.view-checkout .input-append,
.view-checkout .input-prepend {
    display: block;
}

.view-checkout .input-append button.hikabtn_checkout_coupon_add {
    background-color: #651b32;
    border-color: #651b32;
    border-radius: 0px;
    margin-top: 15px;
}

.view-checkout .input-append button.hikabtn_checkout_coupon_add:hover {
    background-color: #505456
}