/* ============================================================================
   storagebackend.org — Apache JanusGraph Storage Backend & Index Synchronization
   Light, professional theme. Mobile-first, comfortable wide measure on desktop.
   ========================================================================== */

/* ---- Design tokens ------------------------------------------------------- */
:root {
  /* Palette — easy-on-the-eyes light scheme */
  --teal-50: #ecfeff;
  --teal-100: #cffafe;
  --teal-500: #06b6d4;
  --teal-600: #0e7490;
  --teal-700: #155e75;
  --violet-600: #7c3aed;
  --amber-600: #c2410c;

  --bg: #f7fafc;
  --bg-soft: #eef3f7;
  --surface: #ffffff;
  --surface-2: #f4f8fb;
  --border: #dde6ec;
  --border-strong: #c4d2dc;

  --text: #1b2a33;
  --text-muted: #51616b;
  --heading: #0f2730;

  --accent: var(--teal-600);
  --link: #0e7490;
  --link-hover: #0a5566;

  --code-bg: #f3f7f9;
  --code-inline-bg: #eaf2f5;
  --code-text: #1f3540;

  --radius: 12px;
  --radius-sm: 8px;
  --radius-lg: 18px;
  --shadow-sm: 0 1px 2px rgba(15, 39, 48, 0.06), 0 1px 3px rgba(15, 39, 48, 0.08);
  --shadow-md: 0 4px 12px rgba(15, 39, 48, 0.08), 0 2px 4px rgba(15, 39, 48, 0.06);
  --shadow-lg: 0 18px 40px rgba(15, 39, 48, 0.12);

  --header-h: 64px;
  --measure: 78ch;
  --container: 1280px;
  --container-wide: 1440px;

  --font-sans: "Inter", -apple-system, BlinkMacSystemFont, "Segoe UI", Roboto,
    Helvetica, Arial, sans-serif;
  --font-mono: "SFMono-Regular", "JetBrains Mono", "Fira Code", Consolas,
    "Liberation Mono", Menlo, monospace;

  --transition: 160ms cubic-bezier(0.4, 0, 0.2, 1);
}

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

html {
  scroll-behavior: smooth;
  -webkit-text-size-adjust: 100%;
}

body {
  margin: 0;
  font-family: var(--font-sans);
  font-size: 1.0625rem;
  line-height: 1.7;
  color: var(--text);
  background: var(--bg);
  /* sticky footer */
  display: flex;
  flex-direction: column;
  min-height: 100vh;
  min-height: 100dvh;
  -webkit-font-smoothing: antialiased;
  text-rendering: optimizeLegibility;
}

.site-main {
  flex: 1 0 auto;
}

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

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

:focus-visible {
  outline: 3px solid var(--teal-500);
  outline-offset: 2px;
  border-radius: 3px;
}

.container {
  width: 100%;
  max-width: var(--container-wide);
  margin-inline: auto;
  padding-inline: clamp(1rem, 4vw, 3rem);
}

.sr-only {
  position: absolute;
  width: 1px;
  height: 1px;
  padding: 0;
  margin: -1px;
  overflow: hidden;
  clip: rect(0, 0, 0, 0);
  white-space: nowrap;
  border: 0;
}

.skip-link {
  position: absolute;
  left: -999px;
  top: 0;
  z-index: 200;
  background: var(--teal-600);
  color: #fff;
  padding: 0.6rem 1rem;
  border-radius: 0 0 var(--radius-sm) 0;
}
.skip-link:focus {
  left: 0;
}

/* ---- Icons --------------------------------------------------------------- */
.icon {
  width: 1.5em;
  height: 1.5em;
  flex: none;
  vertical-align: middle;
}
.icon--sm {
  width: 1em;
  height: 1em;
}

/* ============================================================================
   Header
   ========================================================================== */
.site-header {
  position: sticky;
  top: 0;
  z-index: 100;
  background: rgba(255, 255, 255, 0.85);
  backdrop-filter: saturate(180%) blur(12px);
  border-bottom: 1px solid var(--border);
  box-shadow: var(--shadow-sm);
}
.site-header__inner {
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 1rem;
  min-height: var(--header-h);
  max-width: var(--container-wide);
}

