/* Mặc định: ẩn FAB trên desktop */
.fab-wrap{display:none}

/* Mobile-only */
@media (max-width:640px){
  .nav-links{display:none}            /* ẩn 3 nút cũ */
  .fab-wrap{display:block;margin-left:auto;position:relative}
  .fab{
    width:44px;height:44px;border-radius:9999px;
    border:2px solid var(--border);background:var(--white);color:var(--green-700);
    display:grid;place-content:center;box-shadow:var(--shadow)
  }
  .fab:active{transform:scale(.98)}

  .fab-menu{
    position:absolute;right:0;top:52px;min-width:200px;
    background:var(--white);border:2px solid var(--border);
    border-radius:14px;padding:.35rem;box-shadow:var(--shadow);
    display:none;animation:drop .14s ease-out
  }
  .fab-wrap.open .fab-menu{display:block}
  .fab-menu a{
    display:block;padding:.6rem .8rem;border-radius:10px;color:var(--green-700)
  }
  .fab-menu a:hover{background:var(--green-600);color:var(--white)}
}

/* nhỏ hiệu ứng */
@keyframes drop{from{opacity:0;transform:translateY(-6px)}to{opacity:1;transform:translateY(0)}}