body {
  margin: 0;
  padding: 0;
  font-family: -apple-system, BlinkMacSystemFont, 'Segoe UI', 'Roboto', sans-serif;
  background: linear-gradient(135deg, #000000 0%, #1a1a1a 100%);
  color: #fff;
}

* {
  box-sizing: border-box;
}

input:focus {
  outline: none;
}

button:hover {
  opacity: 0.9;
}