/* CSS Custom Properties for Theme Variables */
:root {
  /* Light Mode Colors */
  --primary-color: #003b6f;
  --primary-light: #0056b3;
  --primary-dark: #002850;
  --accent-color: #512BD4;
  
  /* Neutral Colors */
  --bg-primary: #ffffff;
  --bg-secondary: #f8f9fa;
  --bg-tertiary: #e9ecef;
  --text-primary: #212529;
  --text-secondary: #6c757d;
  --text-muted: #adb5bd;
  --border-color: #dee2e6;
  --shadow-light: rgba(0, 59, 111, 0.1);
  --shadow-medium: rgba(0, 59, 111, 0.15);
  --shadow-strong: rgba(0, 59, 111, 0.2);
  
  /* Success/Error Colors */
  --success-color: #28a745;
  --warning-color: #ffc107;
  --error-color: #dc3545;
  
  /* Layout */
  --container-max-width: 1200px;
  --border-radius: 12px;
  --border-radius-small: 8px;
  --transition-speed: 0.3s;
}

/* Dark Mode Variables */
[data-theme="dark"] {
  --bg-primary: #1a1d23;
  --bg-secondary: #22262e;
  --bg-tertiary: #2a2f39;
  --text-primary: #e9ecef;
  --text-secondary: #adb5bd;
  --text-muted: #6c757d;
  --border-color: #495057;
  --shadow-light: rgba(0, 0, 0, 0.3);
  --shadow-medium: rgba(0, 0, 0, 0.4);
  --shadow-strong: rgba(0, 0, 0, 0.5);
}

/* Base Styles */
* {
  margin: 0;
  padding: 0;
  box-sizing: border-box;
}

html {
  scroll-behavior: smooth;
  font-size: 16px;
}

body {
  font-family: -apple-system, BlinkMacSystemFont, 'Segoe UI', Roboto, Oxygen, Ubuntu, Cantarell, sans-serif;
  line-height: 1.6;
  color: var(--text-primary);
  background-color: var(--bg-primary);
  transition: background-color var(--transition-speed), color var(--transition-speed);
}

.container {
  max-width: var(--container-max-width);
  margin: 0 auto;
  padding: 0 20px;
}

/* Typography */
h1, h2, h3 {
  font-weight: 700;
  line-height: 1.2;
  margin-bottom: 1rem;
}

h1 { font-size: 3rem; }
h2 { font-size: 2.5rem; }
h3 { font-size: 1.5rem; }

p {
  margin-bottom: 1rem;
}

/* Navigation */
.header {
  background-color: var(--bg-primary);
  border-bottom: 1px solid var(--border-color);
  position: sticky;
  top: 0;
  z-index: 1000;
  backdrop-filter: blur(10px);
  background-color: rgba(var(--bg-primary), 0.95);
}

.nav {
  display: flex;
  justify-content: space-between;
  align-items: center;
  padding: 1rem 2rem;
  max-width: var(--container-max-width);
  margin: 0 auto;
}

.nav-brand {
  display: flex;
  align-items: center;
  gap: 0.5rem;
}

.brand-text {
  font-size: 1.5rem;
  font-weight: 700;
  color: var(--primary-color);
}

.platform-badge {
  background-color: var(--accent-color);
  color: white;
  padding: 0.25rem 0.5rem;
  border-radius: var(--border-radius-small);
  font-size: 0.75rem;
  font-weight: 600;
}

.nav-menu {
  display: flex;
  align-items: center;
  gap: 2rem;
}

.nav-link {
  color: var(--text-secondary);
  text-decoration: none;
  font-weight: 500;
  transition: color var(--transition-speed);
}

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

.theme-toggle {
  background: none;
  border: none;
  font-size: 1.25rem;
  cursor: pointer;
  padding: 0.5rem;
  border-radius: 50%;
  transition: background-color var(--transition-speed);
}

