/* Glassmorphism Design System for Renxuai.com */
:root {
  /* Primary brand colors */
  --primary-500: #2563eb;
  --primary-600: #1d4ed8;
  --primary-700: #1e40af;
  --cta-500: #f97316;
  --cta-600: #ea580c;
  
  /* Glassmorphism base colors */
  --glass-bg: rgba(255, 255, 255, 0.8);
  --glass-bg-dark: rgba(255, 255, 255, 0.1);
  --glass-border: rgba(255, 255, 255, 0.2);
  --glass-border-dark: rgba(255, 255, 255, 0.1);
  
  /* Text colors */
  --text-primary: #1e293b;
  --text-secondary: #475569;
  --text-muted: #64748b;
  --text-on-primary: #ffffff;
  
  /* Background colors */
  --bg-base: #f8fafc;
  --bg-surface: #ffffff;
  
  /* Dark mode variants */
  --dark-bg-base: #0f172a;
  --dark-bg-surface: #1e293b;
  --dark-text-primary: #f1f5f9;
  --dark-text-secondary: #cbd5e1;
  --dark-text-muted: #94a3b8;
  
  /* Shadows */
  --shadow-sm: 0 1px 2px 0 rgba(0, 0, 0, 0.05);
  --shadow-md: 0 4px 6px -1px rgba(0, 0, 0, 0.1), 0 2px 4px -2px rgba(0, 0, 0, 0.1);
  --shadow-lg: 0 10px 15px -3px rgba(0, 0, 0, 0.1), 0 4px 6px -4px rgba(0, 0, 0, 0.1);
  
  /* Border radius */
  --radius-sm: 0.25rem;
  --radius-md: 0.5rem;
  --radius-lg: 0.75rem;
  --radius-xl: 1rem;
  --radius-2xl: 1.5rem;
  --radius-full: 9999px;
  
  /* Spacing */
  --spacing-xs: 0.25rem;
  --spacing-sm: 0.5rem;
  --spacing-md: 1rem;
  --spacing-lg: 1.5rem;
  --spacing-xl: 2rem;
  --spacing-2xl: 3rem;
  
  /* Fonts */
  --font-sans: "Poppins", "Open Sans", "Inter", ui-sans-serif, system-ui, sans-serif;
  --font-mono: ui-monospace, SFMono-Regular, Menlo, Monaco, Consolas, "Liberation Mono", "Courier New", monospace;
}

/* Dark mode variables */
[data-theme="dark"] {
  --glass-bg: rgba(30, 41, 59, 0.8);
  --glass-bg-dark: rgba(15, 23, 42, 0.8);
  --glass-border: rgba(255, 255, 255, 0.1);
  --glass-border-dark: rgba(255, 255, 255, 0.05);
  --text-primary: var(--dark-text-primary);
  --text-secondary: var(--dark-text-secondary);
  --text-muted: var(--dark-text-muted);
  --bg-base: var(--dark-bg-base);
  --bg-surface: var(--dark-bg-surface);
}

* {
  box-sizing: border-box;
}

html {
  scroll-behavior: smooth;
}

body {
  margin: 0;
  font-family: var(--font-sans);
  background: linear-gradient(135deg, var(--bg-base) 0%, #e2e8f0 100%);
  color: var(--text-primary);
  line-height: 1.6;
}

/* Container */
.container {
  width: min(1200px, 92vw);
  margin: 0 auto;
}

/* Skip link for accessibility */
.skip-link {
  position: absolute;
  left: -9999px;
}

.skip-link:focus {
  left: 12px;
  top: 10px;
  background: var(--primary-500);
  color: var(--text-on-primary);
  padding: 6px 10px;
  border-radius: var(--radius-md);
  z-index: 1000;
}

/* Navigation */
.top-nav {
  position: sticky;
  top: 0;
  z-index: 100;
  backdrop-filter: blur(12px);
  -webkit-backdrop-filter: blur(12px);
  background: var(--glass-bg);
  border-bottom: 1px solid var(--glass-border);
}

.nav-container {
  display: flex;
  align-items: center;
  justify-content: space-between;
  padding: 16px 0;
  gap: 12px;
  width: min(1200px, 92vw);
  margin: 0 auto;
}

.nav-logo {
  display: flex;
  align-items: center;
  gap: 10px;
  font-size: 20px;
  font-weight: 700;
  letter-spacing: 0.02em;
  color: var(--text-primary);
  text-decoration: none;
}

.nav-links {
  display: flex;
  gap: 20px;
  font-size: 14px;
  font-weight: 500;
}

