.activity-bubble{
  position:fixed;bottom:24px;right:24px;z-index:9999;
  max-width:280px;padding:12px 16px;
  background:rgba(220,38,38,.92);color:#fff;
  font-size:13px;font-weight:600;line-height:1.4;
  border-radius:12px;box-shadow:0 8px 24px rgba(0,0,0,.35);
  opacity:0;transform:translateY(20px) scale(.95);
  transition:opacity .35s ease,transform .35s ease;
  pointer-events:none;
}
.activity-bubble.show{opacity:1;transform:translateY(0) scale(1);}
.activity-bubble.hide{opacity:0;transform:translateY(10px) scale(.98);}