:root {
  --color-primary: #1a5276;
  --color-primary-light: #2980b9;
  --color-primary-dark: #0e2f44;
  --color-accent: #2eaadc;
  --color-accent-hover: #1f8dbf;
  --color-bg: #ffffff;
  --color-bg-alt: #f8fafb;
  --color-bg-card: #ffffff;
  --color-text: #1e293b;
  --color-text-secondary: #64748b;
  --color-text-muted: #94a3b8;
  --color-border: #e2e8f0;
  --color-border-light: #f1f5f9;
  --radius-sm: 6px;
  --radius-md: 10px;
  --radius-lg: 16px;
  --radius-xl: 24px;
  --shadow-sm: 0 1px 3px rgba(0,0,0,.06);
  --shadow-md: 0 4px 16px rgba(0,0,0,.08);
  --shadow-lg: 0 8px 32px rgba(0,0,0,.1);
  --shadow-card: 0 2px 12px rgba(26,82,118,.06);
  --space-xs: 4px;
  --space-sm: 8px;
  --space-md: 16px;
  --space-lg: 24px;
  --space-xl: 40px;
  --space-2xl: 64px;
  --space-3xl: 96px;
  --space-4xl: 128px;
  --font-heading: 'Noto Serif KR', 'Pretendard Variable', serif;
  --font-body: 'Pretendard Variable', -apple-system, BlinkMacSystemFont, system-ui, sans-serif;
  --max-width: 1200px;
  --content-width: 780px;
  --transition: 200ms ease;
}

*, *::before, *::after { box-sizing: border-box; margin: 0; padding: 0; }

html { font-size: 16px; scroll-behavior: smooth; -webkit-font-smoothing: antialiased; }
@media (prefers-reduced-motion: reduce) { html { scroll-behavior: auto; } * { animation-duration: 0.01ms !important; transition-duration: 0.01ms !important; } }

body {
  font-family: var(--font-body);
  color: var(--color-text);
  background: var(--color-bg);
  line-height: 1.7;
  overflow-x: hidden;
}

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

/* ===== HEADER / NAV ===== */
.site-header {
  position: sticky; top: 0; z-index: 100;
  background: rgba(255,255,255,.92);
  backdrop-filter: blur(16px);
  border-bottom: 1px solid var(--color-border);
  transition: box-shadow var(--transition);
}
.site-header.scrolled { box-shadow: var(--shadow-md); }

.header-inner {
  max-width: var(--max-width);
  margin: 0 auto;
  display: flex; align-items: center; justify-content: space-between;
  padding: 0 var(--space-lg);
  height: 64px;
}

.site-logo { display: flex; align-items: center; gap: 10px; text-decoration: none; color: var(--color-primary-dark); }
.site-logo img { width: 36px; height: 36px; object-fit: contain; border-radius: var(--radius-sm); flex: 0 0 36px; }
.site-logo-text { font-family: var(--font-heading); font-size: 1.05rem; font-weight: 700; letter-spacing: -0.02em; }

.nav-menu { display: flex; gap: var(--space-xs); list-style: none; }
.nav-menu a {
  display: block; padding: 8px 14px;
  font-size: .875rem; font-weight: 500; color: var(--color-text-secondary);
  text-decoration: none; border-radius: var(--radius-sm);
  transition: color var(--transition), background var(--transition);
}
.nav-menu a:hover { color: var(--color-primary); background: var(--color-bg-alt); }

.nav-toggle { display: none; background: none; border: none; padding: 8px; cursor: pointer; }
.nav-toggle svg { width: 24px; height: 24px; stroke: var(--color-text); }

@media (max-width: 768px) {
  .nav-toggle { display: block; }
  .nav-menu {
    display: none; position: absolute; top: 64px; left: 0; right: 0;
    flex-direction: column; background: #fff; border-bottom: 1px solid var(--color-border);
    padding: var(--space-sm) var(--space-lg); box-shadow: var(--shadow-md);
  }
  .nav-menu.open { display: flex; }
  .nav-menu a { padding: 12px 8px; font-size: 1rem; }
}

