/* ==========================================================================
   LightTrace blog — shared stylesheet.
   Design tokens and chrome mirror frontend/public/landing.html so the blog
   reads as one product. One cached file for every post + the index.
   ========================================================================== */

:root {
  --bg: #0e1016;
  --bg-2: #0a0c11;
  --surface: #161922;
  --surface-2: #1d212c;
  --border: #262b38;
  --text: #e8eaf0;
  --muted: #8b93a7;
  --faint: #5b6274;
  --primary: #8b7cff;
  --primary-dim: #6b5cd6;
  --fatal: #ff4d6d;
  --error: #ff6b57;
  --warning: #ffb020;
  --info: #4aa3ff;
  --ok: #37d29b;
  --maxw: 1160px;
  --prose: 720px;
}

* { box-sizing: border-box; }
html { scroll-behavior: smooth; -webkit-text-size-adjust: 100%; }

body {
  margin: 0;
  background: var(--bg);
  color: var(--text);
  font-family: "Inter", -apple-system, BlinkMacSystemFont, "Segoe UI", Roboto, sans-serif;
  font-size: 16px;
  line-height: 1.65;
  -webkit-font-smoothing: antialiased;
  -moz-osx-font-smoothing: grayscale;
  overflow-x: hidden;
}

/* ambient backdrop: purple glow + faint grid (matches landing) */
body::before {
  content: "";
  position: fixed;
  inset: 0;
  z-index: -2;
  background:
    radial-gradient(900px 520px at 82% -8%, rgba(139, 124, 255, 0.16), transparent 60%),
    radial-gradient(720px 480px at 6% 4%, rgba(255, 107, 87, 0.06), transparent 55%);
}
body::after {
  content: "";
  position: fixed;
  inset: 0;
  z-index: -1;
  background-image:
    linear-gradient(var(--border) 1px, transparent 1px),
    linear-gradient(90deg, var(--border) 1px, transparent 1px);
  background-size: 56px 56px;
  opacity: 0.08;
  mask-image: radial-gradient(circle at 50% 12%, black, transparent 70%);
  -webkit-mask-image: radial-gradient(circle at 50% 12%, black, transparent 70%);
}

h1, h2, h3, h4, .display {
  font-family: "Space Grotesk", -apple-system, BlinkMacSystemFont, "Segoe UI", Roboto, sans-serif;
  margin: 0;
  font-weight: 700;
  letter-spacing: -0.02em;
  color: var(--text);
}
a { color: var(--primary); text-decoration: none; }
a:hover { color: var(--text); }
.mono { font-family: "JetBrains Mono", ui-monospace, "Courier New", monospace; }

.wrap { width: 100%; max-width: var(--maxw); margin: 0 auto; padding: 0 24px; }

/* ---- buttons (match landing) ------------------------------------------- */
.btn {
  display: inline-flex; align-items: center; gap: 8px;
  font-family: "Space Grotesk", sans-serif; font-weight: 600; font-size: 14px;
  padding: 11px 18px; border-radius: 11px; border: 1px solid transparent;
  cursor: pointer; transition: transform .12s ease, background .12s ease, border-color .12s ease;
  white-space: nowrap;
}
.btn:hover { transform: translateY(-1px); }
.btn-primary { background: var(--primary); color: #12101f; }
.btn-primary:hover { background: #9d90ff; color: #12101f; }
.btn-ghost { background: var(--surface); color: var(--text); border-color: var(--border); }
.btn-ghost:hover { background: var(--surface-2); color: var(--text); }
.btn-lg { padding: 14px 22px; font-size: 15px; border-radius: 13px; }

