/* ===== PROFESSIONAL DARK MODE THEME ===== */
/* Modern, minimal dark mode with CSS variables and WCAG AA compliance */

/* CSS Variables for Light Theme (Default) */
:root {
  /* Background Colors */
  --bg-primary: #ffffff;
  --bg-secondary: #f8f9fa;
  --bg-tertiary: #e9ecef;
  --bg-card: #ffffff;
  --bg-input: #f8f9fa;
  --bg-hover: #f1f3f4;
  
  /* Text Colors */
  --text-primary: #1a1a1a;
  --text-secondary: #4a5568;
  --text-tertiary: #718096;
  --text-muted: #a0aec0;
  --text-inverse: #ffffff;
  
  /* Surface Colors */
  --surface-primary: #ffffff;
  --surface-secondary: #f7fafc;
  --surface-elevated: #ffffff;
  --surface-overlay: rgba(255, 255, 255, 0.95);
  
  /* Accent Colors */
  --accent-primary: #667eea;
  --accent-secondary: #764ba2;
  --accent-hover: #5a6fd8;
  --accent-active: #4c63d2;
  
  /* Border Colors */
  --border-primary: #e2e8f0;
  --border-secondary: #cbd5e0;
  --border-focus: #667eea;
  --border-subtle: rgba(226, 232, 240, 0.5);
  
  /* Status Colors */
  --success: #48bb78;
  --success-bg: #f0fff4;
  --success-border: #c6f6d5;
  --error: #f56565;
  --error-bg: #fff5f5;
  --error-border: #fed7d7;
  --warning: #ed8936;
  --warning-bg: #fffaf0;
  --warning-border: #feebc8;
  --info: #4299e1;
  --info-bg: #ebf8ff;
  --info-border: #bee3f8;
  
  /* Shadow Colors */
  --shadow-sm: 0 1px 3px rgba(0, 0, 0, 0.1);
  --shadow-md: 0 4px 12px rgba(0, 0, 0, 0.1);
  --shadow-lg: 0 8px 32px rgba(0, 0, 0, 0.12);
  --shadow-xl: 0 16px 64px rgba(0, 0, 0, 0.15);
  
  /* Gradient Colors */
  --gradient-primary: linear-gradient(135deg, #667eea, #764ba2);
  --gradient-secondary: linear-gradient(135deg, #f8f9fa, #e9ecef);
  
  /* Spacing */
  --space-xs: 0.25rem;
  --space-sm: 0.5rem;
  --space-md: 1rem;
  --space-lg: 1.5rem;
  --space-xl: 2rem;
  --space-2xl: 3rem;
  
  /* Border Radius */
  --radius-sm: 0.25rem;
  --radius-md: 0.5rem;
  --radius-lg: 0.75rem;
  --radius-xl: 1rem;
  --radius-2xl: 1.5rem;
  
  /* Transitions */
  --transition-fast: 0.15s ease;
  --transition-normal: 0.3s ease;
  --transition-slow: 0.5s ease;
}

/* CSS Variables for Dark Theme */
[data-theme="dark"] {
  /* Background Colors */
  --bg-primary: #0f1419;
  --bg-secondary: #1a1f2e;
  --bg-tertiary: #242938;
  --bg-card: #161b22;
  --bg-input: #21262d;
  --bg-hover: #30363d;
  
  /* Text Colors */
  --text-primary: #f0f6fc;
  --text-secondary: #c9d1d9;
  --text-tertiary: #8b949e;
  --text-muted: #6e7681;
  --text-inverse: #0f1419;
  
  /* Surface Colors */
  --surface-primary: #161b22;
  --surface-secondary: #21262d;
  --surface-elevated: #1c2128;
  --surface-overlay: rgba(22, 27, 34, 0.95);
  
  /* Accent Colors */
  --accent-primary: #7c8cff;
  --accent-secondary: #8b5cf6;
  --accent-hover: #6b7ae8;
  --accent-active: #5a6fd8;
  
  /* Border Colors */
  --border-primary: #30363d;
  --border-secondary: #21262d;
  --border-focus: #7c8cff;
  --border-subtle: rgba(48, 54, 61, 0.5);
  
  /* Status Colors */
  --success: #56d364;
  --success-bg: #0d1117;
  --success-border: #238636;
  --error: #f85149;
  --error-bg: #0d1117;
  --error-border: #da3633;
  --warning: #e3b341;
  --warning-bg: #0d1117;
  --warning-border: #d29922;
  --info: #58a6ff;
  --info-bg: #0d1117;
  --info-border: #1f6feb;
  