/* ===== HERO ===== */
.hero {
  position: relative;
  min-height: 520px;
  display: flex; align-items: center; justify-content: center;
  overflow: hidden;
  background: var(--color-primary-dark);
}
.hero-bg {
  position: absolute; inset: 0;
  background-size: cover; background-position: center;
  filter: brightness(.45);
  transition: transform 8s ease;
}
.hero:hover .hero-bg { transform: scale(1.03); }
.hero-overlay {
  position: absolute; inset: 0;
  background: linear-gradient(180deg, rgba(14,47,68,.6) 0%, rgba(26,82,118,.7) 100%);
}
.hero-content {
  position: relative; z-index: 2;
  text-align: center;
  max-width: 680px;
  padding: var(--space-3xl) var(--space-lg);
  color: #fff;
}
.hero-content h1 {
  font-family: var(--font-heading);
  font-size: clamp(2rem, 5vw, 3.2rem);
  font-weight: 700;
  line-height: 1.25;
  letter-spacing: -0.03em;
  margin-bottom: var(--space-md);
}
.hero-subtitle {
  font-size: clamp(1rem, 2.2vw, 1.15rem);
  line-height: 1.7;
  color: rgba(255,255,255,.85);
  margin-bottom: var(--space-xl);
}
.hero-cta {
  display: inline-flex; align-items: center; gap: 8px;
  padding: 14px 32px;
  background: var(--color-accent);
  color: #fff; font-weight: 600; font-size: .95rem;
  text-decoration: none;
  border-radius: 50px;
  transition: background var(--transition), transform var(--transition);
}
.hero-cta:hover { background: var(--color-accent-hover); transform: translateY(-2px); }

/* ===== SECTION ===== */
.section { padding: var(--space-3xl) var(--space-lg); }
.section-alt { background: var(--color-bg-alt); }
.section-inner { max-width: var(--max-width); margin: 0 auto; }

.section-title {
  font-family: var(--font-heading);
  font-size: clamp(1.5rem, 3vw, 2rem);
  font-weight: 700;
  color: var(--color-primary-dark);
  text-align: center;
  margin-bottom: var(--space-sm);
  letter-spacing: -0.02em;
}
.section-desc {
  text-align: center;
  color: var(--color-text-secondary);
  max-width: 560px;
  margin: 0 auto var(--space-2xl);
  line-height: 1.7;
}
.section-line {
  width: 48px; height: 3px;
  background: var(--color-accent);
  margin: var(--space-md) auto var(--space-lg);
  border-radius: 2px;
}

/* ===== CARD GRID ===== */
.card-grid {
  display: grid;
  grid-template-columns: repeat(auto-fill, minmax(340px, 1fr));
  gap: var(--space-lg);
}
@media (max-width: 420px) { .card-grid { grid-template-columns: 1fr; } }

.post-card {
  background: var(--color-bg-card);
  border-radius: var(--radius-lg);
  overflow: hidden;
  box-shadow: var(--shadow-card);
  transition: transform var(--transition), box-shadow var(--transition);
  text-decoration: none; color: inherit; display: block;
}
.post-card:hover { transform: translateY(-4px); box-shadow: var(--shadow-lg); }

.post-card-img {
  position: relative;
  aspect-ratio: 16/10;
  overflow: hidden;
}
.post-card-img img {
  width: 100%; height: 100%;
  object-fit: cover;
  transition: transform .4s ease;
}
.post-card:hover .post-card-img img { transform: scale(1.05); }

.post-card-body { padding: var(--space-lg); }
.post-card-body h3 {
  font-family: var(--font-heading);
  font-size: 1.1rem; font-weight: 700;
  line-height: 1.45;
  margin-bottom: var(--space-sm);
  color: var(--color-primary-dark);
}
.post-card-body p {
  font-size: .9rem; line-height: 1.65;
  color: var(--color-text-secondary);
  display: -webkit-box; -webkit-line-clamp: 3; -webkit-box-orient: vertical; overflow: hidden;
}
.post-card-meta {
  display: flex; align-items: center; gap: var(--space-sm);
  margin-top: var(--space-md);
  font-size: .8rem; color: var(--color-text-muted);
}

/* ===== CAROUSEL ===== */
.carousel-wrap {
  position: relative;
  overflow: hidden;
}
.carousel-track {
  display: flex; gap: var(--space-lg);
  overflow-x: auto;
  scroll-snap-type: x mandatory;
  -webkit-overflow-scrolling: touch;
  scrollbar-width: none;
  padding-bottom: var(--space-sm);
}
.carousel-track::-webkit-scrollbar { display: none; }
.carousel-track .post-card {
  flex: 0 0 340px;
  scroll-snap-align: start;
}
@media (max-width: 420px) { .carousel-track .post-card { flex: 0 0 calc(100vw - 48px); } }

