/* Modern CSS Reset */
*, *::before, *::after {
  box-sizing: border-box;
  margin: 0;
  padding: 0;
}

/* CSS Variables for Easy Theming */
:root {
  --primary-color: #2563eb;
  --primary-dark: #1e40af;
  --secondary-color: #8b5cf6;
  --accent-color: #06b6d4;
  --text-dark: #1f2937;
  --text-light: #6b7280;
  --bg-light: #f9fafb;
  --bg-white: #ffffff;
  --border-color: #e5e7eb;
  --success-color: #10b981;
  --shadow-sm: 0 1px 2px 0 rgba(0, 0, 0, 0.05);
  --shadow-md: 0 4px 6px -1px rgba(0, 0, 0, 0.1);
  --shadow-lg: 0 10px 15px -3px rgba(0, 0, 0, 0.1);
  --shadow-xl: 0 20px 25px -5px rgba(0, 0, 0, 0.1);
  --radius-sm: 0.375rem;
  --radius-md: 0.5rem;
  --radius-lg: 0.75rem;
  --radius-xl: 1rem;
}

/* Base Styles */
html {
  scroll-behavior: smooth;
  font-size: 16px;
}

body {
  font-family: -apple-system, BlinkMacSystemFont, 'Segoe UI', Roboto, 'Helvetica Neue', Arial, sans-serif;
  line-height: 1.6;
  color: var(--text-dark);
  background-color: var(--bg-white);
  overflow-x: hidden;
}

/* Typography */
h1, h2, h3, h4, h5, h6 {
  font-weight: 700;
  line-height: 1.2;
  margin-bottom: 1rem;
  color: var(--text-dark);
}

h1 { font-size: 2.5rem; }
h2 { font-size: 2rem; }
h3 { font-size: 1.5rem; }
h4 { font-size: 1.25rem; }
h5 { font-size: 1.125rem; }
h6 { font-size: 1rem; }

p {
  margin-bottom: 1rem;
  color: var(--text-light);
}

a {
  color: var(--primary-color);
  text-decoration: none;
  transition: color 0.3s ease;
}

a:hover {
  color: var(--primary-dark);
}

/* Header */
header {
  background: var(--bg-white);
  box-shadow: var(--shadow-sm);
  position: sticky;
  top: 0;
  z-index: 1000;
  border-bottom: 1px solid var(--border-color);
}

.header-container {
  max-width: 1200px;
  margin: 0 auto;
  padding: 1rem 2rem;
  display: flex;
  justify-content: space-between;
  align-items: center;
}

.logo {
  font-size: 1.5rem;
  font-weight: 700;
  color: var(--primary-color);
  text-decoration: none;
}

.logo:hover {
  color: var(--primary-dark);
}

nav ul {
  list-style: none;
  display: flex;
  gap: 2rem;
  align-items: center;
}

nav a {
  color: var(--text-dark);
  font-weight: 500;
  transition: color 0.3s ease;
}

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

/* Mobile Menu Toggle */
.menu-toggle {
  display: none;
  background: none;
  border: none;
  font-size: 1.5rem;
  cursor: pointer;
  color: var(--text-dark);
}

/* Hero/Banner Section */
.hero {
  background: linear-gradient(135deg, var(--primary-color) 0%, var(--secondary-color) 100%);
  color: white;
  padding: 6rem 2rem;
  text-align: center;
}

.hero h1 {
  color: white;
  font-size: 3rem;
  margin-bottom: 1rem;
}

.hero p {
  color: rgba(255, 255, 255, 0.9);
  font-size: 1.25rem;
  max-width: 600px;
  margin: 0 auto;
}

/* Container */
.container {
  max-width: 1200px;
  margin: 0 auto;
  padding: 0 2rem;
}

/* Section */
section {
  padding: 4rem 2rem;
}

.section-title {
  text-align: center;
  margin-bottom: 3rem;
}

.section-title h2 {
  font-size: 2.5rem;
  margin-bottom: 0.5rem;
}

.section-title p {
  font-size: 1.125rem;
  color: var(--text-light);
}

/* Grid Layout */
.grid {
  display: grid;
  gap: 2rem;
  grid-template-columns: repeat(auto-fit, minmax(300px, 1fr));
}

.grid-2 {
  grid-template-columns: repeat(auto-fit, minmax(400px, 1fr));
}

.grid-3 {
  grid-template-columns: repeat(auto-fit, minmax(300px, 1fr));
}

/* Card */
.card {
  background: var(--bg-white);
  border-radius: var(--radius-lg);
  padding: 2rem;
  box-shadow: var(--shadow-md);
  transition: transform 0.3s ease, box-shadow 0.3s ease;
  border: 1px solid var(--border-color);
}

.card:hover {
  transform: translateY(-5px);
  box-shadow: var(--shadow-xl);
}

.card-icon {
  width: 60px;
  height: 60px;
  background: linear-gradient(135deg, var(--primary-color), var(--secondary-color));
  border-radius: var(--radius-md);
  display: flex;
  align-items: center;
  justify-content: center;
  margin-bottom: 1.5rem;
  font-size: 1.75rem;
  color: white;
}

