/* ============================================
   Strategic Reasoning Lab — Shared Stylesheet
   Economist-inspired: Merriweather + Inter + gold accent
   ============================================ */

:root {
  --black: #1D1D1B;
  --near-black: #121212;
  --navy: #1A2744;
  --navy-dark: #0F1930;
  --gold: #B8860B;
  --gold-dark: #9A7209;
  --gold-light: #D4A843;
  --gold-pale: #F5EDD8;
  --gold-wash: #FBF7EB;
  --white: #FFFFFF;
  --off-white: #F9F9F7;
  --cream: #FAF8F3;
  --text: #1D1D1B;
  --text-secondary: #5C5C5C;
  --text-light: #8A8A8A;
  --rule: #DCDCDC;
  --rule-dark: #C0C0C0;
  --rule-light: #ECECEC;
  --bg-tint: #F4F3F0;
  --font-serif: 'Merriweather', Georgia, 'Times New Roman', serif;
  --font-sans: 'Inter', -apple-system, 'Segoe UI', Helvetica, Arial, sans-serif;
}

* { margin: 0; padding: 0; box-sizing: border-box; }
html { font-size: 16px; scroll-behavior: smooth; }
body {
  font-family: var(--font-serif);
  color: var(--text);
  background: var(--white);
  line-height: 1.7;
  -webkit-font-smoothing: antialiased;
}

a { color: var(--gold-dark); text-decoration: none; }
a:hover { text-decoration: underline; }

/* ====== TOP NAV RIBBON ====== */
.nav-top {
  background: var(--near-black);
  padding: 0.4rem 2.5rem;
  display: flex;
  justify-content: flex-end;
  gap: 1.75rem;
}
.nav-top a {
  font-family: var(--font-sans);
  font-size: 0.7rem;
  font-weight: 500;
  color: rgba(255,255,255,0.55);
  text-decoration: none;
  letter-spacing: 0.03em;
}
.nav-top a:hover { color: rgba(255,255,255,0.9); text-decoration: none; }

/* ====== MAIN NAV ====== */
.nav-main {
  background: var(--white);
  border-bottom: 3px solid var(--gold);
  position: sticky;
  top: 0;
  z-index: 100;
}
.nav-main-inner {
  max-width: 1180px;
  margin: 0 auto;
  display: flex;
  justify-content: space-between;
  align-items: center;
  padding: 1.2rem 2rem;
}
.logo-block { line-height: 1.05; }
.logo {
  font-family: var(--font-serif);
  font-size: 1.55rem;
  font-weight: 900;
  color: var(--black);
  letter-spacing: -0.02em;
  text-decoration: none;
}
.logo:hover { text-decoration: none; }
.logo-sub {
  font-family: var(--font-sans);
  font-size: 0.62rem;
  font-weight: 600;
  color: var(--text-light);
  letter-spacing: 0.14em;
  text-transform: uppercase;
  margin-top: 0.3rem;
  display: block;
}

.nav-links {
  display: flex;
  gap: 1.8rem;
  align-items: center;
}
.nav-links a {
  font-family: var(--font-sans);
  font-size: 0.82rem;
  font-weight: 500;
  color: var(--text);
  text-decoration: none;
  letter-spacing: 0.01em;
  padding: 0.4rem 0;
  border-bottom: 2px solid transparent;
  transition: border-color 0.2s;
}
.nav-links a:hover {
  color: var(--gold-dark);
  border-bottom-color: var(--gold);
  text-decoration: none;
}
.nav-links a.active {
  color: var(--gold-dark);
  border-bottom-color: var(--gold);
}
.nav-links a.nav-cta {
  background: var(--black);
  color: var(--white);
  padding: 0.55rem 1.1rem;
  border: none;
  font-weight: 600;
  font-size: 0.75rem;
  letter-spacing: 0.05em;
  text-transform: uppercase;
}
.nav-links a.nav-cta:hover {
  background: var(--gold-dark);
  border: none;
}

