/* ============================================
   Assistant Connect AI - Design System
   ============================================ */

/* === CSS Custom Properties === */
:root {
  /* Color Palette */
  --color-primary: #1B4B7F;
  --color-accent: #00D4FF;
  --color-navy: #0A1F3D;
  --color-white: #F8FAFC;
  --color-gray-light: #E2E8F0;
  --color-gray: #64748B;
  --color-dark: #0F172A;
  
  /* Gradients */
  --gradient-primary: linear-gradient(135deg, var(--color-primary) 0%, var(--color-accent) 100%);
  --gradient-hero: linear-gradient(135deg, #0A1F3D 0%, #1B4B7F 50%, #00D4FF 100%);
  --gradient-overlay: linear-gradient(180deg, rgba(10, 31, 61, 0.95) 0%, rgba(27, 75, 127, 0.85) 100%);
  
  /* Spacing Scale */
  --space-xs: 0.5rem;
  --space-sm: 1rem;
  --space-md: 1.5rem;
  --space-lg: 2rem;
  --space-xl: 3rem;
  --space-2xl: 4rem;
  --space-3xl: 6rem;
  
  /* Typography Scale */
  --font-size-sm: 0.875rem;
  --font-size-base: 1rem;
  --font-size-lg: 1.125rem;
  --font-size-xl: 1.25rem;
  --font-size-2xl: 1.5rem;
  --font-size-3xl: 2rem;
  --font-size-4xl: 2.5rem;
  --font-size-5xl: 3rem;
  --font-size-6xl: 4rem;
  
  /* Shadows */
  --shadow-sm: 0 2px 8px rgba(0, 0, 0, 0.1);
  --shadow-md: 0 4px 16px rgba(0, 0, 0, 0.15);
  --shadow-lg: 0 8px 32px rgba(0, 0, 0, 0.2);
  --shadow-glow: 0 0 40px rgba(0, 212, 255, 0.3);
  
  /* Border Radius */
  --radius-sm: 0.5rem;
  --radius-md: 1rem;
  --radius-lg: 1.5rem;
  --radius-full: 9999px;
  
  /* Transitions */
  --transition-fast: 0.2s ease;
  --transition-base: 0.3s ease;
  --transition-slow: 0.5s ease;
}

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

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

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

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

a {
  text-decoration: none;
  color: inherit;
}

ul {
  list-style: none;
}

/* === Typography === */
@import url('https://fonts.googleapis.com/css2?family=Inter:wght@300;400;500;600;700&family=Outfit:wght@600;700;800&display=swap');

h1, h2, h3, h4, h5, h6 {
  font-family: 'Outfit', sans-serif;
  font-weight: 700;
  line-height: 1.2;
  color: var(--color-navy);
}

h1 {
  font-size: var(--font-size-5xl);
  font-weight: 800;
}

h2 {
  font-size: var(--font-size-4xl);
}

h3 {
  font-size: var(--font-size-3xl);
}

p {
  font-size: var(--font-size-lg);
  color: var(--color-gray);
}

/* === Layout Utilities === */
.container {
  max-width: 1200px;
  margin: 0 auto;
  padding: 0 var(--space-lg);
}

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

.section-dark {
  background: var(--color-navy);
  color: var(--color-white);
}

.section-dark h2,
.section-dark h3 {
  color: var(--color-white);
}

.section-dark p {
  color: var(--color-gray-light);
}

/* === Navigation === */
.navbar {
  position: fixed;
  top: 0;
  left: 0;
  right: 0;
  z-index: 1000;
  padding: var(--space-md) 0;
  transition: all var(--transition-base);
}

.navbar.scrolled {
  background: var(--color-dark);
  backdrop-filter: blur(10px);
  box-shadow: var(--shadow-md);
}

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

.logo {
  height: 70px;
  transition: transform var(--transition-base);
}

.logo:hover {
  transform: scale(1.05);
}

.nav-links {
  display: flex;
  gap: var(--space-lg);
  align-items: center;
}

.nav-links a {
  color: var(--color-white);
  font-weight: 500;
  transition: color var(--transition-fast);
  position: relative;
}

