
.btn .on-hover {
    display: none;
}

.btn:hover .on-hover {
    display: inline;
}

.btn:hover .on-display {
    display: none;
}

.btn {
  cursor: pointer;
}
.btn .on-hover {
    display: none;
}

.btn:hover .on-hover {
    display: inline;
}

.btn:hover .on-display {
    display: none;
}

Add cursor pointer to all .btn
Add cursor pointer to all .btn