:root {
  /* Brand tokens */
  --ctb-brand-50: #eef2ff;
  --ctb-brand-100: #e0e7ff;
  --ctb-brand-200: #c7d2fe;
  --ctb-brand-400: #818cf8;
  --ctb-brand-500: #6366f1;
  --ctb-brand-600: #4f46e5;
  --ctb-brand-700: #4338ca;
  --ctb-brand-900: #312e81;

  /* Surface radius and shadow scale */
  --ctb-radius-sm: 8px;
  --ctb-radius-md: 12px;
  --ctb-radius-lg: 18px;
  --ctb-shadow-sm: 0 2px 6px rgba(15, 23, 42, 0.08);
  --ctb-shadow-md: 0 10px 24px rgba(15, 23, 42, 0.12);
  --ctb-shadow-lg: 0 22px 56px rgba(15, 23, 42, 0.22);
}

[data-md-color-scheme="default"] {
  /* Material token mapping (light) */
  --md-default-fg-color: #1e293b;
  --md-default-fg-color--light: #475569;
  --md-default-fg-color--lighter: #64748b;
  --md-default-fg-color--lightest: rgba(100, 116, 139, 0.35);

  --md-default-bg-color: #f8fafc;
  --md-default-bg-color--light: #ffffff;
  --md-default-bg-color--lighter: #ffffff;
  --md-default-bg-color--lightest: #edf2f7;

  --md-primary-fg-color: #ffffff;
  --md-primary-fg-color--light: #ffffff;
  --md-primary-fg-color--dark: #eef2ff;

  --md-accent-fg-color: var(--ctb-brand-600);
  --md-accent-fg-color--transparent: rgba(99, 102, 241, 0.14);
  --md-typeset-a-color: var(--ctb-brand-700);

  --md-code-fg-color: #0f172a;
  --md-code-bg-color: #f1f5f9;
  --md-code-hl-color: rgba(99, 102, 241, 0.08);

  /* CTB scoped variables */
  --ctb-bg-page: #f8fafc;
  --ctb-bg-page-alt: #eef2f7;
  --ctb-bg-card: #ffffff;
  --ctb-bg-header: #ffffff;
  --ctb-bg-sidebar-start: #f7faff;
  --ctb-bg-sidebar-end: #eef4ff;
  --ctb-bg-sidebar: #f3f7ff;
  --ctb-bg-search: #ffffff;
  --ctb-border-soft: rgba(71, 85, 105, 0.22);
  --ctb-border-strong: rgba(71, 85, 105, 0.35);
  --ctb-text-main: #1e293b;
  --ctb-text-muted: #64748b;
  --ctb-text-inverse: #ffffff;
  --ctb-splash: none;
}

[data-md-color-scheme="slate"] {
  /* Material token mapping (dark) */
  --md-default-fg-color: #e2e8f0;
  --md-default-fg-color--light: #cbd5e1;
  --md-default-fg-color--lighter: #94a3b8;
  --md-default-fg-color--lightest: rgba(148, 163, 184, 0.35);

  --md-default-bg-color: #0b1326;
  --md-default-bg-color--light: #101b34;
  --md-default-bg-color--lighter: #12203e;
  --md-default-bg-color--lightest: #1a2a47;

  --md-primary-fg-color: #0f1a31;
  --md-primary-fg-color--light: #142444;
  --md-primary-fg-color--dark: #081226;

  --md-accent-fg-color: #a5b4fc;
  --md-accent-fg-color--transparent: rgba(129, 140, 248, 0.18);
  --md-typeset-a-color: #c7d2fe;

  --md-code-fg-color: #e2e8f0;
  --md-code-bg-color: #0a1122;
  --md-code-hl-color: rgba(129, 140, 248, 0.13);

  /* CTB scoped variables */
  --ctb-bg-page: #0b1326;
  --ctb-bg-page-alt: #0a1021;
  --ctb-bg-card: #101b34;
  --ctb-bg-header: #0c162c;
  --ctb-bg-sidebar-start: #0e1a34;
  --ctb-bg-sidebar-end: #11213f;
  --ctb-bg-sidebar: #0f1d38;
  --ctb-bg-search: #0b1730;
  --ctb-border-soft: rgba(148, 163, 184, 0.24);
  --ctb-border-strong: rgba(148, 163, 184, 0.4);
  --ctb-text-main: #e2e8f0;
  --ctb-text-muted: #94a3b8;
  --ctb-text-inverse: #0b1326;
  --ctb-splash: none;
}

html,
body {
  background: var(--ctb-bg-page);
}

.md-main {
  background: var(--ctb-bg-page);
}

/* Header and top controls */
.md-header {
  background: var(--ctb-bg-header);
  border-bottom: 1px solid var(--ctb-border-soft);
  box-shadow: 0 1px 0 rgba(255, 255, 255, 0.04) inset;
}

