/* ==========================================================================
   Trading docs — strict, elegant theme in blue + burgundy.
   Inspired by Material for MkDocs but kept self-contained.
   ========================================================================== */

/* ----- Design tokens --------------------------------------------------- */

:root {
  /* Layout */
  --header-height: 56px;
  --sidebar-width: 280px;
  --toc-width: 232px;
  --content-max: 760px;
  --gutter: 2rem;

  /* Type */
  --font-sans: "Inter", -apple-system, BlinkMacSystemFont, "Segoe UI",
               Roboto, "Helvetica Neue", Arial, sans-serif;
  --font-serif: "Source Serif Pro", Georgia, "Times New Roman", serif;
  --font-mono: "JetBrains Mono", "SF Mono", Menlo, Consolas,
               "Liberation Mono", monospace;

  --fs-base: 16px;
  --lh-base: 1.65;

  /* Palette — strict navy + burgundy */
  --c-primary:        #1a2a5c;     /* deep navy */
  --c-primary-dark:   #0e1a3d;
  --c-primary-light:  #2d3f7a;
  --c-primary-soft:   #eef0f7;
  --c-primary-on:     #ffffff;

  --c-accent:         #7a1834;     /* burgundy */
  --c-accent-dark:    #4f0e21;
  --c-accent-light:   #a64055;
  --c-accent-soft:    #f7eaee;
  --c-accent-on:      #ffffff;

  --c-bg:             #fafafa;
  --c-surface:        #ffffff;
  --c-surface-alt:    #f4f5f8;

  --c-text:           #1a1d24;
  --c-text-muted:     #555a66;
  --c-text-faint:     #8a8f99;

  --c-border:         #e3e5ea;
  --c-border-strong:  #c8ccd4;

  --c-link:           var(--c-primary);
  --c-link-hover:     var(--c-accent);

  --c-code-bg:        #f4f5f8;
  --c-code-text:      #2a2f3a;
  --c-code-border:    #e3e5ea;
  --c-pre-bg:         #15193a;
  --c-pre-text:       #e6e9f4;

  --shadow-sm: 0 1px 2px rgba(15, 20, 50, 0.06);
  --shadow-md: 0 2px 8px rgba(15, 20, 50, 0.08);
  --shadow-lg: 0 8px 24px rgba(15, 20, 50, 0.12);

  --radius-sm: 4px;
  --radius-md: 6px;
  --radius-lg: 10px;

  --transition-fast: 120ms ease;
  --transition: 200ms ease;
}

/* ----- Reset & base ---------------------------------------------------- */

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

html { font-size: var(--fs-base); -webkit-text-size-adjust: 100%; }

body {
  margin: 0;
  font-family: var(--font-sans);
  font-size: 1rem;
  line-height: var(--lh-base);
  color: var(--c-text);
  background-color: var(--c-bg);
  -webkit-font-smoothing: antialiased;
  -moz-osx-font-smoothing: grayscale;
}

img { max-width: 100%; height: auto; display: inline-block; }

a {
  color: var(--c-link);
  text-decoration: none;
  border-bottom: 1px solid transparent;
  transition: color var(--transition-fast),
              border-color var(--transition-fast);
}
a:hover {
  color: var(--c-link-hover);
  border-bottom-color: currentColor;
}

hr {
  height: 1px;
  background-color: var(--c-border);
  border: 0;
  margin: 2rem 0;
}

/* ----- Header ---------------------------------------------------------- */

.site-header {
  position: fixed;
  top: 0;
  left: 0;
  right: 0;
  height: var(--header-height);
  background: linear-gradient(135deg,
              var(--c-primary) 0%,
              var(--c-primary-dark) 100%);
  color: var(--c-primary-on);
  display: flex;
  align-items: center;
  padding: 0 1.25rem;
  box-shadow: var(--shadow-md);
  z-index: 100;
}

.site-title {
  color: var(--c-primary-on);
  font-weight: 600;
  font-size: 1.05rem;
  letter-spacing: 0.02em;
  border-bottom: none;
  display: inline-flex;
  align-items: baseline;
  gap: 0.4em;
}
.site-title::before {
  content: "";
  display: inline-block;
  width: 8px;
  height: 18px;
  background: var(--c-accent-light);
  border-radius: 1px;
  margin-right: 0.5rem;
  transform: translateY(2px);
}
.site-title:hover { color: var(--c-primary-on); border-bottom: none; }

.site-title-sub {
  color: rgba(255, 255, 255, 0.7);
  font-weight: 400;
  font-size: 0.95em;
}

