/* ============================================================
   Infernix Engineering Journal — blog-specific styles
   Layers on top of ../styles.css (tokens, header, footer, buttons).
   ============================================================ */

/* ---------------------------------------------------------- layout */
.journal-wrap {
  width: min(1120px, calc(100% - 48px));
  margin-inline: auto;
}

.article-wrap {
  width: min(760px, calc(100% - 48px));
  margin-inline: auto;
}

/* ------------------------------------------------------ blog hero */
.journal-hero {
  padding: 120px 0 56px;
  border-bottom: 1px solid var(--line);
}

.journal-hero .eyebrow { margin: 0 0 18px; }

.journal-hero h1 {
  font-family: var(--font-display);
  font-size: clamp(44px, 6vw, 68px);
  font-weight: 700;
  letter-spacing: -.02em;
  line-height: 1.04;
  margin: 0 0 20px;
}

.journal-intro {
  color: var(--muted);
  font-size: 16.5px;
  line-height: 1.7;
  max-width: 640px;
  margin: 0;
}

/* ------------------------------------------------- filter toolbar */
.filter-bar {
  display: flex;
  flex-wrap: wrap;
  align-items: center;
  gap: 10px;
  padding: 28px 0 8px;
}

.filter-label {
  font-family: var(--font-mono);
  font-size: 11px;
  letter-spacing: .14em;
  color: var(--dim);
  margin-right: 6px;
}

.filter-chip {
  font-family: var(--font-mono);
  font-size: 11.5px;
  letter-spacing: .06em;
  text-transform: uppercase;
  color: var(--muted);
  background: transparent;
  border: 1px solid var(--line);
  border-radius: 999px;
  padding: 7px 14px;
  cursor: pointer;
  transition: color .18s ease, border-color .18s ease, background .18s ease;
}

.filter-chip:hover { color: var(--text); border-color: var(--line-strong); }

.filter-chip[aria-pressed="true"] {
  color: var(--bg);
  background: var(--accent);
  border-color: var(--accent);
}

.filter-chip:focus-visible {
  outline: 2px solid var(--cyan);
  outline-offset: 2px;
}

.filter-search {
  margin-left: auto;
  display: flex;
  align-items: center;
  gap: 8px;
  border: 1px solid var(--line);
  border-radius: 8px;
  padding: 6px 12px;
  background: var(--bg-raise);
}

.filter-search:focus-within { border-color: var(--line-strong); }

.filter-search label {
  font-family: var(--font-mono);
  font-size: 11px;
  letter-spacing: .1em;
  color: var(--dim);
}

.filter-search input {
  background: transparent;
  border: 0;
  color: var(--text);
  font-family: var(--font-mono);
  font-size: 13px;
  width: 160px;
  outline: none;
}

.filter-search input::placeholder { color: var(--dim); }

.filter-count {
  font-family: var(--font-mono);
  font-size: 11.5px;
  color: var(--dim);
  padding: 10px 0 0;
  min-height: 1.4em;
}

/* ------------------------------------------------ featured article */
.featured-article {
  display: grid;
  grid-template-columns: 1.15fr .85fr;
  gap: 44px;
  align-items: center;
  margin: 40px 0 64px;
  padding: 40px;
  border: 1px solid var(--line);
  background:
    radial-gradient(600px 300px at 90% 0%, rgba(255, 159, 46, .06), transparent 60%),
    var(--bg-raise);
  border-radius: 4px;
}

.featured-flag {
  display: inline-flex;
  align-items: center;
  gap: 8px;
  font-family: var(--font-mono);
  font-size: 11px;
  letter-spacing: .16em;
  color: var(--accent);
  margin-bottom: 16px;
}

.featured-flag::before {
  content: "";
  width: 8px;
  height: 8px;
  background: var(--accent);
  border-radius: 50%;
}

.featured-article h2 {
  font-family: var(--font-display);
  font-size: clamp(26px, 3vw, 34px);
  font-weight: 700;
  letter-spacing: -.01em;
  line-height: 1.15;
  margin: 0 0 14px;
}

.featured-article h2 a { color: var(--text); text-decoration: none; }
.featured-article h2 a:hover { color: var(--accent); }

.featured-summary {
  color: var(--muted);
  font-size: 14.5px;
  line-height: 1.7;
  margin: 0 0 20px;
}

