/* ==================== CSS RESET & VARIABLES ==================== */
:root {
  --emerald-50: #ecfdf5;
  --emerald-500: #10b981;
  --emerald-600: #059669;
  --emerald-700: #047857;
  --purple-500: #a855f7;
  --purple-600: #9333ea;
  --purple-700: #7e22ce;
  --orange-500: #f97316;
  --blue-500: #3b82f6;
  --gray-50: #f9fafb;
  --gray-100: #f3f4f6;
  --gray-200: #e5e7eb;
  --gray-300: #d1d5db;
  --gray-600: #4b5563;
  --gray-700: #374151;
  --gray-800: #1f2937;
  --gray-900: #111827;
}

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

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

body {
  font-family: 'Inter', -apple-system, BlinkMacSystemFont, 'Segoe UI', sans-serif;
  line-height: 1.6;
  color: var(--gray-800);
  background: white;
  -webkit-font-smoothing: antialiased;
}

.container {
  max-width: 1200px;
  margin: 0 auto;
  padding: 0 1.5rem;
}

/* ==================== NAVIGATION ==================== */
.nav {
  position: fixed;
  top: 0;
  left: 0;
  right: 0;
  background: rgba(255, 255, 255, 0.98);
  backdrop-filter: blur(12px);
  border-bottom: 1px solid var(--gray-200);
  z-index: 1000;
  padding: 1rem 0;
}

.nav-content {
  display: flex;
  justify-content: space-between;
  align-items: center;
}

.nav-logo {
  display: flex;
  align-items: center;
  gap: 0.75rem;
  text-decoration: none;
}

.logo-icon {
  width: 32px;
  height: 32px;
  color: var(--emerald-600);
  stroke-width: 2.5;
}

.logo-text {
  font-size: 1.5rem;
  font-weight: 800;
  background: linear-gradient(135deg, var(--emerald-600), var(--purple-600));
  -webkit-background-clip: text;
  -webkit-text-fill-color: transparent;
  background-clip: text;
}

.nav-links {
  display: flex;
  align-items: center;
  gap: 2rem;
}

.nav-link {
  color: var(--gray-700);
  text-decoration: none;
  font-weight: 500;
  font-size: 0.95rem;
  transition: color 0.2s;
}

.nav-link:hover {
  color: var(--emerald-600);
}

/* ==================== BUTTONS ==================== */
.btn {
  display: inline-flex;
  align-items: center;
  gap: 0.5rem;
  padding: 0.875rem 1.75rem;
  border-radius: 12px;
  font-weight: 600;
  font-size: 0.95rem;
  text-decoration: none;
  transition: all 0.3s ease;
  border: 2px solid transparent;
  cursor: pointer;
}

.btn svg {
  width: 18px;
  height: 18px;
  stroke-width: 2.5;
}

.btn-primary {
  background: linear-gradient(135deg, var(--emerald-600), var(--emerald-700));
  color: white;
  box-shadow: 0 4px 6px -1px rgba(16, 185, 129, 0.3);
}

.btn-primary:hover {
  transform: translateY(-2px);
  box-shadow: 0 10px 15px -3px rgba(16, 185, 129, 0.4);
}

.btn-hero {
  background: linear-gradient(135deg, var(--emerald-600), var(--purple-600));
  color: white;
  padding: 1.125rem 2.25rem;
  font-size: 1.05rem;
  box-shadow: 0 10px 25px -5px rgba(16, 185, 129, 0.4);
}

.btn-hero:hover {
  transform: translateY(-3px);
  box-shadow: 0 20px 25px -5px rgba(16, 185, 129, 0.5);
}

.btn-secondary {
  border: 2px solid var(--emerald-600);
  color: var(--emerald-600);
  background: white;
}

.btn-secondary:hover {
  background: var(--emerald-600);
  color: white;
}

.btn-cta {
  background: white;
  color: var(--emerald-600);
  padding: 1.125rem 2.25rem;
  font-size: 1.05rem;
  box-shadow: 0 10px 25px -5px rgba(0, 0, 0, 0.2);
}

.btn-cta:hover {
  transform: translateY(-3px);
  box-shadow: 0 20px 25px -5px rgba(0, 0, 0, 0.3);
}

.btn-pricing {
  width: 100%;
  justify-content: center;
  background: var(--gray-100);
  color: var(--gray-700);
  border-color: var(--gray-300);
}

.btn-pricing:hover {
  background: var(--gray-200);
  border-color: var(--gray-400);
}

