/* 
  E-Park AI CSS Design System
  SVAIFF Matching Theme: Pure Black (#000000) & Rich Gold (#D4AF37)
*/

@import url('https://fonts.googleapis.com/css2?family=Inter:wght@300;400;500;600;700&family=Noto+Serif+KR:wght@300;400;600;700&display=swap');

:root {
  /* Color Tokens */
  --bg-color: #000000;
  --bg-card: rgba(18, 18, 18, 0.6);
  --bg-card-hover: rgba(26, 26, 26, 0.85);
  --accent-gold: #D4AF37;
  --accent-gold-rgb: 212, 175, 55;
  --accent-amber: #FFBF00;
  --accent-amber-rgb: 255, 191, 0;
  --text-primary: #FFFFFF;
  --text-secondary: #CCCCCC;
  --text-muted: #888888;
  --border-color: rgba(212, 175, 55, 0.15);
  --border-hover: rgba(212, 175, 55, 0.35);
  
  /* Typography */
  --font-serif: 'Noto Serif KR', serif;
  --font-sans: 'Inter', -apple-system, BlinkMacSystemFont, "Segoe UI", Roboto, sans-serif;
  
  /* Spacing */
  --container-max: 1200px;
  --nav-height: 80px;
}

/* Base Styles */
* {
  margin: 0;
  padding: 0;
  box-sizing: border-box;
}

html {
  scroll-behavior: smooth;
  background-color: var(--bg-color);
  color: var(--text-primary);
  font-family: var(--font-sans);
  overflow-x: hidden;
}

body {
  min-height: 100vh;
  position: relative;
  line-height: 1.6;
  -webkit-font-smoothing: antialiased;
}

/* Background Glowing Effects */
body::before {
  content: "";
  position: absolute;
  top: -10%;
  left: 10%;
  width: 50vw;
  height: 50vw;
  background: radial-gradient(circle, rgba(212, 175, 55, 0.08) 0%, transparent 70%);
  z-index: -1;
  pointer-events: none;
}

body::after {
  content: "";
  position: absolute;
  bottom: 10%;
  right: -5%;
  width: 45vw;
  height: 45vw;
  background: radial-gradient(circle, rgba(255, 191, 0, 0.05) 0%, transparent 75%);
  z-index: -1;
  pointer-events: none;
}

/* Custom Scrollbar */
::-webkit-scrollbar {
  width: 8px;
}
::-webkit-scrollbar-track {
  background: var(--bg-color);
}
::-webkit-scrollbar-thumb {
  background: #333333;
  border-radius: 4px;
}
::-webkit-scrollbar-thumb:hover {
  background: var(--accent-gold);
}

/* Navigation Bar */
.navbar {
  position: fixed;
  top: 0;
  left: 0;
  width: 100%;
  height: var(--nav-height);
  background: rgba(0, 0, 0, 0.75);
  backdrop-filter: blur(20px);
  -webkit-backdrop-filter: blur(20px);
  border-bottom: 1px solid rgba(255, 255, 255, 0.05);
  z-index: 1000;
  transition: all 0.3s ease;
}

.navbar.scrolled {
  background: rgba(0, 0, 0, 0.9);
  height: 70px;
}

.nav-container {
  max-width: var(--container-max);
  margin: 0 auto;
  height: 100%;
  padding: 0 24px;
  display: flex;
  justify-content: space-between;
  align-items: center;
}

.nav-brand {
  display: flex;
  align-items: center;
  gap: 12px;
  text-decoration: none;
  color: var(--text-primary);
  font-weight: 600;
  font-size: 20px;
  letter-spacing: -0.02em;
}

.nav-brand img {
  height: 28px;
  width: auto;
  object-fit: contain;
}

.nav-menu {
  display: flex;
  align-items: center;
  gap: 32px;
  list-style: none;
}

.nav-link {
  text-decoration: none;
  color: var(--text-secondary);
  font-size: 15px;
  font-weight: 500;
  transition: color 0.3s ease;
  position: relative;
  padding: 4px 0;
}

.nav-link:hover {
  color: var(--accent-gold);
}

.nav-link::after {
  content: "";
  position: absolute;
  bottom: 0;
  left: 0;
  width: 0;
  height: 2px;
  background-color: var(--accent-gold);
  transition: width 0.3s ease;
}

.nav-link:hover::after {
  width: 100%;
}

.nav-actions {
  display: flex;
  align-items: center;
  gap: 16px;
}

/* Language Switcher */
.lang-switcher {
  display: flex;
  gap: 4px;
  border: 1px solid rgba(255, 255, 255, 0.1);
  padding: 2px;
  border-radius: 6px;
}

