/* ============================================
   PromoPal Landing Page - Styles
   Mobile-First Responsive Design with Dark Mode
   ============================================ */

/* ============================================
   CSS Reset & Base Styles
   ============================================ */

*, *::before, *::after {
  box-sizing: border-box;
  margin: 0;
  padding: 0;
}

html {
  scroll-behavior: smooth;
  -webkit-font-smoothing: antialiased;
  -moz-osx-font-smoothing: grayscale;
}

/* ============================================
   CSS Custom Properties - Light Theme
   ============================================ */

:root {
  /* Colors - Light Theme */
  --color-primary: #1A73E8;
  --color-primary-light: #EFF3FB;
  --color-primary-dark: #1557B0;
  --color-gradient-start: #1A73E8;
  --color-gradient-end: #5C9CE6;

  --color-background: #F8F9FA;
  --color-surface: #FFFFFF;
  --color-surface-variant: #F5F5F5;

  --color-text-primary: #212121;
  --color-text-secondary: #616161;
  --color-text-tertiary: #757575;
  --color-text-disabled: #9E9E9E;

  --color-border-light: #F0F0F0;
  --color-border-medium: #E0E0E0;
  --color-border-dark: #BDBDBD;

  --color-accent: #F8961E;
  --color-accent-light: #FFF3E0;
  --color-gold: #8B5A00;

  --color-success: #2E7D32;
  --color-error: #D32F2F;
  --color-warning: #FF9800;
  --color-info: #1976D2;

  /* Shadows - Light Theme */
  --shadow-card: 0 2px 8px rgba(0, 0, 0, 0.08);
  --shadow-card-hover: 0 8px 24px rgba(0, 0, 0, 0.12);
  --shadow-button-hover: 0 4px 12px rgba(26, 115, 232, 0.25);

  /* Spacing */
  --spacing-xs: 4px;
  --spacing-sm: 8px;
  --spacing-md: 12px;
  --spacing-lg: 16px;
  --spacing-xl: 20px;
  --spacing-2xl: 24px;
  --spacing-3xl: 32px;
  --spacing-4xl: 48px;
  --spacing-5xl: 64px;
  --spacing-6xl: 80px;

  /* Typography */
  --font-family: 'Inter', -apple-system, BlinkMacSystemFont, 'Segoe UI', Roboto, sans-serif;
  --font-weight-regular: 400;
  --font-weight-medium: 500;
  --font-weight-semibold: 600;

  --font-size-display: 48px;
  --font-size-h1: 36px;
  --font-size-h2: 28px;
  --font-size-h3: 24px;
  --font-size-body-large: 18px;
  --font-size-body: 16px;
  --font-size-body-small: 14px;
  --font-size-caption: 12px;
  --font-size-button: 16px;

  --line-height-heading: 1.2;
  --line-height-heading-secondary: 1.3;
  --line-height-body: 1.5;
  --line-height-caption: 1.4;

  /* Border Radius */
  --radius-small: 8px;
  --radius-medium: 12px;
  --radius-large: 20px;
  --radius-full: 9999px;

  /* Layout */
  --container-max-width: 1200px;
  --container-padding: 24px;
  --section-padding-vertical: 80px;
  --section-padding-mobile: 48px;

  /* Animations */
  --duration-fast: 0.2s;
  --duration-medium: 0.3s;
  --duration-slow: 0.6s;
  --easing-default: ease;
  --easing-in-out: ease-in-out;
  --easing-out: ease-out;
}

/* ============================================
   Dark Mode - Override Variables
   ============================================ */

@media (prefers-color-scheme: dark) {
  :root {
    --color-primary: #4A9EFF;
    --color-primary-light: #1E2A3A;
    --color-primary-dark: #357ABD;

    --color-background: #0D1117;
    --color-surface: #161B22;
    --color-surface-variant: #1C2128;

    --color-text-primary: #E6EDF3;
    --color-text-secondary: #B1BAC4;
    --color-text-tertiary: #BFC4C9;
    --color-text-disabled: #6E7681;

    --color-border-light: #21262D;
    --color-border-medium: #30363D;
    --color-border-dark: #484F58;

    --color-accent: #FFA94D;
    --color-accent-light: #2D1F0A;
    --color-gold: #FFB700;

    --color-success: #3FB950;
    --color-error: #F85149;
    --color-warning: #F0883E;
    --color-info: #58A6FF;

    --shadow-card: 0 2px 8px rgba(0, 0, 0, 0.3);
    --shadow-card-hover: 0 8px 24px rgba(0, 0, 0, 0.4);
  }
}

