/* ── The Brief — blog listing + article layout ─────────────────────────────
   Productionised from the founder's design bundles (team/design-reference/).
   Reuses tokens + components from style.css (blog-*, article-*, faq-*);
   this file only adds what the founder design introduces. */

/* ── Listing ─────────────────────────────────────────────────────────── */
.brief-filter-bar { display: flex; align-items: center; justify-content: space-between; gap: 1rem; padding: 1.25rem 0; border-top: 1px solid var(--line); border-bottom: 1px solid var(--line); margin-bottom: 1.75rem; }
.brief-filter-chips { display: flex; gap: 0.5rem; flex-wrap: wrap; }
.brief-filter-chip { cursor: pointer; padding: 0.4375rem 0.875rem; border-radius: 999px; font-size: 0.8125rem; font-weight: 500; color: var(--ink); background: transparent; border: 1px solid var(--line); font-family: inherit; white-space: nowrap; transition: border-color var(--transition); }
.brief-filter-chip:hover { border-color: var(--navy); }
.brief-filter-chip.on { font-weight: 700; color: #fff; background: var(--navy); border-color: var(--navy); }
.brief-filter-sort { display: flex; align-items: center; gap: 0.625rem; font-family: var(--font-mono); font-size: 0.75rem; color: var(--muted); letter-spacing: 0.08em; white-space: nowrap; }
.brief-filter-sort strong { background: var(--surface); color: var(--ink); padding: 0.4375rem 0.875rem; border: 1px solid var(--line); border-radius: 6px; font-weight: 700; font-size: 0.75rem; }
.brief-card-byline { display: flex; align-items: center; justify-content: space-between; border-top: 1px dashed var(--line); padding-top: 0.75rem; margin-top: 0.25rem; font-family: var(--font-mono); font-size: 0.75rem; color: var(--muted); letter-spacing: 0.04em; }
.brief-newsletter { background: var(--navy); color: #fff; border-radius: var(--radius-lg); padding: 1.75rem 2.25rem; display: grid; grid-template-columns: 1.2fr auto; gap: 2.25rem; align-items: center; position: relative; overflow: hidden; margin: 2.5rem 0 0.5rem; }
.brief-newsletter-eyebrow { font-size: 0.75rem; font-family: var(--font-mono); letter-spacing: 0.22em; color: var(--ochre); font-weight: 800; margin-bottom: 0.625rem; }
.brief-newsletter h2 { font-size: clamp(1.375rem, 2.5vw, 1.75rem); font-weight: 700; letter-spacing: -0.02em; line-height: 1.15; margin: 0; }
.brief-newsletter p { font-size: 0.875rem; margin: 0.625rem 0 0; opacity: 0.78; line-height: 1.5; }
.brief-newsletter-btn { background: var(--ochre); color: var(--ink); padding: 0.875rem 1.375rem; font-size: 0.8125rem; font-weight: 700; border-radius: 8px; text-decoration: none; white-space: nowrap; }
.brief-newsletter-btn:hover { background: var(--gold-light); color: var(--ink); }

/* ── Article layout: TOC rail · body · side rail ─────────────────────── */
.brief-layout { display: grid; grid-template-columns: 180px minmax(0, 720px) 220px; gap: 3rem; align-items: start; margin: 2rem 0; }
.brief-toc { position: sticky; top: 1.5rem; font-family: var(--font-mono); font-size: 0.75rem; }
.brief-toc-eyebrow { color: var(--muted); letter-spacing: 0.16em; font-weight: 700; margin-bottom: 0.875rem; text-transform: uppercase; }
.brief-toc a { display: flex; gap: 0.625rem; padding: 0.5rem 0 0.5rem 0.625rem; color: var(--muted); font-weight: 500; border-left: 2px solid transparent; margin-left: -0.75rem; line-height: 1.4; text-decoration: none; }
.brief-toc a:hover, .brief-toc a.on { color: var(--ink); font-weight: 700; border-left-color: var(--ochre); }
.brief-toc a .n { color: var(--ochre); font-weight: 800; }
.brief-toc-time-label { color: var(--muted); letter-spacing: 0.16em; font-weight: 700; margin: 2rem 0 0.875rem; text-transform: uppercase; }
.brief-toc-time { font-size: 2rem; color: var(--ink); font-weight: 800; letter-spacing: -0.02em; }
.brief-progress-track { height: 4px; background: var(--line); border-radius: 2px; margin-top: 0.5rem; }
.brief-progress-fill { height: 4px; width: 0%; background: var(--ochre); border-radius: 2px; }
.brief-author-avatar { width: 40px; height: 40px; border-radius: 50%; background: var(--ochre); color: var(--ink); display: grid; place-items: center; font-weight: 800; font-size: 0.8125rem; font-family: var(--font-mono); letter-spacing: 0.04em; flex-shrink: 0; }
.brief-author-row { display: flex; align-items: center; gap: 0.75rem; margin-bottom: 0.75rem; }
.brief-author-name { font-size: 0.8125rem; font-weight: 700; }
.brief-author-role { font-size: 0.6875rem; color: var(--muted); }
.brief-author-bio { font-size: 0.75rem; color: var(--muted); line-height: 1.55; }
.brief-rail-calc { padding: 0.6875rem 0; border-top: 1px dashed var(--line); font-size: 0.8125rem; font-weight: 600; display: flex; justify-content: space-between; align-items: baseline; gap: 0.5rem; color: var(--ink); text-decoration: none; }
.brief-rail-calc:first-of-type { border-top: none; }
.brief-rail-calc:hover { color: var(--navy); }
.brief-rail-calc .arr { color: var(--ochre); font-family: var(--font-mono); font-size: 0.6875rem; font-weight: 800; }
.brief-share-grid { display: grid; grid-template-columns: 1fr 1fr; gap: 0.375rem; }
.brief-share-grid a, .brief-share-grid button { background: var(--surface-alt); color: var(--ink); padding: 0.625rem 0; text-align: center; font-weight: 800; font-size: 0.6875rem; border-radius: 6px; font-family: var(--font-mono); letter-spacing: 0.12em; text-decoration: none; border: 0; cursor: pointer; }
.brief-share-grid a:hover, .brief-share-grid button:hover { background: var(--line); }