.brand {
  display: inline-flex;
  align-items: center;
  gap: 0.65rem;
  color: var(--heading);
  font-weight: 700;
}
.brand__logo {
  transition: transform var(--transition);
}
.brand:hover .brand__logo {
  transform: rotate(-8deg) scale(1.06);
}
.brand__text {
  display: flex;
  flex-direction: column;
  line-height: 1.15;
}
.brand__name {
  font-size: 1.15rem;
  letter-spacing: -0.01em;
  background: linear-gradient(90deg, var(--teal-600), var(--violet-600));
  -webkit-background-clip: text;
  background-clip: text;
  color: transparent;
}
.brand__sub {
  font-size: 0.72rem;
  font-weight: 600;
  color: var(--text-muted);
  text-transform: uppercase;
  letter-spacing: 0.04em;
}

.primary-nav__list {
  display: flex;
  align-items: center;
  gap: 0.35rem;
  list-style: none;
  margin: 0;
  padding: 0;
}
.primary-nav__link {
  display: inline-flex;
  align-items: center;
  gap: 0.45rem;
  padding: 0.5rem 0.85rem;
  border-radius: var(--radius-sm);
  font-weight: 600;
  font-size: 0.95rem;
  color: var(--text-muted);
  position: relative;
}
.primary-nav__link .icon {
  width: 1.2em;
  height: 1.2em;
  color: var(--accent, var(--teal-600));
}
.primary-nav__link:hover {
  color: var(--heading);
  background: var(--surface-2);
}
.primary-nav__link.is-active {
  color: var(--heading);
  background: color-mix(in srgb, var(--accent, var(--teal-600)) 12%, transparent);
}
.primary-nav__link.is-active::after {
  content: "";
  position: absolute;
  left: 0.85rem;
  right: 0.85rem;
  bottom: -2px;
  height: 3px;
  border-radius: 3px 3px 0 0;
  background: var(--accent, var(--teal-600));
}

.nav-toggle {
  display: none;
  align-items: center;
  justify-content: center;
  width: 44px;
  height: 44px;
  border: 1px solid var(--border);
  background: var(--surface);
  border-radius: var(--radius-sm);
  color: var(--heading);
  cursor: pointer;
}
.nav-toggle__close {
  display: none;
}
.nav-toggle[aria-expanded="true"] .nav-toggle__open {
  display: none;
}
.nav-toggle[aria-expanded="true"] .nav-toggle__close {
  display: inline;
}

@media (max-width: 820px) {
  .nav-toggle {
    display: inline-flex;
  }
  .primary-nav {
    position: fixed;
    inset: var(--header-h) 0 auto 0;
    background: var(--surface);
    border-bottom: 1px solid var(--border);
    box-shadow: var(--shadow-lg);
    padding: 0.75rem clamp(1rem, 4vw, 3rem) 1.25rem;
    transform: translateY(-130%);
    transition: transform var(--transition);
    visibility: hidden;
  }
  .primary-nav.is-open {
    transform: translateY(0);
    visibility: visible;
  }
  .primary-nav__list {
    flex-direction: column;
    align-items: stretch;
    gap: 0.25rem;
  }
  .primary-nav__link {
    padding: 0.8rem 1rem;
    font-size: 1.05rem;
  }
  .primary-nav__link.is-active::after {
    display: none;
  }
  .primary-nav__link .icon {
    width: 1.4em;
    height: 1.4em;
  }
}

