/* Research Booth — Custom Stylesheet */
/* Design: Warm editorial, amber/teal palette, serif headings with clean sans body */

:root {
  --primary: #1a5276;
  --primary-dark: #154360;
  --primary-light: #2471a3;
  --accent: #ca6f1e;
  --accent-light: #e67e22;
  --bg: #fdfcf9;
  --bg-alt: #f2ede4;
  --bg-card: #ffffff;
  --text: #2c3e50;
  --text-light: #5d6d7e;
  --text-muted: #85929e;
  --border: #d5cfc4;
  --shadow: 0 2px 12px rgba(26,82,118,0.08);
  --shadow-hover: 0 6px 24px rgba(26,82,118,0.14);
  --radius: 10px;
  --radius-sm: 6px;
  --max-width: 1200px;
}

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

html { scroll-behavior: smooth; }

body {
  font-family: 'Source Serif 4', Georgia, serif;
  color: var(--text);
  background: var(--bg);
  margin: 0;
  line-height: 1.75;
  font-size: 17px;
}

/* ─── Utility ─── */
.container {
  max-width: var(--max-width);
  margin: 0 auto;
  padding: 0 24px;
}
.sr-only { position:absolute; width:1px; height:1px; overflow:hidden; clip:rect(0,0,0,0); }
img { max-width: 100%; height: auto; display: block; }

/* ─── Navigation ─── */
#site-header {
  background: var(--primary-dark);
  position: sticky;
  top: 0;
  z-index: 1000;
  box-shadow: 0 2px 8px rgba(0,0,0,0.2);
}

.nav-inner {
  display: flex;
  align-items: center;
  justify-content: space-between;
  height: 64px;
  gap: 24px;
}

.site-logo {
  display: flex;
  align-items: center;
  gap: 10px;
  text-decoration: none;
  flex-shrink: 0;
}

.logo-icon {
  width: 36px;
  height: 36px;
  background: var(--accent);
  border-radius: 8px;
  display: flex;
  align-items: center;
  justify-content: center;
  font-family: 'Source Serif 4', Georgia, serif;
  font-weight: 700;
  font-size: 20px;
  color: white;
}

.logo-text {
  font-family: 'Source Serif 4', Georgia, serif;
  font-weight: 700;
  font-size: 20px;
  color: white;
  letter-spacing: -0.02em;
}

.main-nav {
  display: flex;
  align-items: center;
  gap: 4px;
  list-style: none;
  margin: 0;
  padding: 0;
}

.main-nav a {
  color: rgba(255,255,255,0.85);
  text-decoration: none;
  padding: 6px 14px;
  border-radius: var(--radius-sm);
  font-size: 14px;
  font-family: 'Inter', sans-serif;
  font-weight: 500;
  transition: all 0.2s;
  letter-spacing: 0.01em;
}

.main-nav a:hover {
  color: white;
  background: rgba(255,255,255,0.12);
}

.nav-toggle {
  display: none;
  background: none;
  border: none;
  cursor: pointer;
  padding: 8px;
  color: white;
}

/* ─── Hero ─── */
.hero {
  position: relative;
  overflow: hidden;
  min-height: 440px;
  display: flex;
  align-items: center;
}

.hero-image {
  position: absolute;
  inset: 0;
  width: 100%;
  height: 100%;
  object-fit: cover;
  object-position: center;
}

.hero-overlay {
  position: absolute;
  inset: 0;
  background: linear-gradient(105deg, rgba(21,67,96,0.90) 0%, rgba(21,67,96,0.65) 55%, rgba(21,67,96,0.3) 100%);
}

.hero-content {
  position: relative;
  z-index: 2;
  padding: 80px 0;
}

.hero-tag {
  display: inline-block;
  background: var(--accent);
  color: white;
  font-family: 'Inter', sans-serif;
  font-size: 12px;
  font-weight: 600;
  letter-spacing: 0.1em;
  text-transform: uppercase;
  padding: 4px 12px;
  border-radius: 100px;
  margin-bottom: 20px;
}

