:root {
  --primary: #0EA5E9;
  --primary-hover: #0284C7;
  --bg-color: #FFFFFF;
  --surface-color: #F8FAFC;
  --text-main: #0F172A;
  --text-muted: #64748B;
  --shadow-sm: 0 4px 6px -1px rgba(0, 0, 0, 0.05);
  --shadow-lg: 0 20px 25px -5px rgba(0, 0, 0, 0.05);
  --transition: all 0.3s ease;
  --font-family: 'Inter', -apple-system, BlinkMacSystemFont, 'Segoe UI', Roboto, sans-serif;
}

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

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

/* Header */
.header {
  display: flex;
  justify-content: space-between;
  align-items: center;
  padding: 1.5rem 5%;
  position: sticky;
  top: 0;
  background: rgba(255, 255, 255, 0.9);
  backdrop-filter: blur(10px);
  z-index: 100;
  border-bottom: 1px solid rgba(0,0,0,0.05);
}

.logo {
  display: flex;
  align-items: center;
  gap: 0.75rem;
  font-weight: 700;
  font-size: 1.5rem;
  color: var(--text-main);
  text-decoration: none;
}

.logo img {
  height: 50px;
}

.btn {
  display: inline-block;
  padding: 0.75rem 1.5rem;
  border-radius: 999px;
  font-weight: 600;
  text-decoration: none;
  transition: var(--transition);
  cursor: pointer;
}

.btn-primary {
  background-color: var(--primary);
  color: white;
  box-shadow: 0 4px 14px 0 rgba(14, 165, 233, 0.39);
}

.btn-primary:hover {
  background-color: var(--primary-hover);
  transform: translateY(-2px);
  box-shadow: 0 6px 20px rgba(14, 165, 233, 0.4);
}

/* Hero Section */
.hero {
  padding: 8rem 5% 4rem;
  text-align: center;
  background: linear-gradient(135deg, #F0F9FF 0%, #E0F2FE 100%);
  position: relative;
  overflow: hidden;
}

.hero h1 {
  font-size: 4rem;
  font-weight: 800;
  line-height: 1.1;
  margin-bottom: 1.5rem;
  letter-spacing: -0.02em;
}

.hero p {
  font-size: 1.25rem;
  color: var(--text-muted);
  max-width: 600px;
  margin: 0 auto 2.5rem;
}

.hero-actions {
  display: flex;
  gap: 1rem;
  justify-content: center;
}

/* Features */
.features {
  padding: 6rem 5%;
  background-color: var(--bg-color);
}

.feature-row {
  display: flex;
  align-items: center;
  justify-content: space-between;
  margin-bottom: 8rem;
  gap: 4rem;
}

.feature-row:nth-child(even) {
  flex-direction: row-reverse;
}

.feature-content {
  flex: 1;
}

.feature-content h2 {
  font-size: 2.5rem;
  margin-bottom: 1rem;
  font-weight: 700;
}

.feature-content p {
  font-size: 1.125rem;
  color: var(--text-muted);
  margin-bottom: 1.5rem;
}

.feature-list {
  list-style: none;
}

.feature-list li {
  margin-bottom: 0.75rem;
  display: flex;
  align-items: center;
  gap: 0.5rem;
  font-weight: 500;
}

.feature-list li::before {
  content: '✓';
  color: var(--primary);
  font-weight: bold;
}

.feature-image {
  flex: 1;
  display: flex;
  justify-content: center;
  position: relative;
}

.feature-image img {
  max-width: 320px;
  border-radius: 40px;
  box-shadow: var(--shadow-lg);
  transition: transform 0.5s ease;
  border: 8px solid white;
}

.feature-image:hover img {
  transform: translateY(-10px) scale(1.02);
}

/* Download Page */
.download-page {
  display: flex;
  flex-direction: column;
  align-items: center;
  justify-content: center;
  min-height: calc(100vh - 80px);
  background: var(--surface-color);
  text-align: center;
  padding: 2rem;
}

.download-page h1 {
  font-size: 3rem;
  margin-bottom: 1rem;
}

.download-page p {
  color: var(--text-muted);
  font-size: 1.25rem;
  margin-bottom: 3rem;
}

.store-links {
  display: flex;
  gap: 2rem;
  justify-content: center;
  flex-wrap: wrap;
}

.store-btn {
  background: white;
  padding: 1rem 2rem;
  border-radius: 16px;
  display: flex;
  align-items: center;
  gap: 1rem;
  text-decoration: none;
  color: var(--text-main);
  box-shadow: var(--shadow-sm);
  transition: var(--transition);
  font-weight: 600;
  border: 1px solid rgba(0,0,0,0.05);
}

.store-btn:hover {
  transform: translateY(-5px);
  box-shadow: var(--shadow-lg);
  border-color: var(--primary);
}

.store-btn img {
  height: 32px;
}

/* Footer */
footer {
  text-align: center;
  padding: 2rem;
  color: var(--text-muted);
  border-top: 1px solid rgba(0,0,0,0.05);
}

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

.animate-up {
  animation: fadeUp 0.8s cubic-bezier(0.16, 1, 0.3, 1) forwards;
}

/* Responsive */
@media (max-width: 768px) {
  .feature-row, .feature-row:nth-child(even) {
    flex-direction: column;
    text-align: center;
    gap: 2rem;
  }
  
  .feature-list li {
    justify-content: center;
  }
  
  .hero h1 {
    font-size: 2.5rem;
  }
}