body {
  margin: 0;
  background: #000;
  color: #fff;
  font-family: Arial, sans-serif;
}
.container {
  padding: 20px;
  max-width: 800px;
  margin: auto;
}
h1 {
  font-size: 2.5em;
  text-align: center;
  margin-bottom: 1em;
}
.card {
  background: #111;
  margin: 1em 0;
  padding: 1em;
  border-radius: 8px;
}
h2 {
  font-size: 1.5em;
  margin-bottom: 0.5em;
}
p, pre {
  font-size: 1.1em;
  white-space: pre-wrap;
}
@media (min-width: 768px) {
  h1 { font-size: 3em; }
  h2 { font-size: 2em; }
  p, pre { font-size: 1.3em; }
}