/* Nexus Precision Evolved - DriveDue Light Theme Design System */
:root {
  /* Colors */
  --primary: #3b82f6;
  --on-primary: #ffffff;
  --primary-container: #dbeafe;
  --on-primary-container: #1e40af;
  --secondary: #1f2937;
  --on-secondary: #f9fafb;
  --secondary-container: #f3f4f6;
  --on-secondary-container: #111827;
  --background: #f9fafb;
  --on-background: #111827;
  --surface: #ffffff;
  --surface-variant: #f3f4f6;
  --on-surface: #111827;
  --on-surface-variant: #4b5563;
  --outline: #9ca3af;
  --outline-variant: #d1d5db;

  /* Typography */
  --display-lg: 48px / 56px 'Inter', sans-serif;
  --display-lg-mobile: 32px / 40px 'Inter', sans-serif;
  --headline-lg: 32px / 40px 'Inter', sans-serif;
  --headline-lg-mobile: 24px / 32px 'Inter', sans-serif;
  --headline-md: 24px / 32px 'Inter', sans-serif;
  --body-lg: 18px / 28px 'Inter', sans-serif;
  --body-md: 16px / 24px 'Inter', sans-serif;
  --label-md: 14px / 20px 'Inter', sans-serif;
  --label-sm: 12px / 16px 'Inter', sans-serif;

  /* Spacing */
  --base: 8px;
  --xs: 4px;
  --sm: 12px;
  --md: 24px;
  --lg: 40px;
  --xl: 64px;
  --gutter: 24px;
  --margin-mobile: 16px;
  --margin-desktop: 48px;

  /* Border Radius */
  --rounded-sm: 0.25rem;
  --rounded: 0.5rem;
  --rounded-md: 0.75rem;
  --rounded-lg: 1rem;
  --rounded-xl: 1.5rem;
  --rounded-full: 9999px;
}

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

body {
  font-family: 'Inter', -apple-system, BlinkMacSystemFont, 'Segoe UI', sans-serif;
  background-color: var(--background);
  color: var(--on-background);
  line-height: 1.6;
  overflow-x: hidden;
}

.container {
  max-width: 1200px;
  margin: 0 auto;
  padding: 0 var(--md);
}

.header {
  position: sticky;
  top: 0;
  z-index: 1000;
  background: rgba(255, 255, 255, 0.95);
  backdrop-filter: blur(12px);
  border-bottom: 1px solid var(--outline-variant);
}

.header-content {
  display: flex;
  align-items: center;
  justify-content: space-between;
  padding: var(--sm) 0;
}

.logo {
  font: var(--headline-md);
  font-weight: 800;
  color: var(--primary);
  text-decoration: none;
  letter-spacing: -0.02em;
}

.nav {
  display: flex;
  gap: var(--lg);
}

.nav-link {
  color: var(--on-surface-variant);
  text-decoration: none;
  font: var(--label-md);
  font-weight: 600;
  transition: color 0.3s ease;
}

.nav-link:hover,
.nav-link.active {
  color: var(--primary);
}

.header-actions {
  display: flex;
  gap: var(--md);
  align-items: center;
}

.back-link {
  color: var(--on-surface-variant);
  text-decoration: none;
  font: var(--label-md);
  font-weight: 500;
  transition: color 0.3s ease;
}

.back-link:hover {
  color: var(--primary);
}

.cta-button {
  background: linear-gradient(135deg, var(--primary) 0%, #2563eb 100%);
  color: var(--on-primary);
  padding: var(--sm) var(--md);
  border-radius: var(--rounded-lg);
  text-decoration: none;
  font: var(--label-md);
  font-weight: 700;
  box-shadow: 0 4px 14px rgba(59, 130, 246, 0.25);
  transition: transform 0.3s ease, box-shadow 0.3s ease;
}

.cta-button:hover {
  transform: translateY(-2px);
  box-shadow: 0 8px 20px rgba(59, 130, 246, 0.35);
}

.hero {
  background: 
    linear-gradient(135deg, rgba(30, 58, 138, 0.7) 0%, rgba(15, 23, 42, 0.75) 100%),
    url('https://images.unsplash.com/photo-1492144534655-ae79c964c9d7?q=80&w=2070&auto=format&fit=crop');
  background-size: cover;
  background-position: center;
  padding: 100px 0;
  text-align: center;
  position: relative;
  overflow: hidden;
}

