/* Modo oscuro más amigable y moderno */
:root{
  --bg: #0f1113;
  --card: linear-gradient(180deg, rgba(255,255,255,0.02), rgba(255,255,255,0.01));
  --accent: #7f5af0;
  --accent-2: #2cb67d;
  --muted: #9aa4b2;
  --glass: rgba(255,255,255,0.03);
}

* { box-sizing: border-box; }

body {
  background: radial-gradient(1200px 600px at 10% 10%, rgba(127,90,240,0.06), transparent),
              radial-gradient(900px 400px at 90% 90%, rgba(44,182,125,0.04), transparent),
              var(--bg);
  color: #e6eef8;
  font-family: Inter, 'Segoe UI', Roboto, Arial, sans-serif;
  margin: 0;
  min-height: 100vh;
  display: flex;
  align-items: center;
  justify-content: center;
  padding: 24px;
  -webkit-font-smoothing:antialiased;
  -moz-osx-font-smoothing:grayscale;
}

/* Contenedor centrado */
.page {
  width: 100%;
  display: flex;
  align-items: center;
  justify-content: center;
}

.container {
  width: 100%;
  max-width: 460px;
  background: var(--card);
  border-radius: 14px;
  padding: 28px;
  box-shadow: 0 10px 30px rgba(2,6,23,0.6);
  border: 1px solid rgba(255,255,255,0.03);
  backdrop-filter: blur(6px);
}

/* Título y subtítulo */
h1 {
  margin: 0 0 6px;
  font-size: 1.35rem;
  color: var(--accent);
  text-align: center;
}

.subtitle {
  margin: 0 0 18px;
  font-size: 0.95rem;
  color: var(--muted);
  text-align: center;
}

/* Formulario */
form label {
  display: block;
  margin-bottom: 8px;
  font-size: 0.95rem;
  color: #d7e0f0;
}

input[type="number"] {
  width: 100px;
  padding: 8px 10px;
  border-radius: 8px;
  border: 1px solid rgba(255,255,255,0.04);
  margin-bottom: 12px;
  font-size: 1rem;
  background: var(--glass);
  color: #e6eef8;
}

/* Checkboxes verticales y espacios */
.checkbox-group {
  display: flex;
  flex-direction: column;
  gap: 8px;
  margin-bottom: 16px;
}

.checkbox-group label {
  display: flex;
  align-items: center;
  gap: 10px;
  background: rgba(255,255,255,0.01);
  padding: 8px 10px;
  border-radius: 8px;
  cursor: pointer;
  font-size: 0.95rem;
  color: #dbe9ff;
}

.checkbox-group input[type="checkbox"] {
  width: 16px;
  height: 16px;
  accent-color: var(--accent);
}

/* Botones */
button.primary {
  background: linear-gradient(180deg, var(--accent), #6245c8);
  color: #fff;
  border: none;
  padding: 12px 14px;
  width: 100%;
  font-size: 1rem;
  border-radius: 10px;
  cursor: pointer;
  box-shadow: 0 6px 18px rgba(127,90,240,0.12);
  transition: transform .08s ease, box-shadow .12s ease;
}

button.primary:hover { transform: translateY(-2px); }
button.primary:active { transform: translateY(0); box-shadow: none; }

.result {
  display: flex;
  align-items: center;
  gap: 10px;
  margin-top: 18px;
}

#passwordOutput {
  flex: 1;
  padding: 12px 14px;
  border-radius: 10px;
  border: 1px solid rgba(255,255,255,0.04);
  font-size: 1.05rem;
  background: rgba(255,255,255,0.02);
  color: #fff;
  letter-spacing: 0.04em;
  user-select: all;
}

/* Botón de copiar */
.copy {
  background: linear-gradient(180deg, var(--accent-2), #1f8d63);
  color: #081018;
  border: none;
  padding: 10px 12px;
  font-size: 0.95rem;
  border-radius: 10px;
  cursor: pointer;
  transition: transform .08s ease;
}

.copy:hover { transform: translateY(-2px); }
.copy:active { transform: translateY(0); }

/* Feedback / mensaje breve */
.feedback {
  margin-top: 12px;
  color: #9ee6c1;
  font-size: 0.95rem;
  text-align: center;
  min-height: 1.2em;
  transition: opacity .18s;
}

/* Responsivo */
@media (max-width: 520px) {
  .container { padding: 20px; }
  input[type="number"] { width: 90px; }
}