body { font-family: -apple-system, BlinkMacSystemFont, "Segoe UI", Roboto, sans-serif; margin: 0; min-height: 100vh; display: flex; flex-direction: column; background: #0d1117; color: #e6edf3; }
main { flex: 1; display: flex; align-items: center; justify-content: center; padding: 20px; }
h1 { font-size: 3rem; margin: 0; text-align: center; }