.container {
  max-width: 900px;
  margin: auto;
  padding: 40px 20px;
}

.section {
  margin-top: 40px;
  animation: fadeIn 0.6s ease-in;
}

.hero {
  text-align: center;
  margin-bottom: 40px;
}
.intro {
  text-align: left;
  margin-bottom: 40px;
}

.footer {
  margin-top: 60px;
  text-align: center;
  font-size: 0.9rem;
  color: #6b7280;
}

/* header / nav */
.site-header {
  position: sticky;
  top: 0;
  background: rgba(249, 250, 251, 0.95);
  backdrop-filter: blur(6px);
  border-bottom: 1px solid #e5e7eb;
  z-index: 1000;
}

.nav {
  max-width: 900px;
  margin: auto;
  padding: 12px 20px;
  display: flex;
  justify-content: space-between;
  align-items: center;
}

.brand {
  font-weight: 600;
  font-size: 1rem;
  color: #111827;
}

.nav-right a {
  margin-left: 20px;
  font-size: 0.9rem;
  color: #374151;
}

.nav-right a:hover {
  color: #2563eb;
}

.nav-dropdown {
  position: relative;
  display: inline-block;
  margin-left: 20px;
}

.dropdown-trigger {
  font-size: 0.9rem;
  color: #374151;
  cursor: pointer;
}

.dropdown-menu {
  position: absolute;
  top: 140%;
  right: 0;
  background: #ffffff;
  border: 1px solid #e5e7eb;
  border-radius: 8px;
  box-shadow: 0 10px 25px rgba(0,0,0,0.08);
  min-width: 180px;
  display: none;
  z-index: 2000;
}

.dropdown-menu a {
  display: block;
  padding: 10px 14px;
  font-size: 0.9rem;
  color: #374151;
}

.dropdown-menu a:hover {
  background: #f3f4f6;
}

.nav-dropdown:hover .dropdown-menu {
  display: block;
}