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/*
replace the content value with the
corresponding value from the list below
*/

#text-2 h4.widget-title:before {
    content: "\f087";
    font-family: FontAwesome;
    font-style: normal;
    font-weight: normal;
    text-decoration: inherit;
/*--adjust as necessary--*/
    color: #000;
    font-size: 18px;
    padding-right: 0.5em;
    position: absolute;
    top: 0.2em;
    left: 0;
}

#text-2 h4.widget-title {
    padding-left: 1em;
}

<?php
//* Do NOT include the opening php tag shown above. Copy the code shown below.

// Make Font Awesome available
add_action( 'wp_enqueue_scripts', 'enqueue_font_awesome' );
function enqueue_font_awesome() {

    wp_enqueue_style( 'font-awesome', '//maxcdn.bootstrapcdn.com/font-awesome/latest/css/font-awesome.min.css' );

}