/* ===== FEATURES ===== */
.features-grid {
  display: grid;
  grid-template-columns: repeat(auto-fill, minmax(260px, 1fr));
  gap: var(--space-lg);
}
.feature-card {
  text-align: center;
  padding: var(--space-xl) var(--space-lg);
  background: var(--color-bg-card);
  border-radius: var(--radius-lg);
  border: 1px solid var(--color-border-light);
  transition: border-color var(--transition), box-shadow var(--transition);
}
.feature-card:hover { border-color: var(--color-accent); box-shadow: var(--shadow-md); }
.feature-icon {
  width: 56px; height: 56px;
  margin: 0 auto var(--space-md);
  background: linear-gradient(135deg, var(--color-primary-light), var(--color-accent));
  border-radius: var(--radius-md);
  display: flex; align-items: center; justify-content: center;
}
.feature-icon svg { width: 28px; height: 28px; stroke: #fff; fill: none; stroke-width: 1.8; }
.feature-card h3 { font-size: 1rem; font-weight: 700; margin-bottom: var(--space-sm); color: var(--color-primary-dark); }
.feature-card p { font-size: .875rem; color: var(--color-text-secondary); line-height: 1.65; }

/* ===== FOOTER ===== */
.site-footer {
  background: var(--color-primary-dark);
  color: rgba(255,255,255,.7);
  padding: var(--space-2xl) var(--space-lg) var(--space-xl);
}
.footer-inner {
  max-width: var(--max-width);
  margin: 0 auto;
}
.footer-top {
  display: flex; justify-content: space-between; align-items: flex-start;
  flex-wrap: wrap; gap: var(--space-xl);
  padding-bottom: var(--space-xl);
  border-bottom: 1px solid rgba(255,255,255,.1);
}
.footer-brand { max-width: 360px; }
.footer-logo { display: inline-flex; color: #fff; margin-bottom: var(--space-sm); }
.footer-brand .site-logo-text { color: #fff; font-size: 1.1rem; margin-bottom: var(--space-sm); }
.footer-logo .site-logo-text { margin-bottom: 0; }
.footer-brand p { font-size: .85rem; line-height: 1.65; color: rgba(255,255,255,.55); }
.footer-links h4 { color: #fff; font-size: .85rem; font-weight: 600; margin-bottom: var(--space-md); text-transform: uppercase; letter-spacing: .06em; }
.footer-links a { display: block; font-size: .85rem; color: rgba(255,255,255,.55); text-decoration: none; padding: 4px 0; transition: color var(--transition); }
.footer-links a:hover { color: var(--color-accent); }

.footer-bottom {
  padding-top: var(--space-lg);
  display: flex; justify-content: space-between; flex-wrap: wrap; gap: var(--space-md);
}
.footer-copy { font-size: .8rem; color: rgba(255,255,255,.4); }
.footer-notice { font-size: .78rem; color: rgba(255,255,255,.35); line-height: 1.6; max-width: 800px; }

@media (max-width: 480px) {
  .site-logo img { width: 32px; height: 32px; flex-basis: 32px; }
  .site-logo-text { font-size: .95rem; }
  .footer-logo .site-logo-text { font-size: 1rem; }
}

/* ===== SINGLE POST ===== */
.post-hero { position: relative; min-height: 340px; display: flex; align-items: flex-end; background: var(--color-primary-dark); }
.post-hero-bg { position: absolute; inset: 0; background-size: cover; background-position: center; filter: brightness(.4); }
.post-hero-overlay { position: absolute; inset: 0; background: linear-gradient(to top, rgba(14,47,68,.85) 0%, transparent 60%); }
.post-hero-content { position: relative; z-index: 2; max-width: var(--max-width); margin: 0 auto; padding: var(--space-2xl) var(--space-lg); color: #fff; width: 100%; }
.post-hero-content h1 { font-family: var(--font-heading); font-size: clamp(1.6rem, 4vw, 2.4rem); font-weight: 700; line-height: 1.3; letter-spacing: -0.02em; }
.post-hero-meta { margin-top: var(--space-md); font-size: .875rem; color: rgba(255,255,255,.7); }

