/* Dark Theme Variables
 * WCAG Contrast Ratios (minimum 4.5:1 for normal text, 3:1 for large text)
 * Verify at: https://webaim.org/resources/contrastchecker/
 * - text-light (#f8f9fa) on dark-bg (#0a0e27): 16.9:1 ✓
 * - text-primary (#e9ecef) on dark-bg (#0a0e27): 15.8:1 ✓
 * - text-muted (#a8b2bf) on dark-accent (#1e2749): 5.2:1 ✓
 * - text-muted should NOT be used on cards, use text-primary or lighter
 */
:root {
  --primary-color: #0d6efd;
  --primary-dark: #0b5ed7;
  --dark-bg: #0a0e27;
  --dark-bg-secondary: #1a1f3a;
  --dark-accent: #1e2749;
  --text-light: #f8f9fa;
  --text-primary: #e9ecef;
  --text-muted: #adb5bd;
  --border-color: #495057;
  --gradient-start: #0d6efd;
  --gradient-end: #00d4ff;
  /* Muted text for dark cards - higher contrast than bootstrap default */
  --text-muted-card: #a8b2bf;
}

/* Typography */
html {
  font-size: 14px;
  height: 100%;
}

@media (min-width: 768px) {
  html {
    font-size: 16px;
  }
}

body {
  background: linear-gradient(135deg, #0a0e27 0%, #1a1f3a 100%);
  color: var(--text-primary);
  font-family: -apple-system, BlinkMacSystemFont, "Segoe UI", Roboto, "Helvetica Neue", Arial, sans-serif;
  min-height: 100vh;
  display: flex;
  flex-direction: column;
}

main {
  flex: 1;
}

.container {
  flex: 0 0 auto;
}

.container.flex-grow-1 {
  flex: 1 0 auto;
}

footer {
  flex-shrink: 0;
}

/* Navbar Styling */
.bg-navbar {
  background-color: rgba(10, 14, 39, 0.95) !important;
  backdrop-filter: blur(10px);
}

.navbar-brand {
  color: var(--text-light) !important;
  font-size: 1.5rem;
  letter-spacing: 0.05em;
  font-weight: 700;
}

.navbar-dark .navbar-nav .nav-link {
  color: var(--text-primary) !important;
  transition: color 0.3s ease;
  font-weight: 500;
}

.navbar-dark .navbar-nav .nav-link:hover {
  color: #00d4ff !important;
}

/* Hero Section */
.hero-section {
  background: linear-gradient(135deg, rgba(13, 110, 253, 0.1) 0%, rgba(0, 212, 255, 0.05) 100%);
  border-radius: 20px;
  position: relative;
  overflow: hidden;
}

.hero-section::before {
  content: '';
  position: absolute;
  top: 0;
  left: 0;
  right: 0;
  bottom: 0;
  background: url('data:image/svg+xml,<svg xmlns="http://www.w3.org/2000/svg" viewBox="0 0 100 100"><circle cx="20" cy="20" r="2" fill="rgba(255,255,255,0.03)"/><circle cx="80" cy="80" r="2" fill="rgba(255,255,255,0.03)"/></svg>');
  pointer-events: none;
}

.min-vh-75 {
  min-height: 75vh;
}

.hero-title {
  font-size: 3.5rem;
  font-weight: 800;
  line-height: 1.1;
  margin-bottom: 1.5rem;
  letter-spacing: -0.02em;
  color: var(--text-light);
}

@media (max-width: 768px) {
  .hero-title {
    font-size: 2.5rem;
  }
}

.text-gradient {
  background: linear-gradient(135deg, #00d4ff, #0d6efd);
  -webkit-background-clip: text;
  -webkit-text-fill-color: transparent;
  background-clip: text;
  font-weight: 900;
}

.hero-subtitle {
  font-size: 1.25rem;
  line-height: 1.6;
  color: #d0d8e0 !important;
  font-weight: 500;
}

.text-white-75 {
  color: #b8c5d6 !important;
  font-weight: 500;
}

/* Hero Graphics */
.hero-graphic {
  position: relative;
  height: 400px;
}

.floating-card {
  position: absolute;
  animation: float 6s ease-in-out infinite;
}