  /* Shadow Colors */
  --shadow-sm: 0 1px 3px rgba(0, 0, 0, 0.3);
  --shadow-md: 0 4px 12px rgba(0, 0, 0, 0.4);
  --shadow-lg: 0 8px 32px rgba(0, 0, 0, 0.5);
  --shadow-xl: 0 16px 64px rgba(0, 0, 0, 0.6);
  
  /* Gradient Colors */
  --gradient-primary: linear-gradient(135deg, #7c8cff, #8b5cf6);
  --gradient-secondary: linear-gradient(135deg, #1a1f2e, #242938);
}

/* ===== COMPATIBILITY WITH EXISTING STYLES ===== */
/* Ensure dark mode works with existing body.dark styles */
body.dark {
  background: var(--bg-primary) !important;
  color: var(--text-primary) !important;
}

/* ===== BASE STYLES ===== */
* {
  margin: 0;
  padding: 0;
  box-sizing: border-box;
}

body {
  font-family: -apple-system, BlinkMacSystemFont, 'Segoe UI', Roboto, 'Helvetica Neue', Arial, sans-serif;
  background: var(--bg-primary);
  color: var(--text-primary);
  line-height: 1.6;
  min-height: 100vh;
  transition: background-color var(--transition-normal), color var(--transition-normal);
}

/* ===== TYPOGRAPHY ===== */
h1, h2, h3, h4, h5, h6 {
  color: var(--text-primary);
  font-weight: 600;
  margin-bottom: var(--space-md);
  line-height: 1.25;
}

h1 {
  font-size: 2.5rem;
  font-weight: 700;
  background: var(--gradient-primary);
  -webkit-background-clip: text;
  -webkit-text-fill-color: transparent;
  background-clip: text;
}

h2 {
  font-size: 2rem;
  font-weight: 600;
}

h3 {
  font-size: 1.5rem;
  font-weight: 600;
}

h4 {
  font-size: 1.25rem;
  font-weight: 600;
}

p {
  color: var(--text-secondary);
  font-size: 1rem;
  line-height: 1.6;
  margin-bottom: var(--space-md);
}

/* ===== NAVIGATION ===== */
.navbar {
  background: var(--surface-overlay);
  backdrop-filter: blur(20px);
  border-bottom: 1px solid var(--border-primary);
  position: sticky;
  top: 0;
  z-index: 1000;
  box-shadow: var(--shadow-sm);
  transition: all var(--transition-normal);
}

.nav-container {
  max-width: 1200px;
  margin: 0 auto;
  padding: 0 var(--space-lg);
  display: flex;
  justify-content: space-between;
  align-items: center;
  height: 80px;
}

.nav-brand h2 {
  background: var(--gradient-primary);
  -webkit-background-clip: text;
  -webkit-text-fill-color: transparent;
  background-clip: text;
  font-size: 1.8rem;
  font-weight: 700;
}

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

.nav-link {
  text-decoration: none;
  color: var(--text-secondary);
  font-weight: 500;
  padding: var(--space-sm) var(--space-md);
  border-radius: var(--radius-lg);
  transition: all var(--transition-normal);
  position: relative;
}

.nav-link:hover,
.nav-link.active {
  background: var(--gradient-primary);
  color: var(--text-inverse);
  transform: translateY(-1px);
  box-shadow: var(--shadow-md);
}

/* ===== BUTTONS ===== */
.btn {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  gap: var(--space-sm);
  padding: var(--space-md) var(--space-xl);
  border: none;
  border-radius: var(--radius-lg);
  font-size: 1rem;
  font-weight: 600;
  cursor: pointer;
  text-decoration: none;
  transition: all var(--transition-normal);
  box-shadow: var(--shadow-sm);
  outline: none;
  position: relative;
}

.btn:focus-visible {
  outline: 2px solid var(--border-focus);
  outline-offset: 2px;
}

.btn-primary {
  background: var(--gradient-primary);
  color: var(--text-inverse);
}

.btn-primary:hover {
  transform: translateY(-2px);
  box-shadow: var(--shadow-lg);
  filter: brightness(1.1);
}

.btn-primary:active {
  transform: translateY(0);
}

.btn-secondary {
  background: var(--surface-secondary);
  color: var(--text-primary);
  border: 2px solid var(--border-primary);
}

.btn-secondary:hover {
  background: var(--bg-hover);
  border-color: var(--border-focus);
  transform: translateY(-2px);
}

.btn-outline {
  background: transparent;
  color: var(--accent-primary);
  border: 2px solid var(--accent-primary);
}