.md-header__title,
.md-header__topic,
.md-header .md-icon,
.md-header .md-header__button {
  color: var(--ctb-text-main);
}

.md-tabs {
  background: transparent;
  border-bottom: 1px solid var(--ctb-border-soft);
}

.md-tabs__link {
  color: var(--ctb-text-muted);
}

.md-tabs__link--active,
.md-tabs__link:hover {
  color: var(--ctb-text-main);
}

/* Sidebar and nav tree */
.md-sidebar--primary,
.md-sidebar--secondary {
  background: var(--ctb-bg-sidebar);
  border-right: 1px solid var(--ctb-border-soft);
}

.md-sidebar__scrollwrap,
.md-sidebar__inner {
  background: transparent;
}

.md-nav__title {
  position: sticky;
  top: 0;
  z-index: 2;
  background: var(--ctb-bg-sidebar);
  border-bottom: 1px solid var(--ctb-border-soft);
}

nav.md-nav--primary > .md-nav__title + .md-nav__list,
nav.md-nav--secondary > .md-nav__title + .md-nav__list {
  margin-top: 0;
}

.md-nav__link {
  color: var(--ctb-text-muted);
  border-radius: var(--ctb-radius-sm);
  padding: 0.3rem 0.45rem;
  transition:
    background-color 0.16s ease,
    color 0.16s ease;
}

.md-nav__link:hover,
.md-nav__link:focus-visible {
  color: var(--ctb-text-main);
  background-color: var(--md-accent-fg-color--transparent);
}

.md-nav__link--active,
.md-nav__item .md-nav__link--active {
  color: var(--ctb-text-main);
  font-weight: 700;
}

.md-nav__source {
  color: var(--ctb-text-muted);
  border-top: 1px solid var(--ctb-border-soft);
}

/* Search */
.md-search__form {
  background-color: var(--ctb-bg-search);
  border: 1px solid var(--ctb-border-soft);
  border-radius: 999px;
}

.md-search__input {
  color: var(--ctb-text-main);
}

.md-search__input::placeholder {
  color: var(--ctb-text-muted);
}

.md-search__icon,
.md-search__icon svg {
  color: var(--ctb-text-muted);
  fill: currentColor;
}

.md-search-result {
  border: 1px solid var(--ctb-border-soft);
  border-radius: var(--ctb-radius-md);
  background: var(--ctb-bg-card);
  box-shadow: var(--ctb-shadow-md);
}

/* Content typography */
.md-typeset {
  color: var(--ctb-text-main);
  line-height: 1.7;
}

.md-typeset h1,
.md-typeset h2,
.md-typeset h3,
.md-typeset h4 {
  color: var(--ctb-text-main);
  font-weight: 700;
  letter-spacing: 0;
}

.md-typeset h2,
.md-typeset h3 {
  scroll-margin-top: 5.2rem;
}

.md-typeset a {
  color: var(--md-typeset-a-color);
  text-underline-offset: 0.12em;
}

.md-typeset a:hover {
  color: var(--md-accent-fg-color);
}

.md-typeset hr {
  border-bottom-color: var(--ctb-border-soft);
}

/* Tables */
.md-typeset table:not([class]) {
  border-radius: var(--ctb-radius-md);
  overflow: hidden;
  border: 1px solid var(--ctb-border-soft);
  box-shadow: var(--ctb-shadow-sm);
}

.md-typeset table:not([class]) th {
  background: var(--md-accent-fg-color--transparent);
  color: var(--ctb-text-main);
  font-weight: 700;
}

.md-typeset table:not([class]) tr:hover {
  background: rgba(99, 102, 241, 0.06);
}

/* Code blocks and inline code */
.md-typeset code {
  border-radius: 6px;
  padding: 0.14em 0.35em;
  border: 1px solid var(--ctb-border-soft);
}

.md-typeset pre,
.md-typeset pre > code {
  border-radius: var(--ctb-radius-md);
  border: 1px solid var(--ctb-border-soft);
  box-shadow: var(--ctb-shadow-sm);
}

.md-typeset .md-clipboard {
  color: var(--ctb-text-muted);
}

.md-typeset .md-clipboard:hover {
  color: var(--ctb-text-main);
}

/* Admonitions and details */
.md-typeset .admonition,
.md-typeset details {
  border-radius: var(--ctb-radius-md);
  border: 1px solid var(--ctb-border-soft);
  background: var(--ctb-bg-card);
  padding: 0 !important;
  box-shadow: var(--ctb-shadow-sm);
  overflow: hidden;
}

