*, *::before, *::after { box-sizing: border-box; }
body {
  font-family: 'Segoe UI', system-ui, -apple-system, sans-serif;
  margin: 0;
  padding: 0;
  background: #121218;
  color: #e0e0e8;
}
header {
  background: #1a1a24;
  color: #c8c8d8;
  padding: 14px 20px;
  border-bottom: 1px solid #2a2a3a;
}
header h1 {
  margin: 0;
  font-size: 1.15rem;
  font-weight: 600;
  letter-spacing: .03em;
}
main {
  padding: 20px;
}
footer {
  padding: 12px 20px;
  font-size: 0.8rem;
  color: #555568;
}