.featured-media {
  border: 1px solid var(--line);
  border-radius: 3px;
  overflow: hidden;
  background: var(--panel);
}

.featured-media img { display: block; width: 100%; height: auto; }

/* -------------------------------------------------- article cards */
.article-grid {
  display: grid;
  grid-template-columns: repeat(auto-fill, minmax(310px, 1fr));
  gap: 22px;
  padding-bottom: 96px;
}

.article-card {
  display: flex;
  flex-direction: column;
  border: 1px solid var(--line);
  border-radius: 4px;
  background: var(--bg-raise);
  padding: 28px;
  transition: border-color .2s ease, transform .2s ease;
}

.article-card:hover { border-color: var(--line-strong); transform: translateY(-2px); }

.article-card[hidden] { display: none; }

.card-cats {
  display: flex;
  flex-wrap: wrap;
  gap: 8px;
  margin-bottom: 14px;
}

.cat-tag {
  font-family: var(--font-mono);
  font-size: 10.5px;
  letter-spacing: .1em;
  text-transform: uppercase;
  color: var(--cyan);
  border: 1px solid rgba(53, 212, 244, .3);
  border-radius: 999px;
  padding: 3px 10px;
}

.cat-tag.draft {
  color: var(--accent);
  border-color: rgba(255, 159, 46, .35);
}

.article-card h3 {
  font-family: var(--font-display);
  font-size: 20px;
  font-weight: 650;
  letter-spacing: -.01em;
  line-height: 1.25;
  margin: 0 0 12px;
}

.article-card h3 a { color: var(--text); text-decoration: none; }
.article-card h3 a:hover { color: var(--accent); }
.article-card h3 a:focus-visible { outline: 2px solid var(--cyan); outline-offset: 3px; }

.card-summary {
  color: var(--muted);
  font-size: 13.5px;
  line-height: 1.65;
  margin: 0 0 20px;
  flex: 1;
}

.card-meta {
  display: flex;
  flex-wrap: wrap;
  gap: 6px 14px;
  font-family: var(--font-mono);
  font-size: 11px;
  letter-spacing: .06em;
  color: var(--dim);
  border-top: 1px solid var(--line);
  padding-top: 16px;
}

.card-meta .meta-date { color: var(--muted); }

/* =============================================== article page === */
.article-header {
  padding: 110px 0 44px;
  border-bottom: 1px solid var(--line);
}

.back-link {
  display: inline-flex;
  align-items: center;
  gap: 8px;
  font-family: var(--font-mono);
  font-size: 11.5px;
  letter-spacing: .1em;
  text-transform: uppercase;
  color: var(--muted);
  text-decoration: none;
  margin-bottom: 36px;
}

.back-link:hover { color: var(--accent); }

.article-header h1 {
  font-family: var(--font-display);
  font-size: clamp(32px, 4.6vw, 48px);
  font-weight: 700;
  letter-spacing: -.02em;
  line-height: 1.1;
  margin: 16px 0 16px;
}

.article-subtitle {
  color: var(--muted);
  font-size: 17px;
  line-height: 1.65;
  margin: 0 0 28px;
}

.article-byline {
  display: flex;
  flex-wrap: wrap;
  gap: 8px 20px;
  font-family: var(--font-mono);
  font-size: 12px;
  letter-spacing: .05em;
  color: var(--dim);
}

.article-byline strong { color: var(--text); font-weight: 500; }

.draft-banner {
  margin-top: 28px;
  border: 1px dashed rgba(255, 159, 46, .5);
  background: rgba(255, 159, 46, .06);
  border-radius: 4px;
  padding: 16px 20px;
  font-size: 13.5px;
  line-height: 1.6;
  color: var(--muted);
}

.draft-banner strong { color: var(--accent); }

/* ---------------------------------------------------------- layout */
.article-layout {
  display: grid;
  grid-template-columns: 210px minmax(0, 1fr);
  gap: 56px;
  padding: 56px 0 96px;
  align-items: start;
}

/* ------------------------------------------------------------- TOC */
.toc {
  position: sticky;
  top: calc(var(--header-h, 64px) + 24px);
  border-left: 1px solid var(--line);
  padding-left: 18px;
  font-size: 12.5px;
  line-height: 1.5;
}

