* {
    box-sizing: border-box;
}

body {
    margin: 0;
    font-family: Arial, Helvetica, sans-serif;
    background: linear-gradient(135deg, #006b5f, #00a3b5);
    min-height: 100vh;
    padding: 30px 15px;
    color: #1f2933;
}

.contenedor {
    max-width: 850px;
    margin: auto;
    background: #ffffff;
    border-radius: 18px;
    box-shadow: 0 20px 45px rgba(0,0,0,0.22);
    overflow: hidden;
}

.cabecera {
    text-align: center;
    padding: 35px 20px 25px;
    background: #f7fbfb;
    border-bottom: 5px solid #006b5f;
}

.logo {
    width: 150px;
    max-width: 80%;
    margin-bottom: 10px;
}

h1 {
    margin: 5px 0;
    color: #006b5f;
    font-size: 30px;
    text-transform: uppercase;
}

.cabecera p {
    margin: 0;
    color: #0f766e;
    font-weight: bold;
    letter-spacing: 1px;
}

.formulario {
    padding: 30px;
}

h2 {
    color: #006b5f;
    border-left: 6px solid #f4b400;
    padding-left: 10px;
    margin-top: 20px;
}

label {
    display: block;
    margin-top: 15px;
    font-weight: bold;
    color: #374151;
}

span {
    color: #dc2626;
}

input, select, textarea {
    width: 100%;
    margin-top: 7px;
    padding: 13px;
    border: 1px solid #cbd5e1;
    border-radius: 10px;
    font-size: 15px;
    outline: none;
}

input:focus, select:focus, textarea:focus {
    border-color: #006b5f;
    box-shadow: 0 0 0 3px rgba(0, 107, 95, 0.15);
}

.grid {
    display: grid;
    grid-template-columns: 1fr 1fr;
    gap: 18px;
}

.nota {
    background: #f0fdfa;
    border-left: 5px solid #006b5f;
    padding: 12px;
    margin-top: 20px;
    border-radius: 8px;
    font-size: 14px;
}

button {
    width: 100%;
    margin-top: 25px;
    background: #006b5f;
    color: white;
    border: none;
    padding: 15px;
    border-radius: 12px;
    font-size: 17px;
    font-weight: bold;
    cursor: pointer;
    transition: 0.2s;
}

button:hover {
    background: #004d44;
}

.alerta {
    margin: 25px 30px 0;
    padding: 15px;
    border-radius: 10px;
    font-weight: bold;
    text-align: center;
}

.exito {
    background: #dcfce7;
    color: #166534;
    border: 1px solid #86efac;
}

.error {
    background: #fee2e2;
    color: #991b1b;
    border: 1px solid #fca5a5;
}

@media (max-width: 650px) {
    .grid {
        grid-template-columns: 1fr;
    }

    .formulario {
        padding: 22px;
    }

    h1 {
        font-size: 23px;
    }
}