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

body {
  font-family: -apple-system, BlinkMacSystemFont, "Segoe UI", Roboto, Helvetica, Arial, sans-serif;
  background: #fff;
  color: #111;
  -webkit-font-smoothing: antialiased;
}

/* ---- Nav ---- */
header {
  position: fixed;
  top: 0;
  left: 0;
  width: 100%;
  z-index: 100;
  background: rgba(255, 255, 255, 0.95);
  backdrop-filter: blur(8px);
  -webkit-backdrop-filter: blur(8px);
  border-bottom: 1px solid rgba(0, 0, 0, 0.06);
}

.nav-inner {
  max-width: 960px;
  margin: 0 auto;
  padding: 0 24px;
  height: 56px;
  display: flex;
  align-items: center;
  justify-content: space-between;
}

.nav-logo {
  font-size: 0.9375rem;
  font-weight: 600;
  color: #111;
  text-decoration: none;
  letter-spacing: -0.01em;
}

.nav-links {
  display: flex;
  gap: 28px;
  list-style: none;
}

.nav-links a {
  font-size: 0.8125rem;
  color: #666;
  text-decoration: none;
  transition: color 0.2s;
}

.nav-links a:hover,
.nav-links a.active {
  color: #111;
}

.nav-toggle {
  display: none;
  background: none;
  border: none;
  font-size: 1.25rem;
  color: #111;
  cursor: pointer;
  padding: 4px;
}

/* ---- Footer ---- */
footer {
  background: #fafafa;
  border-top: 1px solid rgba(0, 0, 0, 0.06);
  padding: 48px 24px;
}

.footer-inner {
  max-width: 960px;
  margin: 0 auto;
  display: flex;
  justify-content: space-between;
  align-items: flex-start;
  gap: 32px;
}

.footer-brand {
  font-size: 0.875rem;
  font-weight: 600;
  color: #111;
  margin-bottom: 6px;
}

.footer-copy {
  font-size: 0.75rem;
  color: #999;
  margin-bottom: 4px;
}

.footer-email a {
  font-size: 0.75rem;
  color: #888;
  text-decoration: none;
  transition: color 0.2s;
}

.footer-email a:hover {
  color: #111;
}

.footer-links {
  list-style: none;
  display: flex;
  flex-wrap: wrap;
  gap: 20px;
}

.footer-links a {
  font-size: 0.75rem;
  color: #888;
  text-decoration: none;
  transition: color 0.2s;
}

.footer-links a:hover {
  color: #111;
}

/* ---- Page layout ---- */
.page-container {
  max-width: 800px;
  margin: 0 auto;
  padding: 0 24px;
}

.page-header {
  padding-top: 120px;
  padding-bottom: 48px;
}

.page-title {
  font-size: 2rem;
  font-weight: 700;
  letter-spacing: -0.03em;
  color: #111;
  margin-bottom: 12px;
}

.page-subtitle {
  font-size: 1.0625rem;
  color: #777;
  line-height: 1.6;
}

/* ---- Content typography ---- */
.content-section {
  margin-bottom: 48px;
}

.content-section h2 {
  font-size: 1.375rem;
  font-weight: 600;
  letter-spacing: -0.02em;
  color: #111;
  margin-bottom: 16px;
}

.content-section h3 {
  font-size: 1.0625rem;
  font-weight: 600;
  color: #111;
  margin-bottom: 12px;
}

.content-section p {
  font-size: 0.9375rem;
  line-height: 1.7;
  color: #444;
  margin-bottom: 12px;
}

.content-section p:last-child {
  margin-bottom: 0;
}

.content-section ul,
.content-section ol {
  font-size: 0.9375rem;
  line-height: 1.7;
  color: #444;
  padding-left: 20px;
  margin-bottom: 12px;
}

.content-section li {
  margin-bottom: 6px;
}

.text-link {
  color: #111;
  text-decoration: underline;
  text-underline-offset: 2px;
  text-decoration-color: #ccc;
  transition: text-decoration-color 0.2s;
}

.text-link:hover {
  text-decoration-color: #111;
}

/* ---- Page bottom spacing ---- */
.page-bottom {
  padding-bottom: 96px;
}

/* ---- Responsive ---- */
@media (max-width: 640px) {
  .nav-toggle {
    display: block;
  }

  .nav-links {
    display: none;
    position: absolute;
    top: 56px;
    left: 0;
    right: 0;
    background: rgba(255, 255, 255, 0.98);
    backdrop-filter: blur(8px);
    -webkit-backdrop-filter: blur(8px);
    flex-direction: column;
    padding: 16px 24px;
    gap: 16px;
    border-bottom: 1px solid rgba(0, 0, 0, 0.06);
  }

  .nav-links.open {
    display: flex;
  }

  .footer-inner {
    flex-direction: column;
    gap: 24px;
  }

  .footer-links {
    flex-direction: column;
    gap: 12px;
  }

  .page-header {
    padding-top: 96px;
    padding-bottom: 36px;
  }

  .page-title {
    font-size: 1.625rem;
  }

  .page-subtitle {
    font-size: 0.9375rem;
  }

  .content-section h2 {
    font-size: 1.1875rem;
  }
}