/* GitHub repo badge */
.repo-link {
  display: inline-flex;
  align-items: center;
  gap: 0.6rem;
  margin-left: auto;
  padding: 0.35rem 0.7rem;
  border: 1px solid rgba(255, 255, 255, 0.22);
  border-radius: var(--radius-md);
  background: rgba(255, 255, 255, 0.06);
  color: var(--c-primary-on);
  font-size: 0.84rem;
  line-height: 1;
  text-decoration: none;
  border-bottom: none;
  transition: background var(--transition-fast),
              border-color var(--transition-fast),
              transform var(--transition-fast);
}
.repo-link:hover {
  background: rgba(255, 255, 255, 0.14);
  border-color: rgba(255, 255, 255, 0.45);
  color: var(--c-primary-on);
  border-bottom: none;
  transform: translateY(-1px);
}
.repo-link:active { transform: translateY(0); }

.repo-icon {
  width: 18px;
  height: 18px;
  fill: currentColor;
  flex-shrink: 0;
}

.repo-text {
  display: inline-flex;
  align-items: center;
  gap: 0.55rem;
}

.repo-name {
  font-weight: 500;
  letter-spacing: 0.01em;
}

.repo-stats {
  display: inline-flex;
  gap: 0.55rem;
  padding-left: 0.6rem;
  border-left: 1px solid rgba(255, 255, 255, 0.22);
}

.repo-stat {
  display: inline-flex;
  align-items: center;
  gap: 0.25rem;
  font-variant-numeric: tabular-nums;
  font-size: 0.78rem;
  opacity: 0.92;
}

.repo-stat-icon {
  width: 12px;
  height: 12px;
  fill: currentColor;
  flex-shrink: 0;
}

@media (max-width: 720px) {
  .repo-link { padding: 0.35rem 0.55rem; }
  .repo-text { display: none; }
}

/* Hamburger (mobile only) */
.nav-toggle-label {
  display: none;
  cursor: pointer;
  padding: 8px;
  margin-right: 0.5rem;
  user-select: none;
}
.nav-toggle-bar {
  display: block;
  width: 22px;
  height: 2px;
  background: var(--c-primary-on);
  margin: 4px 0;
  border-radius: 2px;
  transition: transform var(--transition);
}
.nav-toggle { position: absolute; left: -9999px; }

/* ----- Sidebar --------------------------------------------------------- */

.site-sidebar {
  position: fixed;
  top: var(--header-height);
  bottom: 0;
  left: 0;
  width: var(--sidebar-width);
  background-color: var(--c-surface);
  border-right: 1px solid var(--c-border);
  overflow-y: auto;
  padding: 1.5rem 0 2rem;
  z-index: 50;
  transition: transform var(--transition);
}

.site-nav { padding: 0 1.25rem; }

.nav-brand { display: none; }   /* duplicated by header on desktop */

/* ----- Sidebar navigation tree ----------------------------------------- */

.nav-tree {
  list-style: none;
  margin: 0;
  padding: 0;
}

/* Nested levels are indented and share a subtle guide line. */
.nav-tree .nav-tree {
  margin-left: 0.55rem;
  padding-left: 0.35rem;
  border-left: 1px solid var(--c-border);
}

.nav-tree li { margin: 0; }

.nav-link,
.nav-section-label {
  display: block;
  padding: 0.35rem 0.5rem;
  font-size: 0.9rem;
  line-height: 1.35;
  border-radius: 0 var(--radius-sm) var(--radius-sm) 0;
}

.nav-link {
  color: var(--c-text);
  border-left: 2px solid transparent;
  transition: background-color var(--transition-fast),
              color var(--transition-fast),
              border-color var(--transition-fast);
}

.nav-link:hover {
  background-color: var(--c-primary-soft);
  color: var(--c-primary);
  border-left-color: var(--c-accent);
}

.nav-active {
  background-color: var(--c-primary-soft);
  color: var(--c-primary);
  border-left-color: var(--c-accent);
  font-weight: 600;
}

/* Non-navigable directory heading (a section with no index page). */
.nav-section-label {
  color: var(--c-text);
  font-weight: 600;
}

/* Foldable branch: replace the default disclosure marker with a rotating
   triangle so the caret sits inline with the label. */
.nav-branch > details > summary {
  list-style: none;
  cursor: pointer;
  display: flex;
  align-items: center;
  gap: 0.15rem;
}

.nav-branch > details > summary::-webkit-details-marker { display: none; }

.nav-branch > details > summary::before {
  content: "\25B8";                /* ▸ */
  flex: 0 0 auto;
  width: 0.9rem;
  text-align: center;
  font-size: 0.7rem;
  color: var(--c-accent);
  transition: transform var(--transition-fast);
}

