/* ==========================================================
   AIEP Hub � global.css
   Uses Primer CSS (vendor/primer.css) exclusively.
   Zero AIEP design-system imports. Zero brand overrides.
   Layout-only rules to wire up the two-column shell.
   ========================================================== */

/* -- Body font -------------------------------------------- */
/* Primer does not set font-family on body; without this, nav,
   header, footer and anything outside .markdown-body falls back
   to the browser default (Times New Roman on most platforms).
   This matches the stack used by github-markdown.css.          */
body {
  font-family: -apple-system, BlinkMacSystemFont, "Segoe UI", "Noto Sans",
    Helvetica, Arial, sans-serif, "Apple Color Emoji", "Segoe UI Emoji";
  font-size: var(--h4-size, 1rem);
  line-height: 1.5;
  color: var(--fgColor-default, var(--color-fg-default, #1f2328));
  background-color: var(--bgColor-default, var(--color-canvas-default, #ffffff));
}

/* -- Images / SVG ------------------------------------------ */
img,
svg {
  display: block;
  max-width: 100%;
}

/* -- Fix github-markdown.css fgColor-accent override ------ */
/* github-markdown.css sets --fgColor-accent: Highlight (a CSS
   system color) inside .markdown-body, which overrides primer.css's
   correct value of #0969da. Re-pin it to the primer variable.   */
.markdown-body {
  --fgColor-accent: var(--color-accent-fg, #0969da);
}

/* -- Header: sticky + z-index above sidebar --------------- */
/* Primer .Header has z-index:32; sidebar is z-index:50;     */
/* so we lift the header to 100.                             */
.Header {
  position: sticky;
  top: 0;
  z-index: 100;
}

/* Mobile hamburger button inside Primer Header */
.Header .nav-toggle {
  display: none;
  background: none;
  border: 1px solid rgba(255, 255, 255, 0.3);
  padding: 4px 10px;
  font-size: 1rem;
  cursor: pointer;
  border-radius: 6px;
  color: inherit;
}

/* -- Two-column shell -------------------------------------- */
.site-body {
  display: block;
}

/* -- Fixed left sidebar ------------------------------------ */
.sidebar {
  position: fixed;
  top: 0;
  left: 0;
  width: 260px;
  height: 100vh;
  padding-top: 52px;
  /* Primer Header height */
  padding-bottom: 40px;
  border-right: 1px solid var(--borderColor-default, var(--color-border-default, #d1d9e0));
  overflow-y: auto;
  overflow-x: hidden;
  background-color: var(--bgColor-muted, var(--color-canvas-subtle, #f6f8fa));
  z-index: 50;
}

/* Slim scrollbar � match GitHub sidebar feel */
.sidebar::-webkit-scrollbar {
  width: 3px;
}

.sidebar::-webkit-scrollbar-thumb {
  background: var(--borderColor-default, var(--color-border-default));
  border-radius: 3px;
}

/* -- Nav section wrappers ---------------------------------- */
.nav-section {
  padding: 0 0 8px;
  border-top: 1px solid var(--borderColor-muted, var(--color-border-muted, #d8dee4));
}

.nav-section:first-child {
  border-top: none;
  padding-top: 8px;
}

/* Static section heading (e.g. "Understand") */
.nav-section-label {
  display: block;
  padding: 12px 16px 4px;
  font-size: var(--h6-size, 0.75rem);
  font-weight: var(--base-text-weight-semibold, 600);
  text-transform: uppercase;
  letter-spacing: 0.04em;
  color: var(--fgColor-muted, var(--color-fg-muted));
}

/* Collapsible section toggle */
.nav-section-toggle {
  display: flex;
  align-items: center;
  justify-content: space-between;
  width: 100%;
  padding: 10px 14px 10px 16px;
  background: none;
  border: none;
  cursor: pointer;
  font-size: var(--h6-size, 0.75rem);
  font-weight: var(--base-text-weight-semibold, 600);
  text-transform: uppercase;
  letter-spacing: 0.04em;
  color: var(--fgColor-muted, var(--color-fg-muted));
  line-height: 1.5;
}

.nav-section-toggle:hover {
  color: var(--fgColor-default, var(--color-fg-default));
}

/* Chevron rotates when open */
.nav-chevron {
  flex-shrink: 0;
  transition: transform 0.2s ease;
  color: var(--fgColor-muted, var(--color-fg-muted));
}

