text-align实现的右外侧定位

HTML

<div class="constr">
    <div class="alignright">
        <span class="follow">
            <img src="circle.png">
            <img src="backtop.png">
        </span>
    </div>
</div>
					    

CSS

.constr {
    width: 80%;
    margin: auto;
    background-color: #f0f3f9;
}
.alignright {
    height: 0;
    text-align: right;
    overflow: hidden;
}
.alignright:before {
    content: "\2002";
}

.follow {
    position: fixed;
    bottom: 100px;
    z-index: 1;
}
.follow > img {
    display: block;
    margin: 10px;
}
					    

JS

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