如何解决移动端ios不兼容背景图片视觉滚动差

//css
```css
.about_img{
    height:100%;
    background-image:url(../img/gy1.jpg);
    background-position: center center ; 
    background-repeat: no-repeat; 
    background-attachment: fixed;
    background-size: cover; 
    position: relative;
     overflow:hidden;
    padding:10px 5px;
    margin:5px 0;
}

//html
```html
<div class="about_img bimg">
            
</div>