.btn-pricing-featured {
  width: 100%;
  justify-content: center;
  background: linear-gradient(135deg, var(--emerald-600), var(--purple-600));
  color: white;
  box-shadow: 0 10px 25px -5px rgba(16, 185, 129, 0.4);
}

.btn-pricing-featured:hover {
  transform: translateY(-3px);
  box-shadow: 0 20px 25px -5px rgba(16, 185, 129, 0.5);
}

/* ==================== TYPOGRAPHY ==================== */
.gradient-text {
  background: linear-gradient(135deg, var(--emerald-600), var(--purple-600));
  -webkit-background-clip: text;
  -webkit-text-fill-color: transparent;
  background-clip: text;
}

/* ==================== HERO SECTION ==================== */
.hero {
  padding: 9rem 0 6rem;
  background: linear-gradient(135deg, rgba(16, 185, 129, 0.03), rgba(168, 85, 247, 0.03));
  border-bottom: 1px solid var(--gray-200);
}

.hero-grid {
  display: grid;
  grid-template-columns: 1.1fr 0.9fr;
  gap: 4rem;
  align-items: center;
}

.hero-content {
  display: flex;
  flex-direction: column;
  gap: 1.75rem;
}

.badge {
  display: inline-flex;
  align-items: center;
  gap: 0.5rem;
  padding: 0.5rem 1.25rem;
  background: var(--emerald-50);
  border: 1px solid var(--emerald-500);
  border-radius: 100px;
  color: var(--emerald-700);
  font-weight: 600;
  font-size: 0.9rem;
  width: fit-content;
}

.badge-icon {
  width: 18px;
  height: 18px;
  color: var(--emerald-600);
  stroke-width: 2.5;
}

.hero-title {
  font-size: 3.5rem;
  font-weight: 900;
  line-height: 1.1;
  color: var(--gray-900);
  letter-spacing: -0.02em;
}

.hero-description {
  font-size: 1.25rem;
  color: var(--gray-600);
  line-height: 1.7;
  max-width: 90%;
}

.hero-cta {
  display: flex;
  gap: 1rem;
  flex-wrap: wrap;
  margin-top: 0.5rem;
}

.hero-trust {
  display: flex;
  gap: 2rem;
  flex-wrap: wrap;
  margin-top: 0.5rem;
}

.trust-item {
  display: flex;
  align-items: center;
  gap: 0.5rem;
  color: var(--gray-600);
  font-size: 0.9rem;
}

.check-icon {
  width: 20px;
  height: 20px;
  color: var(--emerald-600);
  stroke-width: 2.5;
}

.hero-visual {
  position: relative;
}

.demo-card {
  background: white;
  border-radius: 20px;
  padding: 2rem;
  box-shadow: 0 20px 25px -5px rgba(0, 0, 0, 0.1), 0 10px 10px -5px rgba(0, 0, 0, 0.04);
  border: 1px solid var(--gray-200);
}

.demo-header {
  display: flex;
  align-items: center;
  gap: 0.75rem;
  margin-bottom: 1.5rem;
  padding-bottom: 1rem;
  border-bottom: 2px solid var(--gray-100);
}

.demo-icon {
  width: 24px;
  height: 24px;
  color: var(--emerald-600);
  stroke-width: 2.5;
}

.demo-sessions {
  display: flex;
  flex-direction: column;
  gap: 0.75rem;
}

.session {
  display: flex;
  align-items: center;
  gap: 1rem;
  padding: 1rem;
  border-radius: 12px;
  border: 2px solid;
}

.session-emerald {
  background: rgba(16, 185, 129, 0.1);
  border-color: var(--emerald-500);
}

.session-purple {
  background: rgba(168, 85, 247, 0.1);
  border-color: var(--purple-500);
}

.session-orange {
  background: rgba(249, 115, 22, 0.1);
  border-color: var(--orange-500);
}

.session-time {
  font-size: 0.85rem;
  font-weight: 700;
  min-width: 70px;
}

.session-info {
  flex: 1;
}

.session-student {
  font-weight: 600;
  font-size: 0.95rem;
  margin-bottom: 0.1rem;
}

.session-subject {
  font-size: 0.8rem;
  opacity: 0.7;
}

/* ==================== SECTIONS ==================== */
.features,
.benefits,
.pricing,
.cta {
  padding: 6rem 0;
}

.section-header {
  text-align: center;
  margin-bottom: 4rem;
}

.section-title {
  font-size: 2.75rem;
  font-weight: 900;
  color: var(--gray-900);
  margin-bottom: 1rem;
  letter-spacing: -0.02em;
}

