/* ============================================================
   Skyline Seoul Travel Guide – style.css
   Independent informational travel guide.
   ============================================================ */

/* ---------- CSS Variables ---------- */
:root {
  --primary: #1a365d;
  --primary-light: #2c5282;
  --primary-dark: #0f2440;
  --accent: #e8913a;
  --accent-light: #f6ad55;
  --bg: #f7fafc;
  --bg-alt: #edf2f7;
  --text: #1a202c;
  --text-muted: #4a5568;
  --text-light: #718096;
  --white: #ffffff;
  --border: #e2e8f0;
  --shadow: 0 4px 6px -1px rgba(0,0,0,0.1), 0 2px 4px -1px rgba(0,0,0,0.06);
  --shadow-lg: 0 10px 15px -3px rgba(0,0,0,0.1), 0 4px 6px -2px rgba(0,0,0,0.05);
  --shadow-xl: 0 20px 25px -5px rgba(0,0,0,0.1), 0 10px 10px -5px rgba(0,0,0,0.04);
  --radius: 12px;
  --radius-sm: 8px;
  --transition: 0.3s ease;
  --font-sans: 'Pretendard', -apple-system, BlinkMacSystemFont, 'Segoe UI', Roboto, sans-serif;
  --max-width: 1200px;
}

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

html {
  scroll-behavior: smooth;
  font-size: 16px;
}

body {
  font-family: var(--font-sans);
  color: var(--text);
  background: var(--bg);
  line-height: 1.7;
  -webkit-font-smoothing: antialiased;
}

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

a {
  color: var(--primary-light);
  text-decoration: none;
  transition: color var(--transition);
}

a:hover {
  color: var(--accent);
}

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

/* ---------- Navigation ---------- */
.main-nav {
  position: fixed;
  top: 0;
  left: 0;
  right: 0;
  z-index: 1000;
  background: rgba(255,255,255,0.95);
  backdrop-filter: blur(10px);
  -webkit-backdrop-filter: blur(10px);
  border-bottom: 1px solid transparent;
  transition: all var(--transition);
}

.main-nav.scrolled {
  background: rgba(255,255,255,0.98);
  border-bottom-color: var(--border);
  box-shadow: var(--shadow);
}

.nav-inner {
  display: flex;
  align-items: center;
  justify-content: space-between;
  height: 72px;
  max-width: var(--max-width);
  margin: 0 auto;
  padding: 0 24px;
}

.nav-brand {
  display: flex;
  align-items: center;
  gap: 10px;
  font-weight: 700;
  font-size: 1.1rem;
  color: var(--primary);
  text-decoration: none;
}

.nav-brand i {
  width: 24px;
  height: 24px;
  color: var(--accent);
}

.nav-links {
  display: flex;
  align-items: center;
  gap: 28px;
  list-style: none;
}

.nav-links a {
  font-size: 0.9rem;
  font-weight: 500;
  color: var(--text-muted);
  transition: color var(--transition);
}

.nav-links a:hover {
  color: var(--primary);
}

#langBtn {
  background: var(--primary);
  color: var(--white);
  border: none;
  padding: 6px 16px;
  border-radius: 20px;
  font-size: 0.85rem;
  font-weight: 600;
  cursor: pointer;
  transition: background var(--transition);
}

#langBtn:hover {
  background: var(--primary-light);
}

/* Hamburger */
.nav-toggle {
  display: none;
  flex-direction: column;
  gap: 5px;
  background: none;
  border: none;
  cursor: pointer;
  padding: 4px;
}

.nav-toggle span {
  display: block;
  width: 24px;
  height: 2px;
  background: var(--text);
  transition: all var(--transition);
}

.nav-toggle.active span:nth-child(1) {
  transform: rotate(45deg) translate(5px, 5px);
}

.nav-toggle.active span:nth-child(2) {
  opacity: 0;
}

.nav-toggle.active span:nth-child(3) {
  transform: rotate(-45deg) translate(5px, -5px);
}

