.bg-principal {
    background: #6da9dc;
}
.bg-secundario {
    background: #a7abb1;
}
.gradient-custom {
    /* fallback for old browsers */
    background: #e6e9f0;

    /* Chrome 10-25, Safari 5.1-6 */
    background: -webkit-linear-gradient(to right, rgba(230, 233, 240, 0.5), rgba(238, 241, 245, 0.5));

    /* W3C, IE 10+/ Edge, Firefox 16+, Chrome 26+, Opera 12+, Safari 7+ */
    background: linear-gradient(to right, rgba(230, 233, 240, 0.5), rgba(238, 241, 245, 0.5));
}