body {
  background-color: #121212;
  color: #00bfff;
  font-family: monospace;
  text-align: center;
  margin: 0;
  padding: 0;
}
.container { margin-top: 50px; }
input {
  background-color: #1e1e1e;
  border: 1px solid #00bfff;
  color: #00bfff;
  padding: 10px;
  width: 300px;
}
button {
  background-color: #00bfff;
  color: #121212;
  border: none;
  padding: 10px 20px;
  cursor: pointer;
  margin: 5px;
}
button:hover { background-color: #0099cc; }
.output { margin-top: 30px; white-space: pre; font-size: 14px; }
footer {
  text-align: center;
  margin-top: 50px;
  color: #00bfff;
  font-size: 12px;
}