.nav-links a::after {
  content: '';
  position: absolute;
  bottom: -4px;
  left: 0;
  width: 0;
  height: 2px;
  background: var(--gradient-primary);
  transition: width var(--transition-base);
}

.nav-links a:hover::after {
  width: 100%;
}

.mobile-menu-toggle {
  display: none;
  background: none;
  border: none;
  color: var(--color-white);
  font-size: var(--font-size-2xl);
  cursor: pointer;
}

/* === Hero Section === */
.hero {
  min-height: 100vh;
  display: flex;
  align-items: center;
  background: var(--gradient-hero);
  position: relative;
  overflow: hidden;
  padding-top: 80px;
}

.hero::before {
  content: '';
  position: absolute;
  top: 0;
  left: 0;
  right: 0;
  bottom: 0;
  background: url('data:image/svg+xml,<svg width="100" height="100" xmlns="http://www.w3.org/2000/svg"><defs><pattern id="grid" width="100" height="100" patternUnits="userSpaceOnUse"><path d="M 100 0 L 0 0 0 100" fill="none" stroke="rgba(255,255,255,0.05)" stroke-width="1"/></pattern></defs><rect width="100%" height="100%" fill="url(%23grid)"/></svg>');
  opacity: 0.3;
}

.hero-content {
  position: relative;
  z-index: 1;
  text-align: center;
  color: var(--color-white);
  animation: fadeInUp 1s ease;
}

.hero h1 {
  color: var(--color-white);
  margin-bottom: var(--space-md);
  font-size: clamp(2.5rem, 5vw, 4.5rem);
}

.hero .subtitle {
  font-size: var(--font-size-xl);
  color: var(--color-gray-light);
  margin-bottom: var(--space-xl);
  max-width: 700px;
  margin-left: auto;
  margin-right: auto;
}

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

/* === Buttons === */
.btn {
  display: inline-block;
  padding: var(--space-md) var(--space-xl);
  border-radius: var(--radius-full);
  font-weight: 600;
  font-size: var(--font-size-lg);
  cursor: pointer;
  transition: all var(--transition-base);
  border: none;
  text-align: center;
}

.btn-primary {
  background: var(--gradient-primary);
  color: var(--color-white);
  box-shadow: var(--shadow-md);
}

.btn-primary:hover {
  transform: translateY(-2px);
  box-shadow: var(--shadow-lg), var(--shadow-glow);
}

.btn-secondary {
  background: rgba(255, 255, 255, 0.1);
  color: var(--color-white);
  border: 2px solid var(--color-white);
  backdrop-filter: blur(10px);
}

.btn-secondary:hover {
  background: rgba(255, 255, 255, 0.2);
  transform: translateY(-2px);
}

/* === Cards === */
.card-grid {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(300px, 1fr));
  gap: var(--space-xl);
  margin-top: var(--space-xl);
}

.card {
  background: rgba(255, 255, 255, 0.05);
  backdrop-filter: blur(10px);
  border-radius: var(--radius-lg);
  padding: var(--space-xl);
  border: 1px solid rgba(255, 255, 255, 0.1);
  transition: all var(--transition-base);
  position: relative;
  overflow: hidden;
}

.card::before {
  content: '';
  position: absolute;
  top: 0;
  left: 0;
  right: 0;
  height: 4px;
  background: var(--gradient-primary);
  transform: scaleX(0);
  transition: transform var(--transition-base);
}

.card:hover::before {
  transform: scaleX(1);
}

.card:hover {
  transform: translateY(-8px);
  box-shadow: var(--shadow-lg);
  border-color: var(--color-accent);
}

.card-light {
  background: var(--color-white);
  border: 1px solid var(--color-gray-light);
}

