JSFiddle - React, Tailwind, and code Playground

HTML

<ol class="rectangle-list">
    <li><a href="">ZORNET.RU</a></li>
    <li><a href="">Скрипты для сайта</a></li>
    <li><a href="">Шаблоны портала</a></li>
    <li><a href="">Вебмастеру</a></li>
    <li><a href="">Позновательные статьи</a></li>
</ol>

CSS

.rectangle-list a {
 position: relative;
 display: block;
 padding: .4em .4em .4em .8em;
 *padding: .4em;
 margin: .5em 0 .5em 2.5em;
 background: #ddd;
 color: #444;
 text-decoration: none;
 -webkit-transition: all .3s ease-out;
 -moz-transition: all .3s ease-out;
 -ms-transition: all .3s ease-out;
 -o-transition: all .3s ease-out;
 transition: all .3s ease-out; 
}
 
.rectangle-list a:hover {
 background: #eee;
} 
 
.rectangle-list a:before {
 content: counter(li);
 counter-increment: li;
 position: absolute; 
 left: -2.5em;
 top: 50%;
 margin-top: -1em;
 background: #fa8072;
 height: 2em;
 width: 2em;
 line-height: 2em;
 text-align: center;
 font-weight: bold;
}
 
.rectangle-list a:after {
 position: absolute; 
 content: '';
 border: .5em solid transparent;
 left: -1em;
 top: 50%;
 margin-top: -.5em;
 -webkit-transition: all .3s ease-out;
 -moz-transition: all .3s ease-out;
 -ms-transition: all .3s ease-out;
 -o-transition: all .3s ease-out;
 transition: all .3s ease-out; 
}
 
.rectangle-list a:hover:after {
 left: -.5em;
 border-left-color: #fa8072; 
}

ol{
 counter-reset: li;
 list-style: none;
 *list-style: decimal;
 font: 15px 'trebuchet MS', 'lucida sans';
 padding: 0;
 margin-bottom: 4em;
 text-shadow: 0 1px 0 rgba(255,255,255,.5);
}

ol ol{
 margin: 0 0 0 2em;
}