/* =========================================================================
   VS-Trade blog — design tokens + editorial stylesheet
   Tokens mirror the DESIGN package (vstrade-r003-pipeline/handoff/assets/
   tokens.css), adapted for screen (not print). Keep in sync when DESIGN
   ships a new palette. Single stylesheet for the whole /blog/ subtree.
   ========================================================================= */

@import url('https://fonts.googleapis.com/css2?family=Inter:wght@400;500;600;700&family=Source+Serif+4:ital,opsz,wght@0,8..60,400;0,8..60,600;0,8..60,700;1,8..60,400&family=JetBrains+Mono:wght@400;500&display=swap');

:root {
  /* Palette — from DESIGN tokens.css */
  --vst-paper: #FAF9F5;
  --vst-paper-2: #F5F5F0;
  --vst-rule: #E4E2DA;
  --vst-rule-2: #D4D2C9;
  --vst-mute-3: #B8B6AC;
  --vst-mute-2: #8B8B83;
  --vst-mute-1: #5A5A53;
  --vst-ink: #2C2C2C;
  --vst-navy-900: #0A1929;
  --vst-navy-700: #1B2B4D;
  --vst-amber-600: #D98300;
  --vst-amber-500: #FFA000;
  --vst-amber-100: #FFF1D6;
  --vst-blue-700: #003F99;
  --vst-blue-600: #005FCC;

  /* Semantic */
  --bg: var(--vst-paper);
  --bg-alt: var(--vst-paper-2);
  --fg: var(--vst-navy-900);
  --fg-muted: var(--vst-mute-1);
  --fg-subtle: var(--vst-mute-2);
  --link: var(--vst-blue-600);
  --link-hover: var(--vst-blue-700);
  --rule: var(--vst-rule);
  --accent: var(--vst-amber-600);

  /* Type */
  --font-sans: 'Inter', -apple-system, BlinkMacSystemFont, 'Segoe UI', sans-serif;
  --font-serif: 'Source Serif 4', Georgia, 'Times New Roman', serif;
  --font-mono: 'JetBrains Mono', ui-monospace, 'SF Mono', Menlo, monospace;

  --measure: 720px;
}

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

html, body {
  margin: 0;
  padding: 0;
  background: var(--bg);
  color: var(--fg);
  font-family: var(--font-sans);
  -webkit-font-smoothing: antialiased;
  text-rendering: optimizeLegibility;
}

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

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

/* ── Site chrome (header / footer) ─────────────────────────────────────── */
.blog-header {
  border-bottom: 1px solid var(--rule);
  background: var(--bg);
}
.blog-header__inner,
.blog-footer__inner {
  max-width: 960px;
  margin: 0 auto;
  padding: 18px 24px;
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 16px;
}
.blog-wordmark {
  font-family: var(--font-serif);
  font-size: 18px;
  font-weight: 700;
  letter-spacing: .3px;
  color: var(--vst-navy-900);
}
.blog-wordmark:hover { color: var(--vst-navy-900); }
.blog-nav a {
  font-size: 13px;
  font-weight: 500;
  color: var(--fg-muted);
  margin-left: 20px;
}
.blog-nav a:hover { color: var(--vst-navy-900); }

.blog-footer {
  margin-top: 72px;
  border-top: 1px solid var(--rule);
  background: var(--bg-alt);
}
.blog-footer__inner {
  display: block;
  font-size: 12px;
  line-height: 1.7;
  color: var(--fg-subtle);
}
.blog-footer a { color: var(--vst-blue-700); }

/* ── Post layout ───────────────────────────────────────────────────────── */
.post {
  max-width: var(--measure);
  margin: 0 auto;
  padding: 56px 24px 0;
}
.post__eyebrow {
  font-family: var(--font-mono);
  font-size: 11px;
  letter-spacing: .14em;
  text-transform: uppercase;
  color: var(--fg-subtle);
  margin-bottom: 14px;
}
.post__title {
  font-family: var(--font-serif);
  font-size: 40px;
  line-height: 1.14;
  letter-spacing: -.018em;
  font-weight: 700;
  margin: 0 0 18px;
}
.post__meta {
  display: flex;
  flex-wrap: wrap;
  align-items: center;
  gap: 8px 14px;
  font-size: 13px;
  color: var(--fg-subtle);
  padding-bottom: 28px;
  border-bottom: 1px solid var(--rule);
}
.post__meta .dot { color: var(--vst-mute-3); }
.post__cover {
  margin: 32px 0 8px;
}
.post__cover img {
  width: 100%;
  border: 1px solid var(--rule);
  border-radius: 4px;
  display: block;
}