.hero::before {
  content: '';
  position: absolute;
  top: -50%;
  left: -50%;
  width: 200%;
  height: 200%;
  background: radial-gradient(circle at 30% 20%, rgba(59, 130, 246, 0.2) 0%, transparent 50%);
  pointer-events: none;
}

.hero-content {
  max-width: 900px;
  margin: 0 auto;
  position: relative;
  z-index: 1;
  padding: 0 var(--sm);
}

.hero-badge {
  display: inline-block;
  background: rgba(255, 255, 255, 0.2);
  color: #fff;
  padding: var(--xs) var(--md);
  border-radius: var(--rounded-full);
  font: var(--label-sm);
  font-weight: 600;
  letter-spacing: 0.02em;
  margin-bottom: var(--md);
  border: 1px solid rgba(255, 255, 255, 0.3);
  backdrop-filter: blur(8px);
  box-shadow: 0 2px 8px rgba(0, 0, 0, 0.2);
}

.hero-title {
  font: var(--display-lg);
  font-weight: 700;
  color: #fff;
  margin-bottom: var(--md);
  letter-spacing: -0.02em;
  text-shadow: 0 2px 8px rgba(0, 0, 0, 0.3);
}

.hero-subtitle {
  font: var(--body-lg);
  color: rgba(255, 255, 255, 0.9);
  margin-bottom: var(--lg);
  line-height: 1.7;
  text-shadow: 0 2px 6px rgba(0, 0, 0, 0.3);
}

.hero-buttons {
  display: flex;
  gap: var(--md);
  justify-content: center;
  flex-wrap: wrap;
}

.cta-primary {
  background: linear-gradient(135deg, #fff 0%, #e0f2fe 100%);
  color: var(--primary);
  padding: var(--md) var(--lg);
  border-radius: var(--rounded-lg);
  text-decoration: none;
  font: var(--body-md);
  font-weight: 700;
  box-shadow: 0 4px 14px rgba(0, 0, 0, 0.25);
  transition: transform 0.3s ease, box-shadow 0.3s ease;
}

.cta-primary:hover {
  transform: translateY(-2px);
  box-shadow: 0 8px 20px rgba(0, 0, 0, 0.35);
}

.cta-secondary {
  background: rgba(255, 255, 255, 0.15);
  color: #fff;
  padding: var(--md) var(--lg);
  border-radius: var(--rounded-lg);
  text-decoration: none;
  font: var(--body-md);
  font-weight: 700;
  border: 1px solid rgba(255, 255, 255, 0.4);
  backdrop-filter: blur(8px);
  box-shadow: 0 2px 8px rgba(0, 0, 0, 0.2);
  transition: background 0.3s ease, transform 0.3s ease, box-shadow 0.3s ease;
}

.cta-secondary:hover {
  background: rgba(255, 255, 255, 0.25);
  transform: translateY(-2px);
  box-shadow: 0 4px 14px rgba(0, 0, 0, 0.25);
}

.features {
  padding: var(--lg) 0;
  position: relative;
}

.section-title {
  font: var(--headline-lg);
  font-weight: 700;
  color: var(--on-background);
  margin-bottom: var(--lg);
  text-align: center;
  letter-spacing: -0.01em;
}

.features-grid {
  display: grid;
  grid-template-columns: repeat(3, 1fr);
  gap: var(--md);
}

.feature-card {
  background: var(--surface);
  padding: var(--lg);
  border-radius: var(--rounded-xl);
  border: 1px solid var(--outline-variant);
  box-shadow: 0 4px 14px rgba(0, 0, 0, 0.06);
  transition: transform 0.3s ease, box-shadow 0.3s ease, border-color 0.3s ease;
}

.feature-card:hover {
  transform: translateY(-4px);
  box-shadow: 0 8px 20px rgba(0, 0, 0, 0.1);
  border-color: var(--primary);
}

.feature-icon {
  font-size: 40px;
  margin-bottom: var(--md);
  filter: drop-shadow(0 0 10px rgba(59, 130, 246, 0.2));
}

.feature-title {
  font: var(--headline-md);
  font-weight: 700;
  color: var(--on-background);
  margin-bottom: var(--sm);
}

.feature-desc {
  font: var(--body-md);
  color: var(--on-surface-variant);
  line-height: 1.7;
}