/* ---------- Hero ---------- */
.hero {
  position: relative;
  height: 85vh;
  min-height: 500px;
  display: flex;
  align-items: center;
  justify-content: center;
  overflow: hidden;
  margin-top: 72px;
}

.hero-bg {
  position: absolute;
  inset: 0;
  background-size: cover;
  background-position: center;
  background-repeat: no-repeat;
}

.hero-overlay {
  position: absolute;
  inset: 0;
  background: linear-gradient(180deg, rgba(15,36,64,0.4) 0%, rgba(15,36,64,0.7) 100%);
}

.hero-content {
  position: relative;
  z-index: 2;
  text-align: center;
  color: var(--white);
  max-width: 800px;
  padding: 0 24px;
}

.hero-location {
  display: inline-flex;
  align-items: center;
  gap: 6px;
  background: rgba(255,255,255,0.15);
  backdrop-filter: blur(8px);
  padding: 8px 20px;
  border-radius: 24px;
  font-size: 0.9rem;
  margin-bottom: 24px;
}

.hero-location i {
  width: 16px;
  height: 16px;
}

.hero h1 {
  font-size: 3rem;
  font-weight: 800;
  line-height: 1.15;
  margin-bottom: 16px;
  letter-spacing: -0.02em;
}

.hero-subtitle {
  font-size: 1.15rem;
  opacity: 0.9;
  margin-bottom: 28px;
  line-height: 1.6;
}

.hero-badge {
  display: inline-flex;
  align-items: center;
  gap: 8px;
  background: var(--accent);
  color: var(--white);
  padding: 10px 24px;
  border-radius: 24px;
  font-weight: 600;
  font-size: 0.95rem;
}

.hero-badge i {
  width: 18px;
  height: 18px;
}

/* ---------- Section common ---------- */
.section {
  padding: 80px 0;
}

.section-alt {
  background: var(--bg-alt);
}

.section-header {
  text-align: center;
  margin-bottom: 48px;
}

.section-header h2 {
  font-size: 2rem;
  font-weight: 700;
  color: var(--primary);
  margin-bottom: 12px;
}

.section-header p {
  font-size: 1.05rem;
  color: var(--text-muted);
  max-width: 600px;
  margin: 0 auto;
}

/* ---------- Introduction ---------- */
.intro-text {
  font-size: 1.1rem;
  line-height: 1.8;
  color: var(--text);
  max-width: 800px;
  margin: 0 auto 40px;
  text-align: center;
}

.stats-grid {
  display: grid;
  grid-template-columns: repeat(4, 1fr);
  gap: 24px;
}

.stat-card {
  background: var(--white);
  border-radius: var(--radius);
  padding: 28px 20px;
  text-align: center;
  box-shadow: var(--shadow);
  transition: transform var(--transition), box-shadow var(--transition);
}

.stat-card:hover {
  transform: translateY(-4px);
  box-shadow: var(--shadow-lg);
}

.stat-card .stat-icon {
  display: flex;
  align-items: center;
  justify-content: center;
  width: 48px;
  height: 48px;
  background: rgba(26,54,93,0.08);
  border-radius: 12px;
  margin: 0 auto 16px;
  color: var(--primary);
}

.stat-card .stat-icon i {
  width: 24px;
  height: 24px;
}

.stat-value {
  font-size: 1.8rem;
  font-weight: 800;
  color: var(--primary);
  margin-bottom: 4px;
}

.stat-label {
  font-size: 0.85rem;
  color: var(--text-muted);
  font-weight: 500;
}

/* ---------- Articles ---------- */
.articles-grid {
  display: grid;
  grid-template-columns: repeat(2, 1fr);
  gap: 28px;
}

.article-card {
  background: var(--white);
  border-radius: var(--radius);
  overflow: hidden;
  box-shadow: var(--shadow);
  transition: transform var(--transition), box-shadow var(--transition);
}

.article-card:hover {
  transform: translateY(-4px);
  box-shadow: var(--shadow-lg);
}

.article-img-wrap {
  position: relative;
  height: 200px;
  overflow: hidden;
}

.article-img-wrap img {
  width: 100%;
  height: 100%;
  object-fit: cover;
  transition: transform 0.5s ease;
}

