/* ======================================
   LabAutoRun AI - Liquid Glass Design System
   Pure CSS with Glassmorphism Effects
   ====================================== */

/* 1. CSS Custom Properties (Design Tokens) */
:root {
  /* Colors */
  --color-bg-base: #0a0e27;
  --color-bg-secondary: #1a1a3e;
  --color-glass-bg: rgba(255, 255, 255, 0.08);
  --color-glass-border: rgba(255, 255, 255, 0.12);
  --color-text-primary: #ffffff;
  --color-text-secondary: #cbd5e1;
  --color-accent-blue: #3b82f6;
  --color-accent-cyan: #67e8f9;
  --color-accent-purple: #a855f7;
  
  /* Border Radius (Only two values allowed) */
  --rounded-2xl: 16px;
  --rounded-full: 9999px;
  
  /* Glass Effects */
  --blur-amount: blur(20px);
  --glass-saturate: saturate(150%);
  
  /* Easing Functions */
  --ease-out-quart: cubic-bezier(0.165, 0.84, 0.44, 1);
  --ease-in-out-cubic: cubic-bezier(0.645, 0.045, 0.355, 1);
  
  /* Spacing Scale */
  --spacing-xs: 0.5rem;
  --spacing-sm: 1rem;
  --spacing-md: 1.5rem;
  --spacing-lg: 2rem;
  --spacing-xl: 3rem;
  --spacing-2xl: 4rem;
  --spacing-3xl: 6rem;
}

/* 2. Base Styles & Reset */
* {
  margin: 0;
  padding: 0;
  box-sizing: border-box;
}

html {
  scroll-behavior: smooth;
}

body {
  font-family: -apple-system, BlinkMacSystemFont, 'Segoe UI', 'Roboto', 'Oxygen', 'Ubuntu', 'Cantarell', sans-serif;
  background: linear-gradient(135deg, var(--color-bg-base) 0%, var(--color-bg-secondary) 100%);
  background-attachment: fixed;
  color: var(--color-text-primary);
  line-height: 1.6;
  min-height: 100vh;
  overflow-x: hidden;
}

/* 3. Typography */
h1, h2, h3, h4, h5, h6 {
  font-weight: 700;
  line-height: 1.2;
  margin-bottom: 1rem;
}

h1 { font-size: clamp(2rem, 5vw, 3.5rem); }
h2 { font-size: clamp(1.75rem, 4vw, 2.5rem); }
h3 { font-size: clamp(1.25rem, 3vw, 1.75rem); }
h4 { font-size: 1.25rem; }

p {
  margin-bottom: 1rem;
  color: var(--color-text-secondary);
}

a {
  color: var(--color-accent-cyan);
  text-decoration: none;
  transition: color 0.3s var(--ease-out-quart);
}

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

/* 4. Skip Link (Accessibility) */
.skip-link {
  position: absolute;
  top: -40px;
  left: 0;
  background: var(--color-accent-blue);
  color: white;
  padding: 8px;
  z-index: 100;
  border-radius: 0 0 var(--rounded-2xl) 0;
}

.skip-link:focus {
  top: 0;
}

/* 5. Container & Layout */
.container {
  max-width: 1200px;
  margin: 0 auto;
  padding: 0 var(--spacing-md);
}

.section {
  padding: var(--spacing-3xl) 0;
}

/* 6. Glass Components */
.glass-card {
  background: var(--color-glass-bg);
  border: 1px solid var(--color-glass-border);
  border-radius: var(--rounded-2xl);
  backdrop-filter: var(--blur-amount) var(--glass-saturate);
  -webkit-backdrop-filter: var(--blur-amount) var(--glass-saturate);
  padding: var(--spacing-lg);
  transition: all 0.3s var(--ease-out-quart);
}

.glass-card:hover {
  box-shadow: inset 0 0 20px rgba(59, 130, 246, 0.3), 0 8px 32px rgba(0, 0, 0, 0.2);
  border-color: rgba(59, 130, 246, 0.5);
  transform: translateY(-4px);
}

.glass-button {
  display: inline-block;
  background: var(--color-glass-bg);
  border: 1px solid var(--color-glass-border);
  border-radius: var(--rounded-full);
  backdrop-filter: var(--blur-amount);
  -webkit-backdrop-filter: var(--blur-amount);
  padding: 0.75rem 2rem;
  color: var(--color-text-primary);
  font-size: 1rem;
  font-weight: 600;
  cursor: pointer;
  text-align: center;
  transition: all 0.3s var(--ease-out-quart);
}

.glass-button:hover {
  background: rgba(59, 130, 246, 0.2);
  border-color: var(--color-accent-blue);
  box-shadow: 0 0 30px rgba(59, 130, 246, 0.4);
  transform: translateY(-2px);
}

.glass-button:focus {
  outline: 2px solid var(--color-accent-cyan);
  outline-offset: 2px;
}

.glass-button-primary {
  background: linear-gradient(135deg, rgba(59, 130, 246, 0.3), rgba(168, 85, 247, 0.3));
  border-color: var(--color-accent-blue);
}