.lang-btn {
  background: none;
  border: none;
  color: var(--text-muted);
  padding: 4px 8px;
  font-size: 12px;
  font-weight: 600;
  cursor: pointer;
  border-radius: 4px;
  transition: all 0.3s ease;
}

.lang-btn.active {
  background: var(--accent-gold);
  color: var(--bg-color);
}

/* Hamburger Menu (Mobile) */
.hamburger {
  display: none;
  flex-direction: column;
  gap: 6px;
  cursor: pointer;
  background: none;
  border: none;
  padding: 4px;
}

.hamburger span {
  display: block;
  width: 25px;
  height: 2px;
  background-color: var(--text-primary);
  transition: all 0.3s ease;
}

/* Layout Utilities */
.container {
  max-width: var(--container-max);
  margin: 0 auto;
  padding: 0 24px;
}

section {
  padding: 100px 0;
  position: relative;
}

/* Hero Section */
.hero-section {
  min-height: 100vh;
  display: flex;
  align-items: center;
  padding-top: calc(var(--nav-height) + 40px);
  text-align: center;
}

.hero-content {
  max-width: 900px;
  margin: 0 auto;
}

.hero-subtitle {
  color: var(--accent-gold);
  font-size: 14px;
  font-weight: 700;
  text-transform: uppercase;
  letter-spacing: 0.15em;
  margin-bottom: 24px;
}

.hero-title {
  font-family: var(--font-serif);
  font-size: clamp(36px, 5.5vw, 68px);
  font-weight: 600;
  line-height: 1.15;
  letter-spacing: -0.02em;
  margin-bottom: 28px;
  color: var(--text-primary);
}

.hero-description {
  color: var(--text-secondary);
  font-size: clamp(16px, 2vw, 19px);
  line-height: 1.65;
  max-width: 72ch;
  margin: 0 auto 40px;
}

.hero-cta {
  display: flex;
  gap: 16px;
  justify-content: center;
  flex-wrap: wrap;
}

/* Buttons */
.btn {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  padding: 14px 28px;
  font-size: 15px;
  font-weight: 600;
  text-decoration: none;
  border-radius: 8px;
  transition: all 0.3s ease;
  cursor: pointer;
}

.btn-gold {
  background: var(--accent-gold);
  color: var(--bg-color);
  border: 1px solid var(--accent-gold);
}

.btn-gold:hover {
  background: var(--accent-amber);
  border-color: var(--accent-amber);
  box-shadow: 0 0 20px rgba(255, 191, 0, 0.4);
}

.btn-outline {
  background: transparent;
  color: var(--text-primary);
  border: 1px solid rgba(255, 255, 255, 0.25);
}

.btn-outline:hover {
  border-color: var(--accent-gold);
  color: var(--accent-gold);
  background: rgba(212, 175, 55, 0.05);
}

/* Common Section Typography */
.section-kicker {
  color: var(--accent-gold);
  font-size: 13px;
  font-weight: 700;
  text-transform: uppercase;
  letter-spacing: 0.1em;
  margin-bottom: 16px;
  display: block;
}

.section-title {
  font-family: var(--font-serif);
  font-size: clamp(28px, 3.5vw, 42px);
  font-weight: 600;
  letter-spacing: -0.01em;
  margin-bottom: 24px;
}

.section-desc {
  color: var(--text-secondary);
  font-size: 16px;
  line-height: 1.7;
  max-width: 65ch;
  margin-bottom: 48px;
}

/* Grid & Cards (Glassmorphism) */
.glass-grid {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(280px, 1fr));
  gap: 32px;
}

.glass-card {
  background: var(--bg-card);
  border: 1px solid var(--border-color);
  border-radius: 12px;
  padding: 36px;
  backdrop-filter: blur(12px);
  -webkit-backdrop-filter: blur(12px);
  transition: all 0.3s cubic-bezier(0.25, 0.8, 0.25, 1);
  position: relative;
  overflow: hidden;
}

.glass-card::before {
  content: "";
  position: absolute;
  top: 0;
  left: 0;
  width: 100%;
  height: 100%;
  background: linear-gradient(135deg, rgba(212, 175, 55, 0.03) 0%, transparent 100%);
  opacity: 0;
  transition: opacity 0.3s ease;
  pointer-events: none;
}

.glass-card:hover {
  background: var(--bg-card-hover);
  border-color: var(--border-hover);
  transform: translateY(-5px);
  box-shadow: 0 10px 30px rgba(212, 175, 55, 0.05);
}

.glass-card:hover::before {
  opacity: 1;
}

.card-num {
  font-family: var(--font-serif);
  font-size: 40px;
  font-weight: 700;
  color: rgba(212, 175, 55, 0.2);
  line-height: 1;
  margin-bottom: 20px;
  transition: color 0.3s ease;
}