/* ============================================================================
   Hero / home
   ========================================================================== */
.hero {
  background:
    radial-gradient(1200px 480px at 50% -10%, var(--teal-50), transparent 60%),
    radial-gradient(900px 420px at 85% 0%, #f5f0ff, transparent 55%),
    var(--bg);
  border-bottom: 1px solid var(--border);
}
.hero__inner {
  text-align: center;
  padding-block: clamp(2.5rem, 6vw, 4.5rem);
  max-width: var(--container-wide);
}
.hero__logo-row {
  margin-bottom: 1.25rem;
}
.hero__logo {
  filter: drop-shadow(0 10px 24px rgba(14, 116, 144, 0.25));
  animation: float 6s ease-in-out infinite;
}
@keyframes float {
  0%, 100% { transform: translateY(0); }
  50% { transform: translateY(-8px); }
}
.hero__title {
  font-size: clamp(1.9rem, 5vw, 3.25rem);
  line-height: 1.1;
  letter-spacing: -0.02em;
  margin: 0 auto 1rem;
  color: var(--heading);
  max-width: 18ch;
}
.hero__title-accent {
  background: linear-gradient(90deg, var(--teal-600), var(--violet-600) 60%, var(--amber-600));
  -webkit-background-clip: text;
  background-clip: text;
  color: transparent;
}
.hero__lede {
  font-size: clamp(1.05rem, 2.2vw, 1.3rem);
  color: var(--text-muted);
  max-width: 60ch;
  margin: 0 auto 2rem;
}
.hero__cta {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(280px, 1fr));
  gap: 1.25rem;
  /* Span the full hero width so the top of the page uses the same width as the
     section cards below. */
  width: 100%;
  margin-inline: auto;
}
.cta-btn {
  display: flex;
  align-items: center;
  gap: 0.9rem;
  text-align: left;
  padding: 1rem 1.15rem;
  background: var(--surface);
  border: 1px solid var(--border);
  border-radius: var(--radius);
  box-shadow: var(--shadow-sm);
  transition: transform var(--transition), box-shadow var(--transition),
    border-color var(--transition);
}
.cta-btn:hover {
  transform: translateY(-3px);
  box-shadow: var(--shadow-md);
  border-color: color-mix(in srgb, var(--accent) 45%, var(--border));
}
.cta-btn__icon {
  display: grid;
  place-items: center;
  width: 48px;
  height: 48px;
  flex: none;
  border-radius: 12px;
  color: #fff;
  background: linear-gradient(135deg,
    color-mix(in srgb, var(--accent) 85%, white),
    var(--accent));
}
.cta-btn__icon .icon {
  width: 1.6em;
  height: 1.6em;
}
.cta-btn__text {
  display: flex;
  flex-direction: column;
  flex: 1;
}
.cta-btn__label {
  font-weight: 700;
  color: var(--heading);
}
.cta-btn__sub {
  font-size: 0.85rem;
  color: var(--text-muted);
}
.cta-btn__go {
  color: var(--accent);
  transition: transform var(--transition);
}
.cta-btn:hover .cta-btn__go {
  transform: translateX(4px);
}

/* Intro */
.intro {
  padding-block: clamp(2rem, 5vw, 3.5rem);
}
/* `.prose.intro__prose` (specificity 0,2,0) so this wins over the later
   `.prose { max-width: 92ch }` desktop rule and actually fills the container. */
.prose.intro__prose {
  /* Flow the intro paragraphs into a full-width row that mirrors the section
     cards below, instead of a single narrow centred column. */
  max-width: none;
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(300px, 1fr));
  gap: 2rem;
}
.intro__prose > * + * {
  margin-top: 0;
}

/* Section cards */
.sections {
  padding-bottom: clamp(2.5rem, 6vw, 4rem);
}
.section-heading {
  text-align: center;
  font-size: clamp(1.5rem, 3vw, 2rem);
  color: var(--heading);
  margin-bottom: 2rem;
}
.sections__grid {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(300px, 1fr));
  gap: 1.5rem;
}
.section-card {
  display: flex;
  flex-direction: column;
  background: var(--surface);
  border: 1px solid var(--border);
  border-top: 4px solid var(--accent);
  border-radius: var(--radius-lg);
  padding: 1.5rem;
  box-shadow: var(--shadow-sm);
  transition: transform var(--transition), box-shadow var(--transition);
}
.section-card:hover {
  transform: translateY(-4px);
  box-shadow: var(--shadow-lg);
}
.section-card__head {
  display: flex;
  align-items: center;
  gap: 0.75rem;
  margin-bottom: 0.75rem;
}
.section-card__icon {
  display: grid;
  place-items: center;
  width: 44px;
  height: 44px;
  flex: none;
  border-radius: 12px;
  color: var(--accent);
  background: color-mix(in srgb, var(--accent) 12%, white);
}
.section-card__title {
  margin: 0;
  font-size: 1.2rem;
  line-height: 1.25;
}
.section-card__title a {
  color: var(--heading);
}
.section-card__title a:hover {
  color: var(--accent);
}
.section-card__blurb {
  color: var(--text-muted);
  font-size: 0.96rem;
  margin: 0 0 1rem;
}
.section-card__links {
  list-style: none;
  margin: 0 0 1rem;
  padding: 0;
  display: flex;
  flex-direction: column;
  gap: 0.15rem;
}
.section-card__links a {
  display: flex;
  align-items: center;
  gap: 0.4rem;
  padding: 0.3rem 0.4rem;
  border-radius: var(--radius-sm);
  color: var(--text);
  font-size: 0.93rem;
}
.section-card__links a:hover {
  background: var(--surface-2);
  color: var(--accent);
}
.section-card__links .icon {
  color: var(--accent);
}
.section-card__more {
  margin-top: auto;
  display: inline-flex;
  align-items: center;
  gap: 0.35rem;
  font-weight: 600;
  color: var(--accent);
}
.section-card__more .icon {
  transition: transform var(--transition);
}
.section-card__more:hover .icon {
  transform: translateX(4px);
}

