/**
 * HzMinds Engineering Knowledge Center — additive stylesheet.
 *
 * This file is loaded ALONGSIDE the real site stylesheet (/css/style.css),
 * never instead of it. It does not redefine any design token (--ink,
 * --paper, --accent, --font-sans, --font-mono, --container, --radius,
 * --line-on-paper, etc.) — those all come from style.css's :root block.
 * Everything below only adds the handful of components this section
 * needs that the marketing site doesn't already have: article cards,
 * category/tag chips, table of contents, code blocks, diagrams, the
 * feedback widget, search, and pagination.
 */

/* ---------------------------------------------------------------------
   Layout helpers
--------------------------------------------------------------------- */
.eng-section { padding: 72px 0; }
.eng-section-tight { padding: 40px 0; }
.eng-grid-main {
  display: grid;
  grid-template-columns: minmax(0, 1fr) 300px;
  gap: 56px;
  align-items: start;
}
@media (max-width: 992px) {
  .eng-grid-main { grid-template-columns: minmax(0, 1fr); gap: 40px; }
}
/* Grid items default to `min-width: auto`, which refuses to shrink below
   the intrinsic content width of the widest descendant (e.g. a long,
   unwrapped line inside a <pre> code block). Without this, a single wide
   code block silently forces the whole grid track — and with it the
   entire page — wider than the viewport on mobile. `min-width: 0` lets
   the column shrink to the container's actual width so the `pre`'s own
   `overflow-x: auto` can do the scrolling instead of the page doing it. */
.eng-article-body { min-width: 0; overflow-wrap: break-word; }
.eng-breadcrumb {
  display: flex;
  flex-wrap: wrap;
  gap: 0.4rem;
  align-items: center;
  font-family: var(--font-mono);
  font-size: 0.78rem;
  color: var(--on-ink-faint);
  margin-bottom: 1.4rem;
}
.eng-breadcrumb a { color: var(--on-ink-muted); }
.eng-breadcrumb a:hover { color: var(--on-ink); }
.eng-breadcrumb span[aria-hidden] { opacity: 0.5; }
.page-hero.eng-hero { padding: calc(var(--nav-h) + 56px) 0 56px; }

/* ---------------------------------------------------------------------
   Article / index cards
--------------------------------------------------------------------- */
.eng-card-grid { display: grid; gap: 28px; grid-template-columns: repeat(3, 1fr); }
@media (max-width: 992px) { .eng-card-grid { grid-template-columns: repeat(2, 1fr); } }
@media (max-width: 700px) { .eng-card-grid { grid-template-columns: 1fr; } }
.eng-card-grid.eng-card-grid-2 { grid-template-columns: repeat(2, 1fr); }
@media (max-width: 700px) { .eng-card-grid.eng-card-grid-2 { grid-template-columns: 1fr; } }

.eng-card {
  display: flex;
  flex-direction: column;
  border: 1px solid var(--line-on-paper);
  border-radius: var(--radius);
  background: var(--paper);
  overflow: hidden;
  transition: transform var(--fast) var(--ease), box-shadow var(--fast) var(--ease), border-color var(--fast) var(--ease);
  height: 100%;
}
.eng-card:hover { transform: translateY(-3px); border-color: var(--accent); box-shadow: 0 20px 40px -28px rgba(11,13,16,0.28); }
.eng-card-media { aspect-ratio: 16/9; background: var(--paper-2); overflow: hidden; }
.eng-card-media img { width: 100%; height: 100%; object-fit: cover; display: block; }
.eng-card-body { padding: 1.5rem 1.6rem 1.7rem; display: flex; flex-direction: column; flex: 1; }
.eng-card-cat {
  font-family: var(--font-mono);
  font-size: 0.72rem;
  text-transform: uppercase;
  letter-spacing: 0.06em;
  color: var(--accent);
  margin-bottom: 0.6rem;
}
.eng-card h3, .eng-card h4 { font-size: 1.08rem; margin-bottom: 0.55rem; line-height: 1.35; }
.eng-card h3 a, .eng-card h4 a { color: inherit; }
.eng-card h3 a:hover, .eng-card h4 a:hover { color: var(--accent); }
.eng-card p.eng-card-desc { font-size: 0.92rem; color: var(--on-paper-muted); margin-bottom: 1rem; flex: 1; }
.eng-card-meta {
  display: flex;
  flex-wrap: wrap;
  gap: 0.5rem 0.9rem;
  font-family: var(--font-mono);
  font-size: 0.76rem;
  color: var(--on-paper-faint);
  margin-top: auto;
  padding-top: 0.9rem;
  border-top: 1px solid var(--line-on-paper-soft);
}
.eng-card-featured { border-color: var(--accent); }