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

.card p {
  margin-bottom: 1.5rem;
  color: var(--text-light);
}

/* Button */
.button, .btn {
  display: inline-block;
  padding: 0.75rem 1.5rem;
  background: var(--primary-color);
  color: white;
  border-radius: var(--radius-md);
  font-weight: 600;
  text-align: center;
  transition: all 0.3s ease;
  border: none;
  cursor: pointer;
  text-decoration: none;
}

.button:hover, .btn:hover {
  background: var(--primary-dark);
  color: white;
  transform: translateY(-2px);
  box-shadow: var(--shadow-lg);
}

.button-secondary {
  background: var(--bg-light);
  color: var(--text-dark);
  border: 2px solid var(--border-color);
}

.button-secondary:hover {
  background: var(--bg-white);
  border-color: var(--primary-color);
  color: var(--primary-color);
}

.button-large {
  padding: 1rem 2rem;
  font-size: 1.125rem;
}

/* Background Sections */
.bg-light {
  background-color: var(--bg-light);
}

.bg-gradient {
  background: linear-gradient(135deg, var(--primary-color) 0%, var(--secondary-color) 100%);
  color: white;
}

.bg-gradient h2,
.bg-gradient h3,
.bg-gradient p {
  color: white;
}

/* Footer */
footer {
  background: var(--text-dark);
  color: white;
  padding: 3rem 2rem;
  text-align: center;
}

footer p {
  color: rgba(255, 255, 255, 0.8);
  margin-bottom: 0.5rem;
}

footer a {
  color: white;
  text-decoration: underline;
}

footer a:hover {
  color: var(--accent-color);
}

.copyright {
  display: flex;
  flex-wrap: wrap;
  justify-content: center;
  gap: 1rem;
  margin-top: 1rem;
  font-size: 0.875rem;
  color: rgba(255, 255, 255, 0.6);
}

/* Content Page Styles */
.content-page {
  max-width: 800px;
  margin: 0 auto;
  padding: 4rem 2rem;
}

.content-page h1 {
  margin-bottom: 2rem;
  text-align: center;
}

.content-page h2 {
  margin-top: 2rem;
  margin-bottom: 1rem;
}

.content-page h3 {
  margin-top: 1.5rem;
  margin-bottom: 0.75rem;
}

.content-page ul, .content-page ol {
  margin-left: 2rem;
  margin-bottom: 1rem;
}

.content-page li {
  margin-bottom: 0.5rem;
  color: var(--text-light);
}

.content-page strong {
  color: var(--text-dark);
  font-weight: 600;
}

/* App Features List */
.features-list {
  list-style: none;
  margin-left: 0;
}

.features-list li {
  padding-left: 2rem;
  position: relative;
  margin-bottom: 1rem;
}

.features-list li::before {
  content: "✓";
  position: absolute;
  left: 0;
  color: var(--success-color);
  font-weight: bold;
  font-size: 1.25rem;
}

/* Download Button Special */
.download-section {
  text-align: center;
  padding: 2rem;
  background: var(--bg-light);
  border-radius: var(--radius-lg);
  margin: 2rem 0;
}

/* Responsive Design */
@media (max-width: 768px) {
  .menu-toggle {
    display: block;
  }

  nav ul {
    display: none;
    position: absolute;
    top: 100%;
    left: 0;
    right: 0;
    background: var(--bg-white);
    flex-direction: column;
    padding: 1rem;
    box-shadow: var(--shadow-lg);
    gap: 0;
  }

  nav ul.active {
    display: flex;
  }

  nav li {
    width: 100%;
    padding: 0.75rem 0;
    border-bottom: 1px solid var(--border-color);
  }

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

  .hero h1 {
    font-size: 2rem;
  }

  .hero p {
    font-size: 1rem;
  }

  h1 { font-size: 2rem; }
  h2 { font-size: 1.75rem; }
  h3 { font-size: 1.25rem; }

  .grid,
  .grid-2,
  .grid-3 {
    grid-template-columns: 1fr;
  }

  section {
    padding: 3rem 1rem;
  }

  .container {
    padding: 0 1rem;
  }
}

/* Utility Classes */
.text-center { text-align: center; }
.text-left { text-align: left; }
.text-right { text-align: right; }

.mt-1 { margin-top: 0.5rem; }
.mt-2 { margin-top: 1rem; }
.mt-3 { margin-top: 1.5rem; }
.mt-4 { margin-top: 2rem; }

.mb-1 { margin-bottom: 0.5rem; }
.mb-2 { margin-bottom: 1rem; }
.mb-3 { margin-bottom: 1.5rem; }
.mb-4 { margin-bottom: 2rem; }

.p-1 { padding: 0.5rem; }
.p-2 { padding: 1rem; }
.p-3 { padding: 1.5rem; }
.p-4 { padding: 2rem; }

/* Animations */
@keyframes fadeIn {
  from {
    opacity: 0;
    transform: translateY(20px);
  }
  to {
    opacity: 1;
    transform: translateY(0);
  }
}

.fade-in {
  animation: fadeIn 0.6s ease-out;
}

/* Print Styles */
@media print {
  header, footer, .button, .btn {
    display: none;
  }
  
  body {
    color: black;
    background: white;
  }
}