.sticky-buy-btn{position:fixed;bottom:20px;left:50%;transform:translateX(-50%);background:#ff2b2b;color:white;padding:15px 30px;font-size:16px;font-weight:700;border-radius:40px;text-decoration:none;z-index:9999;box-shadow:0 5px 20px rgba(0,0,0,.2)}