/* ============================================
   MobiFit Marketing Website - Main Stylesheet
   Modern Minimalist Design
   ============================================ */

/* CSS Variables - Design System */
:root {
  /* Colors */
  --color-primary-bg: #000000;
  --color-secondary-bg: #1a1a1a;
  --color-white: #FFFFFF;
  --color-accent: #FF6B35;
  --color-accent-hover: #FF8C42;
  --color-text-primary: #000000;
  --color-text-secondary: #6B7280;
  --color-text-light: #FFFFFF;
  --color-border: #E5E7EB;
  --color-gray-light: #F9FAFB;
  --color-gray-medium: #E5E7EB;
  
  /* Typography */
  --font-heading: 'Inter', -apple-system, BlinkMacSystemFont, 'Segoe UI', sans-serif;
  --font-body: 'Inter', -apple-system, BlinkMacSystemFont, 'Segoe UI', sans-serif;
  
  /* Spacing */
  --spacing-xs: 0.5rem;
  --spacing-sm: 1rem;
  --spacing-md: 2rem;
  --spacing-lg: 4rem;
  --spacing-xl: 6rem;
  
  /* Layout */
  --container-max-width: 1200px;
  --border-radius: 8px;
  --transition: all 0.3s ease;
}

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

html {
  scroll-behavior: smooth;
}

body {
  font-family: var(--font-body);
  font-size: 16px;
  line-height: 1.6;
  color: var(--color-text-primary);
  background-color: var(--color-white);
  -webkit-font-smoothing: antialiased;
  -moz-osx-font-smoothing: grayscale;
}

/* Typography */
h1, h2, h3, h4, h5, h6 {
  font-family: var(--font-heading);
  font-weight: 700;
  line-height: 1.2;
  margin-bottom: var(--spacing-sm);
}

h1 {
  font-size: 3.5rem;
  font-weight: 800;
}

h2 {
  font-size: 2.5rem;
}

h3 {
  font-size: 1.75rem;
}

h4 {
  font-size: 1.5rem;
}

p {
  margin-bottom: var(--spacing-sm);
  color: var(--color-text-secondary);
}

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

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

/* Container */
.container {
  max-width: var(--container-max-width);
  margin: 0 auto;
  padding: 0 var(--spacing-md);
}

/* Buttons */
.btn {
  display: inline-block;
  padding: 1rem 2rem;
  font-size: 1rem;
  font-weight: 600;
  text-align: center;
  border: none;
  border-radius: var(--border-radius);
  cursor: pointer;
  transition: var(--transition);
  text-transform: uppercase;
  letter-spacing: 0.5px;
}

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

.btn-primary:hover {
  background-color: var(--color-accent-hover);
  transform: translateY(-2px);
  box-shadow: 0 10px 25px rgba(255, 107, 53, 0.3);
}

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

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

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

.btn-white:hover {
  background-color: var(--color-gray-light);
}

.btn-large {
  padding: 1.25rem 2.5rem;
  font-size: 1.125rem;
}

/* Navigation */
.navbar {
  position: fixed;
  top: 0;
  left: 0;
  right: 0;
  background-color: var(--color-white);
  border-bottom: 1px solid var(--color-border);
  z-index: 1000;
  transition: var(--transition);
}

.navbar.scrolled {
  box-shadow: 0 2px 10px rgba(0, 0, 0, 0.1);
}

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

.logo {
  font-size: 1.5rem;
  font-weight: 800;
  color: var(--color-primary-bg);
}

.logo span {
  color: var(--color-accent);
}

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

.nav-menu a {
  font-weight: 500;
  color: var(--color-text-primary);
  padding: 0.5rem 0;
}

.nav-menu a:hover,
.nav-menu a.active {
  color: var(--color-accent);
}

.mobile-menu-toggle {
  display: none;
  background: none;
  border: none;
  font-size: 1.5rem;
  cursor: pointer;
  color: var(--color-text-primary);
}

/* Hero Section */
.hero {
  min-height: 100vh;
  display: flex;
  align-items: center;
  justify-content: center;
  background: linear-gradient(135deg, var(--color-primary-bg) 0%, var(--color-secondary-bg) 100%);
  color: var(--color-text-light);
  text-align: center;
  padding: var(--spacing-xl) var(--spacing-md);
  margin-top: 70px;
}

.hero-content h1 {
  font-size: 4rem;
  margin-bottom: var(--spacing-md);
  color: var(--color-white);
}

.hero-content h1 .accent {
  color: var(--color-accent);
}

.hero-content p {
  font-size: 1.25rem;
  color: rgba(255, 255, 255, 0.8);
  margin-bottom: var(--spacing-lg);
  max-width: 600px;
  margin-left: auto;
  margin-right: auto;
}

/* Sections */
.section {
  padding: var(--spacing-xl) 0;
}

.section-title {
  text-align: center;
  margin-bottom: var(--spacing-lg);
}

.section-title h2 {
  font-size: 2.5rem;
  margin-bottom: var(--spacing-sm);
}

.section-title p {
  font-size: 1.125rem;
  color: var(--color-text-secondary);
  max-width: 600px;
  margin: 0 auto;
}

/* Features Grid */
.features-grid {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(300px, 1fr));
  gap: var(--spacing-md);
  margin-top: var(--spacing-lg);
}