.nav-links a {
  color: var(--text-secondary);
  text-decoration: none;
  transition: color 0.2s ease;
}

.nav-links a:hover {
  color: var(--primary-500);
}

.nav-dropdown {
  position: relative;
}

.nav-dropdown > span {
  color: var(--text-secondary);
  cursor: pointer;
  transition: color 0.2s ease;
}

.nav-dropdown:hover > span,
.nav-dropdown:focus > span {
  color: var(--primary-500);
}

.dropdown-content {
  position: absolute;
  top: 100%;
  left: 0;
  background: var(--glass-bg);
  backdrop-filter: blur(12px);
  -webkit-backdrop-filter: blur(12px);
  border: 1px solid var(--glass-border);
  border-radius: var(--radius-lg);
  box-shadow: var(--shadow-md);
  min-width: 200px;
  z-index: 1000;
  opacity: 0;
  visibility: hidden;
  transform: translateY(-10px);
  transition: color 0.2s ease, background-color 0.2s ease, border-color 0.2s ease, transform 0.2s ease, opacity 0.2s ease;
  padding: 8px 0;
}

.nav-dropdown:hover .dropdown-content,
.nav-dropdown:focus .dropdown-content {
  opacity: 1;
  visibility: visible;
  transform: translateY(0);
}

.dropdown-content a {
  display: block;
  padding: 8px 16px;
  color: var(--text-secondary);
  text-decoration: none;
  transition: color 0.2s ease, background-color 0.2s ease, border-color 0.2s ease, transform 0.2s ease, opacity 0.2s ease;
}

.dropdown-content a:hover {
  background: var(--primary-500);
  color: var(--text-on-primary);
}

/* Header */
.scenario-header {
  padding: 64px 0 40px;
  text-align: center;
  background: linear-gradient(135deg, var(--bg-base) 0%, #e2e8f0 100%);
}

.scenario-header h1 {
  margin: 0;
  font-size: clamp(32px, 4vw, 56px);
  font-weight: 700;
  line-height: 1.1;
  letter-spacing: -0.02em;
  color: var(--text-primary);
}

.scenario-meta {
  margin-top: 16px;
  font-size: 18px;
  color: var(--text-secondary);
}

.scenario-meta span {
  margin: 0 12px;
}

/* Main Content */
.scenario-content {
  padding: 40px 0 60px;
}

.scenario-section {
  margin-bottom: 40px;
}

.scenario-section h2 {
  margin: 0 0 24px;
  font-size: 28px;
  font-weight: 700;
  color: var(--text-primary);
}

.scenario-section h3 {
  margin: 24px 0 16px;
  font-size: 22px;
  font-weight: 600;
  color: var(--text-primary);
}

/* Story Box */
.story-box {
  background: var(--glass-bg);
  backdrop-filter: blur(12px);
  -webkit-backdrop-filter: blur(12px);
  border: 1px solid var(--glass-border);
  border-radius: var(--radius-xl);
  padding: 24px;
  box-shadow: var(--shadow-md);
  margin-bottom: 24px;
}

.story-box p {
  margin: 12px 0;
  line-height: 1.7;
}

.story-box strong {
  color: var(--primary-500);
}

/* Problem and Solution Boxes */
.problem-box,
.solution-box {
  background: var(--glass-bg);
  backdrop-filter: blur(12px);
  -webkit-backdrop-filter: blur(12px);
  border: 1px solid var(--glass-border);
  border-radius: var(--radius-xl);
  padding: 24px;
  box-shadow: var(--shadow-md);
  margin-bottom: 24px;
}

.problem-box {
  border-left: 4px solid #ef4444;
}

.solution-box {
  border-left: 4px solid var(--primary-500);
}

/* Stats Grid */
.stats-grid {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(200px, 1fr));
  gap: 24px;
  margin: 32px 0;
}

.stat-item {
  text-align: center;
  background: var(--glass-bg);
  backdrop-filter: blur(12px);
  -webkit-backdrop-filter: blur(12px);
  border: 1px solid var(--glass-border);
  border-radius: var(--radius-xl);
  padding: 24px;
  box-shadow: var(--shadow-md);
}

.stat-value {
  font-size: 36px;
  font-weight: 700;
  color: var(--primary-500);
  margin-bottom: 8px;
}

.stat-label {
  font-size: 14px;
  font-weight: 600;
  color: var(--text-muted);
  text-transform: uppercase;
  letter-spacing: 0.08em;
}