/* Chips for categories / tags, styled like the site's existing .chip */
.eng-chip {
  display: inline-flex;
  align-items: center;
  gap: 0.35rem;
  padding: 0.35rem 0.8rem;
  border-radius: 999px;
  border: 1px solid var(--line-on-paper);
  font-family: var(--font-mono);
  font-size: 0.76rem;
  color: var(--on-paper-muted);
  transition: border-color var(--fast) var(--ease), color var(--fast) var(--ease);
}
a.eng-chip:hover { border-color: var(--accent); color: var(--on-paper); }
.eng-chip-active { border-color: var(--accent); color: var(--accent); }
.eng-chip-row { display: flex; flex-wrap: wrap; gap: 0.55rem; }
.on-ink .eng-chip { border-color: var(--line-on-ink); color: var(--on-ink-muted); }
.on-ink a.eng-chip:hover { border-color: var(--accent); color: var(--on-ink); }

/* ---------------------------------------------------------------------
   Category tiles on the landing page
--------------------------------------------------------------------- */
.eng-cat-tile {
  display: block;
  padding: 1.4rem 1.5rem;
  border: 1px solid var(--line-on-paper);
  border-radius: var(--radius);
  background: var(--paper);
  transition: border-color var(--fast) var(--ease), transform var(--fast) var(--ease);
  color: inherit;
}
.eng-cat-tile:hover { border-color: var(--accent); transform: translateY(-2px); }
.eng-cat-tile h4 { font-size: 1rem; margin-bottom: 0.4rem; }
.eng-cat-tile p { font-size: 0.85rem; color: var(--on-paper-muted); margin-bottom: 0.7rem; }
.eng-cat-tile .eng-cat-count { font-family: var(--font-mono); font-size: 0.74rem; color: var(--on-paper-faint); }

/* ---------------------------------------------------------------------
   Search
--------------------------------------------------------------------- */
.eng-search { position: relative; max-width: 480px; }
.eng-search input[type="search"] {
  width: 100%;
  padding: 0.85rem 1.1rem;
  border-radius: var(--radius);
  border: 1px solid var(--line-on-paper);
  background: var(--paper);
  color: var(--on-paper);
  font-family: var(--font-sans);
  font-size: 0.96rem;
}
.eng-search input[type="search"]:focus { outline: none; border-color: var(--accent); }
.eng-search-results {
  position: absolute;
  top: calc(100% + 8px);
  left: 0;
  right: 0;
  background: var(--paper);
  border: 1px solid var(--line-on-paper);
  border-radius: var(--radius);
  box-shadow: 0 24px 48px -24px rgba(11,13,16,0.35);
  max-height: 420px;
  overflow-y: auto;
  z-index: 40;
}
.eng-search-results[hidden] { display: none; }
.eng-search-result { display: block; padding: 0.85rem 1.1rem; border-bottom: 1px solid var(--line-on-paper-soft); color: inherit; }
.eng-search-result:last-child { border-bottom: none; }
.eng-search-result:hover, .eng-search-result.is-active { background: var(--paper-2); }
.eng-search-result strong { display: block; font-size: 0.94rem; margin-bottom: 0.2rem; }
.eng-search-result span { font-size: 0.8rem; color: var(--on-paper-faint); font-family: var(--font-mono); }
.eng-search-empty { padding: 1rem 1.1rem; font-size: 0.88rem; color: var(--on-paper-faint); }

