/* ---------- Buttons ---------- */
.btn {
  display: inline-flex;
  align-items: center;
  gap: 0.55rem;
  padding: 0.7rem 1.1rem;
  border-radius: var(--radius-md);
  font-weight: 600;
  font-size: 0.95rem;
  text-decoration: none;
  border: 1px solid transparent;
  transition: transform var(--dur-fast) var(--ease),
              box-shadow var(--dur-base) var(--ease),
              background var(--dur-base) var(--ease),
              color var(--dur-base) var(--ease);
  will-change: transform;
}
.btn:hover { transform: translateY(-2px); box-shadow: var(--shadow-md); }
.btn--primary {
  background: linear-gradient(180deg, var(--c-primary), var(--c-primary-700));
  color: #fff;
}
.btn--primary:hover { color: #fff; }
.btn--ghost {
  background: var(--c-surface);
  color: var(--c-primary-700);
  border-color: var(--c-border);
}
.btn--ghost:hover { color: var(--c-primary); border-color: var(--c-accent-300); }

/* ---------- Breadcrumbs ---------- */
.crumbs {
  list-style: none;
  padding: 0;
  margin: 1.25rem 0 0.75rem;
  display: flex;
  flex-wrap: wrap;
  gap: 0.25rem 0.4rem;
  font-size: 0.86rem;
  color: var(--c-text-soft);
}
.crumbs li { display: inline-flex; align-items: center; gap: 0.4rem; margin: 0; }
.crumbs li + li::before {
  content: "›";
  color: var(--c-border);
  font-weight: 700;
}
.crumbs a {
  color: var(--c-text-muted);
  text-decoration: none;
  border-bottom: 1px solid transparent;
}
.crumbs a:hover { color: var(--c-primary); border-bottom-color: var(--c-accent-300); }
.crumbs [aria-current="page"] { color: var(--c-primary-700); font-weight: 600; }

/* ---------- Hero (frontpage) ---------- */
.hero {
  padding: clamp(2rem, 3vw, 4rem) 0 1.5rem;
  text-align: center;
}
.hero__logo {
  width: clamp(180px, 24vw, 320px);
  height: auto;
  margin: 0 auto 1.8rem;
  filter: drop-shadow(0 18px 36px rgba(31,79,122,0.24));
  transition: transform var(--dur-slow) var(--ease);
}
.hero__logo:hover { transform: translateY(-4px) rotate(-1.5deg); }
.hero__title {
  font-size: clamp(1.6rem, 1.05rem + 2.4vw, var(--fs-4xl));
  margin: 0 0 1rem;
  line-height: 1.12;
  background: linear-gradient(90deg, var(--c-primary-700), var(--c-accent));
  -webkit-background-clip: text;
  background-clip: text;
  color: transparent;
  overflow-wrap: break-word;
  hyphens: auto;
  max-width: 100%;
  padding-inline: 0.25rem;
}
.hero__lead {
  font-size: clamp(1.05rem, 1rem + 0.35vw, 1.22rem);
  color: var(--c-text-muted);
  max-width: 78ch;
  margin: 0 auto 0.9rem;
  line-height: 1.55;
}
.hero__cta {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(240px, 1fr));
  gap: 1rem;
  max-width: 980px;
  margin: 2rem auto 0;
}
.cta-card {
  display: flex;
  flex-direction: column;
  align-items: flex-start;
  gap: 0.6rem;
  text-align: left;
  padding: 1.1rem 1.2rem;
  background: var(--c-surface);
  border: 1px solid var(--c-border);
  border-radius: var(--radius-lg);
  color: var(--c-text);
  text-decoration: none;
  box-shadow: var(--shadow-sm);
  transition: transform var(--dur-base) var(--ease),
              box-shadow var(--dur-base) var(--ease),
              border-color var(--dur-base) var(--ease);
}
.cta-card:hover {
  transform: translateY(-4px);
  box-shadow: var(--shadow-lg);
  border-color: var(--c-accent-300);
  color: var(--c-text);
}
.cta-card__icon {
  width: 46px;
  height: 46px;
  display: inline-flex;
  align-items: center;
  justify-content: center;
  border-radius: 12px;
}
.cta-card__icon svg { width: 28px; height: 28px; }
.cta-card--gear  .cta-card__icon { background: linear-gradient(135deg, #e7f1fb, #d7e4f3); color: #1f4f7a; }
.cta-card--funnel .cta-card__icon { background: linear-gradient(135deg, #e2f6f0, #cdebde); color: #2f8c5b; }
.cta-card--gauge .cta-card__icon { background: linear-gradient(135deg, #fff1d6, #ffe1b8); color: #c18306; }