/* Body typography */
.post__body {
  font-size: 18px;
  line-height: 1.7;
  color: var(--vst-ink);
  padding: 16px 0 8px;
}
.post__body > *:first-child { margin-top: 0; }
.post__body p { margin: 0 0 22px; }
.post__body h2 {
  font-family: var(--font-serif);
  font-size: 28px;
  line-height: 1.22;
  letter-spacing: -.01em;
  font-weight: 600;
  color: var(--vst-navy-900);
  margin: 44px 0 14px;
}
.post__body h3 {
  font-family: var(--font-serif);
  font-size: 21px;
  line-height: 1.3;
  font-weight: 600;
  color: var(--vst-navy-900);
  margin: 34px 0 10px;
}
.post__body a { text-decoration: underline; text-underline-offset: 2px; }
.post__body strong { color: var(--vst-navy-900); }
.post__body ul, .post__body ol { margin: 0 0 22px; padding-left: 24px; }
.post__body li { margin: 6px 0; }
.post__body blockquote {
  margin: 28px 0;
  padding: 6px 0 6px 22px;
  border-left: 3px solid var(--vst-amber-600);
  color: var(--fg-muted);
  font-style: italic;
}
.post__body blockquote p:last-child { margin-bottom: 0; }
.post__body code {
  font-family: var(--font-mono);
  font-size: .86em;
  background: var(--bg-alt);
  border: 1px solid var(--rule);
  border-radius: 3px;
  padding: 1px 5px;
}
.post__body pre {
  font-family: var(--font-mono);
  font-size: 13.5px;
  line-height: 1.6;
  background: var(--vst-navy-900);
  color: #E8ECF2;
  border-radius: 6px;
  padding: 18px 20px;
  overflow-x: auto;
  margin: 0 0 24px;
}
.post__body pre code { background: none; border: 0; padding: 0; color: inherit; font-size: inherit; }
.post__body hr { border: 0; border-top: 1px solid var(--rule); margin: 36px 0; }

/* Figures (inline images) */
.post__body figure { margin: 30px 0; }
.post__body figure img {
  width: 100%;
  border: 1px solid var(--rule);
  border-radius: 4px;
  display: block;
}
.post__body figure figcaption {
  font-size: 13px;
  color: var(--fg-subtle);
  margin-top: 8px;
  text-align: center;
}

/* ── Post footer (CTA + tags + bio) ────────────────────────────────────── */
.post__footer {
  max-width: var(--measure);
  margin: 8px auto 0;
  padding: 0 24px;
}
.post-cta {
  margin: 40px 0 28px;
  padding: 24px 26px;
  background: var(--vst-navy-900);
  border-radius: 6px;
  color: var(--vst-paper);
}
.post-cta h3 {
  font-family: var(--font-serif);
  font-size: 20px;
  font-weight: 600;
  margin: 0 0 8px;
  color: var(--vst-paper);
}
.post-cta p { font-size: 14px; line-height: 1.6; color: #B6BFCC; margin: 0 0 16px; }
.post-cta a.btn {
  display: inline-block;
  background: var(--vst-amber-600);
  color: var(--vst-paper);
  font-size: 14px;
  font-weight: 600;
  padding: 11px 20px;
  border-radius: 4px;
}
.post-cta a.btn:hover { background: var(--vst-amber-500); }

.post-tags { margin: 24px 0; display: flex; flex-wrap: wrap; gap: 8px; }
.post-tags a {
  font-family: var(--font-mono);
  font-size: 11px;
  letter-spacing: .04em;
  text-transform: uppercase;
  color: var(--fg-muted);
  background: var(--bg-alt);
  border: 1px solid var(--rule);
  border-radius: 999px;
  padding: 4px 12px;
}
.post-tags a:hover { color: var(--vst-navy-900); border-color: var(--vst-mute-3); }