.glass-card:hover .card-num {
  color: var(--accent-gold);
}

.card-title {
  font-family: var(--font-serif);
  font-size: 22px;
  font-weight: 600;
  margin-bottom: 12px;
}

.card-copy {
  color: var(--text-secondary);
  font-size: 14.5px;
  line-height: 1.6;
}

/* SVAIFF Korea Timeline Section */
.svaiff-dates {
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: 40px;
  margin-top: 48px;
}

.date-card {
  border-top: 2px solid var(--border-color);
  padding: 30px 0;
  transition: border-color 0.3s ease;
}

.date-card:hover {
  border-color: var(--accent-gold);
}

.date-number {
  font-family: var(--font-serif);
  font-size: clamp(32px, 4vw, 48px);
  font-weight: 700;
  color: var(--accent-gold);
  line-height: 1;
  margin-bottom: 20px;
}

.date-title {
  font-size: 20px;
  font-weight: 600;
  margin-bottom: 8px;
}

.date-desc {
  color: var(--text-secondary);
  font-size: 14.5px;
}

/* Partnerships Table / List */
.partner-list {
  display: flex;
  flex-direction: column;
  gap: 20px;
}

.partner-row {
  display: grid;
  grid-template-columns: 240px 180px 1fr;
  gap: 32px;
  align-items: center;
  padding: 24px 0;
  border-top: 1px solid rgba(255, 255, 255, 0.1);
  transition: all 0.3s ease;
}

.partner-row:hover {
  border-top-color: var(--accent-gold);
  padding-left: 8px;
}

.partner-name {
  font-family: var(--font-serif);
  font-size: 22px;
  font-weight: 600;
  color: var(--text-primary);
}

.partner-role {
  color: var(--accent-gold);
  font-size: 13px;
  font-weight: 700;
  text-transform: uppercase;
  letter-spacing: 0.05em;
}

.partner-desc {
  color: var(--text-secondary);
  font-size: 15px;
  line-height: 1.6;
}

/* Columns Split */
.split-cols {
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: 64px;
  align-items: center;
}

.split-text {
  padding-right: 20px;
}

/* Forms */
.inquiry-container {
  max-width: 680px;
  margin: 0 auto;
}

.form-group {
  margin-bottom: 24px;
}

.form-row {
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: 20px;
}

.form-label {
  display: block;
  font-size: 14px;
  font-weight: 500;
  color: var(--text-secondary);
  margin-bottom: 8px;
}

.form-control {
  width: 100%;
  background: rgba(255, 255, 255, 0.05);
  border: 1px solid rgba(255, 255, 255, 0.1);
  border-radius: 6px;
  padding: 12px 16px;
  color: var(--text-primary);
  font-family: var(--font-sans);
  font-size: 15px;
  transition: all 0.3s ease;
}

.form-control:focus {
  outline: none;
  border-color: var(--accent-gold);
  background: rgba(212, 175, 55, 0.02);
  box-shadow: 0 0 10px rgba(212, 175, 55, 0.1);
}

textarea.form-control {
  resize: vertical;
  min-height: 120px;
}

.checkbox-group {
  display: flex;
  align-items: flex-start;
  gap: 10px;
}

.checkbox-group input[type="checkbox"] {
  margin-top: 4px;
  accent-color: var(--accent-gold);
}

.checkbox-label {
  font-size: 13.5px;
  color: var(--text-secondary);
}

.dynamic-fields {
  display: none;
  animation: fadeIn 0.4s ease forwards;
}

@keyframes fadeIn {
  from { opacity: 0; transform: translateY(10px); }
  to { opacity: 1; transform: translateY(0); }
}

/* Footer */
footer {
  background: #090909;
  border-top: 1px solid rgba(255, 255, 255, 0.05);
  padding: 60px 0;
  font-size: 13.5px;
  color: var(--text-muted);
}

.footer-container {
  max-width: var(--container-max);
  margin: 0 auto;
  padding: 0 24px;
  display: flex;
  justify-content: space-between;
  align-items: center;
  flex-wrap: wrap;
  gap: 24px;
}

.footer-left {
  display: flex;
  align-items: center;
  gap: 10px;
}

.footer-logo {
  height: 24px;
  width: auto;
}

.footer-right {
  display: flex;
  gap: 24px;
}

.footer-link {
  color: var(--text-muted);
  text-decoration: none;
  transition: color 0.3s ease;
}

.footer-link:hover {
  color: var(--accent-gold);
}

/* Responsive Styles */
@media (max-width: 992px) {
  .split-cols {
    grid-template-columns: 1fr;
    gap: 40px;
  }
  .split-text {
    padding-right: 0;
  }
}