.section-description {
  font-size: 1.2rem;
  color: var(--gray-600);
  max-width: 650px;
  margin: 0 auto;
  line-height: 1.7;
}

.section-title-white {
  color: white;
}

.section-description-white {
  color: rgba(255, 255, 255, 0.9);
}

/* ==================== FEATURES ==================== */
.features {
  background: white;
}

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

.feature-card {
  background: white;
  border: 2px solid var(--gray-200);
  border-radius: 20px;
  padding: 2.25rem;
  transition: all 0.3s ease;
}

.feature-card:hover {
  transform: translateY(-6px);
  box-shadow: 0 20px 25px -5px rgba(0, 0, 0, 0.1);
  border-color: var(--emerald-500);
}

.feature-icon {
  width: 48px;
  height: 48px;
  margin-bottom: 1.25rem;
  stroke-width: 2;
}

.feature-icon-emerald {
  color: var(--emerald-600);
}

.feature-icon-purple {
  color: var(--purple-600);
}

.feature-icon-blue {
  color: var(--blue-500);
}

.feature-icon-orange {
  color: var(--orange-500);
}

.feature-title {
  font-size: 1.35rem;
  font-weight: 700;
  color: var(--gray-900);
  margin-bottom: 0.75rem;
}

.feature-description {
  font-size: 1rem;
  color: var(--gray-600);
  line-height: 1.7;
}

/* ==================== BENEFITS ==================== */
.benefits {
  background: linear-gradient(135deg, rgba(16, 185, 129, 0.03), rgba(168, 85, 247, 0.03));
}

.benefits-grid {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(280px, 1fr));
  gap: 3rem;
}

.benefit-card {
  text-align: center;
}

.benefit-stat {
  font-size: 4.5rem;
  font-weight: 900;
  background: linear-gradient(135deg, var(--emerald-600), var(--purple-600));
  -webkit-background-clip: text;
  -webkit-text-fill-color: transparent;
  background-clip: text;
  line-height: 1;
  margin-bottom: 1rem;
}

.benefit-label {
  font-size: 1.5rem;
  font-weight: 700;
  color: var(--gray-900);
  margin-bottom: 0.5rem;
}

.benefit-description {
  font-size: 1rem;
  color: var(--gray-600);
}

/* ==================== PRICING ==================== */
.pricing {
  background: white;
}

.pricing-grid {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(300px, 1fr));
  gap: 2rem;
  max-width: 1100px;
  margin: 0 auto;
}

.pricing-card {
  background: white;
  border: 2px solid var(--gray-200);
  border-radius: 24px;
  padding: 2.5rem;
  text-align: center;
  position: relative;
  transition: all 0.3s ease;
}

.pricing-card:hover {
  transform: translateY(-8px);
  box-shadow: 0 20px 25px -5px rgba(0, 0, 0, 0.1);
}

.pricing-card-featured {
  border-width: 3px;
  border-color: var(--emerald-600);
  box-shadow: 0 10px 25px -5px rgba(16, 185, 129, 0.2);
  transform: scale(1.03);
}

.pricing-badge {
  position: absolute;
  top: -14px;
  left: 50%;
  transform: translateX(-50%);
  background: linear-gradient(135deg, var(--emerald-600), var(--purple-600));
  color: white;
  padding: 0.5rem 1.5rem;
  border-radius: 100px;
  font-size: 0.85rem;
  font-weight: 700;
  letter-spacing: 0.025em;
}

.pricing-name {
  font-size: 1.5rem;
  font-weight: 700;
  color: var(--gray-900);
  margin-bottom: 1rem;
}

.pricing-price {
  margin: 1.5rem 0;
}

.price-currency {
  font-size: 1.5rem;
  font-weight: 700;
  color: var(--gray-600);
  vertical-align: super;
}

.price-amount {
  font-size: 4rem;
  font-weight: 900;
  background: linear-gradient(135deg, var(--emerald-600), var(--purple-600));
  -webkit-background-clip: text;
  -webkit-text-fill-color: transparent;
  background-clip: text;
  line-height: 1;
}

.price-period {
  font-size: 1.1rem;
  color: var(--gray-600);
}

.pricing-description {
  color: var(--gray-600);
  margin-bottom: 2rem;
  font-size: 1rem;
}

