.mceButton.mce_hcshortcodes:before {
    content: "\f168";
    display: inline-block;
    -webkit-font-smoothing: antialiased;
    font: normal 19px/1 'dashicons';
    vertical-align: top;
}

.mce-ico.mce-i-hcshortcodes:before {
    content: "\f168";
    display: inline-block;
    -webkit-font-smoothing: antialiased;
    font: normal 19px/1 'dashicons';
    vertical-align: top;
}