.hero h1 {
  font-family: 'Source Serif 4', Georgia, serif;
  font-size: clamp(2rem, 5vw, 3.2rem);
  font-weight: 700;
  color: white;
  margin: 0 0 20px;
  line-height: 1.2;
  max-width: 680px;
}

.hero-subtitle {
  font-size: 18px;
  color: rgba(255,255,255,0.88);
  max-width: 560px;
  margin: 0 0 32px;
  font-family: 'Inter', sans-serif;
  line-height: 1.6;
}

.hero-cta {
  display: inline-flex;
  align-items: center;
  gap: 8px;
  background: var(--accent);
  color: white;
  text-decoration: none;
  padding: 12px 24px;
  border-radius: var(--radius);
  font-family: 'Inter', sans-serif;
  font-weight: 600;
  font-size: 15px;
  transition: all 0.2s;
  box-shadow: 0 4px 16px rgba(202,111,30,0.35);
}

.hero-cta:hover {
  background: var(--accent-light);
  transform: translateY(-1px);
  box-shadow: 0 6px 20px rgba(202,111,30,0.45);
}

/* ─── Page Hero (inner pages) ─── */
.page-hero {
  background: linear-gradient(135deg, var(--primary-dark) 0%, var(--primary) 100%);
  padding: 52px 0 44px;
  color: white;
}

.page-hero .breadcrumb {
  font-family: 'Inter', sans-serif;
  font-size: 13px;
  color: rgba(255,255,255,0.65);
  margin-bottom: 12px;
  display: flex;
  gap: 6px;
  align-items: center;
  flex-wrap: wrap;
}

.page-hero .breadcrumb a { color: rgba(255,255,255,0.75); text-decoration: none; }
.page-hero .breadcrumb a:hover { color: white; }
.page-hero .breadcrumb span { opacity: 0.5; }

.page-hero h1 {
  font-family: 'Source Serif 4', Georgia, serif;
  font-size: clamp(1.6rem, 4vw, 2.6rem);
  font-weight: 700;
  margin: 0 0 12px;
  color: white;
  line-height: 1.25;
}

.page-hero .lead {
  font-size: 17px;
  color: rgba(255,255,255,0.82);
  max-width: 600px;
  font-family: 'Inter', sans-serif;
  margin: 0;
}

/* ─── Main Content ─── */
.content-wrap {
  padding: 56px 0 80px;
}

.content-grid {
  display: grid;
  grid-template-columns: 1fr 300px;
  gap: 48px;
  align-items: start;
}

.article-body {
  min-width: 0;
}

.article-body h1 {
  font-family: 'Source Serif 4', Georgia, serif;
  font-size: 2.2rem;
  color: var(--primary-dark);
  margin: 0 0 24px;
  line-height: 1.25;
}

.article-body h2 {
  font-family: 'Source Serif 4', Georgia, serif;
  font-size: 1.5rem;
  color: var(--primary);
  margin: 44px 0 16px;
  padding-bottom: 8px;
  border-bottom: 2px solid var(--bg-alt);
  line-height: 1.3;
}

.article-body h3 {
  font-family: 'Source Serif 4', Georgia, serif;
  font-size: 1.2rem;
  color: var(--text);
  margin: 28px 0 12px;
}

.article-body p {
  margin: 0 0 20px;
  color: var(--text);
}

.article-body ul, .article-body ol {
  margin: 0 0 20px 24px;
  padding: 0;
}

.article-body li { margin-bottom: 8px; }

.article-body a {
  color: var(--primary-light);
  text-decoration: underline;
  text-underline-offset: 3px;
  transition: color 0.15s;
}

.article-body a:hover { color: var(--primary-dark); }

.article-body strong { color: var(--text); font-weight: 600; }

.article-image {
  border-radius: var(--radius);
  margin: 32px 0;
  box-shadow: var(--shadow);
  width: 100%;
}

/* ─── Category Grid (homepage) ─── */
.category-grid {
  display: grid;
  grid-template-columns: repeat(3, 1fr);
  gap: 24px;
  margin: 32px 0;
}

.category-card {
  background: var(--bg-card);
  border: 1px solid var(--border);
  border-radius: var(--radius);
  padding: 28px 24px;
  box-shadow: var(--shadow);
  transition: box-shadow 0.2s, transform 0.2s;
}

