Try this:
<div class="toc-chap"><a href="xxxx">Chapter 1
</a></div>
<div class="toc-chap"><a href="xxx">Chapter 2
</a></div>
Add appropriate entry in css for class name like:
.toc-chap {
margin-top: 0.7em;
margin-bottom: 0;
margin-left: 3em;
text-indent: -2em;
}
Then at Chapter x location, avoid using self-closing tags.
<div id=xxx>
</div>
<a id=xxx name=xxx>
</a>
In some ereader software, self-closing tags as used in your example would create a link from that location onward until the computer finds something that stops it, like the end of the page.