/* ============================================
   Base Typography
   ============================================ */

body {
  font-family: var(--font-family);
  font-size: var(--font-size-body);
  font-weight: var(--font-weight-regular);
  line-height: var(--line-height-body);
  color: var(--color-text-primary);
  background-color: var(--color-background);
}

h1, h2, h3, h4, h5, h6 {
  font-weight: var(--font-weight-semibold);
  line-height: var(--line-height-heading);
  color: var(--color-text-primary);
}

p {
  margin: 0;
}

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

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

/* ============================================
   Utility Classes
   ============================================ */

.container {
  max-width: var(--container-max-width);
  margin: 0 auto;
  padding: 0 var(--container-padding);
}

.section-heading {
  font-size: var(--font-size-h2);
  font-weight: var(--font-weight-semibold);
  line-height: var(--line-height-heading-secondary);
  color: var(--color-text-primary);
  text-align: center;
  margin-bottom: var(--spacing-lg);
}

.section-subheading {
  font-size: var(--font-size-body-large);
  font-weight: var(--font-weight-regular);
  line-height: var(--line-height-body);
  color: var(--color-text-secondary);
  text-align: center;
  margin-bottom: var(--spacing-4xl);
}

/* ============================================
   Hero Section
   ============================================ */

.hero {
  background: linear-gradient(135deg, var(--color-gradient-start) 0%, var(--color-gradient-end) 100%);
  min-height: 100vh;
  display: flex;
  align-items: center;
  justify-content: center;
  padding: var(--section-padding-mobile) var(--container-padding);
  text-align: center;
  position: relative;
}

.hero-content {
  max-width: 800px;
  margin: 0 auto;
}

.hero-logo {
  width: 100px;
  height: 100px;
  margin: 0 auto var(--spacing-2xl);
  border-radius: var(--radius-large);
}

.hero-title {
  font-size: 32px;
  font-weight: var(--font-weight-semibold);
  line-height: var(--line-height-heading);
  color: #FFFFFF;
  margin-bottom: var(--spacing-lg);
}

.hero-description {
  font-size: var(--font-size-body);
  font-weight: var(--font-weight-regular);
  line-height: var(--line-height-body);
  color: #FFFFFF;
  opacity: 0.95;
  margin-bottom: var(--spacing-3xl);
}

.app-badges {
  display: flex;
  gap: var(--spacing-lg);
  justify-content: center;
  align-items: center;
  flex-wrap: wrap;
  flex-direction: column;
}

.apple-badge {
  height: 73px;
}

.badge-link {
  display: inline-block;
  transition: transform var(--duration-fast) var(--easing-default);
}

.badge-link:hover {
  transform: translateY(-2px);
}

.badge-link:focus-visible {
  outline: 2px solid #FFFFFF;
  outline-offset: 4px;
  border-radius: var(--radius-small);
}

.app-badge {
  border-radius: var(--radius-small);
}

/* ============================================
   Scroll Indicator
   ============================================ */

.scroll-indicator {
  position: absolute;
  bottom: var(--spacing-3xl);
  left: 50%;
  transform: translateX(-50%);
  display: flex;
  flex-direction: column;
  align-items: center;
  gap: var(--spacing-sm);
  cursor: pointer;
  opacity: 1;
  transition: opacity var(--duration-medium) var(--easing-default);
  z-index: 10;
}

.scroll-indicator.hidden {
  opacity: 0;
  pointer-events: none;
}

.scroll-text {
  font-size: var(--font-size-body-small);
  font-weight: var(--font-weight-medium);
  color: #FFFFFF;
  text-transform: uppercase;
  letter-spacing: 1px;
  opacity: 0.7;
  animation: fadeInOut 2s var(--easing-in-out) infinite;
}

.scroll-chevron {
  color: #FFFFFF;
  animation: bounce 2s var(--easing-in-out) infinite;
}

.scroll-indicator:hover .scroll-text,
.scroll-indicator:hover .scroll-chevron {
  animation-play-state: paused;
  opacity: 1;
}

.scroll-indicator:focus-visible {
  outline: 2px solid #FFFFFF;
  outline-offset: 4px;
  border-radius: var(--radius-small);
}

/* Scroll Indicator Animations */
@keyframes bounce {
  0%, 100% {
    transform: translateY(0);
  }
  50% {
    transform: translateY(8px);
  }
}

@keyframes fadeInOut {
  0%, 100% {
    opacity: 0.7;
  }
  50% {
    opacity: 1;
  }
}

