これらの要素があり、不透明度が 1 の ul 内の li を選択する必要があります。これどうやってするの?
<ul class="class" id="ul">
<li style="width: 100%; list-style: none outside none; position: absolute; top: 0px; left: 0px; z-index: 98; opacity: 0;"><a title="title1" href=""><img alt="alt" class="class_name" src="/images/7dfc294d5c3bcebecb2ec0e44fd27d1c.jpg"></a></li>
<li style="width: 100%; list-style: none outside none; position: absolute; top: 0px; left: 0px; z-index: 98; opacity: 0;"><a title="title2" href=""><img alt="alt" class="class_name " src="/images/a9c9eb42934df4576b352d88f607f292.jpg"></a></li>
<li style="width: 100%; list-style: none outside none; position: absolute; top: 0px; left: 0px; z-index: 98; opacity: 0;"><a title="title3" href=""><img alt="alt" class="class_name " src="/images/b64264692c0d648068c9d1380e9099c1.jpg"></a></li>
<li style="width: 100%; list-style: none outside none; position: absolute; top: 0px; left: 0px; z-index: 99; opacity: 1;"><a title="title4" href=""><img alt="alt" class="class_name " src="/images/43e3e5e2edc4234ecddbc89636e4e224.jpg"></a></li>
<li style="width: 100%; list-style: none outside none; position: absolute; top: 0px; left: 0px; z-index: 98; opacity: 0;"><a title="title5" href=""><img alt="e-alt" class="class_name " src="/images/31a156ce7f7ab5485366d24f6cbfbede.jpg"></a></li>
</ul>