select.form-select {
    background-color: #09579d;
    color: white !important;
    background-image: linear-gradient(45deg, transparent 50%, white 50%), linear-gradient(135deg, white 50%, transparent 50%);
    background-position: calc(100% - 20px) calc(1em + 2px), calc(100% - 15px) calc(1em + 2px), 100% 0;
    background-size: 5px 5px, 5px 5px, 2.5em 2.5em;
    background-repeat: no-repeat;
}

.selecciona {
    background-color: #e1e1e1 !important;
    color: #09579d !important;
}