.how-it-works {
  padding: var(--lg) 0;
  position: relative;
  background: var(--surface-variant);
}

.steps {
  display: grid;
  grid-template-columns: repeat(3, 1fr);
  gap: var(--md);
  position: relative;
  z-index: 1;
}

.step {
  background: var(--surface);
  padding: var(--lg);
  border-radius: var(--rounded-xl);
  border: 1px solid var(--outline-variant);
  text-align: center;
  box-shadow: 0 4px 14px rgba(0, 0, 0, 0.06);
}

.step-number {
  width: 70px;
  height: 70px;
  background: linear-gradient(135deg, var(--primary) 0%, #2563eb 100%);
  color: var(--on-primary);
  border-radius: var(--rounded-full);
  display: flex;
  align-items: center;
  justify-content: center;
  font: var(--headline-lg);
  font-weight: 800;
  margin: 0 auto var(--md);
  box-shadow: 0 4px 14px rgba(59, 130, 246, 0.25);
}

.step-title {
  font: var(--headline-md);
  font-weight: 700;
  color: var(--on-background);
  margin-bottom: var(--sm);
}

.step-desc {
  font: var(--body-md);
  color: var(--on-surface-variant);
  line-height: 1.7;
}

.download-section {
  padding: var(--lg) 0;
  position: relative;
}

.download-content {
  text-align: center;
}

.download-subtitle {
  font: var(--body-lg);
  color: var(--on-surface-variant);
  margin-bottom: var(--lg);
}

.download-buttons {
  display: flex;
  gap: var(--md);
  justify-content: center;
  flex-wrap: wrap;
}

.download-button {
  display: inline-flex;
  align-items: center;
  gap: 12px;
  background: #000;
  color: #fff;
  padding: 12px 24px;
  border-radius: 10px;
  text-decoration: none;
  transition: transform 0.2s ease, opacity 0.2s ease;
  border: 1px solid #333;
  min-width: 180px;
  justify-content: center;
}

.download-button:hover {
  transform: translateY(-2px);
  opacity: 0.9;
}

.store-icon {
  width: 32px;
  height: 32px;
  flex-shrink: 0;
}

.app-store .store-icon {
  color: #fff;
}

.play-store .store-icon {
  color: #fff;
}

.store-text {
  display: flex;
  flex-direction: column;
  align-items: flex-start;
  text-align: left;
}

.store-label {
  font-size: 11px;
  line-height: 1.2;
  font-weight: 400;
  opacity: 0.9;
  font-family: -apple-system, BlinkMacSystemFont, 'Segoe UI', Roboto, Oxygen, Ubuntu, Cantarell, sans-serif;
  text-transform: uppercase;
  letter-spacing: 0.5px;
}

.store-name {
  font-size: 20px;
  line-height: 1.2;
  font-weight: 600;
  font-family: -apple-system, BlinkMacSystemFont, 'Segoe UI', Roboto, Oxygen, Ubuntu, Cantarell, sans-serif;
}

@media (max-width: 640px) {
  .download-buttons {
    flex-direction: column;
  }

  .download-button {
    width: 100%;
    max-width: 280px;
    margin: 0 auto;
  }
}

.cta-section {
  padding: var(--lg) 0;
  position: relative;
}

.cta-content {
  background: linear-gradient(135deg, #dbeafe 0%, #eff6ff 100%);
  padding: var(--lg);
  border-radius: var(--rounded-xl);
  border: 1px solid var(--outline-variant);
  text-align: center;
  box-shadow: 0 4px 14px rgba(0, 0, 0, 0.06);
}

.cta-title {
  font: var(--headline-lg);
  font-weight: 700;
  color: var(--on-background);
  margin-bottom: var(--sm);
}

.cta-text {
  font: var(--body-lg);
  color: var(--on-surface-variant);
  margin-bottom: var(--lg);
}

.cta-button-large {
  display: inline-block;
  background: linear-gradient(135deg, var(--primary) 0%, #2563eb 100%);
  color: var(--on-primary);
  padding: var(--md) var(--lg);
  border-radius: var(--rounded-lg);
  text-decoration: none;
  font: var(--body-md);
  font-weight: 700;
  box-shadow: 0 4px 14px rgba(59, 130, 246, 0.25);
  transition: transform 0.3s ease, box-shadow 0.3s ease;
}

