/* HTML
<div id="strength_indicator" class="no_pass"></div>
*/

/* CSS */
.no_pass {
    border-style: solid;
    border-width: 1px;
    background-color: white;
}

.weak_pass {
    border-style: solid;
    border-width: 1px;
    background-color: red;
}

.medium_pass {
    border-style: solid;
    border-width: 1px;
    background-color: yellow;
}

.strong_pass {
    border-style: solid;
    border-width: 1px;
    background-color: green;
}