/* ---------------------------------------------------------------------
   Article page
--------------------------------------------------------------------- */
.eng-article-header { padding: calc(var(--nav-h) + 48px) 0 40px; background: var(--ink); color: var(--on-ink); }
.eng-article-header .eng-breadcrumb { color: var(--on-ink-faint); }
.eng-article-header .eng-breadcrumb a { color: var(--on-ink-muted); }
.eng-article-header h1 { color: var(--on-ink); max-width: 22ch; margin-bottom: 1.1rem; }
.eng-article-header .eng-card-desc { color: var(--on-ink-muted); font-size: 1.1rem; max-width: 60ch; margin-bottom: 1.6rem; }
.eng-article-meta {
  display: flex;
  flex-wrap: wrap;
  gap: 1.4rem;
  font-family: var(--font-mono);
  font-size: 0.82rem;
  color: var(--on-ink-faint);
}
.eng-article-meta strong { color: var(--on-ink-muted); font-weight: 500; }

.eng-article-body {
  font-size: 1.06rem;
  line-height: 1.75;
  color: var(--on-paper);
  max-width: 74ch;
}
.eng-article-body h2 {
  font-size: 1.55rem;
  margin: 2.6rem 0 1rem;
  scroll-margin-top: calc(var(--nav-h) + 20px);
}
.eng-article-body h3 {
  font-size: 1.2rem;
  margin: 2rem 0 0.8rem;
  scroll-margin-top: calc(var(--nav-h) + 20px);
}
.eng-article-body h2 a.header-anchor,
.eng-article-body h3 a.header-anchor {
  color: inherit;
  text-decoration: none;
  border-bottom: none;
}
.eng-article-body p { margin: 0 0 1.3rem; }
.eng-article-body ul, .eng-article-body ol { margin: 0 0 1.3rem; padding-left: 1.4rem; }
.eng-article-body li { margin-bottom: 0.45rem; }
/* :not(.btn) matters here: without it, this rule's specificity
   (class + element) beats style.css's plain ".btn-accent" class rule,
   overwriting its white button text with orange-on-orange — which is
   exactly what made the "Talk to us" button at the end of every article
   unreadable. Buttons keep style.css's own color/no-underline. */
.eng-article-body a:not(.btn) { color: var(--accent); text-decoration: underline; text-underline-offset: 2px; }
.eng-article-body a:not(.btn):hover { color: var(--accent-dim); }
.eng-article-body blockquote {
  margin: 1.6rem 0;
  padding: 1rem 1.4rem;
  border-left: 3px solid var(--accent);
  background: var(--paper-2);
  border-radius: 0 var(--radius-sm) var(--radius-sm) 0;
  color: var(--on-paper-muted);
}
.eng-article-body img { max-width: 100%; border-radius: var(--radius-sm); }
.eng-article-body table {
  width: 100%;
  border-collapse: collapse;
  margin: 1.6rem 0;
  font-size: 0.94rem;
}
.eng-article-body th, .eng-article-body td {
  border: 1px solid var(--line-on-paper);
  padding: 0.6rem 0.8rem;
  text-align: left;
  vertical-align: top;
}
.eng-article-body th { background: var(--paper-2); font-weight: 650; }
.eng-table-wrap { overflow-x: auto; margin: 1.6rem 0; }
.eng-table-wrap table { margin: 0; }

/* Code blocks (Prism, applied at build time — no client JS) */
.eng-article-body pre[class*="language-"] {
  margin: 1.6rem 0;
  padding: 1.2rem 1.4rem;
  border-radius: var(--radius-sm);
  background: var(--ink);
  color: var(--on-ink);
  overflow-x: auto;
  font-family: var(--font-mono);
  font-size: 0.86rem;
  line-height: 1.65;
  -webkit-overflow-scrolling: touch;
}
.eng-article-body code[class*="language-"] { font-family: var(--font-mono); }
.eng-article-body :not(pre) > code {
  font-family: var(--font-mono);
  font-size: 0.88em;
  background: var(--paper-2);
  border: 1px solid var(--line-on-paper);
  border-radius: 4px;
  padding: 0.1em 0.4em;
  /* Long identifiers (Namespace.Qualified.Names, sys.dm_db_*, etc.) have
     no natural break points — without this, one long inline code span
     forces the whole line, and with it the page, wider than the
     viewport on mobile instead of wrapping. */
  overflow-wrap: anywhere;
}
.token.comment, .token.prolog, .token.doctype, .token.cdata { color: var(--on-ink-faint); font-style: italic; }
.token.keyword, .token.selector, .token.tag { color: #ff8a68; }
.token.string, .token.attr-value, .token.builtin { color: #9fd88a; }
.token.function, .token.class-name { color: #7ec7ff; }
.token.number, .token.boolean, .token.constant { color: #e6c07b; }
.token.operator, .token.punctuation { color: var(--on-ink-muted); }
.token.property, .token.attr-name { color: #b39ddb; }

