Pure CSS Tooltips

HTML

<div class="wrapper">Your Rocky Link
    <div class="tooltip">The description goes here...</div>
</div>

<div class="wrapper">Your Rocky Link 2
    <div class="tooltip">The description goes here...</div>
</div>

CSS

.wrapper {
    text-transform: uppercase;
    background: #ececec;
    color: #555;
    cursor: pointer;
    font-family:"Gill Sans", Impact, sans-serif;
    font-size: 20px;
    margin: 100px 75px 10px 75px;
    padding: 15px 20px;
    position: relative;
    text-align: center;
    width: 200px;
    -webkit-transform: translateZ(0);
    -webkit-font-smoothing: antialiased;
}
.wrapper .tooltip {
    background: #1496bb;
    bottom: 100%;
    color: #fff;
    display: block;
    left: -25px;
    margin-bottom: 15px;
    opacity: 0;
    padding: 20px;
    pointer-events: none;
    position: absolute;
    width: 100%;
    -webkit-transform: translateY(10px);
    -moz-transform: translateY(10px);
    -ms-transform: translateY(10px);
    -o-transform: translateY(10px);
    transform: translateY(10px);
    -webkit-transition: all .25s ease-out;
    -moz-transition: all .25s ease-out;
    -ms-transition: all .25s ease-out;
    -o-transition: all .25s ease-out;
    transition: all .25s ease-out;
    -webkit-box-shadow: 2px 2px 6px rgba(0, 0, 0, 0.28);
    -moz-box-shadow: 2px 2px 6px rgba(0, 0, 0, 0.28);
    -ms-box-shadow: 2px 2px 6px rgba(0, 0, 0, 0.28);
    -o-box-shadow: 2px 2px 6px rgba(0, 0, 0, 0.28);
    box-shadow: 2px 2px 6px rgba(0, 0, 0, 0.28);
}
.wrapper .tooltip:before {
    bottom: -20px;
    content:" ";
    display: block;
    height: 20px;
    left: 0;
    position: absolute;
    width: 100%;
}
/* CSS Triangles - see Trevor's post */
 .wrapper .tooltip:after {
    border-left: solid transparent 10px;
    border-right: solid transparent 10px;
    border-top: solid #1496bb 10px;
    bottom: -10px;
    content:" ";
    height: 0;
    left: 50%;
    margin-left: -13px;
    position: absolute;
    width: 0;
}
.wrapper:hover .tooltip {
    opacity: 1;
    pointer-events: auto;
    -webkit-transform: translateY(0px);
    -moz-transform: translateY(0px);
    -ms-transform: translateY(0px);
    -o-transform: translateY(0px);
    transform: translateY(0px);
}