.nav-branch > details[open] > summary::before {
  transform: rotate(90deg);
}

.nav-branch > details > summary .nav-link,
.nav-branch > details > summary .nav-section-label {
  flex: 1 1 auto;
  min-width: 0;
}

/* ----- Main content layout --------------------------------------------- */

.site-main-wrap {
  margin-left: var(--sidebar-width);
  padding-top: var(--header-height);
  display: grid;
  grid-template-columns: minmax(0, 1fr) var(--toc-width);
  gap: var(--gutter);
  align-items: start;
}

.site-main {
  max-width: var(--content-max);
  margin: 0 auto;
  padding: 2.5rem 2rem 4rem;
  min-width: 0;
}

/* ----- Page TOC (right rail) ------------------------------------------- */

.page-toc-wrap {
  position: sticky;
  top: calc(var(--header-height) + 2.5rem);
  max-height: calc(100vh - var(--header-height) - 4rem);
  overflow-y: auto;
  padding: 0 1.5rem 2rem 0;
}

.page-toc {
  font-size: 0.85rem;
  border-left: 2px solid var(--c-border);
  padding-left: 1rem;
}

.page-toc-title {
  font-size: 0.72rem;
  font-weight: 700;
  text-transform: uppercase;
  letter-spacing: 0.1em;
  color: var(--c-accent);
  margin-bottom: 0.6rem;
}

.page-toc ul,
.page-toc-list,
.page-toc .toc {
  list-style: none;
  margin: 0;
  padding: 0;
}

.page-toc ul ul,
.page-toc-list ul,
.page-toc .toc ul {
  padding-left: 0.85rem;
  margin-top: 0.25rem;
}

.page-toc li {
  margin: 0.25rem 0;
  line-height: 1.4;
}

.page-toc a {
  color: var(--c-text-muted);
  border-bottom: none;
  display: block;
  padding: 0.1rem 0;
}

.page-toc a:hover {
  color: var(--c-accent);
}

/* ----- Footer ---------------------------------------------------------- */

.site-footer {
  margin-left: var(--sidebar-width);
  padding: 1.5rem 2rem;
  border-top: 1px solid var(--c-border);
  color: var(--c-text-faint);
  font-size: 0.85rem;
  text-align: center;
}

.footer-meta { margin: 0; }

/* ----- Typography ------------------------------------------------------ */

.site-main h1,
.site-main h2,
.site-main h3,
.site-main h4,
.site-main h5,
.site-main h6 {
  font-family: var(--font-serif);
  font-weight: 700;
  color: var(--c-primary-dark);
  line-height: 1.25;
  margin: 2rem 0 1rem;
  scroll-margin-top: calc(var(--header-height) + 1rem);
}

.site-main h1 {
  font-size: 2.1rem;
  margin-top: 0;
  padding-bottom: 0.6rem;
  border-bottom: 3px solid var(--c-accent);
  display: inline-block;
  padding-right: 1rem;
}

.site-main h2 {
  font-size: 1.55rem;
  padding-bottom: 0.35rem;
  border-bottom: 1px solid var(--c-border);
}

.site-main h3 { font-size: 1.25rem; }
.site-main h4 { font-size: 1.05rem; color: var(--c-accent-dark); }

.site-main p { margin: 0.85rem 0; }

.site-main strong { color: var(--c-primary-dark); }

.site-main blockquote {
  margin: 1.25rem 0;
  padding: 0.8rem 1.25rem;
  border-left: 4px solid var(--c-accent);
  background: var(--c-accent-soft);
  color: var(--c-text);
  border-radius: 0 var(--radius-md) var(--radius-md) 0;
}
.site-main blockquote p:first-child { margin-top: 0; }
.site-main blockquote p:last-child  { margin-bottom: 0; }

/* Anchor link beside headings */
.anchor {
  color: var(--c-text-faint);
  font-weight: 400;
  margin-left: 0.4rem;
  border-bottom: none;
  opacity: 0;
  transition: opacity var(--transition-fast);
}
.site-main h1:hover .anchor,
.site-main h2:hover .anchor,
.site-main h3:hover .anchor,
.site-main h4:hover .anchor { opacity: 1; }
.anchor:hover { color: var(--c-accent); }

/* ----- Lists ----------------------------------------------------------- */

.site-main ul,
.site-main ol {
  padding-left: 1.5rem;
  margin: 0.85rem 0;
}
.site-main li { margin: 0.3rem 0; }