.eng-code-caption {
  font-family: var(--font-mono);
  font-size: 0.78rem;
  color: var(--on-paper-faint);
  margin: -1.1rem 0 1.6rem;
}

/* Mermaid diagrams — rendered to static SVG at BUILD TIME (see
   scripts/render-mermaid.js). No mermaid.js ships to the browser. */
.diagram-figure { margin: 2rem 0; }
.mermaid-diagram {
  border: 1px solid var(--line-on-paper);
  border-radius: var(--radius-sm);
  background: var(--paper);
  padding: 1.4rem;
  overflow-x: auto;
  text-align: center;
}
.mermaid-diagram svg { max-width: 100%; height: auto; }
.mermaid-diagram .mermaid-source { display: none; } /* visually hidden fallback source; kept for text-search + a11y tooling */
.diagram-figure figcaption {
  font-family: var(--font-mono);
  font-size: 0.8rem;
  color: var(--on-paper-faint);
  text-align: center;
  margin-top: 0.8rem;
}

/* ---------------------------------------------------------------------
   Table of contents
--------------------------------------------------------------------- */
.eng-toc {
  position: sticky;
  top: calc(var(--nav-h) + 24px);
  border: 1px solid var(--line-on-paper);
  border-radius: var(--radius);
  padding: 1.3rem 1.4rem;
  background: var(--paper);
}
.eng-toc h5 {
  font-family: var(--font-mono);
  font-size: 0.76rem;
  text-transform: uppercase;
  letter-spacing: 0.06em;
  color: var(--on-paper-faint);
  margin-bottom: 0.9rem;
}
.eng-toc ol { list-style: none; margin: 0; padding: 0; display: flex; flex-direction: column; gap: 0.55rem; }
.eng-toc ol ol { padding-left: 1rem; margin-top: 0.55rem; }
.eng-toc a {
  font-size: 0.87rem;
  color: var(--on-paper-muted);
  display: block;
  line-height: 1.4;
  border-left: 2px solid transparent;
  padding-left: 0.7rem;
}
.eng-toc a:hover { color: var(--on-paper); }
.eng-toc a.is-active { color: var(--accent); border-left-color: var(--accent); }
@media (max-width: 992px) {
  .eng-toc { position: static; margin-bottom: 2rem; }
  .eng-toc[data-toc-collapsible] ol { display: none; }
  .eng-toc[data-toc-collapsible].is-open ol { display: flex; }
  .eng-toc-toggle { display: flex; width: 100%; justify-content: space-between; align-items: center; background: none; border: none; cursor: pointer; padding: 0; font: inherit; color: inherit; }
}
.eng-toc-toggle { display: none; }
.eng-toc-toggle span {
  font-family: var(--font-mono);
  font-size: 0.76rem;
  text-transform: uppercase;
  letter-spacing: 0.06em;
  color: var(--on-paper-faint);
}
.eng-toc-toggle svg { transition: transform var(--fast) var(--ease); flex: none; }
.eng-toc.is-open .eng-toc-toggle svg { transform: rotate(180deg); }
@media (max-width: 992px) {
  .eng-toc-toggle { display: flex; }
  .eng-toc-title-static { display: none; }
}

/* ---------------------------------------------------------------------
   Share
--------------------------------------------------------------------- */
.eng-share { display: flex; flex-wrap: wrap; gap: 0.6rem; margin: 2rem 0; }
.eng-share-btn {
  display: inline-flex;
  align-items: center;
  gap: 0.4rem;
  padding: 0.55rem 1rem;
  border-radius: 999px;
  border: 1px solid var(--line-on-paper);
  font-size: 0.85rem;
  color: var(--on-paper-muted);
  background: none;
  cursor: pointer;
  font-family: var(--font-sans);
  transition: border-color var(--fast) var(--ease), color var(--fast) var(--ease);
}
.eng-share-btn:hover { border-color: var(--accent); color: var(--on-paper); }
.eng-share-btn svg { width: 15px; height: 15px; }

