:root {
  --bg-deep: #0a0e17;
  --bg-card: #111827;
  --bg-card-hover: #1a2332;
  --accent-cyan: #06d6a0;
  --accent-blue: #118ab2;
  --accent-warm: #ef8354;
  --text-primary: #e8edf5;
  --text-secondary: #8b95a8;
  --text-muted: #5a6478;
  --border-subtle: rgba(255,255,255,0.06);
  --border-accent: rgba(6,214,160,0.25);
  --glow-cyan: rgba(6,214,160,0.15);
  --glow-blue: rgba(17,138,178,0.12);
  --radius-sm: 6px;
  --radius-md: 12px;
  --radius-lg: 20px;
}

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

html { scroll-behavior: smooth; }

body {
  font-family: 'Noto Sans KR', sans-serif;
  background: var(--bg-deep);
  color: var(--text-primary);
  line-height: 1.7;
  overflow-x: hidden;
}

.theme-toggle {
  width: 36px; height: 36px;
  border-radius: 50%;
  border: 1px solid var(--border-subtle);
  background: var(--bg-card);
  cursor: pointer;
  display: flex; align-items: center; justify-content: center;
  font-size: 16px; line-height: 1;
  transition: all 0.3s ease;
  box-shadow: var(--shadow-sm, none);
}
.theme-toggle:hover {
  border-color: var(--accent-primary);
  transform: scale(1.08);
}

/* ─── LIGHT THEME (default) ─── */
[data-theme="light"] {
  --bg-base: #faf9f7;
  --bg-warm: #fef8f4;
  --bg-card: #ffffff;
  --bg-card-hover: #fffcfa;
  --accent-primary: #f52e3c;
  --accent-secondary: #f59a1b;
  --accent-tertiary: #f5cdbf;
  --accent-deep: #c9222e;
  --gradient-main: linear-gradient(135deg, #f52e3c, #f59a1b);
  --gradient-soft: linear-gradient(135deg, #f59a1b, #f5cdbf);
  --gradient-full: linear-gradient(135deg, #f52e3c, #f59a1b, #f5cdbf);
  --text-primary: #1a1a1a;
  --text-body: #3d3d3d;
  --text-secondary: #6b6b6b;
  --text-muted: #9a9a9a;
  --border-subtle: rgba(0,0,0,0.06);
  --border-accent: rgba(245,46,60,0.15);
  --shadow-sm: 0 1px 3px rgba(0,0,0,0.04), 0 1px 2px rgba(0,0,0,0.03);
  --shadow-md: 0 4px 16px rgba(0,0,0,0.06), 0 1px 4px rgba(0,0,0,0.04);
  --shadow-lg: 0 12px 40px rgba(0,0,0,0.08), 0 4px 12px rgba(0,0,0,0.04);
  --shadow-glow: 0 4px 24px rgba(245,46,60,0.18);
  --nav-bg: rgba(250,249,247,0.82);
  --footer-bg: #1a1a1a;
  --footer-text: #d4d4d4;
  --footer-muted: #888;
  --footer-link: #999;
  --footer-link-hover: #f59a1b;
  --footer-border: rgba(255,255,255,0.08);
  --blob-1: radial-gradient(circle, #f5cdbf, transparent 70%);
  --blob-2: radial-gradient(circle, rgba(245,154,27,0.15), transparent 70%);
  --grid-color: transparent;
  --research-bg: #fef8f4;
}