/* ---- nav --------------------------------------------------------------- */
.nav { position: sticky; top: 0; z-index: 50; background: rgba(14, 16, 22, 0.78);
  backdrop-filter: saturate(140%) blur(12px); border-bottom: 1px solid var(--border); }
.nav-inner { display: flex; align-items: center; justify-content: space-between; height: 62px; gap: 18px; }
.brand { display: inline-flex; align-items: center; gap: 10px; font-family: "Space Grotesk", sans-serif;
  font-weight: 700; font-size: 17px; color: var(--text); letter-spacing: -0.01em; }
.brand .mark { width: 26px; height: 26px; }
.nav-links { display: flex; gap: 22px; align-items: center; }
.nav-links a { color: var(--muted); font-size: 14px; font-weight: 500; }
.nav-links a:hover { color: var(--text); }
.nav-cta { display: flex; gap: 10px; align-items: center; }

/* ---- footer ------------------------------------------------------------ */
footer { border-top: 1px solid var(--border); padding: 30px 0; margin-top: 72px; }
.foot { display: flex; align-items: center; justify-content: space-between; gap: 16px;
  flex-wrap: wrap; color: var(--faint); font-size: 13px; }
.foot a { color: var(--muted); }
.foot a:hover { color: var(--text); }
.foot .brand { font-size: 15px; }
.foot .brand .mark { width: 22px; height: 22px; }

/* ==========================================================================
   INDEX PAGE
   ========================================================================== */
.blog-hero { padding: 72px 0 26px; text-align: center; }
.blog-hero .eyebrow { font-family: "JetBrains Mono", monospace; font-size: 12px; letter-spacing: 0.12em;
  text-transform: uppercase; color: var(--primary); }
.blog-hero h1 { font-size: clamp(32px, 5vw, 50px); margin-top: 14px; line-height: 1.05; }
.blog-hero p { color: var(--muted); font-size: 18px; max-width: 620px; margin: 16px auto 0; }

.cluster-nav { display: flex; flex-wrap: wrap; gap: 10px; justify-content: center; margin: 30px 0 8px; }
.chip { display: inline-flex; align-items: center; gap: 7px; padding: 7px 14px; border-radius: 999px;
  border: 1px solid var(--border); background: var(--surface); color: var(--muted); font-size: 13px;
  font-weight: 500; transition: border-color .12s, color .12s, background .12s; }
.chip:hover { color: var(--text); border-color: color-mix(in srgb, var(--primary) 45%, var(--border)); }

.section-head { display: flex; align-items: baseline; justify-content: space-between; gap: 16px;
  margin: 56px 0 20px; }
.section-head h2 { font-size: 22px; }
.section-head p { color: var(--faint); font-size: 14px; margin: 4px 0 0; }
.section-head .count { font-family: "JetBrains Mono", monospace; font-size: 12px; color: var(--faint); }

.card-grid { display: grid; grid-template-columns: repeat(3, 1fr); gap: 18px; }
.card-grid.two { grid-template-columns: repeat(2, 1fr); }

.post-card { display: flex; flex-direction: column; background: var(--surface); border: 1px solid var(--border);
  border-radius: 16px; padding: 22px; transition: transform .14s ease, border-color .14s ease, background .14s ease; }
.post-card:hover { transform: translateY(-3px); border-color: color-mix(in srgb, var(--primary) 45%, var(--border));
  background: var(--surface-2); }
.post-card .kicker { font-family: "JetBrains Mono", monospace; font-size: 11px; letter-spacing: 0.06em;
  text-transform: uppercase; color: var(--primary); }
.post-card h3 { font-size: 18px; margin-top: 10px; line-height: 1.3; color: var(--text); }
.post-card p { color: var(--muted); font-size: 14px; margin: 10px 0 0; }
.post-card .card-meta { margin-top: 16px; padding-top: 14px; border-top: 1px solid var(--border);
  display: flex; gap: 12px; color: var(--faint); font-size: 12px; font-family: "JetBrains Mono", monospace; }

.featured .post-card { background: linear-gradient(180deg, var(--surface-2), var(--surface)); }
.featured .post-card.big { grid-column: span 1; }

