { color: #89dceb; }
.hljs-deletion { color: #f38ba8; }
.hljs-emphasis { font-style: italic; }
.hljs-strong { font-weight: 700; }