/* ============================================================================
   Doc page layout
   ========================================================================== */
.doc-shell {
  max-width: var(--container-wide);
  padding-block: 2rem 3rem;
}

.breadcrumbs {
  margin-bottom: 1.5rem;
  font-size: 0.9rem;
}
.breadcrumbs__list {
  display: flex;
  flex-wrap: wrap;
  align-items: center;
  gap: 0.3rem;
  list-style: none;
  margin: 0;
  padding: 0;
  color: var(--text-muted);
}
.breadcrumbs__item {
  display: inline-flex;
  align-items: center;
  gap: 0.3rem;
}
.breadcrumbs__sep {
  color: var(--border-strong);
}
.breadcrumbs a {
  color: var(--text-muted);
}
.breadcrumbs a:hover {
  color: var(--accent);
}
.breadcrumbs [aria-current="page"] {
  color: var(--heading);
  font-weight: 600;
}

/* ============================================================================
   Prose / typography
   ========================================================================== */
.prose {
  /* General prose (e.g. the home intro) keeps a comfortable centred measure. */
  max-width: var(--measure);
}
@media (min-width: 1100px) {
  .prose {
    max-width: 92ch;
  }
}
/* Article body fills the full width of its container (= the header width),
   never a narrow column. */
.doc.prose {
  max-width: none;
}

.prose > * + * {
  margin-top: 1.1em;
}

.prose h1 {
  font-size: clamp(1.9rem, 4vw, 2.6rem);
  line-height: 1.15;
  letter-spacing: -0.02em;
  margin: 0 0 0.6em;
  background: linear-gradient(90deg, var(--teal-700), var(--violet-600));
  -webkit-background-clip: text;
  background-clip: text;
  color: transparent;
}
.prose h2 {
  font-size: clamp(1.4rem, 2.6vw, 1.8rem);
  line-height: 1.25;
  margin-top: 2em;
  padding-bottom: 0.3em;
  color: var(--heading);
  border-bottom: 2px solid var(--border);
}
.prose h3 {
  font-size: 1.3rem;
  margin-top: 1.6em;
  color: var(--teal-700);
}
.prose h4 {
  font-size: 1.1rem;
  margin-top: 1.4em;
  color: var(--heading);
}
/* Sticky-header offset for in-page anchors */
.prose :is(h1, h2, h3, h4, h5, h6)[id] {
  scroll-margin-top: calc(var(--header-h) + 1rem);
}
.prose :is(h2, h3, h4) a.header-anchor {
  color: inherit;
}
.prose :is(h2, h3, h4) a.header-anchor:hover {
  color: var(--accent);
}

.prose p {
  color: var(--text);
}
.prose strong {
  color: var(--heading);
  font-weight: 700;
}

.prose a:not(.header-anchor) {
  color: var(--link);
  font-weight: 500;
  text-decoration: underline;
  text-decoration-color: color-mix(in srgb, var(--link) 35%, transparent);
  text-underline-offset: 2px;
  transition: color var(--transition), text-decoration-color var(--transition);
}
.prose a:not(.header-anchor):hover {
  color: var(--link-hover);
  text-decoration-color: var(--link-hover);
}

.prose ul,
.prose ol {
  margin-block: 1.1em;
  padding-left: 0;
  list-style: none;
}
.prose li {
  position: relative;
}
.prose li + li {
  margin-top: 0.55em;
}

