:root {
  --bg: #ffffff;
  --blue: #0b5ed7;
  --blue-dark: #07336a;
  --green: #2f9e44;
  --muted: #6c757d;
  --max-w: 1100px;
  --radius: 10px;
  --transition: 180ms ease;
}

body {
  margin: 0;
  font-family: system-ui, -apple-system, "Segoe UI", Roboto, "Helvetica Neue", Arial;
  background: var(--bg);
  color: var(--blue-dark);
  line-height: 1.6;
}

header {
  background: var(--blue);
  color: white;
  padding: 1rem 2rem;
  text-align: center;
}

header h1 {
  margin: 0;
  font-size: 1.8rem;
}

.container {
  width: min(94%, var(--max-w));
  margin: 2rem auto;
}

h2 {
  color: var(--green);
  margin-top: 2rem;
  font-size: 1.4rem;
}

h3 {
  color: var(--blue);
  margin-top: 1rem;
}

ul {
  padding-left: 1.2rem;
}

ul li {
  margin-bottom: 0.4rem;
}

.back-btn {
  display: inline-block;
  margin-top: 2rem;
  background: linear-gradient(90deg, var(--blue), var(--green));
  color: white;
  padding: 0.6rem 1.2rem;
  border-radius: 999px;
  text-decoration: none;
  font-weight: bold;
  transition: transform var(--transition), box-shadow var(--transition);
}

.back-btn:hover {
  transform: translateY(-2px);
  box-shadow: 0 6px 20px rgba(0,0,0,0.1);
}