.cta-card__title {
  margin: 0;
  font-family: var(--font-display);
  font-size: 1.18rem;
  color: var(--c-primary-700);
  line-height: 1.2;
}
.cta-card__blurb { margin: 0; color: var(--c-text-muted); font-size: 0.92rem; }
.cta-card__arrow {
  margin-top: auto;
  display: inline-flex;
  align-items: center;
  gap: 0.4rem;
  font-weight: 600;
  color: var(--c-accent);
  font-size: 0.88rem;
}
.cta-card__arrow svg {
  width: 16px;
  height: 16px;
  flex-shrink: 0;
  transition: transform var(--dur-fast) var(--ease);
}
.cta-card:hover .cta-card__arrow svg { transform: translateX(3px); }

/* ---------- Section cards (frontpage explore) ---------- */
.explore {
  margin: 4rem 0;
}
.explore__title {
  font-size: clamp(1.5rem, 1.2rem + 1vw, 2rem);
  margin: 0 0 0.4rem;
}
.explore__sub {
  color: var(--c-text-muted);
  margin: 0 0 2rem;
  max-width: 72ch;
}
.explore__group { margin: 2rem 0; }
.explore__group-head {
  display: flex;
  align-items: center;
  gap: 0.6rem;
  margin: 0 0 1rem;
}
.explore__group-head h3 {
  margin: 0;
  font-size: 1.25rem;
}
.group-icon {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  width: 28px;
  height: 28px;
  border-radius: 8px;
  flex-shrink: 0;
}
.group-icon svg { width: 18px; height: 18px; }
.group-icon--gear   { background: linear-gradient(135deg, #e7f1fb, #d7e4f3); color: #1f4f7a; }
.group-icon--funnel { background: linear-gradient(135deg, #e2f6f0, #cdebde); color: #2f8c5b; }
.group-icon--gauge  { background: linear-gradient(135deg, #fff1d6, #ffe1b8); color: #c18306; }
.cards {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(280px, 1fr));
  gap: 1rem;
}
.card {
  display: flex;
  flex-direction: column;
  gap: 0.5rem;
  padding: 1.1rem 1.2rem;
  background: var(--c-surface);
  border: 1px solid var(--c-border);
  border-radius: var(--radius-md);
  color: var(--c-text);
  text-decoration: none;
  transition: transform var(--dur-base) var(--ease),
              box-shadow var(--dur-base) var(--ease),
              border-color var(--dur-base) var(--ease);
}
.card:hover {
  transform: translateY(-3px);
  border-color: var(--c-accent-300);
  box-shadow: var(--shadow-md);
  color: var(--c-text);
}
.card__title {
  margin: 0;
  font-family: var(--font-display);
  font-size: 1.05rem;
  color: var(--c-primary-700);
  line-height: 1.3;
}
.card__blurb {
  margin: 0;
  color: var(--c-text-muted);
  font-size: 0.9rem;
  line-height: 1.5;
}

/* ---------- Prose article ----------
   Fills its container on desktop (not constrained to a narrow reading
   column). The container itself caps the maximum line length to keep prose
   readable on widescreen monitors. */
.article {
  display: grid;
  grid-template-columns: minmax(0, 1fr);
  margin: 1.5rem 0 4rem;
}
.article__inner {
  width: 100%;
  max-width: 100%;
  margin: 0;
}
.article__inner > * { max-width: 100%; }
.article h1 {
  font-size: clamp(1.9rem, 1.4rem + 1.8vw, 2.8rem);
  margin-top: 0.2rem;
  background: linear-gradient(90deg, var(--c-primary-700), var(--c-accent));
  -webkit-background-clip: text;
  background-clip: text;
  color: transparent;
  line-height: 1.15;
}
.article p { font-size: var(--fs-md); }
.article ul li::marker, .article ol li::marker { color: var(--c-accent); }
.article a { font-weight: 500; }

