document.getElementById('stock_b5921').innerHTML = '<span style="color: red; font-weight: bold;">Out of Stock</span>.<br /><a href="https://www.kingwebtools.com/islamic_book_store/notify_stock.php?id=b5921&code=B5921&store=talkislam" style="color: #000000;" target="_blank">Please notify me when back in stock</a>';