.btn-outline:hover {
  background: var(--accent-primary);
  color: var(--text-inverse);
  transform: translateY(-2px);
}

/* ===== FORMS ===== */
.form-group {
  margin-bottom: var(--space-lg);
}

label {
  display: block;
  margin-bottom: var(--space-sm);
  font-weight: 600;
  color: var(--text-primary);
  font-size: 1rem;
}

input[type="email"],
input[type="password"],
input[type="text"],
textarea {
  width: 100%;
  padding: var(--space-md);
  border: 2px solid var(--border-primary);
  border-radius: var(--radius-lg);
  font-size: 1rem;
  font-family: inherit;
  background: var(--bg-input);
  transition: all var(--transition-normal);
  color: var(--text-primary);
}

input[type="email"]:focus,
input[type="password"]:focus,
input[type="text"]:focus,
textarea:focus {
  border-color: var(--border-focus);
  outline: none;
  background: var(--surface-primary);
  box-shadow: 0 0 0 3px rgba(124, 140, 255, 0.1);
}

textarea {
  min-height: 140px;
  resize: vertical;
  line-height: 1.6;
}

/* ===== CARDS ===== */
.card,
.container,
.auth-container,
.faq-container,
.analysis-card,
.feature-card,
.result-card,
.pricing-card,
.payment-section {
  background: var(--bg-card);
  border: 1px solid var(--border-primary);
  border-radius: var(--radius-xl);
  padding: var(--space-xl);
  margin-bottom: var(--space-lg);
  box-shadow: var(--shadow-md);
  transition: all var(--transition-normal);
}

.card:hover,
.analysis-card:hover,
.feature-card:hover {
  transform: translateY(-2px);
  box-shadow: var(--shadow-lg);
  border-color: var(--border-focus);
}

/* ===== MODALS ===== */
.modal {
  position: fixed;
  top: 0;
  left: 0;
  width: 100%;
  height: 100%;
  background: rgba(0, 0, 0, 0.5);
  display: flex;
  align-items: center;
  justify-content: center;
  z-index: 10000;
  opacity: 0;
  visibility: hidden;
  transition: all var(--transition-normal);
}

.modal.active {
  opacity: 1;
  visibility: visible;
}

.modal-content {
  background: var(--bg-card);
  border-radius: var(--radius-xl);
  padding: var(--space-2xl);
  max-width: 500px;
  width: 90%;
  max-height: 80vh;
  overflow-y: auto;
  box-shadow: var(--shadow-xl);
  border: 1px solid var(--border-primary);
  transform: scale(0.9);
  transition: transform var(--transition-normal);
}

.modal.active .modal-content {
  transform: scale(1);
}

/* ===== TABLES ===== */
table {
  width: 100%;
  border-collapse: collapse;
  background: var(--bg-card);
  border-radius: var(--radius-lg);
  overflow: hidden;
  box-shadow: var(--shadow-sm);
  border: 1px solid var(--border-primary);
}

th,
td {
  padding: var(--space-md);
  text-align: left;
  border-bottom: 1px solid var(--border-primary);
}

th {
  background: var(--surface-secondary);
  color: var(--text-primary);
  font-weight: 600;
}

tr:hover {
  background: var(--bg-hover);
}

/* ===== STATUS MESSAGES ===== */
.flash-message,
.alert {
  padding: var(--space-md);
  border-radius: var(--radius-lg);
  margin-bottom: var(--space-md);
  font-weight: 500;
  border-left: 4px solid;
  transition: all var(--transition-normal);
}

.flash-success,
.alert-success {
  background: var(--success-bg);
  color: var(--success);
  border-left-color: var(--success);
}

.flash-error,
.alert-error {
  background: var(--error-bg);
  color: var(--error);
  border-left-color: var(--error);
}

.flash-warning,
.alert-warning {
  background: var(--warning-bg);
  color: var(--warning);
  border-left-color: var(--warning);
}

.flash-info,
.alert-info {
  background: var(--info-bg);
  color: var(--info);
  border-left-color: var(--info);
}

/* ===== THEME TOGGLE ===== */
.theme-toggle {
  background: var(--surface-secondary);
  border: 2px solid var(--border-primary);
  border-radius: var(--radius-lg);
  padding: var(--space-sm);
  cursor: pointer;
  transition: all var(--transition-normal);
  font-size: 1.2rem;
  width: 44px;
  height: 44px;
  display: flex;
  align-items: center;
  justify-content: center;
}

