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

/* ===== CSS VARIABLES ===== */
:root {
  /* Light Theme Colors */
  --color-primary: #8B4513;
  --color-primary-dark: #6B3410;
  --color-primary-light: #A0522D;
  --color-accent: #14B8A6;
  --color-accent-dark: #0D9488;
  --color-accent-light: #2DD4BF;
  
  --color-bg-primary: #FFFFFF;
  --color-bg-secondary: #F8F7F4;
  --color-bg-tertiary: #F0EDE8;
  --color-surface: #FFFFFF;
  --color-surface-elevated: #FFFFFF;
  
  --color-text-primary: #1F2937;
  --color-text-secondary: #6B7280;
  --color-text-tertiary: #9CA3AF;
  --color-text-inverse: #FFFFFF;
  
  --color-border: #E5E7EB;
  --color-border-light: #F3F4F6;
  
  --color-success: #10B981;
  --color-error: #EF4444;
  --color-warning: #F59E0B;
  
  /* 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 -1px rgba(0, 0, 0, 0.06);
  --shadow-lg: 0 10px 15px -3px rgba(0, 0, 0, 0.1), 0 4px 6px -2px rgba(0, 0, 0, 0.05);
  --shadow-xl: 0 20px 25px -5px rgba(0, 0, 0, 0.1), 0 10px 10px -5px rgba(0, 0, 0, 0.04);
  --shadow-2xl: 0 25px 50px -12px rgba(0, 0, 0, 0.25);
  
  /* Spacing */
  --spacing-xs: 0.25rem;
  --spacing-sm: 0.5rem;
  --spacing-md: 1rem;
  --spacing-lg: 1.5rem;
  --spacing-xl: 2rem;
  --spacing-2xl: 3rem;
  --spacing-3xl: 4rem;
  
  /* Border Radius */
  --radius-sm: 0.375rem;
  --radius-md: 0.5rem;
  --radius-lg: 0.75rem;
  --radius-xl: 1rem;
  --radius-2xl: 1.5rem;
  --radius-full: 9999px;
  
  /* Typography */
  --font-family: 'Inter', -apple-system, BlinkMacSystemFont, 'Segoe UI', sans-serif;
  --font-size-xs: 0.75rem;
  --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: 1.875rem;
  --font-size-4xl: 2.25rem;
  --font-size-5xl: 3rem;
  
  /* Transitions */
  --transition-fast: 150ms cubic-bezier(0.4, 0, 0.2, 1);
  --transition-base: 250ms cubic-bezier(0.4, 0, 0.2, 1);
  --transition-slow: 350ms cubic-bezier(0.4, 0, 0.2, 1);
  
  /* Z-index */
  --z-dropdown: 1000;
  --z-sticky: 1020;
  --z-fixed: 1030;
  --z-modal-backdrop: 1040;
  --z-modal: 1050;
  --z-popover: 1060;
  --z-tooltip: 1070;
}

/* Dark Theme */
[data-theme="dark"] {
  --color-bg-primary: #111827;
  --color-bg-secondary: #1F2937;
  --color-bg-tertiary: #374151;
  --color-surface: #1F2937;
  --color-surface-elevated: #374151;
  
  --color-text-primary: #F9FAFB;
  --color-text-secondary: #D1D5DB;
  --color-text-tertiary: #9CA3AF;
  
  --color-border: #374151;
  --color-border-light: #4B5563;
  
  --shadow-sm: 0 1px 2px 0 rgba(0, 0, 0, 0.3);
  --shadow-md: 0 4px 6px -1px rgba(0, 0, 0, 0.4), 0 2px 4px -1px rgba(0, 0, 0, 0.3);
  --shadow-lg: 0 10px 15px -3px rgba(0, 0, 0, 0.4), 0 4px 6px -2px rgba(0, 0, 0, 0.3);
  --shadow-xl: 0 20px 25px -5px rgba(0, 0, 0, 0.4), 0 10px 10px -5px rgba(0, 0, 0, 0.3);
  --shadow-2xl: 0 25px 50px -12px rgba(0, 0, 0, 0.5);
}

/* ===== RESET & BASE STYLES ===== */
*, *::before, *::after {
  box-sizing: border-box;
  margin: 0;
  padding: 0;
}

html {
  scroll-behavior: smooth;
  font-size: 16px;
  /* Prevent font size inflation on mobile landscape */
  -webkit-text-size-adjust: 100%;
  text-size-adjust: 100%;
}

body {
  font-family: var(--font-family);
  font-size: var(--font-size-base);
  line-height: 1.6;
  color: var(--color-text-primary);
  background-color: var(--color-bg-primary);
  transition: background-color var(--transition-base), color var(--transition-base);
  overflow-x: hidden;
  /* Smooth scrolling momentum on iOS */
  -webkit-overflow-scrolling: touch;
}