/* ─── DARK THEME ─── */
[data-theme="dark"] {
  --bg-base: #0a0e17;
  --bg-warm: #0d1220;
  --bg-card: #111827;
  --bg-card-hover: #1a2332;
  --accent-primary: #f55a64;
  --accent-secondary: #f5a83b;
  --accent-tertiary: #f5cdbf;
  --accent-deep: #f52e3c;
  --gradient-main: linear-gradient(135deg, #f52e3c, #f59a1b);
  --gradient-soft: linear-gradient(135deg, #f59a1b, #f5cdbf);
  --gradient-full: linear-gradient(135deg, #f52e3c, #f59a1b, #f5cdbf);
  --text-primary: #e8edf5;
  --text-body: #c0c8d8;
  --text-secondary: #8b95a8;
  --text-muted: #5a6478;
  --border-subtle: rgba(255,255,255,0.06);
  --border-accent: rgba(245,46,60,0.25);
  --shadow-sm: none;
  --shadow-md: 0 4px 16px rgba(0,0,0,0.3);
  --shadow-lg: 0 12px 40px rgba(0,0,0,0.4);
  --shadow-glow: 0 4px 24px rgba(245,46,60,0.3);
  --nav-bg: rgba(10,14,23,0.85);
  --footer-bg: #060911;
  --footer-text: #d4d4d4;
  --footer-muted: #5a6478;
  --footer-link: #6b7890;
  --footer-link-hover: #f5a83b;
  --footer-border: rgba(255,255,255,0.06);
  --blob-1: radial-gradient(circle, rgba(245,46,60,0.08), transparent 70%);
  --blob-2: radial-gradient(circle, rgba(245,154,27,0.06), transparent 70%);
  --grid-color: rgba(245,154,27,0.02);
  --research-bg: rgba(255,255,255,0.01);
}

/* ── UTILITY ── */
.container { max-width: 1200px; margin: 0 auto; padding: 0 24px; }
.en { font-family: 'Space Grotesk', sans-serif; }
.mono { font-family: 'JetBrains Mono', monospace; }
.accent { color: var(--accent-cyan); }
.accent-warm { color: var(--accent-warm); }

/* ── ANIMATED BACKGROUND ── */
.bg-grid {
  position: fixed; inset: 0; z-index: 0; pointer-events: none;
  background-image:
    linear-gradient(rgba(6,214,160,0.03) 1px, transparent 1px),
    linear-gradient(90deg, rgba(6,214,160,0.03) 1px, transparent 1px);
  background-size: 60px 60px;
}

.bg-glow {
  position: fixed; z-index: 0; pointer-events: none;
  width: 600px; height: 600px; border-radius: 50%;
  filter: blur(120px); opacity: 0.4;
}
.bg-glow-1 { top: -200px; right: -100px; background: var(--glow-blue); }
.bg-glow-2 { bottom: -200px; left: -100px; background: var(--glow-cyan); opacity: 0.2; }

/* ── NAV ── */
nav {
  position: fixed; top: 0; left: 0; right: 0; z-index: 100;
  background: rgba(10,14,23,0.85);
  backdrop-filter: blur(20px);
  border-bottom: 1px solid var(--border-subtle);
  transition: all 0.3s ease;
}
nav .container {
  display: flex; align-items: center; justify-content: space-between;
  height: 64px;
}
.nav-logo {
  display: flex; align-items: center; gap: 12px;
  text-decoration: none; color: var(--text-primary);
}
.nav-logo-icon {
  width: 36px; height: 36px;
  background: linear-gradient(135deg, var(--accent-cyan), var(--accent-blue));
  border-radius: 8px;
  display: flex; align-items: center; justify-content: center;
  font-weight: 900; font-size: 14px; color: var(--bg-deep);
  letter-spacing: -0.5px;
}
.nav-logo-text { font-weight: 700; font-size: 15px; letter-spacing: -0.3px; }
.nav-logo-text .sub { font-size: 11px; color: var(--text-secondary); font-weight: 400; display: block; line-height: 1.2; margin-top: 1px; }
.nav-links { display: flex; gap: 6px; list-style: none; }
.nav-links a {
  color: var(--text-secondary); text-decoration: none;
  padding: 8px 16px; border-radius: var(--radius-sm);
  font-size: 14px; font-weight: 500; transition: all 0.2s;
}
.nav-links a:hover { color: var(--text-primary); background: rgba(255,255,255,0.05); }
.nav-links a.active { color: var(--accent-cyan); }
.lang-toggle {
  font-size: 12px; padding: 6px 12px;
  border: 1px solid var(--border-subtle); border-radius: 20px;
  color: var(--text-secondary); background: transparent;
  cursor: pointer; transition: all 0.2s;
}
.lang-toggle:hover { border-color: var(--accent-cyan); color: var(--accent-cyan); }