.pricing-features {
  list-style: none;
  margin: 2rem 0;
  text-align: left;
}

.pricing-features li {
  display: flex;
  align-items: center;
  gap: 0.75rem;
  padding: 0.75rem 0;
  color: var(--gray-700);
  font-size: 0.95rem;
}

.pricing-features li::before {
  content: '✓';
  color: var(--emerald-600);
  font-weight: 900;
  font-size: 1.2rem;
  flex-shrink: 0;
}

.pricing-note {
  font-size: 0.85rem;
  color: var(--gray-500);
  margin-top: 1.5rem;
  font-style: italic;
}

/* ==================== CTA SECTION ==================== */
.cta {
  background: linear-gradient(135deg, var(--emerald-600), var(--purple-600));
  color: white;
}

.cta-content {
  text-align: center;
  max-width: 800px;
  margin: 0 auto;
}

.cta-title {
  font-size: 3rem;
  font-weight: 900;
  margin-bottom: 1rem;
  color: white;
}

.cta-description {
  font-size: 1.25rem;
  margin-bottom: 2.5rem;
  color: rgba(255, 255, 255, 0.95);
  line-height: 1.7;
}

.cta-note {
  font-size: 0.95rem;
  color: rgba(255, 255, 255, 0.8);
  margin-top: 1.5rem;
}

/* ==================== FOOTER ==================== */
.footer {
  background: var(--gray-900);
  color: var(--gray-400);
  padding: 4rem 0 2rem;
}

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

.footer-brand {
  display: flex;
  flex-direction: column;
  gap: 1rem;
}

.footer-logo {
  font-size: 1.5rem;
  font-weight: 800;
  background: linear-gradient(135deg, var(--emerald-500), var(--purple-500));
  -webkit-background-clip: text;
  -webkit-text-fill-color: transparent;
  background-clip: text;
}

.footer-tagline {
  color: var(--gray-500);
  font-size: 0.95rem;
  line-height: 1.6;
}

.footer-heading {
  color: white;
  font-size: 1.05rem;
  font-weight: 700;
  margin-bottom: 1.25rem;
}

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

.footer-links a {
  color: var(--gray-400);
  text-decoration: none;
  font-size: 0.9rem;
  transition: color 0.2s;
}

.footer-links a:hover {
  color: var(--emerald-500);
}

.footer-bottom {
  border-top: 1px solid var(--gray-800);
  padding-top: 2rem;
  text-align: center;
  color: var(--gray-500);
  font-size: 0.9rem;
}

/* ==================== STAT CARDS (if used) ==================== */
.stat-card {
  display: flex;
  align-items: center;
  gap: 1.5rem;
  padding: 2rem;
  background: white;
  border-radius: 16px;
  border: 2px solid var(--gray-200);
}

.stat-icon {
  width: 48px;
  height: 48px;
  color: var(--emerald-600);
}

.stat-content {
  flex: 1;
}

.stat-value {
  font-size: 2.5rem;
  font-weight: 900;
  color: var(--gray-900);
  line-height: 1;
  margin-bottom: 0.25rem;
}

.stat-label {
  font-size: 1rem;
  color: var(--gray-600);
}

/* ==================== RESPONSIVE DESIGN ==================== */
@media (max-width: 1024px) {
  .hero-grid {
    grid-template-columns: 1fr;
    gap: 3rem;
  }

  .hero-visual {
    order: -1;
  }

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

@media (max-width: 768px) {
  html {
    font-size: 14px;
  }

  .hero {
    padding: 7rem 0 4rem;
  }

  .hero-title {
    font-size: 2.5rem;
  }

  .hero-description {
    font-size: 1.1rem;
    max-width: 100%;
  }

  .nav-links {
    gap: 1rem;
  }

  .nav-link {
    display: none;
  }

  .features,
  .benefits,
  .pricing,
  .cta {
    padding: 4rem 0;
  }

  .section-title {
    font-size: 2rem;
  }

  .section-description {
    font-size: 1.05rem;
  }

  .features-grid,
  .pricing-grid {
    grid-template-columns: 1fr;
  }

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

  .cta-title {
    font-size: 2.25rem;
  }

  .hero-cta {
    flex-direction: column;
  }

  .btn {
    width: 100%;
    justify-content: center;
  }
}

@media (max-width: 480px) {
  .hero-title {
    font-size: 2rem;
  }

  .section-title {
    font-size: 1.75rem;
  }

  .benefit-stat {
    font-size: 3.5rem;
  }

  .price-amount {
    font-size: 3rem;
  }

  .demo-card {
    padding: 1.5rem;
  }
}