.toc-label {
  font-family: var(--font-mono);
  font-size: 10.5px;
  letter-spacing: .16em;
  color: var(--dim);
  margin: 0 0 12px;
}

.toc ol {
  list-style: none;
  margin: 0;
  padding: 0;
  display: grid;
  gap: 9px;
}

.toc a {
  color: var(--muted);
  text-decoration: none;
  display: block;
  border-left: 2px solid transparent;
  margin-left: -19px;
  padding-left: 17px;
  transition: color .15s ease, border-color .15s ease;
}

.toc a:hover, .toc a[aria-current="true"] { color: var(--text); border-left-color: var(--accent); }

/* ------------------------------------------------------ prose */
.prose { min-width: 0; }

.prose > * + * { margin-top: 22px; }

.prose h2 {
  font-family: var(--font-display);
  font-size: 27px;
  font-weight: 700;
  letter-spacing: -.01em;
  margin: 52px 0 18px;
  scroll-margin-top: calc(var(--header-h, 64px) + 20px);
}

.prose h3 {
  font-family: var(--font-display);
  font-size: 19px;
  font-weight: 650;
  margin: 36px 0 14px;
  scroll-margin-top: calc(var(--header-h, 64px) + 20px);
}

.prose p { color: var(--muted); font-size: 15.5px; line-height: 1.8; margin: 0; }

.prose a { color: var(--cyan); text-decoration: underline; text-underline-offset: 3px; text-decoration-thickness: 1px; }
.prose a:hover { color: var(--accent); }

.prose strong { color: var(--text); font-weight: 600; }

.prose ul, .prose ol { color: var(--muted); font-size: 15.5px; line-height: 1.8; padding-left: 22px; margin: 0; }
.prose li + li { margin-top: 8px; }

.prose code {
  font-family: var(--font-mono);
  font-size: .88em;
  background: var(--panel);
  border: 1px solid var(--line);
  border-radius: 4px;
  padding: .12em .4em;
  color: var(--text);
}

.prose blockquote {
  margin: 0;
  border-left: 2px solid var(--accent);
  padding: 4px 0 4px 20px;
  color: var(--text);
  font-size: 16.5px;
  line-height: 1.7;
}

/* --------------------------------------------------- data tables */
.prose .data-table {
  width: 100%;
  border-collapse: collapse;
  font-size: 13.5px;
}

.prose .data-table th {
  font-family: var(--font-mono);
  font-size: 10.5px;
  letter-spacing: .12em;
  text-transform: uppercase;
  color: var(--dim);
  text-align: left;
  border-bottom: 1px solid var(--line-strong);
  padding: 10px 14px 10px 0;
}

.prose .data-table td {
  color: var(--muted);
  border-bottom: 1px solid var(--line);
  padding: 11px 14px 11px 0;
  vertical-align: top;
}

.prose .data-table td:first-child { color: var(--text); }
.prose .data-table .num { font-family: var(--font-mono); color: var(--text); }

/* ---------------------------------------------------- code block */
.code-block {
  position: relative;
  border: 1px solid var(--line);
  border-radius: 4px;
  background: var(--panel);
  overflow: hidden;
}

.code-block .code-lang {
  display: block;
  font-family: var(--font-mono);
  font-size: 10.5px;
  letter-spacing: .14em;
  text-transform: uppercase;
  color: var(--dim);
  padding: 10px 16px 0;
}

.code-block pre {
  margin: 0;
  padding: 12px 16px 18px;
  overflow-x: auto;
}

.code-block code {
  font-family: var(--font-mono);
  font-size: 13px;
  line-height: 1.65;
  color: var(--text);
  background: none;
  border: 0;
  padding: 0;
  white-space: pre;
}

.copy-btn {
  position: absolute;
  top: 8px;
  right: 8px;
  font-family: var(--font-mono);
  font-size: 10.5px;
  letter-spacing: .1em;
  text-transform: uppercase;
  color: var(--muted);
  background: var(--bg-raise);
  border: 1px solid var(--line);
  border-radius: 4px;
  padding: 5px 10px;
  cursor: pointer;
  transition: color .15s ease, border-color .15s ease;
}