.mobile-menu-btn { display: none; background: none; border: none; color: var(--text-primary); cursor: pointer; font-size: 24px; }

/* ── HERO ── */
.hero {
  position: relative; z-index: 1;
  min-height: 100vh; display: flex; align-items: center;
  padding-top: 64px;
}
.hero-inner {
  display: grid; grid-template-columns: 1fr 1fr;
  gap: 80px; align-items: center;
  padding: 80px 0;
}
.hero-badge {
  display: inline-flex; align-items: center; gap: 8px;
  padding: 6px 16px 6px 8px;
  background: rgba(6,214,160,0.08);
  border: 1px solid var(--border-accent);
  border-radius: 20px;
  font-size: 12px; color: var(--accent-cyan);
  margin-bottom: 28px;
  animation: fadeSlideUp 0.8s ease-out;
}
.hero-badge-dot {
  width: 8px; height: 8px; border-radius: 50%;
  background: var(--accent-cyan);
  animation: pulse 2s ease-in-out infinite;
}
@keyframes pulse {
  0%, 100% { opacity: 1; transform: scale(1); }
  50% { opacity: 0.5; transform: scale(0.8); }
}
.hero h1 {
  font-size: clamp(36px, 5vw, 56px);
  font-weight: 900; line-height: 1.2;
  letter-spacing: -1.5px;
  margin-bottom: 10px;
  animation: fadeSlideUp 0.8s ease-out 0.1s both;
}
.hero h1 .line2 {
  background: linear-gradient(135deg, var(--accent-cyan), var(--accent-blue));
  -webkit-background-clip: text; -webkit-text-fill-color: transparent;
  background-clip: text;
}
.hero-subtitle-en {
  font-family: 'Space Grotesk', sans-serif;
  font-size: 18px; color: var(--text-secondary);
  font-weight: 500; margin-bottom: 32px;
  animation: fadeSlideUp 0.8s ease-out 0.2s both;
}
.hero-desc {
  font-size: 16px; color: var(--text-secondary);
  line-height: 1.9; max-width: 520px;
  margin-bottom: 40px;
  animation: fadeSlideUp 0.8s ease-out 0.3s both;
}
.hero-actions {
  display: flex; gap: 14px; flex-wrap: wrap;
  animation: fadeSlideUp 0.8s ease-out 0.4s both;
}
.btn {
  display: inline-flex; align-items: center; gap: 8px;
  padding: 14px 28px; border-radius: var(--radius-sm);
  font-size: 14px; font-weight: 600; text-decoration: none;
  transition: all 0.3s ease; cursor: pointer; border: none;
}
.btn-primary {
  background: linear-gradient(135deg, var(--accent-cyan), var(--accent-blue));
  color: var(--bg-deep);
  box-shadow: 0 4px 24px rgba(6,214,160,0.25);
}
.btn-primary:hover { transform: translateY(-2px); box-shadow: 0 8px 32px rgba(6,214,160,0.35); }
.btn-outline {
  background: transparent;
  border: 1px solid var(--border-subtle);
  color: var(--text-primary);
}
.btn-outline:hover { border-color: var(--accent-cyan); color: var(--accent-cyan); }

