Edit in JSFiddle

<div class="star">★<br /><span>click me</span></div>

.star {
    font-size: 40px;
    background: #C9C9C9;
    padding: 20px;
    width: 100px;
    text-align: center;
    border-radius: 6px;
    margin: 20px auto 0 auto;
    cursor: pointer;
    line-height: 20px;
    transition-property: background;
    -moz-transition-property: background; /* Firefox 4 */
    -webkit-transition-property: background; /* Safari and Chrome */
    -o-transition-property: background;
    transition-duration: 500ms;
    -webkit-transition-duration: 500ms;
}
.star:hover {
    background: #959595;
    color: #FFF;
}
.star span {
    font-size: 16px;
    font-weight: bold;
}