.copy-btn:hover { color: var(--text); border-color: var(--line-strong); }
.copy-btn:focus-visible { outline: 2px solid var(--cyan); outline-offset: 2px; }
.copy-btn.copied { color: var(--cyan); border-color: var(--cyan); }

html.js .copy-btn { display: block; }
html:not(.js) .copy-btn { display: none; }

/* tokens (tiny highlighter in blog.js) */
.tok-kw { color: #ff9f2e; }
.tok-str { color: #35d4f4; }
.tok-num { color: #c8a6ff; }
.tok-com { color: #78859a; font-style: italic; }
.tok-fn { color: #f3f4f6; }
.tok-op { color: #9aa5b5; }

/* ------------------------------------------------------ callouts */
.callout {
  border: 1px solid var(--line);
  border-left-width: 3px;
  border-radius: 4px;
  background: var(--bg-raise);
  padding: 20px 24px;
}

.callout-label {
  display: block;
  font-family: var(--font-mono);
  font-size: 10.5px;
  letter-spacing: .14em;
  text-transform: uppercase;
  margin-bottom: 8px;
}

.callout p { margin: 0; font-size: 14.5px; }

.callout.decision { border-left-color: var(--cyan); }
.callout.decision .callout-label { color: var(--cyan); }

.callout.tradeoff { border-left-color: var(--accent); }
.callout.tradeoff .callout-label { color: var(--accent); }

.callout.failure { border-left-color: #f06a6a; }
.callout.failure .callout-label { color: #f06a6a; }

.callout.lesson { border-left-color: #7fd99a; }
.callout.lesson .callout-label { color: #7fd99a; }

/* ------------------------------------------------------- figures */
.prose figure { margin: 34px 0; }

.prose figure img {
  display: block;
  width: 100%;
  height: auto;
  border: 1px solid var(--line);
  border-radius: 3px;
  background: var(--panel);
}

.prose figcaption {
  font-family: var(--font-mono);
  font-size: 11.5px;
  letter-spacing: .04em;
  color: var(--dim);
  margin-top: 10px;
  line-height: 1.6;
}

/* ----------------------------------------- references / related */
.ref-list {
  list-style: none;
  padding: 0;
  margin: 0;
  display: grid;
  gap: 10px;
}

.ref-list li {
  font-size: 14px;
  color: var(--muted);
  line-height: 1.6;
  border-left: 1px solid var(--line);
  padding-left: 16px;
}

.article-end {
  margin-top: 64px;
  border-top: 1px solid var(--line);
  padding-top: 40px;
}

.related-grid {
  display: grid;
  grid-template-columns: repeat(auto-fill, minmax(260px, 1fr));
  gap: 18px;
  margin-top: 18px;
}

.related-card {
  border: 1px solid var(--line);
  border-radius: 4px;
  background: var(--bg-raise);
  padding: 22px;
  text-decoration: none;
  display: block;
  transition: border-color .18s ease;
}

.related-card:hover { border-color: var(--line-strong); }

.related-card .rc-cat {
  font-family: var(--font-mono);
  font-size: 10.5px;
  letter-spacing: .12em;
  text-transform: uppercase;
  color: var(--cyan);
}

.related-card .rc-title {
  display: block;
  font-family: var(--font-display);
  font-size: 16px;
  font-weight: 650;
  color: var(--text);
  margin-top: 8px;
  line-height: 1.3;
}

.related-card:hover .rc-title { color: var(--accent); }

/* --------------------------------------------------- breakpoints */
@media (max-width: 980px) {
  .featured-article { grid-template-columns: 1fr; }
  .featured-media { order: -1; }
  .article-layout { grid-template-columns: 1fr; gap: 0; }
  .toc {
    position: static;
    border-left: 0;
    border-top: 1px solid var(--line);
    border-bottom: 1px solid var(--line);
    padding: 18px 0;
    margin-bottom: 36px;
  }
  .toc a { margin-left: 0; padding-left: 12px; border-left-width: 2px; }
}

@media (max-width: 560px) {
  .journal-wrap, .article-wrap { width: calc(100% - 32px); }
  .journal-hero { padding-top: 96px; }
  .article-header { padding-top: 90px; }
  .featured-article { padding: 24px; }
  .filter-search { margin-left: 0; width: 100%; }
  .filter-search input { width: 100%; }
  .prose h2 { font-size: 23px; }
}