.back-to-top{left:50%;right:auto;transform:translateX(-50%);}
.call-fab{position:fixed;right:15px;bottom:15px;width:52px;height:52px;border-radius:50%;background:#77a1f7;color:#fff;display:flex;align-items:center;justify-content:center;font-size:22px;box-shadow:0 4px 14px rgba(0,0,0,.25);z-index:10;text-decoration:none;transition:background .2s,transform .2s;}
.call-fab:hover{background:#4a7cf0;color:#fff;transform:translateY(-2px);}
@media (max-width:575.98px){.call-fab{width:56px;height:56px;font-size:24px;}}