/* ============================================
   Features Section
   ============================================ */

.features {
  padding: var(--section-padding-mobile) 0;
  background-color: var(--color-background);
}

.features-grid {
  display: grid;
  grid-template-columns: 1fr;
  gap: var(--spacing-2xl);
  margin-top: var(--spacing-4xl);
}

.feature-card {
  background: var(--color-surface);
  border: 1px solid var(--color-border-medium);
  border-radius: var(--radius-medium);
  padding: var(--spacing-2xl);
  box-shadow: var(--shadow-card);
  transition: transform var(--duration-medium) var(--easing-default),
              box-shadow var(--duration-medium) var(--easing-default);
}

.feature-card:hover {
  transform: translateY(-4px);
  box-shadow: var(--shadow-card-hover);
}

.feature-icon {
  width: 48px;
  height: 48px;
  margin-bottom: var(--spacing-lg);
  color: var(--color-primary);
}

.feature-title {
  font-size: var(--font-size-h3);
  font-weight: var(--font-weight-semibold);
  line-height: var(--line-height-heading-secondary);
  color: var(--color-text-primary);
  margin-bottom: var(--spacing-sm);
}

.feature-description {
  font-size: var(--font-size-body);
  font-weight: var(--font-weight-regular);
  line-height: var(--line-height-body);
  color: var(--color-text-secondary);
}

/* ============================================
   Benefits Section
   ============================================ */

.benefits {
  padding: var(--section-padding-mobile) 0;
  background-color: var(--color-surface);
}

.benefits-list {
  display: grid;
  grid-template-columns: 1fr;
  gap: var(--spacing-3xl);
  max-width: 900px;
  margin: 0 auto;
}

.benefit-item {
  display: flex;
  gap: var(--spacing-lg);
  align-items: flex-start;
}

.benefit-emoji {
  font-size: 32px;
  flex-shrink: 0;
  line-height: 1;
}

.benefit-content {
  flex: 1;
}

.benefit-title {
  font-size: var(--font-size-h3);
  font-weight: var(--font-weight-semibold);
  line-height: var(--line-height-heading-secondary);
  color: var(--color-text-primary);
  margin-bottom: var(--spacing-xs);
}

.benefit-description {
  font-size: var(--font-size-body);
  font-weight: var(--font-weight-regular);
  line-height: var(--line-height-body);
  color: var(--color-text-secondary);
}

/* ============================================
   How It Works Section
   ============================================ */

.how-it-works {
  padding: var(--section-padding-mobile) 0;
  background-color: var(--color-background);
}

.steps-container {
  display: grid;
  grid-template-columns: 1fr;
  gap: var(--spacing-4xl);
  margin-top: var(--spacing-4xl);
  max-width: 900px;
  margin-left: auto;
  margin-right: auto;
}

.step {
  text-align: center;
}

.step-number {
  width: 64px;
  height: 64px;
  background-color: var(--color-primary);
  color: #FFFFFF;
  font-size: var(--font-size-h2);
  font-weight: var(--font-weight-semibold);
  border-radius: var(--radius-full);
  display: flex;
  align-items: center;
  justify-content: center;
  margin: 0 auto var(--spacing-lg);
}

.step-title {
  font-size: var(--font-size-h3);
  font-weight: var(--font-weight-semibold);
  line-height: var(--line-height-heading-secondary);
  color: var(--color-text-primary);
  margin-bottom: var(--spacing-sm);
}

.step-description {
  font-size: var(--font-size-body);
  font-weight: var(--font-weight-regular);
  line-height: var(--line-height-body);
  color: var(--color-text-secondary);
}

/* ============================================
   Download CTA Section
   ============================================ */

.download-cta {
  padding: var(--section-padding-mobile) 0;
  background: linear-gradient(135deg, var(--color-gradient-start) 0%, var(--color-gradient-end) 100%);
  text-align: center;
}

.cta-content {
  max-width: 800px;
  margin: 0 auto;
}

.cta-heading {
  font-size: var(--font-size-h1);
  font-weight: var(--font-weight-semibold);
  line-height: var(--line-height-heading);
  color: #FFFFFF;
  margin-bottom: var(--spacing-lg);
}

.cta-description {
  font-size: var(--font-size-body-large);
  font-weight: var(--font-weight-regular);
  line-height: var(--line-height-body);
  color: #FFFFFF;
  opacity: 0.95;
  margin-bottom: var(--spacing-3xl);
}