.card-1 {
  top: 0;
  right: 0;
  width: 280px;
  animation-delay: 0s;
}

.card-2 {
  bottom: 0;
  left: 50px;
  width: 200px;
  animation-delay: 1s;
}

@keyframes float {
  0%, 100% {
    transform: translateY(0px);
  }
  50% {
    transform: translateY(-20px);
  }
}

/* Buttons */
.btn-primary {
  background-color: var(--primary-color);
  border-color: var(--primary-color);
  font-weight: 600;
  letter-spacing: 0.5px;
  transition: all 0.3s ease;
  color: #ffffff;
}

.btn-primary:hover {
  background-color: var(--primary-dark);
  border-color: var(--primary-dark);
  transform: translateY(-2px);
  box-shadow: 0 10px 25px rgba(13, 110, 253, 0.3);
  color: #ffffff;
}

.btn-outline-light {
  color: var(--text-light);
  border-color: var(--text-light);
  border-width: 2px;
  font-weight: 600;
  letter-spacing: 0.5px;
  transition: all 0.3s ease;
}

.btn-outline-light:hover {
  background-color: var(--text-light);
  border-color: var(--text-light);
  color: var(--dark-bg);
  transform: translateY(-2px);
}

.btn-lg {
  padding: 0.75rem 2rem;
  border-radius: 8px;
  font-size: 1.1rem;
}

/* Prediction Score Display */
.prediction-score {
  display: flex;
  align-items: center;
  justify-content: center;
  gap: 1rem;
  font-size: 2rem;
}

.score-badge {
  background: linear-gradient(135deg, var(--gradient-start), var(--gradient-end));
  padding: 0.5rem 1rem;
  border-radius: 8px;
  font-weight: bold;
  min-width: 50px;
  text-align: center;
  color: #ffffff;
}

.separator {
  color: var(--text-muted);
  font-weight: bold;
}

/* Background Colors */
.bg-dark-accent {
  background-color: var(--dark-accent) !important;
  border: 1px solid rgba(255, 255, 255, 0.1);
  backdrop-filter: blur(10px);
}

/* Features Section */
.features-section {
  padding: 5rem 0;
}

.section-title {
  font-size: 2.5rem;
  font-weight: 800;
  margin-bottom: 1rem;
  color: var(--text-light);
}

.feature-card {
  background-color: var(--dark-accent) !important;
  border: 1px solid rgba(255, 255, 255, 0.1);
  backdrop-filter: blur(10px);
  transition: all 0.3s ease;
  position: relative;
  overflow: hidden;
}

.feature-card::before {
  content: '';
  position: absolute;
  top: 0;
  left: 0;
  right: 0;
  height: 4px;
  background: linear-gradient(90deg, var(--gradient-start), var(--gradient-end));
  opacity: 0;
  transition: opacity 0.3s ease;
}

.feature-card:hover {
  transform: translateY(-10px);
  border-color: rgba(13, 110, 253, 0.5);
  box-shadow: 0 15px 35px rgba(13, 110, 253, 0.2);
}

.feature-card:hover::before {
  opacity: 1;
}

.feature-icon {
  font-size: 2.5rem;
  background: linear-gradient(135deg, #00d4ff, #0d6efd);
  -webkit-background-clip: text;
  -webkit-text-fill-color: transparent;
  background-clip: text;
  margin-bottom: 1rem;
}

.feature-card .card-title {
  color: var(--text-light);
  font-weight: 700;
  font-size: 1.25rem;
}

.feature-card .card-text {
  color: #b8c5d6;
  line-height: 1.6;
  font-weight: 500;
}

  /* CTA Section */
.cta-section {
  padding: 3rem 0;
}

.cta-card {
  background: linear-gradient(135deg, rgba(13, 110, 253, 0.15) 0%, rgba(0, 212, 255, 0.1) 100%);
  border: 1px solid rgba(13, 110, 253, 0.4) !important;
  backdrop-filter: blur(10px);
  border-radius: 16px;
}

.cta-card .card-body h3 {
  font-size: 2rem;
  font-weight: 800;
  margin-bottom: 1rem;
  color: var(--text-light);
}

