/* Mobile-first base styles (320px+) */
* { box-sizing: border-box; }
body {
  margin: 0;
  font-family: -apple-system, BlinkMacSystemFont, "Segoe UI", Roboto, sans-serif;
  font-size: 1rem;
  line-height: 1.5;
  color: #1a1a1a;
  background: #ffffff;
  overflow-x: hidden;
}
img { max-width: 100%; height: auto; }

a { color: #1d4ed8; }

.site-header {
  padding: 0.75rem 1rem;
  border-bottom: 1px solid #e5e5e5;
}
.site-nav {
  display: flex;
  flex-direction: column;
  gap: 0.75rem;
  max-width: 75ch;
  margin: 0 auto;
}
.brand {
  font-weight: 700;
  text-decoration: none;
  font-size: 1.125rem;
  color: #1a1a1a;
}
.nav-links {
  list-style: none;
  display: flex;
  flex-wrap: wrap;
  gap: 0.5rem 1rem;
  padding: 0;
  margin: 0;
}
.nav-links a {
  display: inline-flex;
  align-items: center;
  min-height: 44px;
  padding: 0.25rem 0.5rem;
  text-decoration: none;
  color: #1a1a1a;
}
.nav-links a.active,
.nav-links a[aria-current="page"] {
  font-weight: 700;
  border-bottom: 2px solid #1d4ed8;
}

main {
  max-width: 75ch;
  margin: 0 auto;
  padding: 1rem;
  width: 100%;
}

.hero {
  text-align: center;
  padding: 2rem 1rem;
}
.hero h1 {
  font-size: 1.75rem;
  margin-bottom: 0.75rem;
}
.hero p {
  font-size: 1rem;
  margin-bottom: 1.5rem;
}

.btn {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  min-height: 48px;
  min-width: 44px;
  padding: 0.75rem 1.5rem;
  border-radius: 6px;
  text-decoration: none;
  font-size: 1rem;
  border: 2px solid transparent;
  cursor: pointer;
}
.btn-primary {
  background: #1d4ed8;
  color: #ffffff;
}
.btn-secondary {
  background: transparent;
  border-color: #1d4ed8;
  color: #1d4ed8;
}

.features {
  display: flex;
  flex-direction: column;
  gap: 1rem;
  padding: 1rem 0;
}
.feature-card {
  border: 1px solid #e5e5e5;
  border-radius: 8px;
  padding: 1.25rem;
}
.feature-card h2 {
  font-size: 1.125rem;
  margin-top: 0;
}

.page-header {
  padding: 1.5rem 0;
}
.content-section {
  padding: 0.75rem 0;
}

.pricing-tiers {
  display: flex;
  flex-direction: column;
  gap: 1rem;
  padding: 1rem 0;
}
.pricing-card {
  border: 1px solid #e5e5e5;
  border-radius: 8px;
  padding: 1.5rem;
  text-align: center;
}
.pricing-card-featured {
  border-color: #1d4ed8;
  border-width: 2px;
}
.tier-price {
  font-size: 1.75rem;
  font-weight: 700;
}
.tier-price span {
  font-size: 0.875rem;
  font-weight: 400;
}
.tier-features {
  list-style: none;
  padding: 0;
  text-align: left;
  margin: 1rem 0;
}
.tier-features li {
  padding: 0.4rem 0;
  border-bottom: 1px solid #f0f0f0;
}

.contact-section form {
  display: flex;
  flex-direction: column;
  gap: 1rem;
  padding: 1rem 0;
}
.form-group {
  display: flex;
  flex-direction: column;
  gap: 0.375rem;
}
.form-group label {
  font-weight: 600;
}
.form-group input,
.form-group textarea {
  min-height: 48px;
  padding: 0.6rem 0.75rem;
  font-size: 1rem;
  border: 1px solid #cfcfcf;
  border-radius: 6px;
  font-family: inherit;
}
.form-group textarea { min-height: 120px; }
.error-message {
  color: #b91c1c;
  font-size: 0.875rem;
  min-height: 1.2em;
}
.form-success {
  color: #15803d;
  font-weight: 600;
}

.site-footer {
  text-align: center;
  padding: 1.5rem 1rem;
  border-top: 1px solid #e5e5e5;
  font-size: 0.875rem;
  color: #4b4b4b;
}

/* Tablet and up */
@media (min-width: 600px) {
  .site-nav {
    flex-direction: row;
    justify-content: space-between;
    align-items: center;
  }
  .nav-links { flex-direction: row; }
  .features {
    flex-direction: row;
  }
  .feature-card { flex: 1; }
}

/* Desktop and up */
@media (min-width: 900px) {
  main { max-width: 75ch; }
  .pricing-tiers {
    flex-direction: row;
    align-items: stretch;
  }
  .pricing-card { flex: 1; }
  .hero h1 { font-size: 2.25rem; }
}