body {
  background: #16161a;
  color: #fffffe;
  font-family: 'Segoe UI', Arial, sans-serif;
  min-height: 100vh;
  margin: 0;
  padding: 0;
}
.container {
  background: #242629;
  margin: 40px auto;
  max-width: 400px;
  border-radius: 10px;
  padding: 32px 24px;
  box-shadow: 0 8px 24px rgba(0,0,0,0.18);
}
h1 {
  text-align: center;
  margin-bottom: 18px;
  font-size: 1.4rem;
  color: #7f5af0;
}
form label {
  display: block;
  margin: 12px 0 6px;
}
input[type="number"] {
  width: 80px;
  padding: 4px;
  border-radius: 4px;
  border: none;
  margin-bottom: 10px;
  font-size: 1rem;
}
.checkbox-group {
  display: flex;
  flex-direction: column;
  gap: 5px;
  margin-bottom: 16px;
}
.checkbox-group label {
  font-size: 0.98rem;
}
button[type="submit"] {
  background: #7f5af0;
  color: #fffffe;
  border: none;
  padding: 10px 0;
  width: 100%;
  font-size: 1rem;
  border-radius: 6px;
  cursor: pointer;
  margin-top: 8px;
  transition: background 0.2s;
}
button[type="submit"]:hover {
  background: #6245c8;
}
#result {
  display: flex;
  align-items: center;
  margin-top: 18px;
  gap: 8px;
}
#passwordOutput {
  flex: 1;
  padding: 8px;
  border-radius: 5px;
  border: none;
  font-size: 1.1rem;
  background: #16161a;
  color: #fffffe;
  letter-spacing: 0.04em;
}
#copyBtn {
  background: #2cb67d;
  color: #22223b;
  border: none;
  padding: 8px 10px;
  font-size: 1rem;
  border-radius: 5px;
  cursor: pointer;
  transition: background 0.2s;
}
#copyBtn:hover {
  background: #22915f;
}
#feedback {
  margin-top: 10px;
  color: #2cb67d;
  font-size: 0.98rem;
  text-align: center;
  min-height: 1.2em;
}