.cta-card .card-body p {
  color: #b8c5d6;
  font-weight: 500;
}

/* Focus Styles */
.btn:focus, 
.btn:active:focus, 
.btn-link.nav-link:focus, 
.form-control:focus, 
.form-check-input:focus {
  box-shadow: 0 0 0 0.1rem rgba(10, 14, 39, 0.95), 0 0 0 0.25rem rgba(13, 110, 253, 0.5);
}

/* Form Controls */
.form-control,
.form-select {
  background-color: var(--dark-accent);
  border-color: var(--border-color);
  color: var(--text-primary);
  font-weight: 500;
}

.form-control:focus,
.form-select:focus {
  background-color: var(--dark-accent);
  border-color: var(--primary-color);
  color: var(--text-primary);
  box-shadow: 0 0 0 0.25rem rgba(13, 110, 253, 0.25);
}

.form-control::placeholder {
  color: var(--text-muted);
  font-weight: 500;
}

.form-label {
  color: var(--text-primary);
  font-weight: 600;
}

/* Tables — override Bootstrap 5 defaults that break dark theme.
   --bs-table-color defaults to var(--bs-emphasis-color) = black, making text
   invisible on transparent table cells over dark card backgrounds. */
.table {
  --bs-table-color: var(--text-primary);
  --bs-table-bg: transparent;
  --bs-table-hover-color: var(--text-primary);
  --bs-table-hover-bg: rgba(255, 255, 255, 0.05);
  --bs-table-border-color: var(--border-color);
}

/* Cards */
.card {
  background-color: var(--dark-accent);
  border-color: var(--border-color);
  color: var(--text-primary);
}

.card-body {
  color: var(--text-primary);
}

.card-text {
  color: #b8c5d6;
  font-weight: 500;
}

/* Modals */
.modal-content {
  background-color: var(--dark-accent);
  color: var(--text-primary);
  border-color: var(--border-color);
}

.modal-header,
.modal-footer {
  border-color: var(--border-color);
}

/* Footer */
footer {
  margin-top: auto;
  border-color: var(--border-color) !important;
  background-color: rgba(10, 14, 39, 0.5);
}

footer small {
  color: #adb5bd;
  font-weight: 500;
}

footer a {
  color: #adb5bd;
  text-decoration: none;
  transition: color 0.3s ease;
  font-weight: 500;
}

footer a:hover {
  color: #00d4ff;
}

/* Text Utilities - Override for dark cards */
.text-muted {
  color: #8b95a5 !important;
}

.bg-dark-accent .text-muted {
  color: var(--text-muted-card) !important;
}

/* Badges */
.badge {
  font-weight: 600;
  letter-spacing: 0.5px;
}

.badge-success {
  background-color: #28a745 !important;
  color: #ffffff;
}

.badge-danger {
  background-color: #dc3545 !important;
  color: #ffffff;
}

.badge-secondary {
  background-color: #6c757d !important;
  color: #ffffff;
}

/* Alerts */
.alert {
  border-color: var(--border-color);
  background-color: var(--dark-accent);
  color: var(--text-primary);
  font-weight: 500;
}

.alert-light {
  background-color: rgba(233, 236, 239, 0.15) !important;
  border-color: rgba(233, 236, 239, 0.25) !important;
  color: #d0d8e0;
}

.alert-success {
  background-color: rgba(40, 167, 69, 0.15) !important;
  border-color: rgba(40, 167, 69, 0.3) !important;
  color: #86efac;
}

.alert-danger {
  background-color: rgba(220, 53, 69, 0.15) !important;
  border-color: rgba(220, 53, 69, 0.3) !important;
  color: #fca5a5;
}

/* Scrollbar */
::-webkit-scrollbar {
  width: 8px;
}

::-webkit-scrollbar-track {
  background: var(--dark-accent);
}

::-webkit-scrollbar-thumb {
  background: var(--primary-color);
  border-radius: 4px;
}

::-webkit-scrollbar-thumb:hover {
  background: var(--primary-dark);
}

/* Utility Classes */
.form-floating > .form-control-plaintext::placeholder, 
.form-floating > .form-control::placeholder {
  color: var(--text-muted);
  text-align: end;
}

.form-floating > .form-control-plaintext:focus::placeholder, 
.form-floating > .form-control:focus::placeholder {
  text-align: start;
}

/* Animation */
@media (prefers-reduced-motion: no-preference) {
  * {
    scroll-behavior: smooth;
  }
}