.post-body {
  max-width: var(--content-width);
  margin: 0 auto;
  padding: var(--space-2xl) var(--space-lg) var(--space-3xl);
  font-size: 1.05rem;
  line-height: 1.8;
}
.post-body h2 {
  font-family: var(--font-heading);
  font-size: 1.45rem; font-weight: 700;
  color: var(--color-primary-dark);
  margin: var(--space-2xl) 0 var(--space-md);
  padding-bottom: var(--space-sm);
  border-bottom: 2px solid var(--color-accent);
  letter-spacing: -0.01em;
}
.post-body h3 {
  font-family: var(--font-heading);
  font-size: 1.15rem; font-weight: 700;
  color: var(--color-primary);
  margin: var(--space-xl) 0 var(--space-sm);
}
.post-body p { margin-bottom: var(--space-md); color: var(--color-text); }
.post-body img { border-radius: var(--radius-md); margin: var(--space-xl) 0; box-shadow: var(--shadow-sm); }
.post-body ul, .post-body ol { margin: var(--space-md) 0; padding-left: var(--space-lg); }
.post-body li { margin-bottom: var(--space-sm); line-height: 1.7; }
.post-body blockquote {
  border-left: 4px solid var(--color-accent);
  background: var(--color-bg-alt);
  padding: var(--space-lg);
  margin: var(--space-xl) 0;
  border-radius: 0 var(--radius-md) var(--radius-md) 0;
  font-size: .95rem;
  color: var(--color-text-secondary);
}
.post-body table {
  width: 100%;
  border-collapse: separate;
  border-spacing: 0;
  margin: var(--space-xl) 0;
  border-radius: var(--radius-md);
  overflow: hidden;
  box-shadow: var(--shadow-sm);
  font-size: .92rem;
}
.post-body thead th {
  background: var(--color-primary-dark);
  color: #fff;
  font-weight: 600;
  padding: 14px 16px;
  text-align: left;
}
.post-body tbody td {
  padding: 12px 16px;
  border-bottom: 1px solid var(--color-border);
}
.post-body tbody tr:last-child td { border-bottom: none; }
.post-body tbody tr:nth-child(even) { background: var(--color-bg-alt); }
.post-body .callout-box {
  background: linear-gradient(135deg, #eff6ff, #f0f9ff);
  border: 1px solid #bfdbfe;
  border-radius: var(--radius-md);
  padding: var(--space-lg);
  margin: var(--space-xl) 0;
}
.post-body .callout-box strong { color: var(--color-primary); }
.post-body .legal-notice { font-size: .85em; }
.post-body .ai-notice { font-size: .85em; }

/* Table responsive */
.table-wrap { overflow-x: auto; -webkit-overflow-scrolling: touch; margin: var(--space-xl) 0; }
.table-wrap table { margin: 0; }

/* Related posts */
.related-posts { max-width: var(--max-width); margin: 0 auto; padding: 0 var(--space-lg) var(--space-3xl); }
.related-posts h2 { font-family: var(--font-heading); font-size: 1.3rem; margin-bottom: var(--space-lg); color: var(--color-primary-dark); }

/* TOC */
.toc-box {
  background: var(--color-bg-alt);
  border: 1px solid var(--color-border);
  border-radius: var(--radius-md);
  padding: var(--space-lg);
  margin-bottom: var(--space-2xl);
}
.toc-box h4 { font-size: .95rem; font-weight: 700; margin-bottom: var(--space-sm); color: var(--color-primary-dark); }
.toc-box ol { padding-left: var(--space-lg); }
.toc-box li { margin-bottom: 6px; }
.toc-box a { font-size: .9rem; color: var(--color-text-secondary); text-decoration: none; transition: color var(--transition); }
.toc-box a:hover { color: var(--color-accent); }

/* PAGE */
.page-body { max-width: var(--content-width); margin: 0 auto; padding: var(--space-2xl) var(--space-lg) var(--space-3xl); }
.page-body h1 { font-family: var(--font-heading); font-size: 1.8rem; margin-bottom: var(--space-xl); color: var(--color-primary-dark); }
.page-body h2 { font-family: var(--font-heading); font-size: 1.3rem; margin: var(--space-xl) 0 var(--space-md); color: var(--color-primary-dark); }
.page-body p { margin-bottom: var(--space-md); line-height: 1.7; }
.page-body ul, .page-body ol { margin: var(--space-md) 0; padding-left: var(--space-lg); }
.page-body li { margin-bottom: var(--space-sm); }

/* Scroll animation */
.fade-up { opacity: 0; transform: translateY(24px); transition: opacity .5s ease, transform .5s ease; }
.fade-up.visible { opacity: 1; transform: translateY(0); }

/* Focus ring */
a:focus-visible, button:focus-visible { outline: 2px solid var(--color-accent); outline-offset: 2px; border-radius: 2px; }

/* Print */
@media print { .site-header, .site-footer, .nav-toggle { display: none; } }