.md-typeset .admonition > .admonition-title,
.md-typeset details > summary {
  display: block;
  width: 100%;
  box-sizing: border-box;
  margin: 0 !important;
  padding: 0.72rem 1rem 0.72rem 2.25rem;
  border-bottom: 1px solid var(--ctb-border-soft);
  background: linear-gradient(
    90deg,
    var(--md-accent-fg-color--transparent),
    transparent 72%
  );
  font-weight: 700;
}

.md-typeset .admonition > .admonition-title::before,
.md-typeset details > summary::before {
  top: 50%;
  transform: translateY(-50%);
}

.md-typeset .admonition > :not(.admonition-title),
.md-typeset details > :not(summary) {
  margin-top: 0;
  padding: 0.9rem 1rem 1rem;
}

.md-typeset .admonition > :not(.admonition-title):last-child,
.md-typeset details > :not(summary):last-child {
  margin-bottom: 0;
}

/*
Fallback for malformed admonitions where body text is not indented in Markdown.
Material renders the title inside .admonition and the body as the immediate next <p>.
This reconnects the body visually to create one card.
*/
.md-typeset .admonition:has(> .admonition-title:last-child) {
  margin-bottom: 0;
  border-bottom: 0;
  border-radius: var(--ctb-radius-md) var(--ctb-radius-md) 0 0;
}

.md-typeset .admonition:has(> .admonition-title:last-child) + p {
  margin-top: 0;
  margin-bottom: 1em;
  padding: 0.9rem 1rem 1rem;
  border: 1px solid var(--ctb-border-soft);
  border-top: 0;
  border-radius: 0 0 var(--ctb-radius-md) var(--ctb-radius-md);
  background: var(--ctb-bg-card);
  box-shadow: var(--ctb-shadow-sm);
}

/* Buttons and pagination */
.md-typeset .md-button {
  border-radius: 999px;
  padding-inline: 1rem;
  border-width: 1px;
}

.md-typeset .md-button--primary {
  background: linear-gradient(
    135deg,
    var(--ctb-brand-500),
    var(--ctb-brand-600)
  );
  border-color: var(--ctb-brand-600);
  color: #ffffff;
  box-shadow: var(--ctb-shadow-sm);
}

.md-footer {
  background: transparent;
}

.md-footer-meta {
  background: transparent;
}

.md-footer__inner {
  border-top: 1px solid var(--ctb-border-soft);
}

.md-footer__link {
  border: 1px solid var(--ctb-border-soft);
  border-radius: var(--ctb-radius-md);
  background: var(--ctb-bg-card);
}

.ctb-custom-footer {
  margin-top: 2rem;
  border-top: 1px solid var(--ctb-border-soft);
  background: var(--ctb-bg-page);
}

.ctb-custom-footer .md-footer-meta {
  background: transparent;
}

.ctb-custom-footer .md-footer-meta__inner {
  min-height: 0;
  padding: 1rem 0 1.1rem;
}

.ctb-custom-footer__content {
  display: flex;
  flex-wrap: wrap;
  gap: 0.5rem 1.1rem;
  justify-content: space-between;
  align-items: center;
  width: 100%;
  color: var(--ctb-text-muted);
  font-size: 0.74rem;
  line-height: 1.45;
}

.ctb-custom-footer__copyright,
.ctb-custom-footer__developer {
  margin: 0;
}

.ctb-custom-footer .ctb-custom-footer__developer a,
.ctb-custom-footer .ctb-custom-footer__developer a:visited {
  color: var(--ctb-brand-600);
  text-decoration: none;
  font-weight: 600;
}

[data-md-color-scheme="default"]
  .ctb-custom-footer
  .ctb-custom-footer__developer
  a,
[data-md-color-scheme="default"]
  .ctb-custom-footer
  .ctb-custom-footer__developer
  a:visited {
  color: var(--ctb-brand-700);
}

.ctb-custom-footer .ctb-custom-footer__developer a:hover,
.ctb-custom-footer .ctb-custom-footer__developer a:focus-visible {
  color: var(--ctb-brand-600);
  text-decoration: underline;
}

/* Images and figures */
.md-typeset img:not(.twemoji):not(.emoji):not(.gallery-image):not(.yt-thumb) {
  display: block;
  max-width: 100%;
  padding: 10px;
  margin: 1.25rem auto;
  border-radius: var(--ctb-radius-lg);
  border: 1px solid var(--ctb-border-soft);
  background: var(--ctb-bg-card);
  box-shadow: var(--ctb-shadow-md);
}

.md-typeset .youtube-gallery .yt-thumb,
.md-typeset .youtube-gallery a.glightbox > .yt-thumb {
  display: block;
  width: 100%;
  height: 100%;
  max-width: none;
  margin: 0;
  padding: 0;
  border: 0;
  border-radius: 0;
  background: transparent;
  box-shadow: none;
}

