/* ============================================================
   THE BELUM BRIEF — beyond.belum.ai
   Standalone stylesheet in the belum.ai design language
   (DM Serif Display / Instrument Sans, ink + paper + copper).
   Tokens mirror src/pages/home-v2.css; keep them in step.
   ============================================================ */

:root {
  --ink: #0a0c10;
  --ink-2: #12151c;
  --ink-3: #171b24;
  --paper: #f6f4f0;
  --paper-2: #eae6df;

  --copper: #c45a3c;
  --copper-lt: #e07a5e;
  --pine: #2a6f6a;
  --brass: #a8472b;

  --on-ink: #f6f4f0;
  --on-ink-mute: #d4cfc6;
  --on-ink-faint: #8b8579;
  --on-paper: #12151a;
  --on-paper-mute: #45403a;

  --line-ink: rgba(246, 244, 240, 0.13);
  --line-ink-soft: rgba(246, 244, 240, 0.07);
  --line-paper: rgba(22, 25, 29, 0.13);
  --line-paper-soft: rgba(22, 25, 29, 0.07);

  --serif: 'DM Serif Display', Georgia, 'Times New Roman', serif;
  --sans: 'Instrument Sans', system-ui, -apple-system, sans-serif;

  --nav-h: 72px;
  --gutter: clamp(1.25rem, 5vw, 3rem);
}

* { box-sizing: border-box; }
html { -webkit-text-size-adjust: 100%; }
body {
  margin: 0;
  background: var(--ink);
  color: var(--on-ink);
  font-family: var(--sans);
  font-size: 16px;
  line-height: 1.6;
  -webkit-font-smoothing: antialiased;
  text-rendering: optimizeLegibility;
  overflow-x: hidden;
}
img { max-width: 100%; height: auto; }
a { color: inherit; }
h1, h2, h3, h4, h5 { margin: 0; font-weight: 400; }

.wrap {
  width: min(100% - 2 * var(--gutter), 74rem);
  margin: 0 auto;
}

/* ── Nav ──────────────────────────────────────────────── */

.nav {
  position: sticky;
  top: 0;
  z-index: 50;
  height: var(--nav-h);
  background: rgba(10, 12, 16, 0.86);
  backdrop-filter: blur(12px);
  -webkit-backdrop-filter: blur(12px);
  border-bottom: 1px solid var(--line-ink-soft);
}
.nav-inner {
  height: 100%;
  display: flex;
  align-items: center;
  gap: 1.5rem;
}
.nav-logo { display: flex; align-items: center; }
.nav-logo img { height: 28px; width: auto; }
.nav-title {
  font-family: var(--serif);
  font-size: 1.25rem;
  color: var(--on-ink);
  text-decoration: none;
  padding-left: 1.5rem;
  border-left: 1px solid var(--line-ink);
  white-space: nowrap;
}
.nav-links {
  margin-left: auto;
  display: flex;
  align-items: center;
  gap: 1.75rem;
}
.nav-links a {
  font-size: 0.9rem;
  font-weight: 500;
  color: var(--on-ink-mute);
  text-decoration: none;
  transition: color 0.2s ease;
}
.nav-links a:hover, .nav-links a[aria-current="page"] { color: var(--on-ink); }
.nav-links .nav-ext {
  padding: 0.5rem 1rem;
  border: 1px solid var(--line-ink);
  border-radius: 999px;
}
.nav-links .nav-ext:hover { border-color: var(--copper-lt); color: var(--copper-lt); }