/* ====== PAGE HEADER (non-home pages) ====== */
.page-header {
  background: var(--cream);
  border-bottom: 1px solid var(--rule);
  padding: 4rem 2rem 3rem;
}
.page-header-inner {
  max-width: 980px;
  margin: 0 auto;
}
.page-header .kicker {
  font-family: var(--font-sans);
  font-size: 0.72rem;
  font-weight: 700;
  color: var(--gold-dark);
  letter-spacing: 0.2em;
  text-transform: uppercase;
  margin-bottom: 1rem;
}
.page-header h1 {
  font-family: var(--font-serif);
  font-weight: 900;
  font-size: 2.8rem;
  line-height: 1.1;
  color: var(--black);
  letter-spacing: -0.02em;
  margin-bottom: 1rem;
}
.page-header h1 em {
  font-style: italic;
  color: var(--gold-dark);
  font-weight: 700;
}
.page-header .lead {
  font-family: var(--font-serif);
  font-size: 1.15rem;
  font-weight: 300;
  line-height: 1.6;
  color: var(--text-secondary);
  max-width: 720px;
  font-style: italic;
}

/* ====== HOME HERO ====== */
.hero {
  background: var(--white);
  padding: 4.5rem 2rem 4rem;
  border-bottom: 1px solid var(--rule);
}
.hero-inner {
  max-width: 1180px;
  margin: 0 auto;
  display: grid;
  grid-template-columns: 1.5fr 1fr;
  gap: 4rem;
  align-items: start;
}
.hero-kicker {
  font-family: var(--font-sans);
  font-size: 0.72rem;
  font-weight: 700;
  color: var(--gold-dark);
  letter-spacing: 0.22em;
  text-transform: uppercase;
  margin-bottom: 1.25rem;
  padding-bottom: 0.75rem;
  border-bottom: 1px solid var(--rule);
}
.hero h1 {
  font-family: var(--font-serif);
  font-weight: 900;
  font-size: 3.2rem;
  line-height: 1.05;
  color: var(--black);
  letter-spacing: -0.025em;
  margin-bottom: 1.5rem;
}
.hero h1 em {
  font-style: italic;
  color: var(--gold-dark);
  font-weight: 700;
}
.hero .lead {
  font-family: var(--font-serif);
  font-size: 1.22rem;
  font-weight: 300;
  line-height: 1.55;
  color: var(--text-secondary);
  margin-bottom: 1.75rem;
  font-style: italic;
}
.hero-aside {
  border-left: 3px solid var(--gold);
  padding: 0.5rem 0 0.5rem 1.75rem;
  margin-top: 3.5rem;
}
.hero-aside-label {
  font-family: var(--font-sans);
  font-size: 0.65rem;
  font-weight: 700;
  color: var(--gold-dark);
  text-transform: uppercase;
  letter-spacing: 0.18em;
  margin-bottom: 0.75rem;
}
.hero-aside p {
  font-family: var(--font-serif);
  font-size: 0.92rem;
  line-height: 1.7;
  color: var(--text-secondary);
  font-style: italic;
}

/* ====== CALLOUT BAR ====== */
.callout-bar {
  background: var(--navy);
  padding: 2.5rem 2rem;
}
.callout-bar-inner {
  max-width: 900px;
  margin: 0 auto;
  text-align: center;
}
.callout-bar p {
  font-family: var(--font-serif);
  font-size: 1.4rem;
  font-weight: 300;
  line-height: 1.55;
  color: rgba(255,255,255,0.92);
  font-style: italic;
}
.callout-bar p em {
  color: var(--gold-light);
  font-style: italic;
  font-weight: 400;
}

/* ====== SECTIONS ====== */
.section {
  padding: 4.5rem 2rem;
  background: var(--white);
}
.section.tinted { background: var(--cream); }
.section.dark { background: var(--near-black); color: rgba(255,255,255,0.85); }
.section.dark h2, .section.dark h3 { color: var(--white); }
.section.dark .section-label { color: var(--gold-light); }
.section.dark p { color: rgba(255,255,255,0.75); }

.section-inner {
  max-width: 1140px;
  margin: 0 auto;
}
.section-inner.narrow {
  max-width: 820px;
}

.section-label {
  font-family: var(--font-sans);
  font-size: 0.72rem;
  font-weight: 700;
  color: var(--gold-dark);
  letter-spacing: 0.2em;
  text-transform: uppercase;
  margin-bottom: 1.25rem;
  padding-bottom: 0.75rem;
  border-bottom: 1px solid var(--rule);
}

h2 {
  font-family: var(--font-serif);
  font-weight: 900;
  font-size: 2.1rem;
  line-height: 1.15;
  color: var(--black);
  letter-spacing: -0.02em;
  margin-bottom: 1.25rem;
}
h2 em {
  font-style: italic;
  color: var(--gold-dark);
  font-weight: 700;
}