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

/* Buttons */
.btn {
  display: inline-flex;
  align-items: center;
  gap: 0.5rem;
  padding: 0.75rem 1.5rem;
  border: none;
  border-radius: var(--border-radius);
  font-size: 1rem;
  font-weight: 600;
  text-decoration: none;
  cursor: pointer;
  transition: all var(--transition-speed);
  text-align: center;
}

.btn-primary {
  background-color: var(--primary-color);
  color: white;
}

.btn-primary:hover:not(:disabled) {
  background-color: var(--primary-light);
  transform: translateY(-2px);
  box-shadow: 0 8px 25px var(--shadow-medium);
}

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

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

.btn:disabled {
  opacity: 0.6;
  cursor: not-allowed;
  transform: none;
}

/* Hero Section */
.hero {
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: 4rem;
  align-items: center;
  padding: 4rem 2rem;
  min-height: 80vh;
  background: linear-gradient(135deg, var(--bg-primary) 0%, var(--bg-secondary) 100%);
}

.hero-content {
  max-width: 600px;
}

.hero-title {
  color: var(--primary-color);
  margin-bottom: 1rem;
}

.hero-tagline {
  font-size: 1.5rem;
  color: var(--text-secondary);
  margin-bottom: 1.5rem;
}

.hero-description {
  font-size: 1.125rem;
  color: var(--text-secondary);
  margin-bottom: 2rem;
}

.hero-actions {
  display: flex;
  gap: 1rem;
  flex-wrap: wrap;
}

.hero-image {
  display: flex;
  justify-content: center;
  align-items: center;
}

.phone-mockup {
  width: 300px;
  height: 600px;
  background: var(--bg-secondary);
  border-radius: 40px;
  padding: 10px;
  box-shadow: 0 25px 50px var(--shadow-strong);
  border: 3px solid var(--border-color);
  position: relative;
}

.phone-screen {
  width: 100%;
  height: 100%;
  background: var(--bg-primary);
  border-radius: 30px;
  overflow: hidden;
  display: flex;
  align-items: center;
  justify-content: center;
}

.app-screenshot {
  width: 100%;
  height: 100%;
  object-fit: cover;
}

/* Sections */
.features,
.screenshots,
.technical,
.installation,
.download {
  padding: 5rem 0;
}

.section-title {
  text-align: center;
  color: var(--primary-color);
  margin-bottom: 3rem;
  font-size: 2.5rem;
}

/* Features Grid */
.features-grid {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(350px, 1fr));
  gap: 2rem;
}

.feature-card {
  background: var(--bg-secondary);
  padding: 2rem;
  border-radius: var(--border-radius);
  border: 1px solid var(--border-color);
  transition: transform var(--transition-speed), box-shadow var(--transition-speed);
}

.feature-card:hover {
  transform: translateY(-5px);
  box-shadow: 0 15px 35px var(--shadow-medium);
}

.feature-icon {
  font-size: 3rem;
  margin-bottom: 1rem;
  display: block;
}

.feature-title {
  color: var(--primary-color);
  margin-bottom: 1rem;
}

.feature-description {
  color: var(--text-secondary);
}

/* Screenshots Grid */
.screenshots-grid {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(250px, 1fr));
  gap: 2rem;
}

.screenshot-card {
  background: var(--bg-secondary);
  border-radius: var(--border-radius);
  padding: 1rem;
  border: 1px solid var(--border-color);
  text-align: center;
  transition: transform var(--transition-speed);
}

.screenshot-card:hover {
  transform: scale(1.05);
}

.screenshot-img {
  width: 100%;
  height: 400px;
  object-fit: cover;
  border-radius: var(--border-radius-small);
  margin-bottom: 1rem;
  background: var(--bg-tertiary);
}

.screenshot-card h3 {
  color: var(--primary-color);
  margin-bottom: 0.5rem;
}

.screenshot-card p {
  color: var(--text-secondary);
  font-size: 0.9rem;
}

/* Technical Grid */
.technical-grid {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(250px, 1fr));
  gap: 2rem;
}

.tech-card {
  background: var(--bg-secondary);
  padding: 2rem;
  border-radius: var(--border-radius);
  border: 1px solid var(--border-color);
}

