/* Configuración General */
* {
    box-sizing: border-box;
    margin: 0;
    padding: 0;
    font-family: 'Segoe UI', Tahoma, Geneva, Verdana, sans-serif;
}

body {
    background: linear-gradient(135deg, #1e293b 0%, #0f172a 100%);
    height: 100vh;
    display: flex;
    justify-content: center;
    align-items: center;
    color: #f8fafc;
}

/* Contenedor Principal */
.principal {
    background: #ffffff;
    padding: 2.5rem;
    border-radius: 12px;
    box-shadow: 0 10px 25px rgba(0, 0, 0, 0.3);
    width: 100%;
    max-width: 400px;
    color: #1e293b;
}

h1 {
    text-align: center;
    margin-bottom: 1.5rem;
    color: #2563eb;
    font-size: 1.8rem;
}

/* Formulario */
.formulario label {
    display: block;
    margin-bottom: 0.5rem;
    font-weight: 600;
    font-size: 0.9rem;
}

.formulario input {
    width: 100%;
    padding: 0.75rem;
    margin-bottom: 1.2rem;
    border: 1px solid #cbd5e1;
    border-radius: 6px;
    outline: none;
    transition: border-color 0.3s;
}

.formulario input:focus {
    border-color: #2563eb;
}

/* Mensajes de error */
.mensaje-error {
    background: #fee2e2;
    color: #dc2626;
    padding: 0.75rem;
    border-radius: 6px;
    margin-bottom: 1rem;
    font-size: 0.85rem;
    text-align: center;
    border: 1px solid #fecaca;
}

/* Botones */
.botones {
    display: flex;
    flex-direction: column;
    gap: 0.75rem;
}

button {
    cursor: pointer;
    padding: 0.75rem;
    border: none;
    border-radius: 6px;
    font-weight: 600;
    font-size: 1rem;
    transition: all 0.3s;
}

/* Botón Enviar */
button[value="Enviar"] {
    background-color: #2563eb;
    color: white;
}

button[value="Enviar"]:hover {
    background-color: #1d4ed8;
}

/* Botón Salir */
button[value="Salir"] {
    background-color: #f1f5f9;
    color: #475569;
}

button[value="Salir"]:hover {
    background-color: #e2e8f0;
}