.glass-button-primary:hover {
  background: linear-gradient(135deg, rgba(59, 130, 246, 0.5), rgba(168, 85, 247, 0.5));
  box-shadow: 0 0 40px rgba(59, 130, 246, 0.6);
}

/* 7. Navigation */
.nav-glass {
  position: fixed;
  top: 0;
  left: 0;
  right: 0;
  z-index: 1000;
  background: rgba(10, 14, 39, 0.8);
  backdrop-filter: var(--blur-amount) var(--glass-saturate);
  -webkit-backdrop-filter: var(--blur-amount) var(--glass-saturate);
  border-bottom: 1px solid var(--color-glass-border);
  padding: var(--spacing-sm) 0;
}

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

.logo-text {
  font-size: 1.5rem;
  font-weight: 700;
  background: linear-gradient(135deg, var(--color-accent-cyan), var(--color-accent-blue));
  -webkit-background-clip: text;
  -webkit-text-fill-color: transparent;
  background-clip: text;
}

.nav-menu {
  display: flex;
  list-style: none;
  gap: var(--spacing-lg);
  align-items: center;
}

.nav-menu a {
  color: var(--color-text-primary);
  font-weight: 500;
  transition: color 0.3s var(--ease-out-quart);
}

.nav-menu a:hover {
  color: var(--color-accent-cyan);
}

.nav-cta {
  padding: 0.5rem 1.5rem;
  background: var(--color-glass-bg);
  border: 1px solid var(--color-glass-border);
  border-radius: var(--rounded-full);
  backdrop-filter: var(--blur-amount);
  -webkit-backdrop-filter: var(--blur-amount);
}

.nav-cta:hover {
  background: rgba(59, 130, 246, 0.2);
  border-color: var(--color-accent-blue);
}

/* 8. Hero Section */
.hero {
  padding: calc(80px + var(--spacing-3xl)) 0 var(--spacing-3xl);
  text-align: center;
  position: relative;
}

.hero::before {
  content: '';
  position: absolute;
  top: 0;
  left: 50%;
  transform: translateX(-50%);
  width: 800px;
  height: 800px;
  background: radial-gradient(circle, rgba(59, 130, 246, 0.15) 0%, transparent 70%);
  pointer-events: none;
  z-index: -1;
}

.hero-content {
  max-width: 800px;
  margin: 0 auto;
}

.hero-title {
  margin-bottom: var(--spacing-md);
  background: linear-gradient(135deg, var(--color-text-primary), var(--color-accent-cyan));
  -webkit-background-clip: text;
  -webkit-text-fill-color: transparent;
  background-clip: text;
}

.hero-subtitle {
  font-size: clamp(1rem, 2vw, 1.25rem);
  color: var(--color-text-secondary);
  margin-bottom: var(--spacing-xl);
  line-height: 1.8;
}

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

/* 9. Section Titles */
.section-title {
  text-align: center;
  margin-bottom: var(--spacing-md);
}

.section-subtitle {
  text-align: center;
  font-size: 1.125rem;
  color: var(--color-text-secondary);
  margin-bottom: var(--spacing-xl);
  max-width: 600px;
  margin-left: auto;
  margin-right: auto;
}

/* 10. Features Grid */
.features-section {
  background: radial-gradient(circle at top right, rgba(168, 85, 247, 0.1) 0%, transparent 50%);
}

.grid-features {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(280px, 1fr));
  gap: var(--spacing-lg);
}

.feature-card {
  text-align: center;
  padding: var(--spacing-xl);
}

.feature-icon {
  font-size: 3rem;
  margin-bottom: var(--spacing-md);
  color: var(--color-accent-cyan);
}

.feature-title {
  margin-bottom: var(--spacing-sm);
  color: var(--color-text-primary);
}

.feature-description {
  font-size: 0.95rem;
  line-height: 1.7;
}

/* 11. How It Works Timeline */
.how-section {
  background: radial-gradient(circle at bottom left, rgba(59, 130, 246, 0.1) 0%, transparent 50%);
}

.timeline {
  max-width: 900px;
  margin: 0 auto;
  display: flex;
  flex-direction: column;
  gap: var(--spacing-lg);
}

.timeline-item {
  display: flex;
  gap: var(--spacing-lg);
  align-items: flex-start;
}

.timeline-icon {
  flex-shrink: 0;
  width: 60px;
  height: 60px;
  display: flex;
  align-items: center;
  justify-content: center;
  font-size: 1.5rem;
  background: var(--color-glass-bg);
  border: 1px solid var(--color-glass-border);
  border-radius: var(--rounded-full);
  color: var(--color-accent-blue);
}

.timeline-content {
  flex: 1;
}

.timeline-title {
  color: var(--color-accent-cyan);
  margin-bottom: var(--spacing-sm);
}

.timeline-description {
  font-size: 0.95rem;
  line-height: 1.7;
}

/* 12. Benefits Grid */
.benefits-section {
  background: radial-gradient(circle at center, rgba(168, 85, 247, 0.08) 0%, transparent 60%);
}