.theme-toggle:hover {
  background: var(--bg-hover);
  border-color: var(--border-focus);
  transform: scale(1.05);
}

.theme-toggle:focus-visible {
  outline: 2px solid var(--border-focus);
  outline-offset: 2px;
}

/* Theme toggle as menu item */
.theme-toggle-menu {
  display: flex !important;
  align-items: center !important;
  gap: var(--space-sm) !important;
  padding: var(--space-md) var(--space-lg) !important;
  border-radius: var(--radius-lg) !important;
  transition: all var(--transition-normal) !important;
  font-weight: 500 !important;
  text-decoration: none !important;
  border: 1px solid transparent !important;
  margin: var(--space-xs) 0 !important;
}

.theme-toggle-menu:hover {
  background: var(--bg-hover) !important;
  border-color: var(--border-focus) !important;
  transform: translateY(-1px) !important;
  box-shadow: var(--shadow-sm) !important;
}

.theme-toggle-menu:focus-visible {
  outline: 2px solid var(--border-focus) !important;
  outline-offset: 2px !important;
}

.theme-toggle-menu:active {
  transform: translateY(0) !important;
}

/* ===== FOOTER ===== */
.footer {
  background: var(--surface-secondary);
  border-top: 1px solid var(--border-primary);
  padding: var(--space-2xl) 0;
  margin-top: var(--space-2xl);
  text-align: center;
}

.footer-content {
  max-width: 1200px;
  margin: 0 auto;
  padding: 0 var(--space-lg);
}

.footer-links a {
  color: var(--accent-primary);
  text-decoration: none;
  margin: 0 var(--space-md);
  transition: color var(--transition-normal);
}

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

/* ===== RESPONSIVE DESIGN ===== */
@media (max-width: 768px) {
  .nav-container {
    padding: 0 var(--space-md);
  }
  
  .nav-links {
    position: fixed;
    top: 80px;
    left: -100%;
    width: 100%;
    height: calc(100vh - 80px);
    background: var(--surface-overlay);
    backdrop-filter: blur(20px);
    flex-direction: column;
    justify-content: flex-start;
    align-items: center;
    padding-top: var(--space-2xl);
    transition: left var(--transition-normal);
    box-shadow: var(--shadow-lg);
    border-top: 1px solid var(--border-primary);
  }

  .nav-links.active {
    left: 0;
  }

  /* Theme toggle in mobile menu */
  .theme-toggle-menu {
    width: 90% !important;
    max-width: 300px !important;
    justify-content: center !important;
    margin: var(--space-md) 0 !important;
    padding: var(--space-lg) var(--space-xl) !important;
    font-size: 1.1rem !important;
    border: 2px solid var(--border-primary) !important;
    background: var(--surface-secondary) !important;
  }

  .theme-toggle-menu:hover {
    background: var(--bg-hover) !important;
    border-color: var(--border-focus) !important;
  }

  .container,
  .auth-container,
  .faq-container {
    margin: var(--space-lg) var(--space-md);
    padding: var(--space-lg);
  }

  h1 {
    font-size: 2rem;
  }

  .btn {
    padding: var(--space-md) var(--space-lg);
    font-size: 0.95rem;
  }
}

@media (max-width: 480px) {
  .nav-container {
    padding: 0 var(--space-md);
  }

  .container,
  .auth-container,
  .faq-container {
    margin: var(--space-md);
    padding: var(--space-md);
  }

  h1 {
    font-size: 1.75rem;
  }

  .btn {
    width: 100%;
    padding: var(--space-md);
  }
}

/* ===== ACCESSIBILITY ===== */
@media (prefers-reduced-motion: reduce) {
  * {
    animation-duration: 0.01ms !important;
    animation-iteration-count: 1 !important;
    transition-duration: 0.01ms !important;
  }
}

/* High contrast mode support */
@media (prefers-contrast: high) {
  :root {
    --border-primary: #000000;
    --text-primary: #000000;
  }
  
  [data-theme="dark"] {
    --border-primary: #ffffff;
    --text-primary: #ffffff;
  }
}

/* Focus styles for keyboard navigation */
*:focus-visible {
  outline: 2px solid var(--border-focus);
  outline-offset: 2px;
}

/* Skip link for screen readers */
.skip-link {
  position: absolute;
  top: -40px;
  left: 6px;
  background: var(--accent-primary);
  color: var(--text-inverse);
  padding: var(--space-sm) var(--space-md);
  text-decoration: none;
  border-radius: var(--radius-md);
  z-index: 10001;
}

.skip-link:focus {
  top: 6px;
}