.post-bio {
  display: flex;
  gap: 14px;
  align-items: flex-start;
  margin: 28px 0 0;
  padding-top: 24px;
  border-top: 1px solid var(--rule);
  font-size: 14px;
  line-height: 1.6;
  color: var(--fg-muted);
}
.post-bio strong { color: var(--vst-navy-900); }

/* ── Index / listing ───────────────────────────────────────────────────── */
.index-head {
  max-width: 960px;
  margin: 0 auto;
  padding: 64px 24px 28px;
}
.index-head .eyebrow {
  font-family: var(--font-mono);
  font-size: 11px;
  letter-spacing: .14em;
  text-transform: uppercase;
  color: var(--fg-subtle);
  margin-bottom: 14px;
}
.index-head h1 {
  font-family: var(--font-serif);
  font-size: 44px;
  line-height: 1.1;
  letter-spacing: -.02em;
  font-weight: 700;
  margin: 0 0 12px;
}
.index-head p { font-size: 17px; line-height: 1.55; color: var(--fg-muted); margin: 0; max-width: 620px; }

.post-list {
  max-width: 960px;
  margin: 0 auto;
  padding: 8px 24px;
  display: grid;
  gap: 28px;
}
.post-card {
  display: grid;
  grid-template-columns: 220px 1fr;
  gap: 22px;
  padding: 24px 0;
  border-top: 1px solid var(--rule);
}
.post-card:first-child { border-top: 0; }
.post-card--no-thumb { grid-template-columns: 1fr; }
.post-card__thumb img {
  width: 100%;
  aspect-ratio: 1200 / 630;
  object-fit: cover;
  border: 1px solid var(--rule);
  border-radius: 4px;
  display: block;
}
.post-card__date {
  font-family: var(--font-mono);
  font-size: 11px;
  letter-spacing: .06em;
  text-transform: uppercase;
  color: var(--fg-subtle);
  margin-bottom: 8px;
}
.post-card__title {
  font-family: var(--font-serif);
  font-size: 24px;
  line-height: 1.2;
  letter-spacing: -.012em;
  font-weight: 600;
  margin: 0 0 8px;
}
.post-card__title a { color: var(--vst-navy-900); }
.post-card__title a:hover { color: var(--vst-blue-700); }
.post-card__desc { font-size: 15px; line-height: 1.55; color: var(--fg-muted); margin: 0 0 12px; }
.post-card__tags { display: flex; flex-wrap: wrap; gap: 6px; }
.post-card__tags button,
.post-card__tags a {
  font-family: var(--font-mono);
  font-size: 10.5px;
  letter-spacing: .04em;
  text-transform: uppercase;
  color: var(--fg-muted);
  background: var(--bg-alt);
  border: 1px solid var(--rule);
  border-radius: 999px;
  padding: 3px 10px;
  cursor: pointer;
}

.index-empty {
  max-width: 960px;
  margin: 0 auto;
  padding: 24px;
  color: var(--fg-muted);
}

/* Tag filter bar */
.tag-filter {
  max-width: 960px;
  margin: 0 auto;
  padding: 4px 24px 8px;
  display: flex;
  flex-wrap: wrap;
  gap: 8px;
  align-items: center;
}
.tag-filter .label { font-size: 12px; color: var(--fg-subtle); margin-right: 4px; }
.tag-filter button {
  font-family: var(--font-mono);
  font-size: 11px;
  letter-spacing: .04em;
  text-transform: uppercase;
  color: var(--fg-muted);
  background: var(--bg);
  border: 1px solid var(--rule);
  border-radius: 999px;
  padding: 4px 12px;
  cursor: pointer;
}
.tag-filter button[aria-pressed="true"] {
  color: var(--vst-paper);
  background: var(--vst-navy-900);
  border-color: var(--vst-navy-900);
}

@media (max-width: 720px) {
  .post__title { font-size: 30px; }
  .index-head h1 { font-size: 32px; }
  .post__body { font-size: 17px; }
  .post-card { grid-template-columns: 1fr; }
  .post-card__thumb { max-width: 320px; }
}