.custom-heading {
    font-size: 1.5rem; /* Mobile first */
}

@media (max-width: 998px) { /* xl breakpoint */
    .custom-heading {
        font-size: 1.0rem;
    }
}

@media (max-width: 560px) { /* xl breakpoint */
    .custom-heading {
        font-size: 0.8rem;
    }
}