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

/* Variables */
:root {
  --primary-color: #007AFF;
  --secondary-color: #5856D6;
  --accent-color: #FF3B30;
  --text-primary: #1D1D1F;
  --text-secondary: #6E6E73;
  --background: #FFFFFF;
  --background-alt: #F5F5F7;
  --border-color: #D2D2D7;
  --shadow: 0 4px 20px rgba(0, 0, 0, 0.08);
  --shadow-large: 0 12px 40px rgba(0, 0, 0, 0.12);
  --border-radius: 16px;
  --transition: all 0.3s cubic-bezier(0.4, 0, 0.2, 1);
  --max-width: 1200px;
}

@media (prefers-color-scheme: dark) {
  :root {
    --text-primary: #F5F5F7;
    --text-secondary: #A1A1A6;
    --background: #000000;
    --background-alt: #1D1D1F;
    --border-color: #424245;
  }
}

/* Base */
html {
  scroll-behavior: smooth;
}

body {
  font-family: -apple-system, BlinkMacSystemFont, "SF Pro Display", "Segoe UI", Roboto, Helvetica, Arial, sans-serif;
  background: var(--background);
  color: var(--text-primary);
  line-height: 1.6;
  -webkit-font-smoothing: antialiased;
  -moz-osx-font-smoothing: grayscale;
}

/* Navigation */
.nav {
  position: sticky;
  top: 0;
  background: rgba(255, 255, 255, 0.8);
  backdrop-filter: blur(20px);
  -webkit-backdrop-filter: blur(20px);
  border-bottom: 1px solid var(--border-color);
  z-index: 1000;
  padding: 16px 0;
}

@media (prefers-color-scheme: dark) {
  .nav {
    background: rgba(0, 0, 0, 0.8);
  }
}

.nav-container {
  max-width: var(--max-width);
  margin: 0 auto;
  padding: 0 24px;
  display: flex;
  justify-content: space-between;
  align-items: center;
}

.nav-brand {
  display: flex;
  align-items: center;
  gap: 12px;
}

.nav-logo {
  width: 40px;
  height: 40px;
  border-radius: 10px;
}

.nav-title {
  font-size: 1.25rem;
  font-weight: 600;
  color: var(--text-primary);
}

.nav-links {
  display: flex;
  gap: 32px;
  align-items: center;
}

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

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

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

/* Hero Section */
.hero {
  padding: 100px 24px 120px;
  background: linear-gradient(180deg, var(--background) 0%, var(--background-alt) 100%);
  text-align: center;
}

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

.hero-badge {
  display: inline-block;
  padding: 8px 16px;
  background: var(--background);
  border: 1px solid var(--border-color);
  border-radius: 20px;
  font-size: 0.875rem;
  font-weight: 500;
  color: var(--text-secondary);
  margin-bottom: 24px;
}

.hero-title {
  font-size: 3.5rem;
  font-weight: 700;
  line-height: 1.1;
  margin-bottom: 24px;
  letter-spacing: -0.02em;
}

.hero-subtitle {
  font-size: 1.25rem;
  color: var(--text-secondary);
  margin-bottom: 40px;
  line-height: 1.5;
}

.hero-cta {
  display: flex;
  gap: 16px;
  justify-content: center;
  margin-bottom: 16px;
}

.hero-note {
  font-size: 0.875rem;
  color: var(--text-secondary);
}

/* Buttons */
.button {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  gap: 8px;
  padding: 12px 24px;
  border-radius: 12px;
  font-size: 1rem;
  font-weight: 600;
  text-decoration: none;
  border: none;
  cursor: pointer;
  transition: var(--transition);
  white-space: nowrap;
}

.button:active {
  transform: scale(0.98);
}

.button-large {
  padding: 16px 32px;
  font-size: 1.125rem;
}

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

.button-primary:hover {
  background: #0051D5;
  box-shadow: 0 8px 24px rgba(0, 122, 255, 0.3);
}

.button-secondary {
  background: var(--background);
  color: var(--text-primary);
  border: 1px solid var(--border-color);
}

.button-secondary:hover {
  background: var(--background-alt);
}

.button-icon {
  width: 20px;
  height: 20px;
}

/* Container */
.container {
  max-width: var(--max-width);
  margin: 0 auto;
  padding: 0 24px;
}

/* Section Title */
.section-title {
  font-size: 2.5rem;
  font-weight: 700;
  text-align: center;
  margin-bottom: 60px;
  letter-spacing: -0.02em;
}

/* Features Section */
.features {
  padding: 100px 24px;
}

.features-grid {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(300px, 1fr));
  gap: 32px;
}