.article-card:hover .article-img-wrap img {
  transform: scale(1.08);
}

.article-content {
  padding: 24px;
}

.article-content h3 {
  font-size: 1.15rem;
  font-weight: 700;
  color: var(--primary);
  margin-bottom: 12px;
  line-height: 1.4;
}

.article-excerpt {
  font-size: 0.95rem;
  color: var(--text-muted);
  line-height: 1.6;
  margin-bottom: 16px;
}

.article-body {
  max-height: 0;
  overflow: hidden;
  transition: max-height 0.5s ease;
}

.article-body-inner {
  padding-top: 16px;
  border-top: 1px solid var(--border);
  font-size: 0.95rem;
  color: var(--text);
  line-height: 1.8;
}

.article-toggle {
  display: inline-flex;
  align-items: center;
  gap: 6px;
  background: none;
  border: none;
  color: var(--accent);
  font-weight: 600;
  font-size: 0.9rem;
  cursor: pointer;
  padding: 0;
  transition: color var(--transition);
}

.article-toggle:hover {
  color: var(--primary);
}

/* ---------- Tips ---------- */
.tips-grid {
  display: grid;
  grid-template-columns: repeat(3, 1fr);
  gap: 24px;
}

.tip-card {
  background: var(--white);
  border-radius: var(--radius);
  padding: 28px;
  box-shadow: var(--shadow);
  transition: transform var(--transition);
}

.tip-card:hover {
  transform: translateY(-4px);
}

.tip-icon {
  display: flex;
  align-items: center;
  justify-content: center;
  width: 48px;
  height: 48px;
  background: rgba(232,145,58,0.1);
  border-radius: 12px;
  margin-bottom: 16px;
  color: var(--accent);
}

.tip-icon i {
  width: 24px;
  height: 24px;
}

.tip-card h3 {
  font-size: 1.05rem;
  font-weight: 700;
  color: var(--primary);
  margin-bottom: 8px;
}

.tip-card p {
  font-size: 0.9rem;
  color: var(--text-muted);
  line-height: 1.6;
}

/* ---------- Seasons ---------- */
.seasons-grid {
  display: grid;
  grid-template-columns: repeat(4, 1fr);
  gap: 24px;
}

.season-card {
  background: var(--white);
  border-radius: var(--radius);
  padding: 28px;
  text-align: center;
  box-shadow: var(--shadow);
  border-top: 4px solid var(--primary);
  transition: transform var(--transition);
}

.season-card:hover {
  transform: translateY(-4px);
}

.season-card:nth-child(1) { border-top-color: #f687b3; }
.season-card:nth-child(2) { border-top-color: #48bb78; }
.season-card:nth-child(3) { border-top-color: #ed8936; }
.season-card:nth-child(4) { border-top-color: #63b3ed; }

.season-icon {
  display: flex;
  align-items: center;
  justify-content: center;
  width: 56px;
  height: 56px;
  border-radius: 50%;
  margin: 0 auto 16px;
}

.season-card:nth-child(1) .season-icon { background: rgba(246,135,179,0.1); color: #f687b3; }
.season-card:nth-child(2) .season-icon { background: rgba(72,187,120,0.1); color: #48bb78; }
.season-card:nth-child(3) .season-icon { background: rgba(237,137,54,0.1); color: #ed8936; }
.season-card:nth-child(4) .season-icon { background: rgba(99,179,237,0.1); color: #63b3ed; }

.season-icon i {
  width: 28px;
  height: 28px;
}

.season-card h3 {
  font-size: 1.15rem;
  font-weight: 700;
  color: var(--primary);
  margin-bottom: 4px;
}

.season-months {
  font-size: 0.85rem;
  color: var(--text-light);
  margin-bottom: 12px;
}

.season-card p:last-child {
  font-size: 0.9rem;
  color: var(--text-muted);
  line-height: 1.6;
  text-align: left;
}

/* ---------- Lead Form ---------- */
.form-section {
  background: linear-gradient(135deg, var(--primary) 0%, var(--primary-dark) 100%);
  color: var(--white);
}