/* Inline code */
.article :not(pre) > code,
.prose :not(pre) > code {
  background: var(--c-code-inline-bg);
  color: var(--c-code-text);
  padding: 0.08em 0.4em;
  border-radius: 5px;
  font-family: var(--font-mono);
  font-size: 0.92em;
  border: none;
  white-space: pre-wrap;
}

/* ---------- Code blocks ---------- */
.codeblock {
  position: relative;
  margin: 1.5rem 0;
  background: var(--c-code-bg);
  border: 1px solid var(--c-code-border);
  border-radius: var(--radius-md);
  overflow: hidden;
}
.codeblock::before {
  content: attr(data-lang);
  position: absolute;
  top: 0.5rem;
  left: 0.85rem;
  font-family: var(--font-mono);
  font-size: 0.7rem;
  text-transform: uppercase;
  letter-spacing: 0.06em;
  color: var(--c-text-soft);
  pointer-events: none;
}
.codeblock pre {
  margin: 0;
  padding: 2rem 1rem 1rem;
  overflow: auto;
  font-family: var(--font-mono);
  font-size: 0.88rem;
  line-height: 1.55;
  color: var(--c-code-text);
  background: transparent;
}
.codeblock code { font-family: var(--font-mono); white-space: pre; background: transparent; padding: 0; color: inherit; }

.copy-btn {
  position: absolute;
  top: 0.4rem;
  right: 0.5rem;
  z-index: 2;
  background: var(--c-surface);
  color: var(--c-text-muted);
  border: 1px solid var(--c-border);
  border-radius: var(--radius-sm);
  padding: 0.25rem 0.6rem;
  font-size: 0.74rem;
  font-weight: 600;
  letter-spacing: 0.04em;
  text-transform: uppercase;
  transition: background var(--dur-fast) var(--ease),
              color var(--dur-fast) var(--ease),
              border-color var(--dur-fast) var(--ease),
              transform var(--dur-fast) var(--ease);
}
.copy-btn:hover {
  background: var(--c-primary);
  color: #fff;
  border-color: var(--c-primary);
}
.copy-btn.is-copied {
  background: var(--c-success);
  color: #fff;
  border-color: var(--c-success);
}

/* Mermaid */
pre.mermaid {
  margin: 1.5rem 0;
  padding: 1rem;
  background: var(--c-surface);
  border: 1px solid var(--c-border);
  border-radius: var(--radius-md);
  text-align: center;
  overflow: auto;
}

/* ASCII diagram fallback */
pre.ascii-diagram {
  margin: 1.5rem 0;
  padding: 1rem 1.2rem;
  background: var(--c-surface);
  border: 1px solid var(--c-border);
  border-radius: var(--radius-md);
  overflow: auto;
  font-family: var(--font-mono);
  font-size: 0.86rem;
  color: var(--c-text-muted);
  line-height: 1.5;
}

/* ---------- Tables ---------- */
.table-wrap {
  margin: 1.5rem 0;
  overflow-x: auto;
  -webkit-overflow-scrolling: touch;
  border: 1px solid var(--c-border);
  border-radius: var(--radius-md);
  background: var(--c-surface);
}
.table-wrap table {
  width: 100%;
  border-collapse: collapse;
  font-size: 0.93rem;
  min-width: 480px;
}
.table-wrap th, .table-wrap td {
  text-align: left;
  padding: 0.7rem 0.9rem;
  border-bottom: 1px solid var(--c-border-soft);
  vertical-align: top;
}
.table-wrap th {
  background: var(--c-surface-2);
  color: var(--c-primary-700);
  font-weight: 600;
  font-size: 0.86rem;
  letter-spacing: 0.02em;
  position: sticky;
  top: 0;
}
.table-wrap tr:last-child td { border-bottom: 0; }
.table-wrap tr:hover td { background: rgba(42,138,166,0.05); }