/* Unordered lists — gradient diamond bullets (task lists excluded). */
.prose ul:not(.task-list) > li {
  padding-left: 1.7em;
}
.prose ul:not(.task-list) > li::before {
  content: "";
  position: absolute;
  left: 0.3em;
  top: 0.62em;
  width: 0.55em;
  height: 0.55em;
  border-radius: 2px;
  background: linear-gradient(135deg, var(--teal-500), var(--violet-600));
  transform: rotate(45deg);
  transition: transform var(--transition);
}
.prose ul:not(.task-list) > li:hover::before {
  transform: rotate(45deg) scale(1.25);
}
/* Nested unordered lists use a lighter, hollow marker. */
.prose ul:not(.task-list) ul > li::before {
  background: none;
  border: 2px solid var(--teal-500);
}

/* Ordered lists — numbered gradient badges. */
.prose ol {
  counter-reset: prose-ol;
}
.prose ol > li {
  padding-left: 2.4em;
  counter-increment: prose-ol;
}
.prose ol > li::before {
  content: counter(prose-ol);
  position: absolute;
  left: 0;
  top: 0.1em;
  display: grid;
  place-items: center;
  min-width: 1.7em;
  height: 1.7em;
  padding: 0 0.35em;
  font-size: 0.82em;
  font-weight: 700;
  line-height: 1;
  color: #fff;
  background: linear-gradient(135deg, var(--teal-600), var(--teal-700));
  border-radius: 999px;
  box-shadow: var(--shadow-sm);
}
/* Nested ordered lists fall back to lighter badges. */
.prose ol ol > li::before {
  background: linear-gradient(135deg, var(--violet-600), #5b21b6);
}

.prose li > ul,
.prose li > ol {
  margin-block: 0.55em;
}

.prose blockquote {
  margin: 1.5em 0;
  padding: 0.5em 1.2em;
  border-left: 4px solid var(--teal-500);
  background: var(--teal-50);
  border-radius: 0 var(--radius-sm) var(--radius-sm) 0;
  color: var(--text-muted);
}

.prose hr {
  border: none;
  border-top: 1px solid var(--border);
  margin: 2.5em 0;
}

/* ---- Inline code --------------------------------------------------------- */
.prose :not(pre) > code {
  font-family: var(--font-mono);
  font-size: 0.88em;
  background: var(--code-inline-bg);
  color: var(--code-text);
  padding: 0.12em 0.4em;
  border-radius: 5px;
  border: none;
  white-space: break-spaces;
}

/* ---- Code blocks --------------------------------------------------------- */
.code-block {
  margin: 1.5em 0;
  background: var(--code-bg);
  border: 1px solid var(--border);
  border-radius: var(--radius);
  overflow: hidden;
  box-shadow: var(--shadow-sm);
}
.code-block__bar {
  display: flex;
  align-items: center;
  justify-content: space-between;
  padding: 0.4rem 0.5rem 0.4rem 0.9rem;
  background: var(--surface-2);
  border-bottom: 1px solid var(--border);
}
.code-block__lang {
  font-family: var(--font-mono);
  font-size: 0.72rem;
  font-weight: 600;
  letter-spacing: 0.06em;
  text-transform: uppercase;
  color: var(--text-muted);
}
.code-block__copy {
  display: inline-flex;
  align-items: center;
  gap: 0.35rem;
  padding: 0.3rem 0.6rem;
  font-size: 0.78rem;
  font-weight: 600;
  color: var(--teal-700);
  background: var(--surface);
  border: 1px solid var(--border);
  border-radius: var(--radius-sm);
  cursor: pointer;
  transition: all var(--transition);
}
.code-block__copy:hover {
  background: var(--teal-600);
  border-color: var(--teal-600);
  color: #fff;
}
.code-block__copy.is-copied {
  background: #0f9d58;
  border-color: #0f9d58;
  color: #fff;
}
.code-block__icon {
  width: 14px;
  height: 14px;
}
.code-block pre {
  margin: 0;
  padding: 1.1rem 1.2rem;
  overflow-x: auto;
  font-family: var(--font-mono);
  font-size: 0.88rem;
  line-height: 1.6;
  color: var(--code-text);
  background: var(--code-bg);
  -webkit-overflow-scrolling: touch;
}
.code-block code {
  font-family: inherit;
  background: none;
  padding: 0;
  border: none;
  white-space: pre;
}

