/* ==========================================================
   LANDING PAGE STYLES
   ========================================================== */

/* Navbar */
.landing-nav {
  position: sticky;
  top: 0;
  z-index: 100;
  background: var(--bg-glass);
  backdrop-filter: blur(16px);
  -webkit-backdrop-filter: blur(16px);
  border-bottom: 1px solid var(--border-color);
  padding: 1rem 0;
  transition: all var(--transition-normal);
}

.nav-logo {
  display: flex;
  align-items: center;
  gap: 0.75rem;
  font-family: var(--font-heading);
  font-size: 1.35rem;
  font-weight: 800;
  color: var(--text-main);
}

.nav-logo-icon {
  width: 36px;
  height: 36px;
  background: linear-gradient(135deg, var(--primary), var(--secondary));
  color: #ffffff;
  border-radius: var(--radius-md);
  display: flex;
  align-items: center;
  justify-content: center;
  font-size: 1.1rem;
}

.nav-links {
  display: flex;
  align-items: center;
  gap: 2rem;
  list-style: none;
}

.nav-links a {
  color: var(--text-muted);
  font-weight: 500;
  font-size: 0.95rem;
  transition: color var(--transition-fast);
}

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

/* Hero Section */
.hero-section {
  position: relative;
  padding: 6rem 0 5rem;
  overflow: hidden;
}

.hero-glow {
  position: absolute;
  top: -100px;
  left: 50%;
  transform: translateX(-50%);
  width: 800px;
  height: 500px;
  background: radial-gradient(circle, var(--primary-glow) 0%, rgba(6, 182, 212, 0.1) 50%, transparent 80%);
  filter: blur(80px);
  z-index: -1;
  pointer-events: none;
}

.hero-tag {
  display: inline-flex;
  align-items: center;
  gap: 0.5rem;
  padding: 0.4rem 1rem;
  background: var(--bg-surface);
  border: 1px solid var(--border-color);
  border-radius: var(--radius-full);
  font-size: 0.85rem;
  font-weight: 600;
  color: var(--primary);
  box-shadow: var(--shadow-sm);
  margin-bottom: 1.5rem;
}

.hero-title {
  font-size: 3.5rem;
  font-weight: 800;
  letter-spacing: -0.02em;
  line-height: 1.15;
  margin-bottom: 1.5rem;
}

.hero-gradient-text {
  background: linear-gradient(135deg, var(--primary) 0%, var(--secondary) 100%);
  -webkit-background-clip: text;
  -webkit-text-fill-color: transparent;
}

.hero-subtitle {
  font-size: 1.2rem;
  color: var(--text-muted);
  max-width: 680px;
  margin: 0 auto 2.5rem;
  line-height: 1.6;
}

.hero-cta {
  display: flex;
  align-items: center;
  justify-content: center;
  gap: 1.25rem;
  flex-wrap: wrap;
  margin-bottom: 4rem;
}

/* Stats Counter Bar */
.stats-ticker {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(200px, 1fr));
  gap: 1.5rem;
  padding: 2rem;
  background: var(--bg-surface);
  border: 1px solid var(--border-color);
  border-radius: var(--radius-xl);
  box-shadow: var(--shadow-md);
  margin-top: 2rem;
}

.stat-item {
  text-align: center;
  padding: 0.5rem;
}

.stat-number {
  font-family: var(--font-heading);
  font-size: 2.25rem;
  font-weight: 800;
  color: var(--text-main);
  display: block;
}

.stat-label {
  font-size: 0.875rem;
  color: var(--text-muted);
  font-weight: 500;
}

/* Section Common */
.section {
  padding: 5rem 0;
}

.section-header {
  text-align: center;
  max-width: 650px;
  margin: 0 auto 3.5rem;
}

.section-subtitle {
  text-transform: uppercase;
  letter-spacing: 0.08em;
  font-size: 0.825rem;
  font-weight: 700;
  color: var(--primary);
  margin-bottom: 0.5rem;
  display: block;
}

.section-title {
  font-size: 2.25rem;
  margin-bottom: 1rem;
}

/* Subject Grid */
.subject-grid {
  display: grid;
  grid-template-columns: repeat(auto-fill, minmax(280px, 1fr));
  gap: 1.5rem;
}

.subject-card {
  background: var(--bg-surface);
  border: 1px solid var(--border-color);
  border-radius: var(--radius-lg);
  padding: 1.75rem;
  display: flex;
  flex-direction: column;
  transition: all var(--transition-normal);
  position: relative;
  overflow: hidden;
}

.subject-icon-box {
  width: 52px;
  height: 52px;
  border-radius: var(--radius-md);
  display: flex;
  align-items: center;
  justify-content: center;
  font-size: 1.5rem;
  margin-bottom: 1.25rem;
  color: #ffffff;
}