.cta-button-large:hover {
  transform: translateY(-2px);
  box-shadow: 0 8px 20px rgba(59, 130, 246, 0.35);
}

.contact {
  padding: var(--lg) 0;
  position: relative;
}

.contact-form {
  background: var(--surface);
  padding: var(--lg);
  border-radius: var(--rounded-xl);
  border: 1px solid var(--outline-variant);
  max-width: 700px;
  margin: 0 auto;
  box-shadow: 0 4px 14px rgba(0, 0, 0, 0.06);
}

.form-row {
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: var(--md);
  margin-bottom: var(--md);
}

.form-input,
.form-textarea {
  width: 100%;
  padding: var(--md);
  background-color: var(--surface-variant);
  border: 1px solid var(--outline-variant);
  border-radius: var(--rounded-lg);
  font: var(--body-md);
  font-family: 'Inter', sans-serif;
  color: var(--on-background);
  transition: border-color 0.3s ease, box-shadow 0.3s ease;
}

.form-input::placeholder,
.form-textarea::placeholder {
  color: var(--outline);
}

.form-input:focus,
.form-textarea:focus {
  outline: none;
  border-color: var(--primary);
  box-shadow: 0 0 0 3px rgba(59, 130, 246, 0.15);
}

.form-textarea {
  min-height: 140px;
  resize: vertical;
  margin-bottom: var(--md);
}

.submit-button {
  width: 100%;
  background: linear-gradient(135deg, var(--primary) 0%, #2563eb 100%);
  color: var(--on-primary);
  padding: var(--md) var(--lg);
  border: none;
  border-radius: var(--rounded-lg);
  font: var(--body-md);
  font-weight: 700;
  cursor: pointer;
  box-shadow: 0 4px 14px rgba(59, 130, 246, 0.25);
  transition: transform 0.3s ease, box-shadow 0.3s ease;
}

.submit-button:hover {
  transform: translateY(-2px);
  box-shadow: 0 8px 20px rgba(59, 130, 246, 0.35);
}

.footer {
  background-color: var(--surface);
  padding: var(--lg) 0;
  border-top: 1px solid var(--outline-variant);
}

.footer-content {
  text-align: center;
}

.footer-copyright {
  font: var(--label-md);
  color: var(--on-surface-variant);
  margin-bottom: var(--md);
}

.footer-nav {
  display: flex;
  gap: var(--md);
  justify-content: center;
  flex-wrap: wrap;
}

.footer-link {
  color: var(--on-surface-variant);
  text-decoration: none;
  font: var(--label-md);
  transition: color 0.3s ease;
}

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

@media (max-width: 968px) {
  .nav {
    display: none;
  }

  .back-link {
    display: none;
  }

  .hero {
    padding: 80px 0;
  }

  .hero-title {
    font: var(--display-lg-mobile);
  }

  .section-title {
    font: var(--headline-lg-mobile);
  }

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

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

  .form-row {
    grid-template-columns: 1fr;
  }
}

@media (max-width: 640px) {
  .container {
    padding: 0 var(--sm);
  }

  .header-content {
    padding: var(--sm) 0;
    gap: var(--sm);
  }

  .logo {
    font-size: 18px;
  }

  .cta-button {
    padding: 8px 16px;
    font-size: 13px;
  }

  .hero {
    padding: 60px 0;
  }

  .hero-badge {
    margin-bottom: var(--sm);
  }

  .hero-title {
    font: var(--display-lg-mobile);
    margin-bottom: var(--sm);
  }

  .hero-subtitle {
    font-size: 16px;
    margin-bottom: var(--md);
  }

  .hero-buttons {
    gap: var(--sm);
  }

  .cta-primary, .cta-secondary {
    padding: var(--sm) var(--lg);
    font-size: 14px;
    width: 100%;
  }

  .section-title {
    font: var(--headline-lg-mobile);
    margin-bottom: var(--md);
  }

  .features-grid {
    grid-template-columns: 1fr;
    gap: var(--sm);
  }

  .feature-card, .step, .pricing-card, .faq-item, .cta-content, .contact-form {
    padding: var(--md);
  }

  .feature-icon {
    font-size: 32px;
    margin-bottom: var(--sm);
  }

  .step-number {
    width: 60px;
    height: 60px;
    font-size: 24px;
  }

  .form-input, .form-textarea {
    padding: var(--sm);
  }
}