.md-typeset figure {
  margin: 1.25rem 0;
}

/* Selection and focus states for accessibility */
::selection {
  background: rgba(99, 102, 241, 0.28);
}

:where(a, button, summary, input, textarea, select):focus-visible {
  outline: 2px solid var(--ctb-brand-400);
  outline-offset: 2px;
}

/* Logo variants */
/* Logo variants */
[data-md-color-scheme="slate"] .md-header__button.md-logo img {
  content: url("../assets/images/ctb-logo.svg");
}

[data-md-color-scheme="default"] .md-header__button.md-logo img {
  content: url("../assets/images/ctb-logo-light.svg");
}

/* Shared offline shell styles for docs/offline.html */
body.offline-shell {
  min-height: 100%;
  margin: 0;
  padding: 24px;
  display: grid;
  place-items: center;
  font-family: var(--md-text-font-family, sans-serif);
}

html[data-theme="dark"] body.offline-shell {
  color: #e2e8f0;
  background:
    radial-gradient(circle at top, rgba(99, 102, 241, 0.2), transparent 34%),
    linear-gradient(180deg, #081226 0%, #0b1326 100%);
}

html[data-theme="light"] body.offline-shell {
  color: #1e293b;
  background:
    radial-gradient(circle at top, rgba(99, 102, 241, 0.12), transparent 34%),
    linear-gradient(180deg, #ffffff 0%, #f1f5f9 100%);
}

main.offline-shell__card {
  width: min(100%, 720px);
  padding: 32px;
  border-radius: 24px;
  -webkit-backdrop-filter: blur(14px);
  backdrop-filter: blur(14px);
}

html[data-theme="dark"] main.offline-shell__card {
  border: 1px solid rgba(148, 163, 184, 0.22);
  background: rgba(16, 27, 52, 0.84);
  box-shadow: 0 24px 80px rgba(2, 6, 23, 0.45);
}

html[data-theme="light"] main.offline-shell__card {
  border: 1px solid rgba(71, 85, 105, 0.26);
  background: rgba(255, 255, 255, 0.9);
  box-shadow: 0 20px 60px rgba(15, 23, 42, 0.12);
}

.offline-shell__eyebrow {
  margin: 0 0 12px;
  color: var(--ctb-brand-500);
  font-weight: 700;
  letter-spacing: 0.14em;
  text-transform: uppercase;
}

.offline-shell__title {
  margin: 0;
  font-size: clamp(2rem, 4vw, 3.35rem);
  line-height: 1.05;
}

.offline-shell__text {
  max-width: 60ch;
  margin: 16px 0 0;
  line-height: 1.7;
}

.offline-shell__actions {
  display: flex;
  flex-wrap: wrap;
  gap: 12px;
  margin-top: 28px;
}

.offline-shell__button,
.offline-shell__link {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  min-height: 44px;
  padding: 0 16px;
  border-radius: 999px;
  border: 1px solid transparent;
  font: inherit;
  text-decoration: none;
  cursor: pointer;
  transition:
    transform 160ms ease,
    border-color 160ms ease,
    background-color 160ms ease;
}

.offline-shell__button:hover,
.offline-shell__link:hover {
  transform: translateY(-1px);
}

.offline-shell__button {
  background: linear-gradient(
    135deg,
    var(--ctb-brand-400),
    var(--ctb-brand-600)
  );
  color: #ffffff;
  font-weight: 700;
}

html[data-theme="dark"] .offline-shell__link {
  background: transparent;
  border-color: rgba(148, 163, 184, 0.36);
  color: #e2e8f0;
}

html[data-theme="light"] .offline-shell__link {
  background: transparent;
  border-color: rgba(71, 85, 105, 0.3);
  color: #1e293b;
}

.offline-shell__status {
  margin-top: 20px;
  padding-top: 18px;
}

html[data-theme="dark"] .offline-shell__status {
  border-top: 1px solid rgba(148, 163, 184, 0.24);
  color: #94a3b8;
}

html[data-theme="light"] .offline-shell__status {
  border-top: 1px solid rgba(71, 85, 105, 0.2);
  color: #64748b;
}

/* Mobile refinements */
@media screen and (max-width: 76.1875em) {
  .md-sidebar--primary,
  .md-sidebar--secondary {
    border-right: none;
  }
}

@media screen and (max-width: 44.9375em) {
  .md-header__title {
    font-size: 0.9rem;
  }

  .md-typeset h1 {
    font-size: 1.65rem;
  }

  .main.offline-shell__card,
  main.offline-shell__card {
    padding: 22px;
  }

  body.offline-shell {
    padding: 12px;
  }
}