/* Hero Visual */
.hero-visual {
  position: relative; display: flex; justify-content: center;
  animation: fadeSlideUp 1s ease-out 0.3s both;
}
.hero-orb {
  width: 400px; height: 400px; position: relative;
}
.hero-orb-ring {
  position: absolute; border-radius: 50%;
  border: 1px solid rgba(6,214,160,0.12);
  animation: spinSlow 20s linear infinite;
}
.hero-orb-ring:nth-child(1) { inset: 0; }
.hero-orb-ring:nth-child(2) { inset: 30px; border-color: rgba(17,138,178,0.15); animation-direction: reverse; animation-duration: 15s; }
.hero-orb-ring:nth-child(3) { inset: 60px; border-color: rgba(6,214,160,0.08); animation-duration: 25s; }
.hero-orb-center {
  position: absolute; top: 50%; left: 50%;
  transform: translate(-50%, -50%);
  width: 160px; height: 160px;
  background: radial-gradient(circle, rgba(6,214,160,0.2), rgba(17,138,178,0.1), transparent);
  border-radius: 50%;
  display: flex; align-items: center; justify-content: center;
  flex-direction: column;
}
.hero-orb-label {
  font-family: 'JetBrains Mono', monospace;
  font-size: 11px; color: var(--accent-cyan);
  text-transform: uppercase; letter-spacing: 2px;
  text-align: center; line-height: 1.6;
}
.hero-orb-dot {
  position: absolute; width: 8px; height: 8px;
  background: var(--accent-cyan);
  border-radius: 50;
  box-shadow: 0 0 12px var(--accent-cyan);
}
.hero-orb-dot:nth-child(5) { top: 0; left: 50%; transform: translateX(-50%); }
.hero-orb-dot:nth-child(6) { bottom: 30px; right: 30px; background: var(--accent-blue); box-shadow: 0 0 12px var(--accent-blue); }
.hero-orb-dot:nth-child(7) { bottom: 30px; left: 30px; background: var(--accent-warm); box-shadow: 0 0 12px var(--accent-warm); }

@keyframes spinSlow { to { transform: rotate(360deg); } }
@keyframes fadeSlideUp {
  from { opacity: 0; transform: translateY(24px); }
  to { opacity: 1; transform: translateY(0); }
}

/* ── STATS BAR ── */
.stats-bar {
  position: relative; z-index: 1;
  border-top: 1px solid var(--border-subtle);
  border-bottom: 1px solid var(--border-subtle);
  padding: 48px 0;
}
.stats-grid {
  display: grid; grid-template-columns: repeat(4, 1fr);
  gap: 32px;
}
.stat-item { text-align: center; }
.stat-number {
  font-family: 'Space Grotesk', sans-serif;
  font-size: 36px; font-weight: 700;
  background: linear-gradient(135deg, var(--accent-cyan), var(--accent-blue));
  -webkit-background-clip: text; -webkit-text-fill-color: transparent;
  background-clip: text;
  margin-bottom: 4px;
}
.stat-label { font-size: 13px; color: var(--text-secondary); }

/* ── SECTIONS ── */
section {
  position: relative; z-index: 1;
  padding: 100px 0;
}
.section-label {
  font-family: 'JetBrains Mono', monospace;
  font-size: 11px; color: var(--accent-cyan);
  text-transform: uppercase; letter-spacing: 3px;
  margin-bottom: 12px;
}
.section-title {
  font-size: clamp(28px, 3.5vw, 40px);
  font-weight: 800; letter-spacing: -1px;
  margin-bottom: 16px;
}
.section-subtitle {
  font-size: 16px; color: var(--text-secondary);
  max-width: 600px; margin-bottom: 56px;
}

/* ── ABOUT (Two Orgs) ── */
.about-grid {
  display: grid; grid-template-columns: 1fr 1fr;
  gap: 24px;
}
.org-card {
  background: var(--bg-card);
  border: 1px solid var(--border-subtle);
  border-radius: var(--radius-lg);
  padding: 48px 40px;
  transition: all 0.3s ease;
  position: relative; overflow: hidden;
}
.org-card::before {
  content: '';
  position: absolute; top: 0; left: 0; right: 0;
  height: 3px;
  background: linear-gradient(90deg, var(--accent-cyan), var(--accent-blue));
  opacity: 0; transition: opacity 0.3s ease;
}
.org-card:hover { border-color: var(--border-accent); background: var(--bg-card-hover); }
.org-card:hover::before { opacity: 1; }
.org-card:nth-child(2)::before {
  background: linear-gradient(90deg, var(--accent-warm), #e76f51);
}
.org-icon {
  width: 52px; height: 52px; border-radius: 14px;
  display: flex; align-items: center; justify-content: center;
  font-size: 22px; margin-bottom: 24px;
}
.org-icon.society { background: rgba(6,214,160,0.1); color: var(--accent-cyan); }
.org-icon.institute { background: rgba(239,131,84,0.1); color: var(--accent-warm); }
.org-name { font-size: 22px; font-weight: 800; margin-bottom: 4px; }
.org-name-en {
  font-family: 'Space Grotesk', sans-serif;
  font-size: 13px; color: var(--text-muted);
  margin-bottom: 20px;
}
.org-desc {
  font-size: 15px; color: var(--text-secondary);
  line-height: 1.9; margin-bottom: 24px;
}
.org-features { list-style: none; }
.org-features li {
  padding: 8px 0;
  font-size: 14px; color: var(--text-secondary);
  display: flex; align-items: center; gap: 10px;
}
.org-features li::before {
  content: '→'; color: var(--accent-cyan); font-weight: 600;
  font-family: 'Space Grotesk', sans-serif;
}
.org-card:nth-child(2) .org-features li::before { color: var(--accent-warm); }