.form-section .section-header h2 {
  color: var(--white);
}

.form-section .section-header p {
  color: rgba(255,255,255,0.8);
}

.lead-form {
  max-width: 560px;
  margin: 0 auto;
  background: var(--white);
  border-radius: var(--radius);
  padding: 36px;
  box-shadow: var(--shadow-xl);
}

.form-group {
  margin-bottom: 20px;
}

.form-group label {
  display: block;
  font-size: 0.9rem;
  font-weight: 600;
  color: var(--text);
  margin-bottom: 6px;
}

.form-group input,
.form-group select {
  width: 100%;
  padding: 12px 16px;
  border: 1px solid var(--border);
  border-radius: var(--radius-sm);
  font-size: 0.95rem;
  font-family: var(--font-sans);
  color: var(--text);
  transition: border-color var(--transition);
  background: var(--white);
}

.form-group input:focus,
.form-group select:focus {
  outline: none;
  border-color: var(--primary-light);
  box-shadow: 0 0 0 3px rgba(44,82,130,0.1);
}

.form-group.consent {
  display: flex;
  gap: 12px;
  align-items: flex-start;
}

.form-group.consent input[type="checkbox"] {
  width: 18px;
  height: 18px;
  margin-top: 3px;
  flex-shrink: 0;
}

.form-group.consent label {
  font-size: 0.85rem;
  font-weight: 400;
  color: var(--text-muted);
  line-height: 1.5;
}

.field-error {
  font-size: 0.8rem;
  color: #e53e3e;
  margin-top: 4px;
  min-height: 1.2em;
}

.form-submit {
  width: 100%;
  padding: 14px;
  background: var(--accent);
  color: var(--white);
  border: none;
  border-radius: var(--radius-sm);
  font-size: 1rem;
  font-weight: 700;
  font-family: var(--font-sans);
  cursor: pointer;
  transition: background var(--transition);
}

.form-submit:hover {
  background: var(--accent-light);
}

.form-message {
  text-align: center;
  margin-top: 16px;
  font-size: 0.9rem;
  min-height: 1.4em;
}

.form-message.success {
  color: #38a169;
  font-weight: 600;
}

/* ---------- FAQ ---------- */
.faq-list {
  max-width: 760px;
  margin: 0 auto;
}

.faq-item {
  background: var(--white);
  border-radius: var(--radius);
  margin-bottom: 12px;
  box-shadow: var(--shadow);
  overflow: hidden;
}

.faq-question {
  display: flex;
  align-items: center;
  justify-content: space-between;
  padding: 20px 24px;
  cursor: pointer;
  gap: 16px;
}

.faq-question h3 {
  font-size: 1rem;
  font-weight: 600;
  color: var(--primary);
  flex: 1;
}

.faq-question .faq-icon {
  width: 24px;
  height: 24px;
  color: var(--text-light);
  transition: transform var(--transition);
  flex-shrink: 0;
}

.faq-item.open .faq-question .faq-icon {
  transform: rotate(180deg);
}

.faq-answer {
  max-height: 0;
  overflow: hidden;
  transition: max-height 0.4s ease;
}

.faq-answer-inner {
  padding: 0 24px 20px;
  font-size: 0.95rem;
  color: var(--text-muted);
  line-height: 1.7;
}

/* ---------- Footer ---------- */
.footer {
  background: var(--primary-dark);
  color: rgba(255,255,255,0.8);
  padding: 60px 0 30px;
}

.footer-grid {
  display: grid;
  grid-template-columns: 2fr 1fr 1fr;
  gap: 40px;
  margin-bottom: 40px;
}

.footer-brand {
  display: flex;
  align-items: center;
  gap: 10px;
  font-weight: 700;
  font-size: 1.1rem;
  color: var(--white);
  margin-bottom: 16px;
}

.footer-brand i {
  width: 24px;
  height: 24px;
  color: var(--accent);
}

.footer-disclaimer {
  font-size: 0.85rem;
  line-height: 1.6;
  opacity: 0.7;
  margin-bottom: 16px;
}