.tech-card h3 {
  color: var(--primary-color);
  margin-bottom: 1rem;
}

.tech-card p {
  color: var(--text-secondary);
}

/* Installation Section */
.installation {
  background: var(--bg-secondary);
}

.installation-content {
  max-width: 800px;
  margin: 0 auto;
  text-align: center;
}

.instructions ol {
  text-align: left;
  max-width: 600px;
  margin: 0 auto 2rem;
  padding-left: 2rem;
}

.instructions li {
  margin-bottom: 1rem;
  color: var(--text-secondary);
}

.note {
  background: var(--accent-color);
  color: white;
  padding: 1.5rem;
  border-radius: var(--border-radius);
  margin-top: 2rem;
}

.note p {
  margin: 0;
}

/* Download Section */
.download {
  background: linear-gradient(135deg, var(--primary-color) 0%, var(--primary-dark) 100%);
  color: white;
  text-align: center;
}

.download .section-title {
  color: white;
}

.download-card {
  background: rgba(255, 255, 255, 0.1);
  backdrop-filter: blur(10px);
  border-radius: var(--border-radius);
  padding: 3rem;
  max-width: 600px;
  margin: 0 auto;
  border: 1px solid rgba(255, 255, 255, 0.2);
}

.app-info {
  display: flex;
  justify-content: center;
  gap: 2rem;
  margin-bottom: 2rem;
  flex-wrap: wrap;
}

.version, .platform, .package {
  background: rgba(255, 255, 255, 0.2);
  padding: 0.5rem 1rem;
  border-radius: var(--border-radius-small);
  font-size: 0.9rem;
}

.download-btn {
  background: white;
  color: var(--primary-color);
  padding: 1rem 2rem;
  font-size: 1.25rem;
  margin-bottom: 1rem;
  display: inline-flex;
  flex-direction: column;
  align-items: center;
  gap: 0.5rem;
}

.btn-text {
  font-weight: 700;
}

.btn-size {
  font-size: 0.9rem;
  opacity: 0.7;
}

.coming-soon {
  color: var(--warning-color);
  font-weight: 600;
  margin-bottom: 1rem;
}

.distribution-note {
  opacity: 0.8;
  font-size: 0.9rem;
}

/* Footer */
.footer {
  background: var(--bg-secondary);
  border-top: 1px solid var(--border-color);
  padding: 3rem 0;
}

.footer-content {
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: 2rem;
  align-items: center;
}

.footer-info p,
.footer-credits p {
  margin-bottom: 0.5rem;
  color: var(--text-secondary);
}

.footer-info p strong,
.footer-credits p strong {
  color: var(--text-primary);
}

.contact-placeholder {
  opacity: 0.7;
  font-style: italic;
}

/* Responsive Design */
@media (max-width: 768px) {
  .nav {
    padding: 1rem;
  }
  
  .nav-menu {
    gap: 1rem;
  }
  
  .nav-link:not(.theme-toggle) {
    display: none;
  }
  
  .hero {
    grid-template-columns: 1fr;
    text-align: center;
    padding: 2rem 1rem;
  }
  
  .hero-title {
    font-size: 2rem;
  }
  
  .hero-tagline {
    font-size: 1.25rem;
  }
  
  .hero-actions {
    justify-content: center;
  }
  
  .phone-mockup {
    width: 250px;
    height: 500px;
  }
  
  .features-grid,
  .screenshots-grid,
  .technical-grid {
    grid-template-columns: 1fr;
  }
  
  .footer-content {
    grid-template-columns: 1fr;
    text-align: center;
  }
  
  .app-info {
    flex-direction: column;
    gap: 0.5rem;
  }
}

@media (max-width: 480px) {
  .container {
    padding: 0 15px;
  }
  
  h1 { font-size: 2rem; }
  h2 { font-size: 1.75rem; }
  h3 { font-size: 1.25rem; }
  
  .hero {
    min-height: auto;
  }
  
  .phone-mockup {
    width: 200px;
    height: 400px;
  }
}