/* ELEMENT selector example */
body {
  font-family: system-ui, -apple-system, Segoe UI, Roboto, Arial, sans-serif;
  line-height: 1.6;
  margin: 0;
  padding: 0;
  background: #f9fafb;
  color: #111827;
}

/* ID selector examples */
#hero {
  background: #111827;
  color: #f9fafb;
  padding: 2rem 1rem;
  text-align: center;
}

#footer-note {
  text-align: center;
  font-size: 0.9rem;
  color: #6b7280;
  padding: 2rem 0 3rem;
}

/* CLASS selector examples */
.tagline {
  margin: 0.25rem 0 0;
  font-style: italic;
  color: #d1d5db;
}

.illustration {
  max-width: 520px;
  width: 100%;
  height: auto;
  display: block;
  margin: 1rem auto;
  border-radius: 8px;
  box-shadow: 0 6px 20px rgba(0,0,0,0.08);
}

.tip {
  text-align: center;
  font-size: 0.95rem;
  color: #374151;
}

/* Layout polish */
main {
  max-width: 900px;
  margin: 0 auto;
  padding: 1.25rem;
  background: white;
}

h1, h2, h3 {
  margin-top: 1.5rem;
}

a {
  text-decoration: none;
  border-bottom: 1px solid #93c5fd;
}

a:hover {
  border-bottom-color: #2563eb;
}