/* ==========================================================================
   ARTICLE PAGE
   ========================================================================== */
.breadcrumb { display: flex; gap: 8px; align-items: center; padding: 26px 0 0; color: var(--faint);
  font-size: 13px; flex-wrap: wrap; }
.breadcrumb a { color: var(--muted); }
.breadcrumb a:hover { color: var(--text); }
.breadcrumb .sep { color: var(--faint); }

.article-header { padding: 22px 0 26px; max-width: 780px; }
.article-header .kicker { font-family: "JetBrains Mono", monospace; font-size: 12px; letter-spacing: 0.08em;
  text-transform: uppercase; color: var(--primary); }
.article-header h1 { font-size: clamp(30px, 4.4vw, 44px); line-height: 1.08; margin-top: 14px; }
.article-header .dek { color: var(--muted); font-size: 19px; line-height: 1.55; margin-top: 16px; }
.article-meta { display: flex; align-items: center; gap: 14px; margin-top: 22px; color: var(--faint);
  font-size: 13px; font-family: "JetBrains Mono", monospace; flex-wrap: wrap; }
.article-meta .dot { width: 3px; height: 3px; border-radius: 50%; background: var(--faint); }

.article-layout { display: grid; grid-template-columns: minmax(0, 1fr) 232px; gap: 56px; align-items: start;
  padding-top: 8px; }

/* table of contents */
.toc { position: sticky; top: 84px; font-size: 13px; border-left: 1px solid var(--border); padding-left: 16px; }
.toc .toc-title { font-family: "JetBrains Mono", monospace; font-size: 11px; letter-spacing: 0.08em;
  text-transform: uppercase; color: var(--faint); margin-bottom: 12px; }
.toc ul { list-style: none; margin: 0; padding: 0; display: grid; gap: 9px; }
.toc a { color: var(--muted); display: block; line-height: 1.4; }
.toc a:hover { color: var(--text); }
.toc li.lvl-3 { padding-left: 14px; }
.toc li.lvl-3 a { color: var(--faint); font-size: 12.5px; }

/* ==========================================================================
   PROSE
   ========================================================================== */
.prose { max-width: var(--prose); font-size: 17px; line-height: 1.75; color: #d6dae6; }
.prose > * + * { margin-top: 22px; }
.prose p { margin: 0; }
.prose h2 { font-size: 27px; margin: 52px 0 0; line-height: 1.2; scroll-margin-top: 84px; }
.prose h3 { font-size: 20px; margin: 38px 0 0; line-height: 1.3; scroll-margin-top: 84px; color: var(--text); }
.prose h2 a.anchor, .prose h3 a.anchor { color: inherit; }
.prose h2 a.anchor:hover, .prose h3 a.anchor:hover { color: var(--primary); }
.prose a { color: var(--primary); text-decoration: none; border-bottom: 1px solid color-mix(in srgb, var(--primary) 40%, transparent); }
.prose a:hover { color: #a99bff; border-bottom-color: currentColor; }
.prose strong { color: var(--text); font-weight: 600; }
.prose ul, .prose ol { margin: 0; padding-left: 24px; }
.prose li { margin: 8px 0; }
.prose li::marker { color: var(--faint); }
.prose blockquote { margin: 0; padding: 6px 20px; border-left: 3px solid var(--primary);
  background: color-mix(in srgb, var(--primary) 7%, transparent); border-radius: 0 10px 10px 0; color: var(--muted); }
.prose blockquote p { margin: 6px 0; }
.prose hr { border: none; border-top: 1px solid var(--border); margin: 40px 0; }
.prose img { max-width: 100%; border-radius: 12px; border: 1px solid var(--border); }

/* inline code */
.prose :not(pre) > code { font-family: "JetBrains Mono", monospace; font-size: 0.86em;
  background: var(--surface-2); border: 1px solid var(--border); border-radius: 6px; padding: 1.5px 6px; color: #cbd0e0; }