h3 {
  font-family: var(--font-serif);
  font-weight: 700;
  font-size: 1.3rem;
  line-height: 1.25;
  color: var(--black);
  margin-bottom: 0.75rem;
}
h3 em { font-style: italic; color: var(--gold-dark); }

h4 {
  font-family: var(--font-sans);
  font-size: 0.72rem;
  font-weight: 700;
  color: var(--gold-dark);
  letter-spacing: 0.16em;
  text-transform: uppercase;
  margin-bottom: 0.75rem;
}

p {
  font-family: var(--font-serif);
  font-size: 1rem;
  line-height: 1.75;
  color: var(--text);
  margin-bottom: 1.1rem;
  font-weight: 300;
}

p.lead {
  font-size: 1.15rem;
  font-style: italic;
  color: var(--text-secondary);
  margin-bottom: 1.5rem;
}

/* ====== PRODUCT CARDS ====== */
.product-grid {
  display: grid;
  grid-template-columns: repeat(2, 1fr);
  gap: 2rem;
  margin-top: 2rem;
}
.product-card {
  background: var(--white);
  border: 1px solid var(--rule);
  border-top: 3px solid var(--gold);
  padding: 2rem 1.75rem 1.75rem;
  display: flex;
  flex-direction: column;
}
.product-card .product-kicker {
  font-family: var(--font-sans);
  font-size: 0.65rem;
  font-weight: 700;
  color: var(--gold-dark);
  letter-spacing: 0.16em;
  text-transform: uppercase;
  margin-bottom: 0.75rem;
}
.product-card h3 {
  font-family: var(--font-serif);
  font-weight: 900;
  font-size: 1.45rem;
  line-height: 1.15;
  margin-bottom: 0.6rem;
}
.product-card .product-sub {
  font-family: var(--font-serif);
  font-style: italic;
  font-size: 0.9rem;
  color: var(--text-light);
  margin-bottom: 1rem;
}
.product-card p {
  font-size: 0.92rem;
  line-height: 1.65;
  margin-bottom: 1.25rem;
}
.product-card .unit {
  font-family: var(--font-sans);
  font-size: 0.68rem;
  font-weight: 600;
  color: var(--text-light);
  letter-spacing: 0.1em;
  text-transform: uppercase;
  margin-top: auto;
  padding-top: 1rem;
  border-top: 1px solid var(--rule-light);
}
.product-card .unit span {
  color: var(--gold-dark);
}
.product-card.flagship {
  background: var(--gold-wash);
  border-top: 3px solid var(--gold-dark);
  border-left: 1px solid var(--gold-pale);
  border-right: 1px solid var(--gold-pale);
  border-bottom: 1px solid var(--gold-pale);
}
.product-card.flagship h3 { color: var(--gold-dark); }

/* ====== CONTENT BLOCKS ====== */
.two-col {
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: 3rem;
  margin-top: 2rem;
}
.three-col {
  display: grid;
  grid-template-columns: repeat(3, 1fr);
  gap: 2.25rem;
  margin-top: 2rem;
}
.four-col {
  display: grid;
  grid-template-columns: repeat(4, 1fr);
  gap: 1.5rem;
  margin-top: 2rem;
}

.pillar {
  padding: 1.5rem 1.25rem;
  border-left: 3px solid var(--gold);
  background: var(--off-white);
}
.pillar h4 { margin-bottom: 0.5rem; }
.pillar h3 { font-size: 1.1rem; margin-bottom: 0.5rem; }
.pillar p { font-size: 0.88rem; line-height: 1.65; margin-bottom: 0; }

.pull-quote {
  border-top: 3px solid var(--gold);
  border-bottom: 1px solid var(--rule);
  padding: 1.5rem 0;
  margin: 2rem 0;
}
.pull-quote p {
  font-family: var(--font-serif);
  font-size: 1.35rem;
  font-weight: 300;
  font-style: italic;
  line-height: 1.5;
  color: var(--black);
  margin-bottom: 0;
}

.byline {
  font-family: var(--font-sans);
  font-size: 0.68rem;
  font-weight: 600;
  color: var(--gold-dark);
  letter-spacing: 0.14em;
  text-transform: uppercase;
  margin-top: 0.75rem;
}