/* ---------------------------------------------------------------------
   Feedback widget
--------------------------------------------------------------------- */
.eng-feedback {
  margin: 3rem 0 1rem;
  padding: 1.8rem 2rem;
  border: 1px solid var(--line-on-paper);
  border-radius: var(--radius);
  background: var(--paper-2);
}
.eng-feedback h4 { font-size: 1.05rem; margin-bottom: 1rem; }
.eng-feedback-rows { display: flex; flex-direction: column; gap: 1.3rem; }
.eng-feedback-helpful { display: flex; align-items: center; gap: 1rem; flex-wrap: wrap; }
.eng-feedback-helpful .eng-fb-btn {
  display: inline-flex;
  align-items: center;
  gap: 0.5rem;
  padding: 0.6rem 1.1rem;
  border-radius: var(--radius-sm);
  border: 1px solid var(--line-on-paper);
  background: var(--paper);
  cursor: pointer;
  font-size: 0.92rem;
  font-family: var(--font-sans);
  color: var(--on-paper);
}
.eng-feedback-helpful .eng-fb-btn:hover { border-color: var(--accent); }
.eng-feedback-helpful .eng-fb-btn.is-selected { border-color: var(--accent); color: var(--accent); }
.eng-fb-stars { display: inline-flex; gap: 0.25rem; }
.eng-fb-star {
  background: none;
  border: none;
  cursor: pointer;
  padding: 2px;
  color: var(--line-on-paper);
  font-size: 1.4rem;
  line-height: 1;
}
.eng-fb-star.is-active, .eng-fb-star.is-hover { color: var(--accent); }
.eng-feedback textarea {
  width: 100%;
  min-height: 90px;
  padding: 0.8rem 1rem;
  border-radius: var(--radius-sm);
  border: 1px solid var(--line-on-paper);
  background: var(--paper);
  color: var(--on-paper);
  font-family: var(--font-sans);
  font-size: 0.92rem;
  resize: vertical;
}
.eng-feedback textarea:focus { outline: none; border-color: var(--accent); }
.eng-feedback .eng-fb-submit-row { display: flex; align-items: center; gap: 1rem; }
.eng-feedback-success {
  padding: 1rem 1.2rem;
  border-radius: var(--radius-sm);
  background: rgba(255,90,54,0.1);
  color: var(--on-paper);
  font-size: 0.92rem;
}
.eng-feedback-success[hidden], .eng-feedback-form[hidden] { display: none; }
.eng-feedback-error { color: var(--accent); font-size: 0.85rem; margin-top: 0.5rem; }

/* ---------------------------------------------------------------------
   Related articles + contact CTA
--------------------------------------------------------------------- */
.eng-related { padding: 3rem 0; border-top: 1px solid var(--line-on-paper); margin-top: 2rem; }
.eng-related h3 { font-size: 1.2rem; margin-bottom: 1.6rem; }

.eng-contact-cta {
  margin: 3rem 0;
  padding: 2rem 2.2rem;
  border-radius: var(--radius);
  background: var(--ink);
  color: var(--on-ink);
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 1.5rem;
  flex-wrap: wrap;
}
.eng-contact-cta p { margin: 0; font-size: 1.05rem; max-width: 46ch; color: var(--on-ink-muted); }
.eng-contact-cta .btn { flex: none; }

/* ---------------------------------------------------------------------
   Pagination (category / tag pages)
--------------------------------------------------------------------- */
.eng-pagination { display: flex; justify-content: center; gap: 0.6rem; margin-top: 2.5rem; }
.eng-pagination a, .eng-pagination span {
  min-width: 40px;
  height: 40px;
  display: inline-flex;
  align-items: center;
  justify-content: center;
  border-radius: var(--radius-sm);
  border: 1px solid var(--line-on-paper);
  font-family: var(--font-mono);
  font-size: 0.85rem;
  color: var(--on-paper-muted);
}
.eng-pagination a:hover { border-color: var(--accent); color: var(--on-paper); }
.eng-pagination .is-current { border-color: var(--accent); color: var(--accent); }

/* ---------------------------------------------------------------------
   Empty states
--------------------------------------------------------------------- */
.eng-empty { padding: 3rem 0; text-align: center; color: var(--on-paper-faint); }