.grid-benefits {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(280px, 1fr));
  gap: var(--spacing-lg);
  margin-bottom: var(--spacing-xl);
}

.benefit-card {
  text-align: center;
  padding: var(--spacing-xl);
}

.stat-number {
  font-size: 4rem;
  font-weight: 700;
  background: linear-gradient(135deg, var(--color-accent-cyan), var(--color-accent-blue));
  -webkit-background-clip: text;
  -webkit-text-fill-color: transparent;
  background-clip: text;
  display: inline-block;
  line-height: 1;
}

.stat-unit {
  font-size: 2rem;
  color: var(--color-accent-cyan);
  display: inline-block;
  margin-left: 0.25rem;
}

.benefit-title {
  margin-top: var(--spacing-md);
  margin-bottom: var(--spacing-sm);
}

.benefit-description {
  font-size: 0.95rem;
}

.benefits-list {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(300px, 1fr));
  gap: var(--spacing-lg);
  margin-top: var(--spacing-xl);
}

.benefit-item {
  padding: var(--spacing-lg);
}

.benefit-item h4 {
  color: var(--color-accent-cyan);
  margin-bottom: var(--spacing-sm);
}

/* 13. CTA Section */
.cta-section {
  padding: var(--spacing-3xl) 0;
}

.cta-card {
  max-width: 800px;
  margin: 0 auto;
  padding: var(--spacing-2xl);
  text-align: center;
  background: linear-gradient(135deg, rgba(59, 130, 246, 0.1), rgba(168, 85, 247, 0.1));
}

.cta-title {
  margin-bottom: var(--spacing-md);
}

.cta-description {
  font-size: 1.125rem;
  margin-bottom: var(--spacing-xl);
  color: var(--color-text-secondary);
}

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

/* 14. Footer */
.footer {
  background: rgba(10, 14, 39, 0.6);
  border-top: 1px solid var(--color-glass-border);
  padding: var(--spacing-xl) 0 var(--spacing-lg);
  margin-top: var(--spacing-3xl);
}

.footer-content {
  display: grid;
  grid-template-columns: 1fr 2fr;
  gap: var(--spacing-xl);
  margin-bottom: var(--spacing-lg);
}

.footer-brand {
  display: flex;
  flex-direction: column;
  gap: var(--spacing-sm);
}

.footer-tagline {
  color: var(--color-text-secondary);
  font-size: 0.9rem;
}

.footer-links {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(150px, 1fr));
  gap: var(--spacing-lg);
}

.footer-column h4 {
  color: var(--color-accent-cyan);
  font-size: 1rem;
  margin-bottom: var(--spacing-sm);
}

.footer-column ul {
  list-style: none;
}

.footer-column li {
  margin-bottom: 0.5rem;
}

.footer-column a {
  color: var(--color-text-secondary);
  font-size: 0.9rem;
  transition: color 0.3s var(--ease-out-quart);
}

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

.footer-bottom {
  text-align: center;
  padding-top: var(--spacing-lg);
  border-top: 1px solid var(--color-glass-border);
  color: var(--color-text-secondary);
  font-size: 0.9rem;
}

/* 15. Animation Utilities */
@keyframes fadeIn {
  from {
    opacity: 0;
    transform: translateY(30px);
  }
  to {
    opacity: 1;
    transform: translateY(0);
  }
}

.fade-in {
  animation: fadeIn 0.8s var(--ease-out-quart) forwards;
}

.animate-on-scroll {
  opacity: 0;
}

/* 16. Responsive Design */
@media (max-width: 768px) {
  .nav-menu {
    gap: var(--spacing-sm);
    font-size: 0.9rem;
  }
  
  .grid-features,
  .grid-benefits,
  .benefits-list {
    grid-template-columns: 1fr;
  }
  
  .timeline-item {
    flex-direction: column;
  }
  
  .footer-content {
    grid-template-columns: 1fr;
  }
  
  .hero-cta,
  .cta-buttons {
    flex-direction: column;
  }
  
  .glass-button {
    width: 100%;
  }
}

@media (max-width: 480px) {
  :root {
    --spacing-xl: 2rem;
    --spacing-2xl: 3rem;
    --spacing-3xl: 4rem;
  }
  
  .hero {
    padding-top: calc(80px + var(--spacing-xl));
  }
  
  .section {
    padding: var(--spacing-xl) 0;
  }
}

/* 17. Focus Styles (Accessibility) */
*:focus-visible {
  outline: 2px solid var(--color-accent-cyan);
  outline-offset: 2px;
  border-radius: 4px;
}

/* 18. Fallback for browsers without backdrop-filter */
@supports not (backdrop-filter: blur(20px)) {
  .glass-card,
  .glass-button,
  .nav-glass,
  .nav-cta {
    background: rgba(255, 255, 255, 0.15);
  }
  
  .glass-button-primary {
    background: rgba(59, 130, 246, 0.4);
  }
}

/* 19. Print Styles */
@media print {
  .nav-glass,
  .skip-link {
    display: none;
  }
  
  body {
    background: white;
    color: black;
  }
}