/* Lists */
ul {
  padding-left: 24px;
  margin: 16px 0;
}

li {
  margin: 8px 0;
  line-height: 1.7;
  color: var(--text-secondary);
}

/* CTA Section */
.cta-section {
  background: linear-gradient(135deg, var(--primary-500) 0%, var(--primary-600) 100%);
  color: var(--text-on-primary);
  padding: 64px 0;
  text-align: center;
  border-radius: var(--radius-2xl);
  margin: 40px 0;
}

.cta-section .container {
  max-width: 800px;
}

.cta-section h2 {
  margin: 0 0 16px;
  font-size: 36px;
  font-weight: 700;
  color: var(--text-on-primary);
}

.cta-section p {
  margin: 0 0 32px;
  font-size: 18px;
  line-height: 1.7;
  color: rgba(255, 255, 255, 0.9);
}

.cta-button {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  padding: 12px 32px;
  background: var(--text-on-primary);
  color: var(--primary-500);
  border-radius: var(--radius-full);
  font-size: 16px;
  font-weight: 600;
  text-decoration: none;
  transition: color 0.2s ease, background-color 0.2s ease, border-color 0.2s ease, transform 0.2s ease, opacity 0.2s ease;
  box-shadow: var(--shadow-lg);
}

.cta-button:hover {
  transform: translateY(-2px);
  box-shadow: 0 12px 20px -4px rgba(0, 0, 0, 0.2);
}

/* Footer */
.footer {
  background: var(--glass-bg);
  backdrop-filter: blur(12px);
  -webkit-backdrop-filter: blur(12px);
  border-top: 1px solid var(--glass-border);
  padding: 48px 0 32px;
  margin-top: 60px;
}

.footer-content {
  display: flex;
  justify-content: space-between;
  gap: 40px;
  margin-bottom: 32px;
}

.footer-info h3 {
  margin: 0 0 12px;
  font-size: 20px;
  font-weight: 700;
  color: var(--text-primary);
}

.footer-info p {
  margin: 0;
  color: var(--text-secondary);
}

.footer-links {
  display: flex;
  gap: 24px;
}

.footer-links a {
  color: var(--text-secondary);
  font-weight: 500;
  text-decoration: none;
  transition: color 0.2s ease;
}

.footer-links a:hover {
  color: var(--primary-500);
}

.footer-copyright {
  text-align: center;
  padding-top: 32px;
  border-top: 1px solid var(--glass-border);
  color: var(--text-muted);
}

/* Responsive design */
@media (max-width: 960px) {
  .nav-container {
    flex-direction: column;
    align-items: flex-start;
  }
  
  .nav-links {
    margin-top: 16px;
    flex-wrap: wrap;
  }
  
  .scenario-header {
    padding: 40px 0 24px;
  }
  
  .scenario-header h1 {
    font-size: clamp(28px, 6vw, 42px);
  }
  
  .stats-grid {
    grid-template-columns: repeat(2, 1fr);
  }
  
  .footer-content {
    flex-direction: column;
    gap: 24px;
  }
}

@media (max-width: 640px) {
  .scenario-content {
    padding: 28px 0 40px;
  }
  
  .scenario-section {
    margin-bottom: 28px;
  }
  
  .stats-grid {
    grid-template-columns: 1fr;
  }
  
  .story-box,
  .problem-box,
  .solution-box,
  .stat-item {
    padding: 20px;
    border-radius: var(--radius-lg);
  }
  
  .cta-section {
    padding: 40px 0;
    border-radius: var(--radius-xl);
  }
  
  .cta-section h2 {
    font-size: 28px;
  }
  
  .cta-button {
    width: 100%;
    max-width: 300px;
  }
}

/* Accessibility enhancements */
:focus-visible {
  outline: 2px solid var(--primary-500);
  outline-offset: 2px;
}

/* Ensure sufficient contrast for WCAG AA compliance */
a:not(.cta-button):not(.nav-logo):not(.nav-links a) {
  color: var(--primary-500);
  text-decoration: underline;
  text-underline-offset: 2px;
}

a:not(.cta-button):not(.nav-logo):not(.nav-links a):hover {
  color: var(--primary-600);
}

hr {
  border: 0;
  height: 1px;
  background: var(--glass-border);
  margin: 32px 0;
}


@media (prefers-reduced-motion: reduce) {
  *, *::before, *::after {
    animation-duration: 0.01ms !important;
    animation-iteration-count: 1 !important;
    transition-duration: 0.01ms !important;
    scroll-behavior: auto !important;
  }
}