/* ── Hero (ink) ───────────────────────────────────────── */

.hero {
  position: relative;
  padding: clamp(3.5rem, 8vw, 6.5rem) 0 clamp(2.75rem, 6vw, 4.5rem);
  background:
    radial-gradient(60rem 30rem at 85% -10%, rgba(196, 90, 60, 0.16), transparent 60%),
    linear-gradient(180deg, var(--ink-2) 0%, var(--ink) 100%);
  overflow: hidden;
}
.hero--short { padding-bottom: clamp(2rem, 5vw, 3.5rem); }
.hero-eyebrow {
  display: inline-flex;
  align-items: center;
  gap: 0.6rem;
  font-size: 0.74rem;
  font-weight: 600;
  letter-spacing: 0.14em;
  text-transform: uppercase;
  color: var(--copper-lt);
  margin-bottom: 1.4rem;
}
.hero-eyebrow .dot {
  width: 6px; height: 6px; border-radius: 50%;
  background: var(--copper-lt);
  box-shadow: 0 0 0 4px rgba(224, 122, 94, 0.18);
}
.hero h1 {
  font-family: var(--serif);
  font-size: clamp(2.1rem, 4.6vw, 3.9rem);
  line-height: 1.08;
  letter-spacing: -0.01em;
  max-width: 24ch;
  color: var(--on-ink);
  text-wrap: balance;
}
.hero-sub {
  margin: 1.4rem 0 0;
  max-width: 58ch;
  font-size: 1.14rem;
  line-height: 1.65;
  color: var(--on-ink-mute);
  text-wrap: pretty;
}
.hero-sub a { color: var(--copper-lt); }
.hero--post .hero-sub {
  font-family: var(--serif);
  font-size: clamp(1.25rem, 2vw, 1.55rem);
  line-height: 1.35;
  color: var(--on-ink-mute);
}
.hero-meta {
  margin-top: 2.25rem;
  padding-top: 1.5rem;
  border-top: 1px solid var(--line-ink);
  font-size: 0.86rem;
  letter-spacing: 0.06em;
  text-transform: uppercase;
  color: var(--on-ink-faint);
}

.blog-back {
  display: flex;
  width: fit-content;
  align-items: center;
  gap: 0.5rem;
  font-size: 0.85rem;
  font-weight: 600;
  letter-spacing: 0.1em;
  text-transform: uppercase;
  color: var(--on-ink-faint);
  text-decoration: none;
  margin-bottom: 1.5rem;
  transition: color 0.2s ease;
}
.blog-back:hover { color: var(--copper-lt); }
.blog-back::before { content: "\2190"; }

.post-meta {
  display: flex;
  flex-wrap: wrap;
  align-items: center;
  gap: 0.5rem 1.1rem;
  margin-top: 2.25rem;
  padding-top: 1.5rem;
  border-top: 1px solid var(--line-ink);
  font-size: 0.9rem;
  color: var(--on-ink-faint);
}
.post-meta .who { color: var(--on-ink); font-weight: 600; }
.post-meta .sep { opacity: 0.4; }

/* ── Paper section ────────────────────────────────────── */

.s-paper {
  background: var(--paper);
  color: var(--on-paper);
  padding: clamp(3rem, 6vw, 5rem) 0 clamp(3.5rem, 7vw, 6rem);
}
.led {
  margin: 0 0 0.5rem;
  font-size: 0.74rem;
  font-weight: 600;
  letter-spacing: 0.14em;
  text-transform: uppercase;
  color: var(--brass);
}

