.mb-0 > button:after {
    content: url('https://almacenesbomba.com/img/icons/expand-arrow--v1.png') !important; /* fa-chevron-down */
    font-family: 'Font Awesome 5 Free' !important;
    position: absolute !important;
    right: 10px !important;
}
.mb-0 > button[aria-expanded="true"]:after {
    content: url('https://almacenesbomba.com/img/icons/collapse-arrow.png') !important; /* fa-chevron-up */
}
.loader {
    border: 16px solid #f3f3f3; /* Light grey */
    border-top: 16px solid #3498db; /* Blue */
  
    animation: spin 2s linear infinite;
}

@keyframes spin {
    0% { transform: rotate(0deg); }
    100% { transform: rotate(360deg); }
}