.card-icon {
  width: 60px;
  height: 60px;
  background: var(--gradient-primary);
  border-radius: var(--radius-md);
  display: flex;
  align-items: center;
  justify-content: center;
  font-size: var(--font-size-3xl);
  margin-bottom: var(--space-md);
  color: var(--color-white);
}

.card h3 {
  margin-bottom: var(--space-sm);
  color: var(--color-white);
}

.card-light h3 {
  color: var(--color-navy);
}

.card p {
  color: var(--color-gray-light);
}

.card-light p {
  color: var(--color-gray);
}

/* === Section Headers === */
.section-header {
  text-align: center;
  margin-bottom: var(--space-2xl);
}

.section-header h2 {
  margin-bottom: var(--space-md);
  position: relative;
  display: inline-block;
}

.section-header h2::after {
  content: '';
  position: absolute;
  bottom: -10px;
  left: 50%;
  transform: translateX(-50%);
  width: 80px;
  height: 4px;
  background: var(--gradient-primary);
  border-radius: var(--radius-full);
}

/* === Features Grid === */
.features-grid {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(250px, 1fr));
  gap: var(--space-lg);
  margin-top: var(--space-xl);
}

.feature-item {
  text-align: center;
  padding: var(--space-lg);
}

.feature-icon {
  font-size: var(--font-size-4xl);
  margin-bottom: var(--space-md);
  background: var(--gradient-primary);
  -webkit-background-clip: text;
  -webkit-text-fill-color: transparent;
  background-clip: text;
}

/* === Steps/Process === */
.steps {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(280px, 1fr));
  gap: var(--space-xl);
  margin-top: var(--space-xl);
  position: relative;
}

.step {
  text-align: center;
  position: relative;
}

.step-number {
  width: 80px;
  height: 80px;
  background: var(--gradient-primary);
  border-radius: 50%;
  display: flex;
  align-items: center;
  justify-content: center;
  font-size: var(--font-size-3xl);
  font-weight: 800;
  color: var(--color-white);
  margin: 0 auto var(--space-md);
  box-shadow: var(--shadow-glow);
}

/* === Contact Form === */
.contact-form-wrapper {
  max-width: 800px;
  margin: 0 auto;
  background: var(--color-white);
  padding: var(--space-2xl);
  border-radius: var(--radius-lg);
  box-shadow: var(--shadow-lg);
}

.contact-form {
  display: flex;
  flex-direction: column;
  gap: var(--space-lg);
}

.form-row {
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: var(--space-lg);
}

.form-group {
  display: flex;
  flex-direction: column;
  gap: var(--space-xs);
}

.form-group label {
  font-weight: 600;
  color: var(--color-navy);
  font-size: var(--font-size-base);
}

.form-group input,
.form-group select,
.form-group textarea {
  padding: var(--space-md);
  border: 2px solid var(--color-gray-light);
  border-radius: var(--radius-sm);
  font-size: var(--font-size-base);
  font-family: 'Inter', sans-serif;
  transition: all var(--transition-base);
  background: var(--color-white);
}

.form-group input:focus,
.form-group select:focus,
.form-group textarea:focus {
  outline: none;
  border-color: var(--color-primary);
  box-shadow: 0 0 0 3px rgba(27, 75, 127, 0.1);
}

.form-group textarea {
  resize: vertical;
  min-height: 120px;
}

.btn-large {
  padding: var(--space-md) var(--space-2xl);
  font-size: var(--font-size-xl);
  width: 100%;
  margin-top: var(--space-md);
}

/* === Form Validation Styles === */
.form-group input.error,
.form-group select.error,
.form-group textarea.error {
  border-color: #EF4444;
  background-color: #FEF2F2;
}

.form-group input.error:focus,
.form-group select.error:focus,
.form-group textarea.error:focus {
  border-color: #DC2626;
  box-shadow: 0 0 0 3px rgba(239, 68, 68, 0.1);
}

.form-group input.success,
.form-group select.success,
.form-group textarea.success {
  border-color: #10B981;
  background-color: #F0FDF4;
}

