.wfab{position:fixed;right:clamp(16px,2vw,28px);bottom:clamp(16px,2vw,28px);z-index:150;
  width:clamp(52px,5vw,60px);height:clamp(52px,5vw,60px);border-radius:50%;background:#25D366;
  display:flex;align-items:center;justify-content:center;box-shadow:0 12px 30px -6px rgba(0,0,0,.55);
  transition:.35s var(--ease)}
.wfab svg{width:54%;height:54%;fill:#fff}
.wfab:hover{transform:translateY(-3px) scale(1.06);box-shadow:0 18px 42px -8px rgba(0,0,0,.6)}
.wfab::before{content:"";position:absolute;inset:0;border-radius:50%;background:#25D366;z-index:-1;
  animation:wfab-pulse 2.6s ease-out infinite}
@keyframes wfab-pulse{0%{transform:scale(1);opacity:.45}70%,100%{transform:scale(1.75);opacity:0}}
@media(prefers-reduced-motion:reduce){.wfab::before{animation:none}}