/* ── RESEARCH AREAS ── */
.research-grid {
  display: grid; grid-template-columns: repeat(3, 1fr);
  gap: 20px;
}
.research-card {
  background: var(--bg-card);
  border: 1px solid var(--border-subtle);
  border-radius: var(--radius-md);
  padding: 36px 28px;
  transition: all 0.3s ease;
  cursor: default;
}
.research-card:hover {
  border-color: var(--border-accent);
  transform: translateY(-4px);
  box-shadow: 0 12px 40px rgba(0,0,0,0.3);
}
.research-num {
  font-family: 'Space Grotesk', sans-serif;
  font-size: 11px; color: var(--text-muted);
  margin-bottom: 16px; letter-spacing: 1px;
}
.research-title {
  font-size: 17px; font-weight: 700;
  margin-bottom: 10px;
}
.research-desc {
  font-size: 13px; color: var(--text-secondary);
  line-height: 1.8;
}

/* ── NEWS / ANNOUNCEMENTS ── */
.news-grid {
  display: grid; grid-template-columns: 1fr 1fr;
  gap: 24px;
}
.news-main {
  grid-column: 1 / -1;
  background: linear-gradient(135deg, rgba(6,214,160,0.06), rgba(17,138,178,0.04));
  border: 1px solid var(--border-accent);
  border-radius: var(--radius-lg);
  padding: 48px;
  position: relative; overflow: hidden;
}
.news-main::after {
  content: ''; position: absolute; top: -50%; right: -20%;
  width: 400px; height: 400px; border-radius: 50%;
  background: radial-gradient(circle, rgba(6,214,160,0.06), transparent);
  pointer-events: none;
}
.news-tag {
  display: inline-block;
  padding: 4px 12px; border-radius: 4px;
  font-size: 11px; font-weight: 600;
  text-transform: uppercase; letter-spacing: 1px;
  margin-bottom: 16px;
}
.news-tag.announcement { background: rgba(6,214,160,0.15); color: var(--accent-cyan); }
.news-tag.event { background: rgba(239,131,84,0.15); color: var(--accent-warm); }
.news-tag.call { background: rgba(17,138,178,0.15); color: var(--accent-blue); }
.news-title { font-size: 22px; font-weight: 700; margin-bottom: 12px; }
.news-excerpt { font-size: 15px; color: var(--text-secondary); line-height: 1.8; }
.news-date {
  font-family: 'JetBrains Mono', monospace;
  font-size: 12px; color: var(--text-muted);
  margin-top: 16px;
}

.news-item {
  background: var(--bg-card);
  border: 1px solid var(--border-subtle);
  border-radius: var(--radius-md);
  padding: 32px;
  transition: all 0.3s ease;
}
.news-item:hover { border-color: var(--border-accent); }
.news-item .news-title { font-size: 17px; }
.news-item .news-excerpt { font-size: 14px; }