/* ── Post cards (index) ───────────────────────────────── */

.post-list { display: grid; gap: 0; margin-top: 1rem; }
.post-card {
  display: grid;
  grid-template-columns: 1fr 21rem;
  gap: clamp(1.5rem, 4vw, 3rem);
  align-items: start;
  text-decoration: none;
  color: inherit;
  padding: 2.25rem 0;
  border-top: 1px solid var(--line-paper);
  transition: border-color 0.2s ease;
}
.post-card:last-child { border-bottom: 1px solid var(--line-paper); }
.post-card:hover { border-top-color: var(--copper); }
.post-card-media {
  overflow: hidden;
  border-radius: 4px;
  background: var(--ink-2);
}
.post-card-media img {
  display: block;
  width: 100%;
  aspect-ratio: 3 / 2;
  object-fit: cover;
  transition: transform 0.5s cubic-bezier(0.22, 1, 0.36, 1);
}
.post-card:hover .post-card-media img { transform: scale(1.03); }
.post-card-tags {
  display: flex;
  flex-wrap: wrap;
  align-items: center;
  gap: 0.55rem 0.9rem;
  font-size: 0.76rem;
  font-weight: 600;
  letter-spacing: 0.12em;
  text-transform: uppercase;
  color: var(--brass);
  margin-bottom: 0.9rem;
}
.post-card-tags .muted {
  color: var(--on-paper-mute);
  font-weight: 500;
  letter-spacing: 0.06em;
  opacity: 0.8;
}
.post-card h3 {
  font-family: var(--serif);
  font-size: clamp(1.55rem, 2.6vw, 2.05rem);
  line-height: 1.18;
  color: var(--on-paper);
  max-width: 32ch;
  text-wrap: balance;
}
.post-card p {
  margin: 0.85rem 0 0;
  font-size: 1.04rem;
  line-height: 1.68;
  color: var(--on-paper-mute);
  max-width: 62ch;
}
.post-card .more {
  display: inline-flex;
  align-items: center;
  gap: 0.5rem;
  margin-top: 1.15rem;
  font-size: 0.95rem;
  font-weight: 600;
  color: var(--copper);
}
.post-card .more svg { transition: transform 0.22s ease; }
.post-card:hover .more svg { transform: translateX(3px); }

.post-more {
  margin: 2.5rem 0 0;
  font-size: 0.98rem;
  color: var(--on-paper-mute);
}
.post-more a, .article a {
  color: var(--copper);
  text-decoration: none;
  border-bottom: 1px solid rgba(196, 90, 60, 0.4);
  transition: border-color 0.2s ease;
}
.post-more a:hover, .article a:hover { border-color: var(--copper); }

/* ── Article body ─────────────────────────────────────── */

.article { max-width: 46rem; margin: 0 auto; }

.article p {
  font-size: 1.16rem;
  line-height: 1.8;
  color: var(--on-paper-mute);
  margin: 1.45rem 0 0;
  text-wrap: pretty;
}
.article strong { color: var(--on-paper); font-weight: 600; }
.article em { font-style: italic; }

.article h2, .article h3, .article h4 {
  font-family: var(--serif);
  color: var(--on-paper);
  text-wrap: balance;
}
.article h2 { font-size: clamp(1.6rem, 2.8vw, 2.1rem); line-height: 1.2; margin-top: 3.25rem; }
.article h3 { font-size: clamp(1.35rem, 2.2vw, 1.65rem); line-height: 1.25; margin-top: 2.75rem; }
.article h4 { font-size: 1.2rem; line-height: 1.3; margin-top: 2.25rem; }
.article h2 + p, .article h3 + p, .article h4 + p { margin-top: 1rem; }
.article h2 strong, .article h3 strong, .article h4 strong { font-weight: inherit; }

.article ul, .article ol {
  margin: 1.25rem 0 0;
  padding-left: 1.5rem;
  font-size: 1.12rem;
  line-height: 1.7;
  color: var(--on-paper-mute);
}
.article li { margin-top: 0.5rem; padding-left: 0.25rem; }
.article li > ul, .article li > ol { margin-top: 0.4rem; font-size: 1.04rem; }
.article ol ol { list-style: lower-alpha; }
.article ul { list-style: disc; }
.article li::marker { color: var(--brass); font-weight: 600; }

.article blockquote {
  margin: 2.5rem 0;
  padding-left: 1.5rem;
  border-left: 3px solid var(--copper);
}
.article blockquote p {
  font-family: var(--serif);
  font-size: clamp(1.3rem, 2.2vw, 1.7rem);
  line-height: 1.35;
  color: var(--on-paper);
  margin: 0;
}
.article blockquote p + p { margin-top: 1rem; }

.article hr {
  width: 3.5rem;
  height: 1px;
  background: var(--line-paper);
  border: 0;
  margin: 3rem 0;
}

