/* ==========================================
   CSS CUSTOM PROPERTIES (VARIABLES)
   ========================================== */
:root {
  /* Color Palette - Purple Gradient Theme */
  --primary-purple: #8B5CF6;
  --primary-pink: #EC4899;
  --dark-purple: #6D28D9;
  --light-purple: #A78BFA;
  --gradient-start: #8B5CF6;
  --gradient-end: #EC4899;

  /* Text Colors */
  --text-primary: #1F2937;
  --text-secondary: #6B7280;
  --text-light: #9CA3AF;

  /* Background Colors */
  --bg-white: #FFFFFF;
  --bg-gray: #F9FAFB;
  --bg-light-gray: #F3F4F6;

  /* Shadow Colors */
  --shadow-purple: rgba(139, 92, 246, 0.15);
  --shadow-purple-strong: rgba(139, 92, 246, 0.25);

  /* Typography */
  --font-primary: -apple-system, BlinkMacSystemFont, 'SF Pro Display', 'Segoe UI', 'Roboto', 'Helvetica Neue', sans-serif;
  --font-size-hero: 4rem;
  --font-size-h2: 2.5rem;
  --font-size-h3: 1.5rem;
  --font-size-body: 1rem;
  --font-size-small: 0.875rem;

  --font-weight-light: 300;
  --font-weight-regular: 400;
  --font-weight-medium: 500;
  --font-weight-semibold: 600;
  --font-weight-bold: 700;

  /* Spacing */
  --spacing-xs: 0.5rem;
  --spacing-sm: 1rem;
  --spacing-md: 2rem;
  --spacing-lg: 4rem;
  --spacing-xl: 6rem;

  /* Layout */
  --max-width: 1200px;
  --border-radius: 1rem;
  --border-radius-lg: 2rem;
  --border-radius-ios: 27%;

  /* Transitions */
  --transition-fast: 0.2s ease;
  --transition-normal: 0.3s ease;
  --transition-slow: 0.5s ease;
  --easing-smooth: cubic-bezier(0.4, 0.0, 0.2, 1);
  --easing-bounce: cubic-bezier(0.34, 1.56, 0.64, 1);
}

/* ==========================================
   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;
}

body {
  font-family: var(--font-primary);
  font-size: var(--font-size-body);
  line-height: 1.6;
  color: var(--text-primary);
  background: var(--bg-white);
  overflow-x: hidden;
}

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

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

/* ==========================================
   LAYOUT
   ========================================== */
.container {
  width: 100%;
  margin: 0 auto;
}

section {
  padding: var(--spacing-xl) var(--spacing-md);
}

.section-title {
  font-size: var(--font-size-h2);
  font-weight: var(--font-weight-bold);
  text-align: center;
  margin-bottom: var(--spacing-lg);
  background: linear-gradient(135deg, var(--gradient-start), var(--gradient-end));
  -webkit-background-clip: text;
  -webkit-text-fill-color: transparent;
  background-clip: text;
}

/* ==========================================
   HERO SECTION
   ========================================== */
#hero {
  display: flex;
  flex-direction: column;
  align-items: center;
  justify-content: center;
  min-height: 100vh;
  text-align: center;
  position: relative;
  padding: var(--spacing-lg) var(--spacing-md);
}

.hero-content {
  display: flex;
  flex-direction: column;
  align-items: center;
  gap: var(--spacing-md);
}

.hero-image {
  width: 280px;
  height: 280px;
  border-radius: 50%;
  object-fit: cover;
  box-shadow:
    0 20px 60px rgba(139, 92, 246, 0.3),
    0 0 0 8px rgba(139, 92, 246, 0.1);
  border: 4px solid var(--bg-white);
  will-change: transform;
}

.brand-name {
  font-size: var(--font-size-hero);
  font-weight: var(--font-weight-bold);
  background: linear-gradient(135deg, var(--gradient-start), var(--gradient-end));
  -webkit-background-clip: text;
  -webkit-text-fill-color: transparent;
  background-clip: text;
  letter-spacing: -0.02em;
  line-height: 1.1;
}

.tagline {
  font-size: var(--font-size-body);
  font-weight: var(--font-weight-light);
  color: var(--text-secondary);
  letter-spacing: 0.05em;
  max-width: 600px;
}

.scroll-indicator {
  position: absolute;
  bottom: var(--spacing-md);
  color: var(--text-light);
  opacity: 0.6;
  cursor: pointer;
  transition: opacity var(--transition-fast);
}

.scroll-indicator:hover {
  opacity: 1;
}

/* ==========================================
   APPS SECTION
   ========================================== */
#apps {
  background: var(--bg-gray);
  padding: var(--spacing-xl) var(--spacing-md);
}

.apps-grid {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(250px, 1fr));
  gap: var(--spacing-lg);
  max-width: var(--max-width);
  margin: 0 auto;
}

.app-card {
  background: var(--bg-white);
  border-radius: var(--border-radius-lg);
  padding: var(--spacing-lg);
  display: flex;
  flex-direction: column;
  align-items: center;
  text-align: center;
  box-shadow:
    0 4px 6px -1px rgba(0, 0, 0, 0.1),
    0 2px 4px -1px rgba(0, 0, 0, 0.06);
  transition:
    transform var(--transition-normal) var(--easing-smooth),
    box-shadow var(--transition-normal) var(--easing-smooth);
  transform-style: preserve-3d;
  position: relative;
  overflow: hidden;
}