/* ── MEMBERSHIP CTA ── */
.cta-section {
  text-align: center;
  padding: 100px 0;
}
.cta-box {
  background: linear-gradient(135deg, rgba(6,214,160,0.08), rgba(17,138,178,0.05));
  border: 1px solid var(--border-accent);
  border-radius: var(--radius-lg);
  padding: 72px 48px;
  max-width: 800px; margin: 0 auto;
  position: relative; overflow: hidden;
}
.cta-box::before {
  content: ''; position: absolute; inset: 0;
  background:
    radial-gradient(ellipse at 20% 50%, rgba(6,214,160,0.05), transparent 50%),
    radial-gradient(ellipse at 80% 50%, rgba(17,138,178,0.05), transparent 50%);
  pointer-events: none;
}
.cta-title {
  font-size: clamp(26px, 3vw, 36px);
  font-weight: 800; letter-spacing: -0.5px;
  margin-bottom: 16px; position: relative;
}
.cta-desc {
  font-size: 16px; color: var(--text-secondary);
  margin-bottom: 36px; position: relative;
}

/* ── FOOTER ── */
footer {
  position: relative; z-index: 1;
  border-top: 1px solid var(--border-subtle);
  padding: 64px 0 40px;
}
.footer-grid {
  display: grid; grid-template-columns: 2fr 1fr 1fr 1fr;
  gap: 48px;
  margin-bottom: 48px;
}
.footer-brand { }
.footer-logo {
  display: flex; align-items: center; gap: 10px;
  margin-bottom: 16px;
}
.footer-logo-icon {
  width: 32px; height: 32px;
  background: linear-gradient(135deg, var(--accent-cyan), var(--accent-blue));
  border-radius: 7px;
  display: flex; align-items: center; justify-content: center;
  font-weight: 900; font-size: 12px; color: var(--bg-deep);
}
.footer-logo-name { font-weight: 700; font-size: 15px; }
.footer-about { font-size: 13px; color: var(--text-secondary); line-height: 1.8; max-width: 320px; }
.footer-col-title {
  font-size: 12px; font-weight: 700;
  text-transform: uppercase; letter-spacing: 1.5px;
  color: var(--text-muted); margin-bottom: 20px;
}
.footer-links { list-style: none; }
.footer-links li { margin-bottom: 10px; }
.footer-links a {
  font-size: 14px; color: var(--text-secondary);
  text-decoration: none; transition: color 0.2s;
}
.footer-links a:hover { color: var(--accent-cyan); }
.footer-bottom {
  border-top: 1px solid var(--border-subtle);
  padding-top: 24px;
  display: flex; justify-content: space-between; align-items: center;
}
.footer-copy { font-size: 12px; color: var(--text-muted); }
.footer-contact-info { font-size: 12px; color: var(--text-muted); }
.footer-contact-info a { color: var(--accent-cyan); text-decoration: none; }

/* ── RESPONSIVE ── */
@media (max-width: 968px) {
  .hero-inner { grid-template-columns: 1fr; gap: 48px; text-align: center; }
  .hero-desc { margin-left: auto; margin-right: auto; }
  .hero-actions { justify-content: center; }
  .hero-visual { order: -1; }
  .hero-orb { width: 280px; height: 280px; }
  .about-grid { grid-template-columns: 1fr; }
  .research-grid { grid-template-columns: 1fr 1fr; }
  .stats-grid { grid-template-columns: repeat(2, 1fr); gap: 24px; }
  .footer-grid { grid-template-columns: 1fr 1fr; }
  .news-grid { grid-template-columns: 1fr; }
}
@media (max-width: 640px) {
  .nav-links { display: none; }
  .mobile-menu-btn { display: block; }
  .hero-inner { padding: 40px 0; }
  .research-grid { grid-template-columns: 1fr; }
  .stats-grid { grid-template-columns: 1fr 1fr; }
  .footer-grid { grid-template-columns: 1fr; gap: 32px; }
  .footer-bottom { flex-direction: column; gap: 8px; text-align: center; }
  .cta-box { padding: 48px 24px; }
  .org-card { padding: 32px 24px; }
  .news-main { padding: 32px 24px; }
}

/* Additional styles can be added below */
body       { background: var(--bg-base); color: var(--text-primary); }
nav        { background: var(--nav-bg); }
footer     { background: var(--footer-bg); color: var(--footer-text); }
.bg-blob-1 { background: var(--blob-1); }
.bg-blob-2 { background: var(--blob-2); }