/* shiki code blocks */
.prose pre { margin: 0; border: 1px solid var(--border); border-radius: 14px; padding: 18px 20px;
  overflow-x: auto; font-size: 13.5px; line-height: 1.7; box-shadow: 0 20px 50px -34px rgba(0,0,0,0.7);
  background: #0b0d13 !important; }
.prose pre code { font-family: "JetBrains Mono", monospace; display: block; }
.prose pre.shiki span { background: transparent !important; }

/* tables */
.prose table { width: 100%; border-collapse: collapse; font-size: 14.5px; display: block; overflow-x: auto; }
.prose thead th { text-align: left; font-family: "Space Grotesk", sans-serif; font-size: 13px; color: var(--text);
  border-bottom: 1px solid var(--border); padding: 10px 14px; white-space: nowrap; }
.prose tbody td { border-bottom: 1px solid var(--border); padding: 10px 14px; color: var(--muted); vertical-align: top; }
.prose tbody tr:hover td { background: color-mix(in srgb, var(--surface) 60%, transparent); }

/* ---- callouts (MDX <Callout>) ------------------------------------------ */
.callout { display: flex; gap: 13px; padding: 16px 18px; border-radius: 13px; border: 1px solid var(--border);
  background: var(--surface); margin: 26px 0; }
.callout .ico { flex: none; width: 20px; height: 20px; margin-top: 1px; }
.callout .callout-body { font-size: 15px; color: var(--muted); line-height: 1.6; }
.callout .callout-body > * + * { margin-top: 8px; }
.callout .callout-body strong { color: var(--text); }
.callout.info { border-color: color-mix(in srgb, var(--info) 40%, var(--border)); }
.callout.info .ico { color: var(--info); }
.callout.tip { border-color: color-mix(in srgb, var(--ok) 40%, var(--border)); }
.callout.tip .ico { color: var(--ok); }
.callout.warn { border-color: color-mix(in srgb, var(--warning) 45%, var(--border)); }
.callout.warn .ico { color: var(--warning); }

/* ---- in-article CTA (MDX <CTA/> and end-of-post) ----------------------- */
.post-cta { margin: 40px 0 0; padding: 26px; border-radius: 16px; border: 1px solid color-mix(in srgb, var(--primary) 45%, var(--border));
  background: linear-gradient(180deg, var(--surface-2), var(--surface));
  box-shadow: 0 26px 60px -40px rgba(139,124,255,0.6); }
.post-cta h3 { font-size: 20px; }
.post-cta p { color: var(--muted); font-size: 15px; margin: 8px 0 0; }
.post-cta .hero-actions { display: flex; gap: 12px; margin-top: 18px; flex-wrap: wrap; }

/* ---- author + related -------------------------------------------------- */
.article-footer { max-width: var(--prose); margin-top: 44px; padding-top: 26px; border-top: 1px solid var(--border); }
.byline { display: flex; align-items: center; gap: 13px; }
.byline .avatar { width: 42px; height: 42px; border-radius: 12px; background: linear-gradient(135deg, var(--primary-dim), var(--primary));
  display: grid; place-items: center; color: #12101f; font-family: "Space Grotesk", sans-serif; font-weight: 700; }
.byline .who { font-size: 14px; color: var(--text); font-weight: 600; }
.byline .who span { display: block; color: var(--faint); font-weight: 400; font-size: 13px; font-family: "JetBrains Mono", monospace; }

.related { margin-top: 20px; }
.related h2 { font-size: 20px; margin-bottom: 18px; }

/* ==========================================================================
   RESPONSIVE
   ========================================================================== */
@media (max-width: 960px) {
  .article-layout { grid-template-columns: 1fr; gap: 0; }
  .toc { display: none; }
  .card-grid, .card-grid.two { grid-template-columns: 1fr 1fr; }
}
@media (max-width: 680px) {
  .nav-links { display: none; }
  .card-grid, .card-grid.two { grid-template-columns: 1fr; }
  .prose { font-size: 16px; }
  .blog-hero { padding: 48px 0 18px; }
}