.site-main li > ul,
.site-main li > ol { margin: 0.3rem 0; }

/* ----- Tables ---------------------------------------------------------- */

.site-main table {
  width: 100%;
  border-collapse: collapse;
  margin: 1.25rem 0;
  font-size: 0.92rem;
  background: var(--c-surface);
  box-shadow: var(--shadow-sm);
  border-radius: var(--radius-md);
  overflow: hidden;
}

.site-main thead {
  background: var(--c-primary);
  color: var(--c-primary-on);
}

.site-main th,
.site-main td {
  padding: 0.6rem 0.9rem;
  text-align: left;
  border-bottom: 1px solid var(--c-border);
}

.site-main th {
  font-weight: 600;
  letter-spacing: 0.02em;
  border-bottom-color: var(--c-primary-dark);
}

.site-main tbody tr:nth-child(even) { background: var(--c-surface-alt); }
.site-main tbody tr:hover { background: var(--c-primary-soft); }

.site-main td:first-child { font-variant-numeric: tabular-nums; }

/* ----- Code ------------------------------------------------------------ */

.site-main code,
.site-main kbd {
  font-family: var(--font-mono);
  font-size: 0.88em;
}

.site-main :not(pre) > code {
  background: var(--c-code-bg);
  color: var(--c-accent-dark);
  padding: 0.12em 0.4em;
  border-radius: var(--radius-sm);
  border: 1px solid var(--c-code-border);
  white-space: nowrap;
}

.site-main pre {
  background: var(--c-pre-bg);
  color: var(--c-pre-text);
  padding: 1rem 1.25rem;
  border-radius: var(--radius-md);
  overflow-x: auto;
  font-size: 0.85rem;
  line-height: 1.55;
  margin: 1.25rem 0;
  box-shadow: var(--shadow-sm);
  border-left: 3px solid var(--c-accent);
}

.site-main pre code {
  background: transparent;
  color: inherit;
  padding: 0;
  border: 0;
  white-space: pre;
  font-size: inherit;
}

.site-main kbd {
  background: var(--c-surface-alt);
  border: 1px solid var(--c-border-strong);
  border-bottom-width: 2px;
  border-radius: var(--radius-sm);
  padding: 0.1em 0.45em;
  font-size: 0.82em;
  color: var(--c-text);
}

/* ----- Footnotes ------------------------------------------------------- */

.footnotes {
  margin-top: 3rem;
  padding-top: 1rem;
  font-size: 0.9rem;
  color: var(--c-text-muted);
}
.footnotes hr {
  margin: 0 0 1rem;
  background: var(--c-accent);
  height: 2px;
  width: 60px;
}
a.footnote-ref {
  border-bottom: none;
  font-size: 0.75em;
  vertical-align: super;
  color: var(--c-accent);
  padding: 0 0.15em;
}

/* ----- Responsive ------------------------------------------------------ */

@media (max-width: 1180px) {
  :root { --toc-width: 0px; }
  .page-toc-wrap { display: none; }
  .site-main-wrap { grid-template-columns: minmax(0, 1fr); }
}

@media (max-width: 860px) {
  :root { --sidebar-width: 0px; }

  .nav-toggle-label { display: inline-block; }

  .site-sidebar {
    width: 280px;
    transform: translateX(-100%);
    box-shadow: var(--shadow-lg);
  }
  .nav-toggle:checked ~ .site-sidebar { transform: translateX(0); }

  .nav-overlay {
    position: fixed;
    inset: var(--header-height) 0 0 0;
    background: rgba(15, 20, 50, 0.5);
    opacity: 0;
    pointer-events: none;
    transition: opacity var(--transition);
    z-index: 40;
  }
  .nav-toggle:checked ~ .nav-overlay {
    opacity: 1;
    pointer-events: auto;
  }

  .site-main-wrap,
  .site-footer { margin-left: 0; }

  .site-main {
    padding: 1.5rem 1.25rem 3rem;
  }

  .site-main h1 { font-size: 1.7rem; }
  .site-main h2 { font-size: 1.35rem; }
}

@media (min-width: 861px) {
  .nav-overlay { display: none; }
}

/* ----- Print ----------------------------------------------------------- */

@media print {
  .site-header,
  .site-sidebar,
  .page-toc-wrap,
  .nav-toggle-label { display: none; }

  .site-main-wrap,
  .site-footer { margin-left: 0; }

  .site-main {
    max-width: none;
    padding: 0;
  }

  body { background: white; }

  a { color: var(--c-text); border-bottom: none; }
}