.compatibility-note {
  font-size: var(--font-size-body-small);
  color: #FFFFFF;
  opacity: 0.8;
  margin-top: var(--spacing-2xl);
}

/* ============================================
   Footer
   ============================================ */

.footer {
  padding: var(--spacing-4xl) 0;
  background-color: var(--color-surface);
  border-top: 1px solid var(--color-border-light);
}

.footer-content {
  text-align: center;
}

.footer-links {
  display: flex;
  justify-content: center;
  align-items: center;
  flex-wrap: wrap;
  gap: var(--spacing-sm);
  margin-bottom: var(--spacing-lg);
}

.footer-link {
  font-size: var(--font-size-body-small);
  color: var(--color-text-secondary);
  transition: color var(--duration-fast) var(--easing-default);
}

.footer-link:hover {
  color: var(--color-primary);
}

.footer-link:focus-visible {
  outline: 2px solid var(--color-primary);
  outline-offset: 2px;
  border-radius: var(--radius-small);
}

.footer-separator {
  color: var(--color-text-tertiary);
}

.footer-copyright {
  font-size: var(--font-size-body-small);
  color: var(--color-text-secondary);
  margin-bottom: var(--spacing-sm);
}

.footer-version {
  font-size: var(--font-size-caption);
  color: var(--color-text-tertiary);
}

/* ============================================
   Scroll Animations
   ============================================ */

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

.fade-in {
  animation: fadeInUp 0.6s var(--easing-out) forwards;
}

/* Prepare elements for animation */
.feature-card,
.benefit-item,
.step {
  opacity: 0;
}

/* If animations are disabled or already visible, show elements */
.no-js .feature-card,
.no-js .benefit-item,
.no-js .step {
  opacity: 1;
}

/* ============================================
   Accessibility - Reduced Motion
   ============================================ */

@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;
  }

  /* Show all elements immediately when motion is reduced */
  .feature-card,
  .benefit-item,
  .step {
    opacity: 1 !important;
  }

  /* Disable scroll indicator animations */
  .scroll-text,
  .scroll-chevron {
    animation: none !important;
  }
}

/* ============================================
   Accessibility - Focus Indicators
   ============================================ */

*:focus-visible {
  outline: 2px solid var(--color-primary);
  outline-offset: 2px;
}

/* ============================================
   Responsive - Tablet (768px+)
   ============================================ */

@media (min-width: 768px) {
  /* Typography */
  .hero-title {
    font-size: 40px;
  }

  .section-heading {
    font-size: var(--font-size-h2);
  }

  /* Hero Section */
  .app-badges {
    flex-direction: row;
  }

  /* Scroll Indicator */
  .scroll-indicator {
    bottom: var(--spacing-4xl);
  }

  /* Features Grid */
  .features-grid {
    grid-template-columns: repeat(2, 1fr);
  }

  /* Benefits */
  .benefits-list {
    grid-template-columns: repeat(2, 1fr);
  }

  /* Steps */
  .steps-container {
    gap: var(--spacing-3xl);
  }
}

/* ============================================
   Responsive - Desktop (1024px+)
   ============================================ */

@media (min-width: 1024px) {
  /* Typography */
  .hero-title {
    font-size: var(--font-size-display);
  }

  .hero-description {
    font-size: var(--font-size-body-large);
  }

  .section-heading {
    font-size: var(--font-size-h1);
  }

  .feature-title {
    font-size: var(--font-size-h3);
  }

  .step-title {
    font-size: var(--font-size-h3);
  }

  .cta-heading {
    font-size: var(--font-size-h1);
  }

  /* Section Spacing */
  .hero {
    padding: var(--section-padding-vertical) var(--container-padding);
  }

  .features,
  .benefits,
  .how-it-works,
  .download-cta {
    padding: var(--section-padding-vertical) 0;
  }

  /* Scroll Indicator */
  .scroll-indicator {
    bottom: var(--spacing-5xl);
  }

  /* Features Grid */
  .features-grid {
    grid-template-columns: repeat(3, 1fr);
  }

  /* Benefits */
  .benefit-emoji {
    font-size: 40px;
  }

  /* Steps - Horizontal Layout */
  .steps-container {
    grid-template-columns: repeat(3, 1fr);
    gap: var(--spacing-2xl);
  }

  /* Footer */
  .footer-links {
    gap: var(--spacing-lg);
  }
}

/* ============================================
   Print Styles
   ============================================ */

@media print {
  .hero,
  .download-cta {
    background: white;
    color: black;
  }

  .app-badges {
    display: none;
  }

  .footer-links {
    display: none;
  }
}