@media (max-width: 768px) {
  .hamburger {
    display: flex;
  }
  
  .nav-menu {
    position: fixed;
    top: var(--nav-height);
    left: -100%;
    width: 100%;
    height: calc(100vh - var(--nav-height));
    background: rgba(0, 0, 0, 0.95);
    backdrop-filter: blur(24px);
    flex-direction: column;
    padding: 60px 24px;
    gap: 40px;
    transition: left 0.4s cubic-bezier(0.25, 0.8, 0.25, 1);
  }
  
  .nav-menu.active {
    left: 0;
  }
  
  .nav-link {
    font-size: 18px;
  }
  
  .svaiff-dates {
    grid-template-columns: 1fr;
    gap: 24px;
  }
  
  .partner-row {
    grid-template-columns: 1fr;
    gap: 8px;
    padding: 20px 0;
  }
  
  .form-row {
    grid-template-columns: 1fr;
    gap: 0;
  }
  
  .footer-container {
    flex-direction: column;
    text-align: center;
    align-items: center;
  }
}

/* Theme Toggle Button */
.theme-toggle {
  background: none;
  border: 1px solid rgba(255, 255, 255, 0.15);
  cursor: pointer;
  padding: 6px;
  border-radius: 6px;
  display: inline-flex;
  align-items: center;
  justify-content: center;
  color: var(--text-primary);
  transition: all 0.3s ease;
  width: 32px;
  height: 32px;
}

.theme-toggle:hover {
  border-color: var(--accent-gold);
  color: var(--accent-gold);
  background: rgba(212, 175, 55, 0.05);
}

html.light-theme, body.light-theme, :root.light-theme {
  --bg-color: #F7F7FA;
  --bg-card: rgba(255, 255, 255, 0.85);
  --bg-card-hover: rgba(255, 255, 255, 0.98);
  --text-primary: #121212;
  --text-secondary: #444444;
  --text-muted: #777777;
  --border-color: rgba(212, 175, 55, 0.25);
  --border-hover: rgba(212, 175, 55, 0.55);
}

html.light-theme section,
body.light-theme section,
html.light-theme .hero-section,
body.light-theme .hero-section {
  background-color: var(--bg-color) !important;
  background: var(--bg-color) !important;
}

body.light-theme::before, body.light-theme::after {
  opacity: 0.35;
}

body.light-theme .navbar {
  background: rgba(255, 255, 255, 0.85);
  border-bottom: 1px solid rgba(0, 0, 0, 0.05);
}

body.light-theme .navbar.scrolled {
  background: rgba(255, 255, 255, 0.95);
}

body.light-theme .nav-link {
  color: #333333;
}

body.light-theme .nav-link:hover {
  color: var(--accent-gold);
}

body.light-theme .nav-brand {
  color: #121212;
}

body.light-theme .hamburger span {
  background-color: #121212;
}

body.light-theme footer {
  background: #EAEAEF;
  border-top: 1px solid rgba(0, 0, 0, 0.05);
  color: #666666;
}

body.light-theme footer .footer-link {
  color: #666666;
}

body.light-theme footer .footer-link:hover {
  color: var(--accent-gold);
}

body.light-theme .form-control {
  background: rgba(0, 0, 0, 0.02);
  border: 1px solid rgba(0, 0, 0, 0.1);
  color: #121212;
}

body.light-theme .form-control:focus {
  border-color: var(--accent-gold);
  background: rgba(212, 175, 55, 0.01);
}

body.light-theme select.form-control {
  background-color: #ffffff !important;
  color: #121212 !important;
}

body.light-theme .dynamic-fields select {
  background-color: #ffffff !important;
}

body.light-theme .partner-row {
  border-top-color: rgba(0, 0, 0, 0.1);
}

body.light-theme .partner-name {
  color: #121212;
}

body.light-theme .date-card {
  border-top-color: rgba(0, 0, 0, 0.1);
}

body.light-theme .date-title {
  color: #121212;
}

body.light-theme .corp-table th, body.light-theme .corp-table td {
  border-bottom-color: rgba(0, 0, 0, 0.08);
}

body.light-theme .corp-table td {
  color: #333333;
}

body.light-theme .leader-info p {
  color: #333333;
}

body.light-theme .faq-item {
  border-bottom-color: rgba(0, 0, 0, 0.08);
}

body.light-theme .faq-a {
  color: #333333;
}

body.light-theme .download-card {
  color: #121212;
}

body.light-theme .theme-toggle {
  border-color: rgba(0, 0, 0, 0.15);
  color: #121212;
}

body.light-theme .lang-switcher {
  border-color: rgba(0, 0, 0, 0.1);
}

body.light-theme .lang-btn {
  color: #777777;
}

body.light-theme .lang-btn.active {
  color: var(--bg-color);
}