.wcb-btn {
    position: fixed;
    bottom: 25px;
    width: 65px;
    height: 65px;
    background: #25D366;
    border-radius: 50%;
    display: flex;
    justify-content: center;
    align-items: center;
    box-shadow: 0 0 15px rgba(0,0,0,0.25);
    z-index: 9999999;
    transition: transform .2s ease;
}
.wcb-btn:hover { transform: scale(1.1); }

.wcb-right { right: 25px; }
.wcb-left { left: 25px; }

.wcb-icon {
    width: 32px;
    height: 32px;
}

/* Responsive */
@media (max-width: 480px) {
    .wcb-btn {
        width: 55px;
        height: 55px;
    }
    .wcb-icon {
        width: 26px;
        height: 26px;
    }
}