body
{
    background: url('../images/fondos/fondo_principal.jpg') no-repeat top left fixed !important;
    -webkit-background-size: cover !important;
    -moz-background-size: cover !important;
    -o-background-size: cover !important;
    background-size: cover !important;
}
.card.card-opacity {
    background-color: rgba(255, 255, 255, 0.9) !important;
}
.card-header {
    border-bottom: none !important;
}
.card-body {
    padding-top: 30px;
}
.form-control {
    font-size: 20px;
}