.input-file-wrapper{position:relative;z-index:0}.btn{border:1px solid gray;color:gray;background-color:#fff;padding:4px 10px;border-radius:4px}.input-file-wrapper input[type=file]{font-size:100px;position:absolute;z-index:0;left:0;top:0;right:0;bottom:0;opacity:0}.loader-in-btn{width:18px;height:18px;border:2px solid #fff;border-top:2px solid #ddd;border-radius:50%;animation:spin .6s linear infinite;vertical-align:middle;margin-left:6px}@keyframes spin{to{transform:rotate(360deg)}}