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

a {
  text-decoration: none;
  color: inherit;
  transition: color var(--transition-fast);
}

button {
  font-family: inherit;
  cursor: pointer;
  border: none;
  background: none;
  transition: all var(--transition-fast);
  /* Prevent double-tap zoom on mobile */
  touch-action: manipulation;
}

input, textarea, select {
  font-family: inherit;
  font-size: inherit;
  /* Prevent iOS zoom on focus — minimum 16px */
  font-size: max(16px, 1rem);
}

/* ===== UTILITY CLASSES ===== */
.container {
  width: 100%;
  max-width: 1280px;
  margin: 0 auto;
  padding: 0 var(--spacing-lg);
}

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

.section-title {
  font-size: var(--font-size-4xl);
  font-weight: 800;
  text-align: center;
  margin-bottom: var(--spacing-md);
  color: var(--color-text-primary);
  letter-spacing: -0.02em;
  /* Prevent long words from breaking layout on small screens */
  overflow-wrap: break-word;
  word-break: break-word;
}

.section-subtitle {
  font-size: var(--font-size-lg);
  text-align: center;
  color: var(--color-text-secondary);
  margin-bottom: var(--spacing-2xl);
  max-width: 600px;
  margin-left: auto;
  margin-right: auto;
  overflow-wrap: break-word;
}

.btn {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  gap: var(--spacing-sm);
  padding: var(--spacing-md) var(--spacing-xl);
  font-size: var(--font-size-base);
  font-weight: 600;
  border-radius: var(--radius-lg);
  transition: all var(--transition-base);
  cursor: pointer;
  border: none;
  text-decoration: none;
  /* Touch-friendly minimum target */
  min-height: 44px;
  /* Prevent double-tap zoom */
  touch-action: manipulation;
}

.btn-primary {
  background: linear-gradient(135deg, var(--color-primary) 0%, var(--color-primary-light) 100%);
  color: var(--color-text-inverse);
  box-shadow: var(--shadow-md);
}

.btn-primary:hover {
  transform: translateY(-2px);
  box-shadow: var(--shadow-lg);
  background: linear-gradient(135deg, var(--color-primary-dark) 0%, var(--color-primary) 100%);
}

.btn-accent {
  background: linear-gradient(135deg, var(--color-accent-dark) 0%, var(--color-accent-dark) 100%);
  color: var(--color-text-inverse);
  box-shadow: var(--shadow-md);
}

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

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

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

/* Full-width button helper for mobile */
.btn-block {
  width: 100%;
  justify-content: center;
}

.grid {
  display: grid;
  gap: var(--spacing-lg);
}

.grid-2 {
  grid-template-columns: repeat(auto-fit, minmax(300px, 1fr));
}

.grid-3 {
  grid-template-columns: repeat(auto-fit, minmax(280px, 1fr));
}

.grid-4 {
  grid-template-columns: repeat(auto-fit, minmax(250px, 1fr));
}

.fade-in {
  opacity: 0;
  transform: translateY(20px);
  transition: opacity var(--transition-slow), transform var(--transition-slow);
}

.fade-in.visible {
  opacity: 1;
  transform: translateY(0);
}

/* ===== NAVIGATION ===== */
.navbar {
  position: sticky;
  top: 0;
  z-index: var(--z-sticky);
  background: var(--color-surface);
  backdrop-filter: blur(10px);
  -webkit-backdrop-filter: blur(10px); /* Safari support */
  border-bottom: 1px solid var(--color-border);
  transition: all var(--transition-base);
}

.navbar.scrolled {
  box-shadow: var(--shadow-md);
}

.navbar .container {
  display: flex;
  align-items: center;
  justify-content: space-between;
  padding-top: var(--spacing-md);
  padding-bottom: var(--spacing-md);
}

.logo {
  font-size: var(--font-size-2xl);
  font-weight: 800;
  background: linear-gradient(135deg, var(--color-primary) 0%, var(--color-accent) 100%);
  -webkit-background-clip: text;
  -webkit-text-fill-color: transparent;
  background-clip: text;
  /* Prevent logo from shrinking on small screens */
  flex-shrink: 0;
}