.feature-card {
  padding: 32px;
  background: var(--background);
  border: 1px solid var(--border-color);
  border-radius: var(--border-radius);
  transition: var(--transition);
}

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

.feature-icon {
  font-size: 3rem;
  margin-bottom: 16px;
}

.feature-title {
  font-size: 1.5rem;
  font-weight: 600;
  margin-bottom: 12px;
}

.feature-description {
  color: var(--text-secondary);
  line-height: 1.6;
}

/* How It Works Section */
.how-it-works {
  padding: 100px 24px;
  background: var(--background-alt);
}

.steps {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(280px, 1fr));
  gap: 48px;
  max-width: 1000px;
  margin: 0 auto;
}

.step {
  text-align: center;
}

.step-number {
  width: 60px;
  height: 60px;
  background: var(--primary-color);
  color: white;
  border-radius: 50%;
  display: flex;
  align-items: center;
  justify-content: center;
  font-size: 1.5rem;
  font-weight: 700;
  margin: 0 auto 20px;
}

.step-title {
  font-size: 1.5rem;
  font-weight: 600;
  margin-bottom: 12px;
}

.step-description {
  color: var(--text-secondary);
  line-height: 1.6;
}

/* CTA Section */
.cta-section {
  padding: 100px 24px;
  text-align: center;
  background: linear-gradient(135deg, var(--primary-color) 0%, var(--secondary-color) 100%);
  color: white;
}

.cta-title {
  font-size: 2.5rem;
  font-weight: 700;
  margin-bottom: 16px;
  letter-spacing: -0.02em;
}

.cta-subtitle {
  font-size: 1.25rem;
  margin-bottom: 40px;
  opacity: 0.9;
}

.cta-section .button-primary {
  background: white;
  color: var(--primary-color);
}

.cta-section .button-primary:hover {
  background: var(--background-alt);
  box-shadow: 0 8px 24px rgba(0, 0, 0, 0.2);
}

/* Footer */
.footer {
  padding: 60px 24px 32px;
  background: var(--background-alt);
  border-top: 1px solid var(--border-color);
}

.footer-container {
  max-width: var(--max-width);
  margin: 0 auto;
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(200px, 1fr));
  gap: 48px;
  margin-bottom: 48px;
}

.footer-section {
}

.footer-title {
  font-size: 1rem;
  font-weight: 600;
  margin-bottom: 16px;
}

.footer-text {
  color: var(--text-secondary);
  line-height: 1.6;
}

.footer-links {
  list-style: none;
  display: flex;
  flex-direction: column;
  gap: 8px;
}

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

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

.footer-bottom {
  max-width: var(--max-width);
  margin: 0 auto;
  padding-top: 32px;
  border-top: 1px solid var(--border-color);
  text-align: center;
  color: var(--text-secondary);
  font-size: 0.875rem;
}

/* Modal */
.modal {
  position: fixed;
  top: 0;
  left: 0;
  width: 100%;
  height: 100%;
  z-index: 2000;
  display: flex;
  align-items: center;
  justify-content: center;
}

.modal-overlay {
  position: absolute;
  top: 0;
  left: 0;
  width: 100%;
  height: 100%;
  background: rgba(0, 0, 0, 0.8);
  backdrop-filter: blur(10px);
  -webkit-backdrop-filter: blur(10px);
}

.modal-content {
  position: relative;
  width: 90%;
  max-width: 1200px;
  aspect-ratio: 16 / 9;
  background: var(--background);
  border-radius: var(--border-radius);
  overflow: hidden;
  box-shadow: var(--shadow-large);
}

.modal-close {
  position: absolute;
  top: 16px;
  right: 16px;
  width: 40px;
  height: 40px;
  background: rgba(0, 0, 0, 0.5);
  color: white;
  border: none;
  border-radius: 50%;
  font-size: 24px;
  cursor: pointer;
  z-index: 1;
  transition: var(--transition);
}

.modal-close:hover {
  background: rgba(0, 0, 0, 0.7);
}

.video-container {
  width: 100%;
  height: 100%;
}

/* Responsive */
@media (max-width: 768px) {
  .hero-title {
    font-size: 2.5rem;
  }

  .hero-subtitle {
    font-size: 1.125rem;
  }

  .hero-cta {
    flex-direction: column;
  }

  .section-title {
    font-size: 2rem;
  }

  .nav-links {
    display: none;
  }

  .features-grid {
    grid-template-columns: 1fr;
  }

  .steps {
    grid-template-columns: 1fr;
    gap: 32px;
  }

  .footer-container {
    grid-template-columns: 1fr;
    gap: 32px;
  }
}

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

.hero,
.features,
.how-it-works,
.cta-section {
  animation: fadeIn 0.8s ease;
}