Click open/close Dropdown in pure CSS

dabblet.css

/* Click open/close Dropdown in pure CSS */

.tabs {
    position: relative;
    clear: both;
    margin: 50px;
}
.tab {
    float: left;
    position: relative;
}
.tab label {
    background: -webkit-linear-gradient(#eee, #ccc);
    padding: 10px 30px;
    cursor: pointer;
    text-align: center;
    display: block;
    position: relative;
}
.tab label i {
    font-style: normal;
    font-size: 10px;
    color: #aaa;
}
.tab [type=radio] {
    position: absolute;
    top: 0;
    left: 0;
    width: 100%;
    height: 100%;
    opacity: 0;
    margin: 0;
}
.content {
    position: absolute;
    top: 100%;
    opacity: 0;
    left: 0;
    background: #333;
    color: white;
    padding: 20px;
}
[type=radio]:checked ~ label {
    z-index: 2;
}
[type=radio]:checked ~ label ~ .content {
    z-index: 1;
    opacity: 1;
}

.close-tab {
    position: absolute;
    z-index: -1;
    top: 0;
    left: 0;
    width: 100%;
    height: 100%;
}
.close-tab label {
    background: #333;
    color: white;
}
[type=radio]:checked ~ label ~ .close-tab {
    z-index: 3;
}

dabblet.html

<div class="tabs">

    <div class="tab">
        <input type="radio" id="tab-1" name="tab-group-1">
        <label for="tab-1">List 1 <i>▼</i></label>
        <div class="tab close-tab">
            <input type="radio" id="tab-close" name="tab-group-1">
            <label for="tab-close">List 1 <i>▲</i></label>
        </div>

        <div class="content">
            Experemental dropdowns - adding "drop down" and a close button to the "pure CSS tabs" by Chris Coyier - <ahref="http://css-tricks.com/13758-functional-css-tabs-revisited/">http://css-tricks.com/13758-functional-css-tabs-revisited/</a>
        </div>
    </div>

    <div class="tab">
        <input type="radio" id="tab-2" name="tab-group-1">
        <label for="tab-2">List 2 <i>▼</i></label>
        <div class="tab close-tab">
            <input type="radio" id="tab-close" name="tab-group-1">
            <label for="tab-close">List 2 <i>▲</i></label>
        </div>

        <div class="content">
            Uses a second radio button within the tab which is grizzly I know but makes it collapsible.
        </div>
    </div>

    <div class="tab">
        <input type="radio" id="tab-3" name="tab-group-1">
        <label for="tab-3">List 3 <i>▼</i></label>
        <div class="tab close-tab">
            <input type="radio" id="tab-close" name="tab-group-1">
            <label for="tab-close">List 3 <i>▲</i></label>
        </div>

        <div class="content">
            Got really excited about getting this working, but sadly IOS crushed the JS free dream :(
        </div>
    </div>

</div>

settings.json

{"view":"split-vertical","prefixfree":"1","page":"css"}