.nav-section.is-open .nav-chevron {
  transform: rotate(180deg);
}

/* Nav items list */
.nav-section-items {
  list-style: none;
  margin: 0;
  padding: 0 0 4px;
}

.nav-section-items[hidden] {
  display: none;
}

.nav-section-items li {
  margin: 0;
}

/* -- Nav links --------------------------------------------- */
.nav-link {
  display: block;
  padding: 5px 16px 5px 14px;
  font-size: var(--body-font-size, 0.875rem);
  font-weight: var(--base-text-weight-normal, 400);
  color: var(--fgColor-default, var(--color-fg-default));
  border-left: 2px solid transparent;
  background: transparent;
  text-decoration: none;
  line-height: 1.5;
}

.nav-link:hover {
  background-color: rgba(0, 0, 0, 0.05);
  border-left-color: var(--borderColor-default, var(--color-border-default));
  color: var(--fgColor-default, var(--color-fg-default));
  text-decoration: none;
}

.nav-link.active {
  border-left-color: var(--fgColor-accent, var(--color-accent-fg));
  color: var(--fgColor-default, var(--color-fg-default));
  font-weight: var(--base-text-weight-semibold, 600);
  background-color: rgba(0, 0, 0, 0.05);
}

/* -- Content offset (right of fixed sidebar) --------------- */
.page-offset {
  margin-left: 260px;
  display: flex;
  flex-direction: column;
  min-height: calc(100vh - 52px);
}

/* -- Main content — markdown-body provides the typography -- */
.main-content {
  flex: 1;
  padding: 32px 56px 64px;
  max-width: 900px;
  width: 100%;
}

/* github-markdown.css sets background-color on .markdown-body;
   keep it transparent so the page canvas shows through.        */
.markdown-body {
  background-color: transparent !important;
}

/* Tables: horizontally scrollable when wider than container */
.main-content .markdown-body table {
  display: block;
  overflow-x: auto;
  -webkit-overflow-scrolling: touch;
}

/* -- Get-involved bar -------------------------------------- */
.get-involved {
  border-top: 1px solid var(--borderColor-default, var(--color-border-default));
  background-color: var(--bgColor-muted, var(--color-canvas-subtle));
  padding: 11px 56px;
  font-size: var(--h6-size, 0.75rem);
  color: var(--fgColor-muted, var(--color-fg-muted));
}

.get-involved-inner {
  display: flex;
  gap: 6px;
  flex-wrap: wrap;
  align-items: center;
}

.get-involved a {
  color: var(--fgColor-accent, var(--color-accent-fg));
}

.get-involved a:hover {
  text-decoration: underline;
}

/* -- Footer ------------------------------------------------ */
.footer {
  border-top: 1px solid var(--borderColor-default, var(--color-border-default));
  background-color: var(--bgColor-muted, var(--color-canvas-subtle));
}

.footer .container {
  max-width: 100%;
  padding: 13px 56px;
}

.footer-line {
  display: flex;
  gap: 10px;
  flex-wrap: wrap;
  align-items: center;
  font-size: var(--h6-size, 0.75rem);
  color: var(--fgColor-muted, var(--color-fg-muted));
}

.footer-line--spaced {
  margin-top: 10px;
}

.footer-line a {
  color: var(--fgColor-muted, var(--color-fg-muted));
}

/* -- CTA buttons (→ links) — elevated pill style all screens -- */
.main-content .markdown-body .cta-btn {
  display: inline-block;
  padding: 10px 20px;
  background: var(--bgColor-default, #fff);
  color: var(--fgColor-accent, var(--color-accent-fg, #0969da));
  border: 1px solid var(--borderColor-default, var(--color-border-default, #d1d9e0));
  border-radius: 28px;
  box-shadow: 0 2px 8px rgba(0, 0, 0, 0.08);
  font-weight: 600;
  text-decoration: none;
  transition: box-shadow 0.15s, transform 0.1s;
  margin: 12px 0;
}

.main-content .markdown-body .cta-btn:hover {
  box-shadow: 0 4px 16px rgba(0, 0, 0, 0.14);
  transform: translateY(-1px);
  text-decoration: none;
}

.main-content .markdown-body .cta-btn:active {
  transform: scale(0.97);
}

/* -- Tablet ------------------------------------------------ */
@media (max-width: 1100px) {
  .main-content {
    padding: 28px 36px 56px;
    max-width: 100%;
    width: 100%;
  }