/* ---- Prism light-theme token colours (match site palette) ---------------- */
.token.comment,
.token.prolog,
.token.doctype,
.token.cdata {
  color: #6b7b85;
  font-style: italic;
}
.token.punctuation {
  color: #51616b;
}
.token.property,
.token.tag,
.token.boolean,
.token.number,
.token.constant,
.token.symbol {
  color: #b25000;
}
.token.selector,
.token.attr-name,
.token.string,
.token.char,
.token.builtin {
  color: #0a7d57;
}
.token.operator,
.token.entity,
.token.url {
  color: #155e75;
}
.token.atrule,
.token.attr-value,
.token.keyword {
  color: #7c3aed;
  font-weight: 600;
}
.token.function,
.token.class-name {
  color: #0e7490;
  font-weight: 600;
}
.token.regex,
.token.important,
.token.variable {
  color: #b25000;
}

/* ---- Tables -------------------------------------------------------------- */
.table-wrap {
  margin: 1.5em 0;
  overflow-x: auto;
  border: 1px solid var(--border);
  border-radius: var(--radius);
  box-shadow: var(--shadow-sm);
  -webkit-overflow-scrolling: touch;
}
.table-wrap table {
  width: 100%;
  border-collapse: collapse;
  font-size: 0.95rem;
}
.table-wrap th,
.table-wrap td {
  padding: 0.7rem 1rem;
  text-align: left;
  border-bottom: 1px solid var(--border);
}
.table-wrap thead th {
  background: var(--surface-2);
  color: var(--heading);
  font-weight: 700;
  white-space: nowrap;
}
.table-wrap tbody tr:nth-child(even) {
  background: var(--surface-2);
}
.table-wrap tbody tr:hover {
  background: var(--teal-50);
}

/* ---- Task lists ---------------------------------------------------------- */
.task-list {
  list-style: none;
  padding-left: 0.2em;
}
.task-list__item {
  list-style: none;
}
.task-list__item::marker {
  content: "";
}
.task-list__checkbox {
  appearance: none;
  -webkit-appearance: none;
  width: 1.15em;
  height: 1.15em;
  margin-right: 0.55em;
  vertical-align: -0.18em;
  border: 2px solid var(--border-strong);
  border-radius: 5px;
  background: var(--surface);
  cursor: pointer;
  position: relative;
  transition: all var(--transition);
}
.task-list__checkbox:hover {
  border-color: var(--teal-600);
}
.task-list__checkbox:checked {
  background: var(--teal-600);
  border-color: var(--teal-600);
}
.task-list__checkbox:checked::after {
  content: "";
  position: absolute;
  left: 4px;
  top: 1px;
  width: 4px;
  height: 8px;
  border: solid #fff;
  border-width: 0 2px 2px 0;
  transform: rotate(45deg);
}
.task-list__item:has(.task-list__checkbox:checked) {
  text-decoration: line-through;
  color: var(--text-muted);
}

/* ---- FAQ accordions ------------------------------------------------------ */
.faq {
  border: 1px solid var(--border);
  border-radius: var(--radius);
  overflow: hidden;
  margin: 1em 0;
  background: var(--surface);
}
.faq + .faq {
  margin-top: 0.6em;
}
.faq > summary {
  cursor: pointer;
  list-style: none;
  padding: 0.95rem 1.2rem;
  font-weight: 600;
  color: var(--heading);
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 1rem;
  background: var(--surface-2);
  transition: background var(--transition);
}
.faq > summary::-webkit-details-marker {
  display: none;
}
.faq > summary::after {
  content: "+";
  font-size: 1.4rem;
  font-weight: 400;
  color: var(--teal-600);
  transition: transform var(--transition);
}
.faq[open] > summary::after {
  transform: rotate(45deg);
}
.faq > summary:hover {
  background: var(--teal-50);
}
.faq__body {
  padding: 0.4rem 1.2rem 1.1rem;
}

/* ---- Mermaid ------------------------------------------------------------- */
.mermaid-wrap {
  position: relative;
  margin: 1.5em 0;
  padding: 1.25rem 1rem 1.5rem;
  background:
    radial-gradient(120% 100% at 50% 0%, var(--teal-50), transparent 70%),
    var(--surface);
  border: 1px solid var(--border);
  border-radius: var(--radius);
  overflow-x: auto;
  text-align: center;
  box-shadow: var(--shadow-sm);
}
.mermaid {
  background: none;
}
/* Make rendered diagrams responsive */
.mermaid-wrap svg {
  max-width: 100%;
  height: auto;
}
/* Caption (optional, from the diagram's data-caption) */
.mermaid-wrap__caption {
  display: block;
  margin-top: 0.75rem;
  font-size: 0.85rem;
  color: var(--text-muted);
  font-style: italic;
}