.article table {
  width: 100%;
  border-collapse: collapse;
  margin: 2rem 0 0;
  font-size: 0.98rem;
  line-height: 1.5;
  color: var(--on-paper-mute);
}
.article td, .article th {
  padding: 0.75rem 0.9rem;
  border: 1px solid var(--line-paper);
  vertical-align: top;
  text-align: left;
}
.article tr:first-child td {
  font-weight: 600;
  color: var(--on-paper);
  background: var(--paper-2);
}
.article .table-scroll { overflow-x: auto; }

.article .artfig { margin: 0 0 2.5rem; }
.article .artfig img {
  display: block;
  width: 100%;
  height: auto;
  max-height: 34rem;
  object-fit: cover;
  border-radius: 4px;
  background: var(--ink-2);
}
.article .artfig figcaption {
  font-size: 0.86rem;
  line-height: 1.6;
  color: var(--on-paper-mute);
  opacity: 0.85;
  margin-top: 0.95rem;
}
.article .artfig--lead { margin-top: -0.5rem; }

/* ── Older / newer ────────────────────────────────────── */

.post-nav {
  max-width: 46rem;
  margin: 3.5rem auto 0;
  padding-top: 2rem;
  border-top: 1px solid var(--line-paper);
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: 2rem;
}
.post-nav-link {
  display: flex;
  flex-direction: column;
  gap: 0.35rem;
  text-decoration: none;
  color: var(--on-paper);
}
.post-nav-link--next { text-align: right; }
.post-nav-k {
  font-size: 0.72rem;
  font-weight: 600;
  letter-spacing: 0.14em;
  text-transform: uppercase;
  color: var(--brass);
}
.post-nav-t {
  font-family: var(--serif);
  font-size: 1.2rem;
  line-height: 1.3;
  transition: color 0.2s ease;
}
.post-nav-link:hover .post-nav-t { color: var(--copper); }

/* ── Footer ───────────────────────────────────────────── */

.footer {
  background: #06080b;
  border-top: 1px solid var(--line-ink-soft);
  padding: 4rem 0 2rem;
}
.footer-top {
  display: grid;
  grid-template-columns: 1.6fr 1fr 1fr;
  gap: 2.5rem;
  padding-bottom: 3rem;
  border-bottom: 1px solid var(--line-ink-soft);
}
.footer-brand img { height: 26px; width: auto; margin-bottom: 1.1rem; }
.footer-brand p {
  margin: 0;
  font-size: 0.95rem;
  line-height: 1.66;
  color: var(--on-ink-mute);
  max-width: 34ch;
}
.footer-col h5 {
  font-size: 0.66rem;
  font-weight: 500;
  letter-spacing: 0.18em;
  text-transform: uppercase;
  color: var(--on-ink-faint);
  margin-bottom: 1.05rem;
}
.footer-col a {
  display: block;
  font-size: 0.95rem;
  color: var(--on-ink-mute);
  text-decoration: none;
  padding: 0.34rem 0;
  transition: color 0.2s ease;
}
.footer-col a:hover { color: var(--on-ink); }
.footer-bot {
  display: flex;
  flex-wrap: wrap;
  align-items: center;
  justify-content: space-between;
  gap: 1rem;
  padding-top: 1.75rem;
  font-size: 0.68rem;
  letter-spacing: 0.1em;
  color: var(--on-ink-faint);
}

/* ── Responsive ───────────────────────────────────────── */

@media (max-width: 900px) {
  .post-card { grid-template-columns: 1fr; }
  .post-card-media { order: -1; max-width: 30rem; }
}
@media (max-width: 720px) {
  .nav-title { display: none; }
  .nav-links { gap: 1.1rem; }
  .footer-top { grid-template-columns: 1fr 1fr; }
  .footer-brand { grid-column: 1 / -1; }
  .post-nav { grid-template-columns: 1fr; }
  .post-nav-link--next { text-align: left; }
}
@media (max-width: 620px) {
  .hero h1 { font-size: 1.75rem; line-height: 1.14; }
  .article p, .article ul, .article ol { font-size: 1.06rem; }
  .article .artfig img { max-height: 22rem; }
}