/* ---------- Task list (checkboxes) ---------- */
.task-list-item {
  list-style: none;
  margin-left: -1.2rem;
}
.task-list-item input[type="checkbox"] {
  margin-right: 0.55rem;
  width: 1.05em;
  height: 1.05em;
  accent-color: var(--c-accent);
  vertical-align: -0.15em;
  cursor: pointer;
}
.task-list-item input[type="checkbox"]:checked + * { text-decoration: line-through; color: var(--c-text-soft); }
.task-list-item.is-checked > * { text-decoration: line-through; color: var(--c-text-soft); }

/* Remove the leading bullet from nested task lists too */
ul:has(> .task-list-item) { list-style: none; padding-left: 0; }

/* ---------- FAQ accordion ---------- */
details.faq-item {
  background: var(--c-surface);
  border: 1px solid var(--c-border);
  border-radius: var(--radius-md);
  padding: 0;
  margin: 0.5rem 0;
  transition: box-shadow var(--dur-base) var(--ease);
}
details.faq-item[open] { box-shadow: var(--shadow-md); }
details.faq-item > summary {
  list-style: none;
  cursor: pointer;
  padding: 0.85rem 1rem;
  font-weight: 600;
  color: var(--c-primary-700);
  display: flex;
  align-items: center;
  gap: 0.6rem;
}
details.faq-item > summary::-webkit-details-marker { display: none; }
details.faq-item > summary::before {
  content: "+";
  display: inline-flex;
  align-items: center;
  justify-content: center;
  width: 1.4rem;
  height: 1.4rem;
  border-radius: 50%;
  background: var(--c-surface-2);
  color: var(--c-accent);
  font-weight: 700;
  transition: transform var(--dur-base) var(--ease);
}
details.faq-item[open] > summary::before {
  content: "−";
  transform: rotate(180deg);
}
details.faq-item > .faq-body {
  padding: 0 1rem 1rem 3rem;
  color: var(--c-text);
}

/* ---------- KaTeX harmonization ---------- */
.katex { font-size: 1.02em; }
.katex-display {
  overflow-x: auto;
  overflow-y: hidden;
  padding: 0.4rem 0;
}

/* ---------- Highlight.js theme (light, palette-matched) ---------- */
.hljs { color: var(--c-code-text); background: transparent; }
.hljs-comment, .hljs-quote { color: #7a8aa3; font-style: italic; }
.hljs-keyword, .hljs-selector-tag, .hljs-built_in, .hljs-name, .hljs-tag { color: #b04b8d; font-weight: 600; }
.hljs-string, .hljs-attr, .hljs-template-variable { color: #2f8c5b; }
.hljs-number, .hljs-literal { color: #c18306; }
.hljs-type, .hljs-class .hljs-title, .hljs-title.class_ { color: #1f4f7a; font-weight: 600; }
.hljs-function .hljs-title, .hljs-title.function_ { color: #2a8aa6; }
.hljs-variable, .hljs-params { color: #1a2533; }
.hljs-meta { color: #7a5af8; }
.hljs-symbol, .hljs-bullet { color: #c18306; }
.hljs-section { color: var(--c-primary-700); font-weight: 600; }
.hljs-emphasis { font-style: italic; }
.hljs-strong { font-weight: 700; }
.hljs-link { color: var(--c-link); text-decoration: underline; }

/* ---------- Related section ---------- */
.related {
  margin: 3rem 0 1rem;
  padding: 1.5rem;
  background: var(--c-surface);
  border: 1px solid var(--c-border);
  border-radius: var(--radius-lg);
}
.related h2 {
  font-size: 1.18rem;
  margin: 0 0 1rem;
  color: var(--c-primary-700);
}
.related__list {
  list-style: none;
  padding: 0;
  margin: 0;
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(240px, 1fr));
  gap: 0.6rem;
}
.related__list a {
  display: block;
  padding: 0.7rem 0.85rem;
  border-radius: var(--radius-md);
  background: var(--c-surface-2);
  text-decoration: none;
  color: var(--c-primary-700);
  font-weight: 500;
  font-size: 0.93rem;
  transition: background var(--dur-fast) var(--ease), transform var(--dur-fast) var(--ease);
}
.related__list a:hover {
  background: var(--c-accent-300);
  color: var(--c-primary-700);
  transform: translateY(-1px);
}

/* ---------- Section landing intro ---------- */
.section-intro {
  margin: 1.5rem 0 2.5rem;
}