/* Click-to-enlarge affordance ------------------------------------------------ */
.mermaid-wrap.is-ready {
  cursor: zoom-in;
}
.mermaid-wrap__expand {
  position: absolute;
  top: 0.6rem;
  right: 0.6rem;
  display: inline-flex;
  align-items: center;
  gap: 0.35rem;
  padding: 0.35rem 0.6rem;
  font-size: 0.75rem;
  font-weight: 600;
  color: var(--teal-700);
  background: rgba(255, 255, 255, 0.9);
  border: 1px solid var(--border);
  border-radius: var(--radius-sm);
  cursor: zoom-in;
  opacity: 0;
  transform: translateY(-4px);
  transition: opacity var(--transition), transform var(--transition),
    background var(--transition), color var(--transition);
}
.mermaid-wrap:hover .mermaid-wrap__expand,
.mermaid-wrap:focus-within .mermaid-wrap__expand {
  opacity: 1;
  transform: translateY(0);
}
.mermaid-wrap__expand:hover {
  background: var(--teal-600);
  border-color: var(--teal-600);
  color: #fff;
}
.mermaid-wrap__expand .icon {
  width: 1em;
  height: 1em;
}

/* Fullscreen diagram modal --------------------------------------------------- */
.diagram-modal {
  position: fixed;
  inset: 0;
  z-index: 1000;
  display: flex;
  flex-direction: column;
  background: rgba(8, 24, 30, 0.82);
  backdrop-filter: blur(4px);
  opacity: 0;
  visibility: hidden;
  transition: opacity var(--transition), visibility var(--transition);
}
.diagram-modal.is-open {
  opacity: 1;
  visibility: visible;
}
.diagram-modal__bar {
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 1rem;
  padding: 0.75rem 1.25rem;
  color: #e6f2f6;
}
.diagram-modal__title {
  font-size: 0.95rem;
  font-weight: 600;
  margin: 0;
  overflow: hidden;
  text-overflow: ellipsis;
  white-space: nowrap;
}
.diagram-modal__close {
  display: inline-flex;
  align-items: center;
  gap: 0.4rem;
  flex: none;
  padding: 0.5rem 0.9rem;
  font-size: 0.9rem;
  font-weight: 600;
  color: #0f2730;
  background: #fff;
  border: none;
  border-radius: var(--radius-sm);
  cursor: pointer;
  transition: background var(--transition), transform var(--transition);
}
.diagram-modal__close:hover {
  background: var(--teal-100);
  transform: translateY(-1px);
}
.diagram-modal__stage {
  flex: 1;
  display: flex;
  align-items: center;
  justify-content: center;
  padding: 0 1.5rem 1.75rem;
  overflow: auto;
}
.diagram-modal__stage svg {
  width: auto;
  height: auto;
  max-width: 96vw;
  max-height: 82vh;
  background: #fff;
  border-radius: var(--radius);
  padding: 1.5rem;
  box-shadow: var(--shadow-lg);
}
body.modal-open {
  overflow: hidden;
}

/* ---- KaTeX --------------------------------------------------------------- */
.katex-display {
  overflow-x: auto;
  overflow-y: hidden;
  padding: 0.5em 0;
}

