.del-box{overflow:hidden;width:40px;height:40px;}    
.del-ico{position:relative;left:-40px;display:inline-block;width:80px;height:40px;border-right:40px solid transparent;filter:drop-shadow(40px 0 #ff0);}

<div class="del-box">				
    <img class="del-ico" src="../../../img/icon/del.png" alt="">			
</div>

隐藏元素的话使用display: none;