Align list items with custom CSS content before bullets

Question

I have this snippet of HTML:

<ul class="custom">
    <li data-bullet="a">Item 1</li>
    <li data-bullet="aa">Item 2</li>
    <li data-bullet="ab">Item 3.1<br/>Item 3.2</li>
    <li data-bullet="c">Item 4</li>
    <li data-bullet="d">Item 5</li>
    <li data-bullet="de">Item 6</li>
</ul>

and CSS:

.custom {
    list-style:none;
    padding:0;
    margin:0;
}
.custom li:before {
    display:inline-block;
    content:attr(data-bullet);
    width:50px;
}

/*
.custom {
    list-style:none;
    padding:0;
    margin:0;
}
.custom li:before {
    display:inline-block;
    content:attr(data-bullet);
    position:relative;
    top:0;
    left:-50px;
}
.custom li {
    padding-left:50px;
}
*/

http://jsfiddle.net/g0w989aa/1/

It uses CSS before content of list items in order to create a custom list numbering. The problem is that the alignment of the text doesn't work properly if the content of the list item is longer than a single line.

Is there a way to align the content of the lines properly? I already tried to position the content relative and giving the list items a padding (see commented out css in example) but this doesn't work either.

Answer 1

Try offsetting the margin on the entire div by the width of the before and then take the margin off on the before after.

Like this:

.custom {
  list-style: none;
  padding: 0;
  margin: 0;
  margin-left: 50px;
}
.custom li:before {
  display: inline-block;
  content: attr(data-bullet);
  width: 50px;
  margin-left: -50px;
}

<ul class="custom">
  <li data-bullet="a">Item 1</li>
  <li data-bullet="aa">Item 2</li>
  <li data-bullet="ab">Item 3.1
    <br/>Item 3.2</li>
  <li data-bullet="c">Item 4</li>
  <li data-bullet="d">Item 5</li>
  <li data-bullet="de">Item 6</li>
</ul>

You can alternatively do it with positioning but you may hit snags with other elements being affected.