/* ============================================================================
   Related navigation (doc footer)
   ========================================================================== */
.related {
  margin-top: 3rem;
  padding-top: 1.5rem;
  border-top: 1px solid var(--border);
}
.related__title {
  display: flex;
  align-items: center;
  gap: 0.5rem;
  font-size: 1.2rem;
  color: var(--heading);
  margin: 0 0 1rem;
}
.related__title .icon {
  color: var(--teal-600);
}
.related__grid {
  list-style: none;
  margin: 0;
  padding: 0;
  display: grid;
  grid-template-columns: repeat(auto-fill, minmax(260px, 1fr));
  gap: 0.75rem;
}
.related__card a {
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 0.75rem;
  padding: 0.9rem 1.1rem;
  background: var(--surface);
  border: 1px solid var(--border);
  border-radius: var(--radius);
  color: var(--heading);
  font-weight: 600;
  box-shadow: var(--shadow-sm);
  transition: transform var(--transition), box-shadow var(--transition),
    border-color var(--transition);
}
.related__card a:hover {
  transform: translateY(-2px);
  box-shadow: var(--shadow-md);
  border-color: var(--teal-500);
  color: var(--teal-700);
}
.related__card-go {
  color: var(--teal-600);
  transition: transform var(--transition);
}
.related__card a:hover .related__card-go {
  transform: translateX(4px);
}
.related__links {
  list-style: none;
  margin: 0;
  padding: 0;
  display: grid;
  grid-template-columns: repeat(auto-fill, minmax(280px, 1fr));
  gap: 0.3rem;
}
.related__links a {
  display: flex;
  align-items: center;
  gap: 0.45rem;
  padding: 0.5rem 0.6rem;
  border-radius: var(--radius-sm);
  color: var(--text);
}
.related__links a:hover {
  background: var(--surface-2);
  color: var(--teal-700);
}
.related__links .icon {
  color: var(--teal-600);
}

/* ============================================================================
   Footer
   ========================================================================== */
.site-footer {
  flex-shrink: 0;
  margin-top: 4rem;
  background: var(--heading);
  color: #c7d6dd;
}
.site-footer__inner {
  display: grid;
  grid-template-columns: 1.2fr 1fr;
  gap: 2rem;
  padding-block: 2.5rem;
  max-width: var(--container-wide);
}
.site-footer__brand {
  display: flex;
  gap: 1rem;
  align-items: flex-start;
}
.site-footer__logo {
  background: #fff;
  border-radius: 10px;
  padding: 4px;
}
.site-footer__tagline {
  margin: 0;
  max-width: 42ch;
  font-size: 0.95rem;
  color: #9fb3bd;
}
.site-footer__heading {
  font-size: 0.8rem;
  text-transform: uppercase;
  letter-spacing: 0.08em;
  color: #7f97a2;
  margin: 0 0 0.75rem;
}
.site-footer__nav ul {
  list-style: none;
  margin: 0;
  padding: 0;
  display: flex;
  flex-direction: column;
  gap: 0.4rem;
}
.site-footer__nav a {
  display: inline-flex;
  align-items: center;
  gap: 0.5rem;
  color: #c7d6dd;
  font-weight: 500;
}
.site-footer__nav a:hover {
  color: #fff;
}
.site-footer__nav .icon {
  color: color-mix(in srgb, var(--accent, var(--teal-500)) 80%, white);
}
.site-footer__bar {
  border-top: 1px solid rgba(255, 255, 255, 0.1);
  padding-block: 1rem;
  max-width: var(--container-wide);
}
.site-footer__bar p {
  margin: 0;
  font-size: 0.85rem;
  color: #7f97a2;
}

@media (max-width: 640px) {
  .site-footer__inner {
    grid-template-columns: 1fr;
    gap: 1.5rem;
  }
}

/* ============================================================================
   Status pages (offline / 404)
   ========================================================================== */
.status {
  display: grid;
  place-items: center;
  text-align: center;
  padding-block: clamp(3rem, 10vw, 6rem);
}
.status__inner {
  max-width: 560px;
}
.status__logo {
  margin-bottom: 1rem;
}
.status__code {
  font-size: clamp(3rem, 12vw, 5.5rem);
  font-weight: 800;
  line-height: 1;
  margin: 0;
  background: linear-gradient(90deg, var(--teal-600), var(--violet-600));
  -webkit-background-clip: text;
  background-clip: text;
  color: transparent;
}
.status__title {
  font-size: clamp(1.6rem, 4vw, 2.2rem);
  color: var(--heading);
  margin: 0.25rem 0 0.75rem;
}
.status__text {
  color: var(--text-muted);
  margin: 0 auto 1.75rem;
}
.status__cta {
  display: inline-flex;
  max-width: 280px;
  margin-inline: auto;
}
.status__links {
  display: grid;
  gap: 0.75rem;
  max-width: 360px;
  margin-inline: auto;
}

/* ---- Motion preferences -------------------------------------------------- */
@media (prefers-reduced-motion: reduce) {
  *,
  *::before,
  *::after {
    animation-duration: 0.01ms !important;
    animation-iteration-count: 1 !important;
    transition-duration: 0.01ms !important;
    scroll-behavior: auto !important;
  }
}