.feature-card {
  background: var(--color-white);
  border: 1px solid var(--color-border);
  border-radius: var(--border-radius);
  padding: var(--spacing-md);
  text-align: center;
  transition: var(--transition);
}

.feature-card:hover {
  transform: translateY(-5px);
  box-shadow: 0 10px 30px rgba(0, 0, 0, 0.1);
  border-color: var(--color-accent);
}

.feature-icon {
  width: 60px;
  height: 60px;
  margin: 0 auto var(--spacing-sm);
  background-color: rgba(255, 107, 53, 0.1);
  border-radius: 50%;
  display: flex;
  align-items: center;
  justify-content: center;
  color: var(--color-accent);
  font-size: 1.5rem;
}

.feature-card h3 {
  margin-bottom: var(--spacing-xs);
  color: var(--color-text-primary);
}

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

/* Pricing Cards */
.pricing-grid {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(300px, 1fr));
  gap: var(--spacing-md);
  margin-top: var(--spacing-lg);
}

.pricing-card {
  background: var(--color-white);
  border: 2px solid var(--color-border);
  border-radius: var(--border-radius);
  padding: var(--spacing-md);
  text-align: center;
  transition: var(--transition);
  position: relative;
}

.pricing-card.featured {
  border-color: var(--color-accent);
  transform: scale(1.05);
}

.pricing-card:hover {
  box-shadow: 0 10px 30px rgba(0, 0, 0, 0.1);
}

.pricing-card h3 {
  margin-bottom: var(--spacing-sm);
}

.pricing-price {
  font-size: 3rem;
  font-weight: 800;
  color: var(--color-text-primary);
  margin: var(--spacing-sm) 0;
}

.pricing-price span {
  font-size: 1rem;
  color: var(--color-text-secondary);
  font-weight: 400;
}

.pricing-features {
  list-style: none;
  margin: var(--spacing-md) 0;
  text-align: left;
}

.pricing-features li {
  padding: var(--spacing-xs) 0;
  color: var(--color-text-secondary);
}

.pricing-features li:before {
  content: "✓ ";
  color: var(--color-accent);
  font-weight: bold;
  margin-right: var(--spacing-xs);
}

/* Forms */
.form-group {
  margin-bottom: var(--spacing-md);
}

.form-group label {
  display: block;
  margin-bottom: var(--spacing-xs);
  font-weight: 500;
  color: var(--color-text-primary);
}

.form-group input,
.form-group textarea,
.form-group select {
  width: 100%;
  padding: 0.75rem;
  border: 1px solid var(--color-border);
  border-radius: var(--border-radius);
  font-size: 1rem;
  font-family: var(--font-body);
  transition: var(--transition);
}

.form-group input:focus,
.form-group textarea:focus,
.form-group select:focus {
  outline: none;
  border-color: var(--color-accent);
  box-shadow: 0 0 0 3px rgba(255, 107, 53, 0.1);
}

.form-group textarea {
  resize: vertical;
  min-height: 120px;
}

/* Footer */
.footer {
  background-color: var(--color-primary-bg);
  color: var(--color-text-light);
  padding: var(--spacing-lg) 0;
  margin-top: var(--spacing-xl);
}

.footer-content {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(250px, 1fr));
  gap: var(--spacing-md);
  margin-bottom: var(--spacing-md);
}

.footer-section h4 {
  color: var(--color-white);
  margin-bottom: var(--spacing-sm);
}

.footer-section a {
  color: rgba(255, 255, 255, 0.7);
  display: block;
  margin-bottom: var(--spacing-xs);
}

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

.footer-bottom {
  text-align: center;
  padding-top: var(--spacing-md);
  border-top: 1px solid rgba(255, 255, 255, 0.1);
  color: rgba(255, 255, 255, 0.7);
}

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

.text-accent {
  color: var(--color-accent);
}

.bg-dark {
  background-color: var(--color-primary-bg);
  color: var(--color-text-light);
}

.bg-light {
  background-color: var(--color-gray-light);
}

.mt-1 { margin-top: var(--spacing-sm); }
.mt-2 { margin-top: var(--spacing-md); }
.mt-3 { margin-top: var(--spacing-lg); }
.mb-1 { margin-bottom: var(--spacing-sm); }
.mb-2 { margin-bottom: var(--spacing-md); }
.mb-3 { margin-bottom: var(--spacing-lg); }

/* Responsive Design */
@media (max-width: 768px) {
  h1 {
    font-size: 2.5rem;
  }
  
  h2 {
    font-size: 2rem;
  }
  
  .hero-content h1 {
    font-size: 2.5rem;
  }
  
  .nav-menu {
    position: fixed;
    top: 70px;
    left: -100%;
    width: 100%;
    height: calc(100vh - 70px);
    background-color: var(--color-white);
    flex-direction: column;
    padding: var(--spacing-md);
    transition: left 0.3s ease;
    box-shadow: 2px 0 10px rgba(0, 0, 0, 0.1);
  }
  
  .nav-menu.active {
    left: 0;
  }
  
  .mobile-menu-toggle {
    display: block;
  }
  
  .pricing-card.featured {
    transform: scale(1);
  }
  
  .features-grid,
  .pricing-grid {
    grid-template-columns: 1fr;
  }
}

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