:last-child
only works when the element in question is the last child of the container, not the last of a specific type of element. For that, you want :last-of-type
As per @BoltClock’s comment, this is only checking for the last article
element, not the last element with the class of .comment
.
body {
background: black;
}
.comment {
width: 470px;
border-bottom: 1px dotted #f0f0f0;
margin-bottom: 10px;
}
.comment:last-of-type {
border-bottom: none;
margin-bottom: 0;
}
<div class="commentList">
<article class="comment " id="com21"></article>
<article class="comment " id="com20"></article>
<article class="comment " id="com19"></article>
<div class="something"> hello </div>
</div>