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

.nav-links a {
  font-weight: 500;
  color: var(--color-text-secondary);
  position: relative;
  /* Touch-friendly tap area */
  padding: var(--spacing-xs) 0;
}

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

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

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

.nav-actions {
  display: flex;
  align-items: center;
  gap: var(--spacing-md);
}

.theme-toggle,
.language-select {
  padding: var(--spacing-sm) var(--spacing-md);
  background: var(--color-bg-secondary);
  border-radius: var(--radius-md);
  font-size: var(--font-size-sm);
  font-weight: 500;
  color: var(--color-text-primary);
  border: 1px solid var(--color-border);
  cursor: pointer;
  /* Touch-friendly */
  min-height: 40px;
}

.theme-toggle:hover,
.language-select:hover {
  background: var(--color-bg-tertiary);
}

.mobile-menu-toggle {
  display: none;
  flex-direction: column;
  gap: 5px;
  padding: var(--spacing-sm);
  /* Touch-friendly minimum size */
  min-width: 44px;
  min-height: 44px;
  align-items: center;
  justify-content: center;
}

.mobile-menu-toggle span {
  width: 24px;
  height: 2px;
  background: var(--color-text-primary);
  transition: all var(--transition-base);
  display: block;
}

/* ===== MOBILE NAVIGATION ===== */
@media (max-width: 768px) {
  .navbar .container {
    padding-top: var(--spacing-sm);
    padding-bottom: var(--spacing-sm);
  }

  /* Hide desktop nav actions (theme/language) to save space; 
     move them inside the mobile menu if needed */
  .nav-actions {
    gap: var(--spacing-sm);
  }

  .theme-toggle,
  .language-select {
    padding: var(--spacing-xs) var(--spacing-sm);
    font-size: var(--font-size-xs);
  }

  .nav-links {
    position: fixed;
    top: 57px; /* aligns just below the navbar */
    left: 0;
    right: 0;
    flex-direction: column;
    align-items: flex-start;
    background: var(--color-surface);
    padding: var(--spacing-lg);
    gap: 0;
    border-bottom: 1px solid var(--color-border);
    box-shadow: var(--shadow-lg);
    transform: translateY(-110%);
    opacity: 0;
    pointer-events: none;
    transition: transform var(--transition-base), opacity var(--transition-base);
  }

  .nav-links.active {
    transform: translateY(0);
    opacity: 1;
    pointer-events: all;
  }

  /* Make each nav link a tall tap target */
  .nav-links li {
    width: 100%;
    border-bottom: 1px solid var(--color-border-light);
  }

  .nav-links li:last-child {
    border-bottom: none;
  }

  .nav-links a {
    display: block;
    width: 100%;
    padding: var(--spacing-md) 0;
    font-size: var(--font-size-lg);
  }

  .nav-links a::after {
    display: none; /* underline indicator doesn't work on stacked layout */
  }

  .mobile-menu-toggle {
    display: flex;
  }

  .mobile-menu-toggle.active span:nth-child(1) {
    transform: rotate(45deg) translate(5px, 5px);
  }

  .mobile-menu-toggle.active span:nth-child(2) {
    opacity: 0;
    transform: scaleX(0);
  }

  .mobile-menu-toggle.active span:nth-child(3) {
    transform: rotate(-45deg) translate(5px, -5px);
  }
}

/* ===== RESPONSIVE CONTAINER ===== */
@media (max-width: 768px) {
  .container {
    padding: 0 var(--spacing-md);
  }
}

@media (max-width: 480px) {
  .container {
    padding: 0 var(--spacing-sm);
  }
}

/* ===== RESPONSIVE GRIDS ===== */
@media (max-width: 640px) {
  /* Force single column on very small screens */
  .grid-2,
  .grid-3,
  .grid-4 {
    grid-template-columns: 1fr;
  }
}

/* ===== RESPONSIVE TYPOGRAPHY ===== */
@media (max-width: 768px) {
  .section-title {
    font-size: var(--font-size-3xl);
  }

  .section-subtitle {
    font-size: var(--font-size-base);
  }

  .logo {
    font-size: var(--font-size-xl);
  }
}

@media (max-width: 480px) {
  .section-title {
    font-size: var(--font-size-2xl);
  }

  .section {
    padding: var(--spacing-2xl) 0;
  }

  /* Stack buttons full-width on tiny screens */
  .btn {
    width: 100%;
    justify-content: center;
  }

  /* Unless explicitly set to auto */
  .btn-auto {
    width: auto;
  }
}