*, *::before, *::after { box-sizing: border-box; margin: 0; padding: 0; }
:root {
  --primary: #4CAF50; --primary-dark: #388E3C; --primary-light: #C8E6C9;
  --text: #333; --text-light: #666; --text-muted: #999;
  --bg: #fff; --bg-alt: #F8F9FA; --border: #E0E0E0;
  --shadow: 0 2px 12px rgba(0,0,0,0.08); --radius: 10px; --transition: 0.3s ease;
}
html { scroll-behavior: smooth; }
body { font-family: -apple-system, BlinkMacSystemFont, 'Segoe UI', Roboto, Arial, sans-serif; color: var(--text); line-height: 1.6; }
a { color: var(--primary); text-decoration: none; }
a:hover { color: var(--primary-dark); }
.container { max-width: 900px; margin: 0 auto; padding: 0 20px; }

/* Nav */
.nav { position: sticky; top: 0; z-index: 100; background: rgba(255,255,255,0.95); backdrop-filter: blur(8px); border-bottom: 1px solid var(--border); }
.nav .container { display: flex; align-items: center; justify-content: space-between; height: 56px; }
.nav-brand { display: flex; align-items: center; gap: 8px; font-size: 1.2rem; font-weight: 700; color: var(--primary-dark); }
.nav-logo { width: 32px; height: 32px; border-radius: 8px; }
.nav-links { display: flex; gap: 20px; list-style: none; }
.nav-links a { color: var(--text-light); font-size: 0.9rem; font-weight: 500; }
.nav-links a:hover { color: var(--primary-dark); }
.menu-btn { display: none; background: none; border: none; font-size: 1.3rem; cursor: pointer; }

/* Language Selector */
.lang-selector { 
  display: flex; 
  gap: 4px;
  align-items: center; 
  margin-left: 16px;
}
.lang-btn { 
  padding: 5px 10px; 
  border: 1px solid var(--border); 
  background: var(--bg); 
  color: var(--text-light); 
  border-radius: 6px; 
  font-size: 0.8rem; 
  font-weight: 500; 
  cursor: pointer; 
  transition: all var(--transition); 
}
.lang-btn:hover { 
  border-color: var(--primary); 
  color: var(--primary); 
}
.lang-btn.active { 
  background: var(--primary); 
  color: white; 
  border-color: var(--primary); 
}

/* Hero */
.hero { padding: 60px 0 40px; text-align: center; background: linear-gradient(135deg, #E8F5E9, #FFF8E1); }
.hero h1 { font-size: 2rem; font-weight: 800; margin-bottom: 12px; }
.hero h1 span { color: var(--primary); }
.hero p { font-size: 1.05rem; color: var(--text-light); max-width: 520px; margin: 0 auto 24px; }

/* Features */
.features { display: grid; grid-template-columns: repeat(3, 1fr); gap: 20px; padding: 40px 0; }
.feat { text-align: center; padding: 24px 16px; background: var(--bg); border-radius: var(--radius); box-shadow: var(--shadow); }
.feat .icon { font-size: 1.6rem; margin-bottom: 10px; }
.feat h3 { font-size: 1rem; margin-bottom: 6px; }
.feat p { font-size: 0.85rem; color: var(--text-light); }

/* Section */
.section { padding: 48px 0; }
.section-alt { background: var(--bg-alt); }
.section h2 { font-size: 1.5rem; font-weight: 700; margin-bottom: 16px; color: var(--primary-dark); }
.section h3 { font-size: 1.1rem; font-weight: 600; margin-top: 20px; margin-bottom: 8px; }
.section p, .section li { font-size: 0.95rem; color: var(--text-light); line-height: 1.7; margin-bottom: 8px; }
.section ul { padding-left: 20px; margin-bottom: 12px; }
.section li { margin-bottom: 4px; }
.divider { border: none; border-top: 1px solid var(--border); margin: 32px 0; }

/* Footer */
.footer { background: #1A1A2E; color: #aaa; padding: 24px 0; text-align: center; font-size: 0.85rem; }
.footer a { color: #ccc; }
.footer a:hover { color: #fff; }
.footer-links { display: flex; justify-content: center; gap: 24px; margin-bottom: 12px; flex-wrap: wrap; }
.footer-links a { color: #ccc; font-size: 0.85rem; }

/* Responsive */
@media (max-width: 640px) {
  .nav-links { display: none; }
  .nav-links.open { 
    display: flex; 
    flex-direction: column; 
    position: absolute; 
    top: 56px; 
    left: 0; 
    right: 0; 
    background: #fff; 
    padding: 12px 20px; 
    gap: 8px; 
    box-shadow: var(--shadow);
    z-index: 99;
  }
  .menu-btn { display: block; }
  .lang-selector { margin-left: auto; margin-right: 10px; }
  .hero h1 { font-size: 1.5rem; }
  .features { grid-template-columns: 1fr; }
}