body { background-color: black; color: white; font-family: monospace; display: flex; justify-content: center; align-items: center; height: 100vh; margin: 0; } .error-box { background-color: black; border: 1px solid white; padding: 20px; max-width: 600px; } .error-box h1 { font-size: 2em; margin: 0; color: red; }