.category-card:hover {
  box-shadow: var(--shadow-hover);
  transform: translateY(-2px);
}

.category-card h3 {
  font-family: 'Source Serif 4', Georgia, serif;
  font-size: 1.15rem;
  color: var(--primary-dark);
  margin: 0 0 12px;
}

.category-card p {
  font-size: 15px;
  color: var(--text-light);
  margin: 0 0 16px;
  line-height: 1.6;
  font-family: 'Inter', sans-serif;
}

.category-card a {
  color: var(--accent);
  text-decoration: none;
  font-family: 'Inter', sans-serif;
  font-weight: 600;
  font-size: 14px;
  display: inline-flex;
  align-items: center;
  gap: 4px;
}

.category-card a:hover { color: var(--accent-light); text-decoration: underline; }

/* ─── Featured Articles List ─── */
.featured-list {
  background: var(--bg-card);
  border: 1px solid var(--border);
  border-radius: var(--radius);
  padding: 28px;
  margin: 32px 0;
}

.featured-list h2 {
  font-family: 'Source Serif 4', Georgia, serif;
  font-size: 1.35rem;
  color: var(--primary-dark);
  margin: 0 0 20px;
  padding-bottom: 12px;
  border-bottom: 2px solid var(--bg-alt);
}

.featured-list ul {
  list-style: none;
  margin: 0;
  padding: 0;
}

.featured-list li {
  padding: 10px 0;
  border-bottom: 1px solid var(--bg-alt);
}

.featured-list li:last-child { border-bottom: none; }

.featured-list a {
  color: var(--primary-light);
  text-decoration: none;
  font-size: 15px;
}

.featured-list a:hover { color: var(--primary-dark); text-decoration: underline; }

/* ─── Sidebar ─── */
.sidebar {
  position: sticky;
  top: 84px;
}

.sidebar-card {
  background: var(--bg-card);
  border: 1px solid var(--border);
  border-radius: var(--radius);
  padding: 24px;
  margin-bottom: 24px;
  box-shadow: var(--shadow);
}

.sidebar-card h3 {
  font-family: 'Source Serif 4', Georgia, serif;
  font-size: 1rem;
  color: var(--primary-dark);
  margin: 0 0 16px;
  padding-bottom: 10px;
  border-bottom: 2px solid var(--bg-alt);
  text-transform: uppercase;
  letter-spacing: 0.04em;
  font-size: 13px;
}

.sidebar-card ul {
  list-style: none;
  margin: 0;
  padding: 0;
}

.sidebar-card li {
  padding: 6px 0;
  border-bottom: 1px solid var(--bg-alt);
  font-size: 14px;
}

.sidebar-card li:last-child { border-bottom: none; }

.sidebar-card a {
  color: var(--text-light);
  text-decoration: none;
  font-family: 'Inter', sans-serif;
  display: flex;
  align-items: center;
  gap: 6px;
}

.sidebar-card a:hover { color: var(--primary); }
.sidebar-card a::before { content: "›"; color: var(--accent); font-weight: 700; }

/* ─── Article List (category indexes) ─── */
.article-list {
  list-style: none;
  margin: 0;
  padding: 0;
}

.article-list li {
  padding: 16px 0;
  border-bottom: 1px solid var(--border);
}

.article-list li:last-child { border-bottom: none; }

.article-list a {
  font-family: 'Source Serif 4', Georgia, serif;
  font-size: 1.05rem;
  color: var(--primary-light);
  text-decoration: none;
  display: block;
  margin-bottom: 4px;
}

.article-list a:hover { color: var(--primary-dark); }

.article-list .description {
  font-size: 14px;
  color: var(--text-muted);
  font-family: 'Inter', sans-serif;
  margin: 0;
}

/* ─── Info Box ─── */
.info-box {
  background: #eaf2f8;
  border-left: 4px solid var(--primary-light);
  border-radius: 0 var(--radius-sm) var(--radius-sm) 0;
  padding: 16px 20px;
  margin: 28px 0;
}

.info-box p {
  margin: 0;
  font-size: 15px;
  color: var(--primary-dark);
  font-family: 'Inter', sans-serif;
}