.form-group input.success:focus,
.form-group select.success:focus,
.form-group textarea.success:focus {
  border-color: #059669;
  box-shadow: 0 0 0 3px rgba(16, 185, 129, 0.1);
}

.error-message {
  color: #DC2626;
  font-size: var(--font-size-sm);
  margin-top: var(--space-xs);
  display: flex;
  align-items: center;
  gap: 0.25rem;
  font-weight: 500;
}

.error-message::before {
  content: '⚠';
  font-size: 1rem;
}

.success-message {
  color: #059669;
  font-size: var(--font-size-sm);
  margin-top: var(--space-xs);
  display: flex;
  align-items: center;
  gap: 0.25rem;
  font-weight: 500;
}

.success-message::before {
  content: '✓';
  font-size: 1rem;
}

/* === Footer === */
.footer {
  background: var(--color-dark);
  color: var(--color-gray-light);
  padding: var(--space-2xl) 0 var(--space-lg);
}

.footer-content {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(250px, 1fr));
  gap: var(--space-xl);
  margin-bottom: var(--space-xl);
}

.footer h4 {
  color: var(--color-white);
  margin-bottom: var(--space-md);
  font-size: var(--font-size-lg);
}

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

.footer-links a {
  color: var(--color-gray-light);
  transition: color var(--transition-fast);
}

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

.footer-bottom {
  text-align: center;
  padding-top: var(--space-lg);
  border-top: 1px solid rgba(255, 255, 255, 0.1);
  color: var(--color-gray);
}

/* === Animations === */
@keyframes fadeInUp {
  from {
    opacity: 0;
    transform: translateY(30px);
  }
  to {
    opacity: 1;
    transform: translateY(0);
  }
}

@keyframes fadeIn {
  from {
    opacity: 0;
  }
  to {
    opacity: 1;
  }
}

@keyframes slideInLeft {
  from {
    opacity: 0;
    transform: translateX(-30px);
  }
  to {
    opacity: 1;
    transform: translateX(0);
  }
}

@keyframes slideInRight {
  from {
    opacity: 0;
    transform: translateX(30px);
  }
  to {
    opacity: 1;
    transform: translateX(0);
  }
}

.animate-on-scroll {
  opacity: 0;
  transform: translateY(30px);
  transition: all 0.6s ease;
}

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

/* === Responsive Design === */
@media (max-width: 768px) {
  :root {
    --font-size-5xl: 2.5rem;
    --font-size-4xl: 2rem;
    --font-size-3xl: 1.75rem;
  }
  
  .nav-links {
    position: fixed;
    top: 0;
    right: -100%;
    height: 100vh;
    width: 70%;
    background: var(--color-navy);
    flex-direction: column;
    justify-content: center;
    transition: right var(--transition-base);
    box-shadow: var(--shadow-lg);
  }
  
  .nav-links.active {
    right: 0;
  }
  
  .mobile-menu-toggle {
    display: block;
  }
  
  .hero-buttons {
    flex-direction: column;
    align-items: center;
  }
  
  .btn {
    width: 100%;
    max-width: 300px;
  }
  
  .section {
    padding: var(--space-2xl) 0;
  }
  
  .card-grid,
  .features-grid,
  .steps {
    grid-template-columns: 1fr;
  }
  
  .form-row {
    grid-template-columns: 1fr;
  }
  
  .contact-form-wrapper {
    padding: var(--space-lg);
  }
}

@media (max-width: 480px) {
  .container {
    padding: 0 var(--space-md);
  }
  
  h1 {
    font-size: var(--font-size-4xl);
  }
  
  h2 {
    font-size: var(--font-size-3xl);
  }
}

/* === Utility Classes === */
.text-center {
  text-align: center;
}

.text-gradient {
  background: var(--gradient-primary);
  -webkit-background-clip: text;
  -webkit-text-fill-color: transparent;
  background-clip: text;
}

.mt-lg {
  margin-top: var(--space-lg);
}

.mb-lg {
  margin-bottom: var(--space-lg);
}