.footer h4 {
  font-size: 0.95rem;
  font-weight: 700;
  color: var(--white);
  margin-bottom: 16px;
}

.footer-links {
  list-style: none;
}

.footer-links li {
  margin-bottom: 10px;
}

.footer-links a {
  font-size: 0.9rem;
  color: rgba(255,255,255,0.7);
  transition: color var(--transition);
}

.footer-links a:hover {
  color: var(--accent);
}

.footer-bottom {
  border-top: 1px solid rgba(255,255,255,0.1);
  padding-top: 24px;
  text-align: center;
  font-size: 0.8rem;
  opacity: 0.6;
}

.footer-editorial {
  background: rgba(255,255,255,0.05);
  border-radius: var(--radius-sm);
  padding: 16px;
  margin-top: 12px;
}

.footer-editorial h4 {
  font-size: 0.85rem;
  margin-bottom: 8px;
}

.footer-editorial p {
  font-size: 0.8rem;
  opacity: 0.7;
  line-height: 1.5;
}

/* ---------- Scroll animations ---------- */
.animate-on-scroll {
  opacity: 0;
  transform: translateY(30px);
  transition: opacity 0.6s ease, transform 0.6s ease;
}

.animate-on-scroll.visible {
  opacity: 1;
  transform: translateY(0);
}

/* ---------- Supporting pages ---------- */
.page-content {
  max-width: 800px;
  margin: 100px auto 60px;
  padding: 0 24px;
}

.page-content h1 {
  font-size: 2rem;
  font-weight: 700;
  color: var(--primary);
  margin-bottom: 8px;
}

.page-content .page-updated {
  font-size: 0.85rem;
  color: var(--text-light);
  margin-bottom: 32px;
}

.page-content h2 {
  font-size: 1.3rem;
  font-weight: 700;
  color: var(--primary);
  margin-top: 32px;
  margin-bottom: 12px;
}

.page-content p {
  font-size: 0.95rem;
  line-height: 1.8;
  color: var(--text);
  margin-bottom: 16px;
}

.page-content ul {
  margin-bottom: 16px;
  padding-left: 24px;
}

.page-content li {
  font-size: 0.95rem;
  line-height: 1.7;
  color: var(--text);
  margin-bottom: 8px;
}

/* ---------- Responsive: 1024px ---------- */
@media (max-width: 1024px) {
  .stats-grid {
    grid-template-columns: repeat(2, 1fr);
  }
  .articles-grid {
    grid-template-columns: 1fr;
  }
  .seasons-grid {
    grid-template-columns: repeat(2, 1fr);
  }
  .footer-grid {
    grid-template-columns: 1fr 1fr;
  }
}

/* ---------- Responsive: 768px ---------- */
@media (max-width: 768px) {
  .nav-toggle {
    display: flex;
  }

  .nav-links {
    position: fixed;
    top: 72px;
    left: 0;
    right: 0;
    background: var(--white);
    flex-direction: column;
    padding: 24px;
    gap: 16px;
    border-bottom: 1px solid var(--border);
    box-shadow: var(--shadow-lg);
    transform: translateY(-120%);
    transition: transform var(--transition);
  }

  .nav-links.active {
    transform: translateY(0);
  }

  .hero h1 {
    font-size: 2rem;
  }

  .hero-subtitle {
    font-size: 1rem;
  }

  .tips-grid {
    grid-template-columns: repeat(2, 1fr);
  }

  .footer-grid {
    grid-template-columns: 1fr;
  }
}

/* ---------- Responsive: 480px ---------- */
@media (max-width: 480px) {
  .hero {
    height: 70vh;
    min-height: 400px;
  }

  .hero h1 {
    font-size: 1.6rem;
  }

  .stats-grid {
    grid-template-columns: 1fr 1fr;
    gap: 12px;
  }

  .tips-grid {
    grid-template-columns: 1fr;
  }

  .seasons-grid {
    grid-template-columns: 1fr;
  }

  .section {
    padding: 48px 0;
  }

  .lead-form {
    padding: 24px;
  }
}