/* ====== CTA ====== */
.btn {
  display: inline-block;
  padding: 0.9rem 1.6rem;
  background: var(--black);
  color: var(--white);
  font-family: var(--font-sans);
  font-size: 0.78rem;
  font-weight: 600;
  letter-spacing: 0.08em;
  text-transform: uppercase;
  text-decoration: none;
  border: none;
  transition: background 0.2s;
}
.btn:hover { background: var(--gold-dark); text-decoration: none; }
.btn.secondary {
  background: transparent;
  color: var(--black);
  border: 1.5px solid var(--black);
}
.btn.secondary:hover {
  background: var(--black);
  color: var(--white);
}

/* ====== TIMELINE ====== */
.timeline {
  display: grid;
  grid-template-columns: repeat(4, 1fr);
  gap: 1.5rem;
  margin-top: 2.5rem;
  position: relative;
}
.timeline-step {
  position: relative;
  padding-top: 2rem;
}
.timeline-step::before {
  content: "";
  position: absolute;
  top: 0;
  left: 0;
  right: 0;
  height: 2px;
  background: var(--gold);
}
.timeline-step .step-num {
  font-family: var(--font-serif);
  font-style: italic;
  font-size: 1rem;
  color: var(--gold-dark);
  margin-bottom: 0.5rem;
}
.timeline-step h4 {
  font-family: var(--font-serif);
  font-size: 1.05rem;
  font-weight: 700;
  color: var(--black);
  text-transform: none;
  letter-spacing: -0.01em;
  margin-bottom: 0.5rem;
}
.timeline-step p {
  font-size: 0.87rem;
  line-height: 1.6;
  color: var(--text-secondary);
  margin-bottom: 0;
}

/* ====== FOOTER ====== */
footer {
  background: var(--near-black);
  padding: 3.5rem 2rem 2rem;
}
.footer-inner {
  max-width: 1180px;
  margin: 0 auto;
}
.footer-top {
  display: grid;
  grid-template-columns: 2fr 1fr 1fr 1fr;
  gap: 3rem;
  padding-bottom: 2.5rem;
  border-bottom: 1px solid rgba(255,255,255,0.1);
}
.footer-brand .logo { color: var(--white); font-size: 1.25rem; }
.footer-brand .logo-sub { color: rgba(255,255,255,0.4); }
.footer-brand p {
  font-family: var(--font-serif);
  font-size: 0.85rem;
  line-height: 1.6;
  color: rgba(255,255,255,0.55);
  font-style: italic;
  margin-top: 1rem;
  max-width: 360px;
}
.footer-col h5 {
  font-family: var(--font-sans);
  font-size: 0.65rem;
  font-weight: 700;
  color: var(--gold-light);
  letter-spacing: 0.18em;
  text-transform: uppercase;
  margin-bottom: 1rem;
}
.footer-col ul {
  list-style: none;
}
.footer-col ul li {
  margin-bottom: 0.6rem;
}
.footer-col a {
  font-family: var(--font-sans);
  font-size: 0.8rem;
  color: rgba(255,255,255,0.55);
  text-decoration: none;
}
.footer-col a:hover {
  color: rgba(255,255,255,0.9);
  text-decoration: none;
}
.footer-bottom {
  padding-top: 1.5rem;
  display: flex;
  justify-content: space-between;
  align-items: center;
}
.footer-bottom p {
  font-family: var(--font-sans);
  font-size: 0.72rem;
  color: rgba(255,255,255,0.35);
  margin-bottom: 0;
}

/* ====== RESPONSIVE ====== */
@media (max-width: 900px) {
  .hero-inner, .two-col, .three-col { grid-template-columns: 1fr; }
  .four-col, .product-grid { grid-template-columns: 1fr 1fr; gap: 1.5rem; }
  .timeline { grid-template-columns: 1fr 1fr; }
  .hero h1 { font-size: 2.3rem; }
  .page-header h1 { font-size: 2rem; }
  h2 { font-size: 1.7rem; }
  .footer-top { grid-template-columns: 1fr 1fr; gap: 2rem; }
  .nav-top { display: none; }
  .nav-links { gap: 1rem; }
  .nav-links a:not(.nav-cta) { font-size: 0.7rem; }
}
@media (max-width: 600px) {
  .four-col, .product-grid, .footer-top { grid-template-columns: 1fr; }
  .timeline { grid-template-columns: 1fr; }
  .section { padding: 3rem 1.25rem; }
  .nav-main-inner { padding: 1rem 1.25rem; }
  .logo { font-size: 1.25rem; }
  .nav-links { gap: 0.75rem; }
}