body {
  font-family: Arial, sans-serif;
  margin: 0;
  padding: 0;
  background-color: #222;
  color: #f0f0f0;
}

header {
  background-color: #333;
  padding: 1rem;
  text-align: center;
}

header h1 {
  margin: 0;
}

nav {
  margin-top: 1rem;
  display: flex;
  justify-content: center;
  gap: 0.5rem;
  flex-wrap: wrap;
}

nav button {
  padding: 0.6rem 1rem;
  border: none;
  background-color: #444;
  color: #fff;
  cursor: pointer;
  border-radius: 4px;
}

nav button:hover {
  background-color: #555;
}

main {
  padding: 1rem;
}

.page {
  max-width: 480px;
  margin: 0 auto;
}

.card {
  background-color: #2d2d2d;
  padding: 1rem;
  border-radius: 6px;
  box-shadow: 0 2px 4px rgba(0, 0, 0, 0.5);
}

label {
  display: block;
  margin-bottom: 0.5rem;
}

label input {
  width: 100%;
  padding: 0.5rem;
  margin-top: 0.2rem;
  border: 1px solid #555;
  border-radius: 4px;
  background-color: #3a3a3a;
  color: #f0f0f0;
}

button.guardar,
button.borrar {
  margin-top: 1rem;
  padding: 0.6rem 1rem;
  border: none;
  background-color: #007acc;
  color: #fff;
  cursor: pointer;
  border-radius: 4px;
}

button.guardar:hover,
button.borrar:hover {
  background-color: #0091e5;
}

.resultados {
  margin-top: 1rem;
  background-color: #1a1a1a;
  padding: 0.8rem;
  border-radius: 4px;
  white-space: pre-line;
}

table.historial {
  width: 100%;
  border-collapse: collapse;
  margin-top: 1rem;
}

table.historial th,
table.historial td {
  border: 1px solid #555;
  padding: 0.5rem;
  text-align: left;
}

table.historial th {
  background-color: #333;
}

table.historial tr:nth-child(even) {
  background-color: #2a2a2a;
}

footer {
  margin-top: 2rem;
  text-align: center;
  font-size: 0.8rem;
  color: #888;
}