.subject-meta {
  display: flex;
  align-items: center;
  gap: 1rem;
  margin-top: auto;
  padding-top: 1.25rem;
  border-top: 1px solid var(--border-color);
  font-size: 0.825rem;
  color: var(--text-muted);
}

/* Resource Cards Grid */
.resource-grid {
  display: grid;
  grid-template-columns: repeat(auto-fill, minmax(300px, 1fr));
  gap: 1.5rem;
}

.resource-card {
  background: var(--bg-surface);
  border: 1px solid var(--border-color);
  border-radius: var(--radius-lg);
  overflow: hidden;
  display: flex;
  flex-direction: column;
  transition: all var(--transition-normal);
}

.resource-card-banner {
  height: 140px;
  background: linear-gradient(135deg, #1e1b4b, #312e81);
  padding: 1.25rem;
  display: flex;
  flex-direction: column;
  justify-content: space-between;
  color: #ffffff;
  position: relative;
}

.resource-card-banner.chem { background: linear-gradient(135deg, #083344, #155e75); }
.resource-card-banner.math { background: linear-gradient(135deg, #064e3b, #047857); }
.resource-card-banner.cs { background: linear-gradient(135deg, #451a03, #b45309); }
.resource-card-banner.bio { background: linear-gradient(135deg, #500724, #9d174d); }

.resource-card-body {
  padding: 1.25rem;
  flex: 1;
  display: flex;
  flex-direction: column;
}

.resource-card-footer {
  padding: 1rem 1.25rem;
  border-top: 1px solid var(--border-color);
  background: var(--bg-surface-subtle);
  display: flex;
  align-items: center;
  justify-content: space-between;
}

/* Feature Grid */
.features-grid {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(320px, 1fr));
  gap: 2rem;
}

.feature-box {
  background: var(--bg-surface);
  border: 1px solid var(--border-color);
  border-radius: var(--radius-xl);
  padding: 2.25rem;
  transition: all var(--transition-normal);
}

.feature-icon {
  width: 56px;
  height: 56px;
  border-radius: var(--radius-lg);
  background: var(--primary-light);
  color: var(--primary);
  display: flex;
  align-items: center;
  justify-content: center;
  font-size: 1.5rem;
  margin-bottom: 1.5rem;
}

[data-theme="dark"] .feature-icon {
  background: rgba(79, 70, 229, 0.2);
  color: #a5b4fc;
}

/* FAQ Accordion */
.faq-list {
  max-width: 800px;
  margin: 0 auto;
  display: flex;
  flex-direction: column;
  gap: 1rem;
}

.faq-item {
  background: var(--bg-surface);
  border: 1px solid var(--border-color);
  border-radius: var(--radius-lg);
  overflow: hidden;
  transition: all var(--transition-fast);
}

.faq-header {
  padding: 1.25rem 1.5rem;
  display: flex;
  align-items: center;
  justify-content: space-between;
  cursor: pointer;
  font-family: var(--font-heading);
  font-weight: 600;
  font-size: 1.05rem;
}

.faq-body {
  padding: 0 1.5rem 1.25rem;
  color: var(--text-muted);
  display: none;
  line-height: 1.6;
}

.faq-item.open .faq-body {
  display: block;
}

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

/* Footer */
.site-footer {
  background: var(--bg-surface);
  border-top: 1px solid var(--border-color);
  padding: 5rem 0 2rem;
  margin-top: 4rem;
}

.footer-grid {
  display: grid;
  grid-template-columns: 2fr 1fr 1fr 1fr;
  gap: 3rem;
  margin-bottom: 3rem;
}

.footer-col h4 {
  font-size: 1rem;
  margin-bottom: 1.25rem;
  color: var(--text-main);
}

.footer-col ul {
  list-style: none;
  display: flex;
  flex-direction: column;
  gap: 0.75rem;
}

.footer-col ul a {
  color: var(--text-muted);
  font-size: 0.9rem;
}

.footer-col ul a:hover {
  color: var(--primary);
}

.footer-bottom {
  padding-top: 2rem;
  border-top: 1px solid var(--border-color);
  display: flex;
  align-items: center;
  justify-content: space-between;
  font-size: 0.875rem;
  color: var(--text-muted);
}

@media (max-width: 900px) {
  .hero-title { font-size: 2.5rem; }
  .footer-grid { grid-template-columns: 1fr 1fr; }
  .nav-links { display: none; }
}

@media (max-width: 600px) {
  .hero-title { font-size: 2rem; }
  .footer-grid { grid-template-columns: 1fr; }
  .stats-ticker { grid-template-columns: 1fr 1fr; }
}