.center-block {
    display: block;
    margin: 0 auto;
}

body {
    background-color: #f5f5f5;
}

.container {
    max-width: 400px;
    margin: 40px auto;
    padding: 20px;
    background-color: #fff;
    border: 1px solid #ddd;
    box-shadow: 0 0 10px rgba(0,0,0,0.1);
}

.logo {
    width: 100px;
    height: 100px;
    margin: 20px auto;
    border-radius: 50%;
    background-color: #fff;
    padding: 10px;
    box-shadow: 0 0 10px rgba(0,0,0,0.1);
}

.error {
    color: red;
    font-size: 12px;
    margin-bottom: 10px;
}

.imagen-escalada {
    width: 100%;
    height: 100%;
}