* {
  box-sizing: border-box;
  font-family: Arial, sans-serif;
}

body {
  margin: 0;
  background: #101010;
  color: white;
}

header {
  background: #d90429;
  padding: 25px;
  text-align: center;
}

header h1 {
  font-size: 45px;
  margin: 0;
}

nav {
  background: #222;
  padding: 15px;
  display: flex;
  justify-content: center;
  gap: 10px;
  flex-wrap: wrap;
}

nav a {
  text-decoration: none;
}

nav a button,
nav button {
  background: #d90429;
  color: white;
  border: 0;
  padding: 12px;
  border-radius: 8px;
  cursor: pointer;
  font-size: 15px;
}

nav a.activo button {
  background: #7a021a;
}

main {
  padding: 25px;
}

.card {
  background: #1e1e1e;
  max-width: 600px;
  margin: auto;
  padding: 25px;
  border-radius: 15px;
  box-shadow: 0 0 15px #000;
}

input,
textarea,
select {
  width: 100%;
  padding: 12px;
  margin: 8px 0;
  border-radius: 8px;
  border: 0;
}

textarea {
  height: 120px;
}

.btn {
  background: #d90429;
  color: white;
  border: 0;
  padding: 15px;
  border-radius: 10px;
  cursor: pointer;
  width: 100%;
  margin-top: 10px;
  font-size: 16px;
}

.btn:disabled {
  background: #6b6b6b;
  cursor: not-allowed;
}

.resultado {
  background: #333;
  padding: 15px;
  margin-top: 15px;
  border-radius: 10px;
}

.error {
  background: #4a1414;
  color: #ff8080;
}

.tarjetas {
  display: flex;
  gap: 15px;
  flex-wrap: wrap;
  justify-content: center;
}

.tarjeta {
  background: #222;
  padding: 20px;
  border-radius: 12px;
  width: 200px;
  text-align: center;
}

footer {
  text-align: center;
  padding: 20px;
  color: #888;
}
section{
  display: none;
}

.activo{
  display: block;
  }