.card-highlight {
  position: absolute;
  top: 0;
  left: 0;
  width: 100%;
  height: 100%;
  border-radius: var(--border-radius-lg);
  pointer-events: none;
  opacity: 0;
  transition: opacity var(--transition-normal);
  z-index: 1;
}

.app-card:hover .card-highlight {
  opacity: 1;
}

.app-icon {
  width: 120px;
  height: 120px;
  margin-bottom: var(--spacing-md);
  border-radius: var(--border-radius-ios);
  filter: drop-shadow(0 10px 20px rgba(0, 0, 0, 0.1));
  transition:
    transform var(--transition-slow) var(--easing-bounce),
    filter var(--transition-normal);
  position: relative;
  z-index: 2;
}

.app-name {
  font-size: var(--font-size-h3);
  font-weight: var(--font-weight-semibold);
  color: var(--text-primary);
  margin-bottom: var(--spacing-xs);
  position: relative;
  z-index: 2;
}

.app-description {
  font-size: var(--font-size-body);
  color: var(--text-secondary);
  margin-bottom: var(--spacing-md);
  flex-grow: 1;
  line-height: 1.5;
  position: relative;
  z-index: 2;
}

.download-btn {
  background: linear-gradient(135deg, var(--gradient-start), var(--gradient-end));
  color: #FFFFFF;
  padding: 0.75rem 2rem;
  border-radius: 2rem;
  font-weight: var(--font-weight-medium);
  font-size: var(--font-size-body);
  display: inline-flex;
  align-items: center;
  justify-content: center;
  gap: 0.5rem;
  box-shadow:
    0 10px 25px -5px var(--shadow-purple),
    0 4px 6px -2px var(--shadow-purple);
  transition:
    transform var(--transition-fast) var(--easing-smooth),
    box-shadow var(--transition-fast) var(--easing-smooth);
  cursor: pointer;
  border: none;
  position: relative;
  z-index: 2;
}

.download-btn svg {
  width: 16px;
  height: 16px;
  color: #FFFFFF;
  fill: #FFFFFF;
}

.download-btn:hover {
  transform: translateY(-2px) scale(1.02);
  box-shadow:
    0 15px 35px -5px var(--shadow-purple-strong),
    0 8px 10px -4px var(--shadow-purple);
}

.download-btn:active {
  transform: translateY(0) scale(0.98);
  box-shadow:
    0 5px 15px -5px var(--shadow-purple),
    0 2px 4px -2px var(--shadow-purple);
}

/* ==========================================
   SOCIAL SECTION
   ========================================== */
#social {
  padding: var(--spacing-xl) var(--spacing-md);
  text-align: center;
  background: var(--bg-white);
}

.social-links {
  display: flex;
  justify-content: center;
  align-items: center;
  gap: var(--spacing-md);
  flex-wrap: wrap;
}

.social-btn {
  width: 60px;
  height: 60px;
  border-radius: 50%;
  display: flex;
  align-items: center;
  justify-content: center;
  color: var(--bg-white);
  box-shadow:
    0 4px 6px -1px rgba(0, 0, 0, 0.1),
    0 2px 4px -1px rgba(0, 0, 0, 0.06);
  transition:
    transform var(--transition-fast) var(--easing-smooth),
    box-shadow var(--transition-fast) var(--easing-smooth);
  cursor: pointer;
}

.social-btn svg {
  width: 24px;
  height: 24px;
}

.social-btn.youtube {
  background: linear-gradient(135deg, #FF0000, #CC0000);
}

.social-btn.instagram {
  background: linear-gradient(135deg, #F58529, #DD2A7B, #8134AF, #515BD4);
}

.social-btn.twitter {
  background: linear-gradient(135deg, #1DA1F2, #0D8BD9);
}

.social-btn:hover {
  transform: scale(1.15) rotate(5deg);
  box-shadow:
    0 15px 30px -5px rgba(0, 0, 0, 0.2),
    0 8px 12px -4px rgba(0, 0, 0, 0.1);
}

.social-btn:active {
  transform: scale(1.05);
}

/* ==========================================
   FOOTER
   ========================================== */
footer {
  padding: var(--spacing-md);
  color: var(--text-secondary);
  font-size: var(--font-size-small);
  background: var(--bg-gray);
  border-top: 1px solid var(--bg-light-gray);
}

.footer-content {
  display: flex;
  justify-content: space-between;
  align-items: center;
  max-width: var(--max-width);
  margin: 0 auto;
  flex-wrap: wrap;
  gap: var(--spacing-sm);
}

.copyright {
  margin: 0;
}

.footer-links {
  display: flex;
  gap: var(--spacing-md);
  flex-wrap: wrap;
}

.footer-links a {
  color: var(--text-secondary);
  text-decoration: none;
  transition: color var(--transition-fast);
  position: relative;
}

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

.footer-links a::after {
  content: '';
  position: absolute;
  width: 0;
  height: 2px;
  bottom: -2px;
  left: 0;
  background: linear-gradient(135deg, var(--gradient-start), var(--gradient-end));
  transition: width var(--transition-normal);
}

.footer-links a:hover::after {
  width: 100%;
}

/* Active page indicator */
.footer-links a.active {
  color: var(--primary-purple);
  font-weight: var(--font-weight-semibold);
}

.footer-links a.active::after {
  width: 100%;
}

/* ==========================================
   UTILITY CLASSES
   ========================================== */
.hidden {
  opacity: 0;
  visibility: hidden;
}

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

/* Focus styles for accessibility */
a:focus-visible,
button:focus-visible {
  outline: 3px solid var(--primary-purple);
  outline-offset: 3px;
  border-radius: 4px;
}