@media print,
screen and (min-width: 360px) {
    .btn-pc {
     display:none;
    }
    .btn-sp {
     display:block;
    }
}

@media print,
screen and (min-width: 737px) {
    .btn-pc {
         display:block;
     }
    .btn-sp {
         display:none;
     }
}