  .get-involved {
    padding: 11px 36px;
  }

  .footer .container {
    padding: 13px 36px;
  }
}

/* -- Mobile ------------------------------------------------ */
@media (max-width: 700px) {
  .Header .nav-toggle {
    display: block;
  }

  .sidebar {
    left: -260px;
    top: 0;
    padding-top: 56px;
    z-index: 300;
    transition: left 0.2s ease;
    background-color: var(--bgColor-muted, var(--color-canvas-subtle, #f6f8fa));
  }

  .sidebar.open {
    left: 0;
    box-shadow: 4px 0 24px rgba(0, 0, 0, 0.18);
  }

  /* Backdrop overlay when sidebar is open */
  .sidebar-backdrop {
    display: none;
    position: fixed;
    inset: 0;
    background: var(--c-overlay, rgba(0, 0, 0, 0.35));
    z-index: 299;
  }

  .sidebar-backdrop.open {
    display: block;
  }

  .page-offset {
    margin-left: 0;
  }

  /* Bump body text for mobile readability */
  body {
    font-size: 1.0625rem;
  }

  .main-content {
    padding: 20px 14px 80px;
    max-width: 100%;
    box-sizing: border-box;
    overflow-x: hidden;
  }

  /* Headings: tighter on small screens */
  .main-content .markdown-body h1 {
    font-size: 1.5rem;
    word-break: break-word;
  }

  .main-content .markdown-body h2 {
    font-size: 1.25rem;
    word-break: break-word;
  }

  .main-content .markdown-body h3 {
    font-size: 1.1rem;
    word-break: break-word;
  }

  /* Tables: horizontal scroll with momentum, prevent blowout */
  .main-content .markdown-body table {
    font-size: 0.8125rem;
    display: block;
    overflow-x: auto;
    -webkit-overflow-scrolling: touch;
    white-space: nowrap;
    max-width: 100%;
  }

  .main-content .markdown-body table th,
  .main-content .markdown-body table td {
    white-space: normal;
    min-width: 80px;
    word-break: break-word;
  }

  /* Code blocks: horizontal scroll, no blowout */
  .main-content .markdown-body pre {
    overflow-x: auto;
    -webkit-overflow-scrolling: touch;
    max-width: calc(100vw - 28px);
    font-size: 0.8125rem;
  }

  .main-content .markdown-body code {
    word-break: break-word;
  }

  /* Inline images constrained */
  .main-content .markdown-body img {
    max-width: 100%;
    height: auto;
  }

  /* Long links / URLs don't blow out layout */
  .main-content .markdown-body a {
    word-break: break-word;
  }

  /* Paragraphs: readable line length */
  .main-content .markdown-body p {
    overflow-wrap: break-word;
  }

  /* -- CTA links styled as floating pill buttons -- */
  .main-content .markdown-body .cta-btn {
    display: block;
    width: fit-content;
    max-width: calc(100% - 24px);
    margin: 20px 0;
    padding: 12px 22px;
    background: var(--bgColor-default, #fff);
    color: var(--fgColor-accent, var(--color-accent-fg, #0969da));
    border: 1px solid var(--borderColor-default, var(--color-border-default, #d1d9e0));
    border-radius: 28px;
    box-shadow: 0 2px 10px rgba(0, 0, 0, 0.10);
    font-size: 0.9375rem;
    font-weight: 600;
    text-decoration: none;
    text-align: center;
    line-height: 1.4;
    transition: box-shadow 0.15s, transform 0.1s;
    -webkit-tap-highlight-color: transparent;
  }

  .main-content .markdown-body .cta-btn:hover {
    box-shadow: 0 4px 16px rgba(0, 0, 0, 0.16);
    transform: translateY(-1px);
    text-decoration: none;
  }

  .main-content .markdown-body .cta-btn:active {
    transform: scale(0.97);
    box-shadow: 0 1px 6px rgba(0, 0, 0, 0.12);
  }

  /* Nav links: larger touch targets on mobile sidebar */
  .nav-link {
    padding: 9px 16px 9px 14px;
    font-size: 1rem;
    min-height: 44px;
    display: flex;
    align-items: center;
  }

  .get-involved {
    padding: 11px 18px;
  }

  .footer .container {
    padding: 13px 18px;
  }
}