/* ── Hero stat panel (navy) ──────────────────────────────────────────── */
.brief-hero-panel { background: var(--navy); border-radius: var(--radius-lg); padding: 2.5rem 3rem; position: relative; overflow: hidden; margin: 2.25rem 0 0.5rem; }
.brief-hero-panel::before { content: ''; position: absolute; inset: 0; background: radial-gradient(circle at 80% 20%, rgba(245, 230, 194, 0.19) 0%, transparent 55%); }
.brief-hero-panel > * { position: relative; }
.brief-hero-kicker { font-family: var(--font-mono); font-size: 0.6875rem; color: var(--ochre); letter-spacing: 0.22em; font-weight: 800; margin-bottom: 0.5rem; }
.brief-hero-stats { display: flex; align-items: flex-end; gap: 2.5rem 3.5rem; margin-top: 1.25rem; flex-wrap: wrap; }
.brief-hero-stat-label { font-family: var(--font-mono); font-size: 0.6875rem; color: var(--navy-soft); letter-spacing: 0.14em; margin-bottom: 0.375rem; text-transform: uppercase; }
.brief-hero-stat-value { font-family: var(--font-mono); font-size: clamp(2.25rem, 5vw, 3.5rem); font-weight: 800; letter-spacing: -0.03em; line-height: 1; color: var(--ochre); }
.brief-hero-stat-value.soft { color: var(--navy-soft); }
.brief-hero-stat-value.flag { color: #e8897b; }
.brief-hero-stat-note { font-size: 0.8125rem; color: rgba(255,255,255,0.67); margin-top: 0.5rem; }
.brief-hero-source { margin-top: 2rem; font-family: var(--font-mono); font-size: 0.6875rem; color: var(--navy-soft); letter-spacing: 0.12em; text-transform: uppercase; }

/* ── Embed / reuse note ──────────────────────────────────────────────── */
.brief-embed-note { background: var(--surface-alt); border: 1px dashed var(--line); border-radius: 10px; padding: 1rem 1.375rem; margin: 1.75rem 0; font-size: 0.875rem; color: var(--muted); line-height: 1.6; }
.brief-embed-note strong { color: var(--ink); }

/* ── Keep reading ────────────────────────────────────────────────────── */
.brief-keep-reading { padding: 2.5rem 0 0.5rem; border-top: 1px solid var(--line); margin-top: 3rem; }
.brief-keep-reading-head { display: flex; align-items: baseline; justify-content: space-between; margin-bottom: 1.375rem; }
.brief-keep-reading-head h2 { font-size: clamp(1.5rem, 3vw, 2rem); letter-spacing: -0.025em; font-weight: 700; margin: 0; }
.brief-keep-reading-head span { font-family: var(--font-mono); font-size: 0.6875rem; color: var(--muted); letter-spacing: 0.12em; font-weight: 700; }
.brief-keep-grid { display: grid; grid-template-columns: repeat(3, 1fr); gap: 1rem; }
.brief-keep-card { text-decoration: none; color: var(--ink); background: var(--surface); border: 1px solid var(--line); border-radius: 12px; padding: 1.125rem; display: flex; flex-direction: column; gap: 0.625rem; transition: border-color var(--transition), transform var(--transition); }
.brief-keep-card:hover { border-color: var(--navy); transform: translateY(-2px); color: var(--ink); }
.brief-keep-card-meta { display: flex; justify-content: space-between; align-items: center; }
.brief-keep-card-tag { background: var(--navy); color: #fff; padding: 0.1875rem 0.5rem; border-radius: 4px; font-family: var(--font-mono); font-size: 0.625rem; font-weight: 700; letter-spacing: 0.08em; }
.brief-keep-card-min { font-family: var(--font-mono); font-size: 0.6875rem; color: var(--muted); letter-spacing: 0.08em; font-weight: 700; }
.brief-keep-card h3 { font-size: 1rem; font-weight: 700; letter-spacing: -0.015em; line-height: 1.3; margin: 0; }
.brief-keep-card p { font-size: 0.8125rem; color: var(--muted); line-height: 1.45; margin: 0; }

/* ── Responsive ──────────────────────────────────────────────────────── */
@media (max-width: 1080px) {
  .brief-layout { grid-template-columns: minmax(0, 1fr) 220px; }
  .brief-toc { display: none; }
}
@media (max-width: 860px) {
  .brief-layout { grid-template-columns: 1fr; gap: 1.75rem; }
  .brief-rail-article { position: static; }
  .brief-newsletter { grid-template-columns: 1fr; gap: 1.25rem; padding: 1.5rem 1.375rem; }
  .brief-filter-bar { flex-direction: column; align-items: flex-start; gap: 0.75rem; }
  .brief-keep-grid { grid-template-columns: 1fr; }
  .brief-hero-panel { padding: 1.75rem 1.375rem; }
  .brief-hero-stats { gap: 1.5rem 2rem; }
}

/* Anchor scroll stops at the bottom of the sticky site header (founder, 23 Jul) */
main [id] { scroll-margin-top: 5.5rem; }