/* ─── Sections (homepage) ─── */
.section { padding: 64px 0; }
.section-alt { background: var(--bg-alt); }

.section-header {
  text-align: center;
  margin-bottom: 44px;
}

.section-header h2 {
  font-family: 'Source Serif 4', Georgia, serif;
  font-size: 2rem;
  color: var(--primary-dark);
  margin: 0 0 12px;
}

.section-header p {
  font-size: 17px;
  color: var(--text-light);
  max-width: 560px;
  margin: 0 auto;
  font-family: 'Inter', sans-serif;
}

/* ─── Footer ─── */
#site-footer {
  background: var(--primary-dark);
  color: rgba(255,255,255,0.75);
  padding: 48px 0 24px;
}

.footer-grid {
  display: grid;
  grid-template-columns: 2fr 1fr 1fr;
  gap: 40px;
  padding-bottom: 36px;
  border-bottom: 1px solid rgba(255,255,255,0.1);
}

.footer-brand .logo-text {
  font-size: 22px;
  margin-bottom: 12px;
  display: block;
}

.footer-brand p {
  font-size: 14px;
  line-height: 1.6;
  max-width: 280px;
  font-family: 'Inter', sans-serif;
}

.footer-col h4 {
  color: white;
  font-family: 'Inter', sans-serif;
  font-weight: 600;
  font-size: 13px;
  letter-spacing: 0.08em;
  text-transform: uppercase;
  margin: 0 0 16px;
}

.footer-col ul {
  list-style: none;
  margin: 0;
  padding: 0;
}

.footer-col li { margin-bottom: 8px; }

.footer-col a {
  color: rgba(255,255,255,0.65);
  text-decoration: none;
  font-size: 14px;
  font-family: 'Inter', sans-serif;
  transition: color 0.15s;
}

.footer-col a:hover { color: white; }

.footer-bottom {
  display: flex;
  justify-content: space-between;
  align-items: center;
  padding-top: 24px;
  gap: 16px;
  flex-wrap: wrap;
}

.footer-copy {
  font-size: 13px;
  font-family: 'Inter', sans-serif;
}

/* ─── 404 Page ─── */
.not-found {
  min-height: 60vh;
  display: flex;
  align-items: center;
  justify-content: center;
  text-align: center;
  padding: 80px 24px;
}

.not-found h1 {
  font-family: 'Source Serif 4', Georgia, serif;
  font-size: 6rem;
  color: var(--bg-alt);
  margin: 0 0 16px;
  line-height: 1;
}

.not-found h2 {
  font-family: 'Source Serif 4', Georgia, serif;
  font-size: 1.8rem;
  color: var(--primary-dark);
  margin: 0 0 16px;
}

.not-found p {
  color: var(--text-light);
  font-family: 'Inter', sans-serif;
  max-width: 400px;
  margin: 0 auto 28px;
}

.btn-primary {
  display: inline-flex;
  align-items: center;
  gap: 8px;
  background: var(--primary);
  color: white;
  text-decoration: none;
  padding: 12px 24px;
  border-radius: var(--radius);
  font-family: 'Inter', sans-serif;
  font-weight: 600;
  font-size: 15px;
  transition: all 0.2s;
}

.btn-primary:hover { background: var(--primary-dark); transform: translateY(-1px); }

/* ─── Responsive ─── */
@media (max-width: 900px) {
  .content-grid { grid-template-columns: 1fr; }
  .sidebar { position: static; }
  .category-grid { grid-template-columns: repeat(2, 1fr); }
  .footer-grid { grid-template-columns: 1fr 1fr; }
  .footer-brand { grid-column: 1 / -1; }
}

@media (max-width: 640px) {
  .main-nav { display: none; }
  .nav-toggle { display: flex; }
  .main-nav.open {
    display: flex;
    flex-direction: column;
    position: absolute;
    top: 64px;
    left: 0;
    right: 0;
    background: var(--primary-dark);
    padding: 16px;
    gap: 4px;
    z-index: 999;
  }
  .category-grid { grid-template-columns: 1fr; }
  .footer-grid { grid-template-columns: 1fr; }
  .hero { min-height: 360px; }
}