Adding custom icons to ACF radio buttons.

functionality.php

/* ===========================================
    Radio Button Icons in Admin for ACF
   =============================================*/

function sr_acf_radio_style() {
	
    echo '<link rel="stylesheet" href="' . plugins_url( 'css/jazz.css', __FILE__) . '" type="text/css" media="screen" />';
}

add_action('admin_head', 'sr_acf_radio_style');

jazz.css

@font-face {
    font-family: 'icomoon';
    src:url('../fonts/icomoon.eot?-wdeksb');
    src:url('../fonts/icomoon.eot?#iefix-wdeksb') format('embedded-opentype'),
        url('../fonts/icomoon.woff?-wdeksb') format('woff'),
        url('../fonts/icomoon.ttf?-wdeksb') format('truetype'),
        url('../fonts/icomoon.svg?-wdeksb#icomoon') format('svg');
    font-weight: normal;
    font-style: normal;
}

[id^="acf-field-page_icon-"], [id*="acf-field-page_icon-"] {
    font-family: 'icomoon';
    speak: none;
    font-style: normal;
    font-weight: normal;
    font-variant: normal;
    text-transform: none;
    line-height: 1;

    /* Better Font Rendering =========== */
    -webkit-font-smoothing: antialiased;
    -moz-osx-font-smoothing: grayscale;
}

ul.acf-radio-list li input[id^="acf-field-page_icon-"], ul.acf-radio-list li input[id*="acf-field-page_icon-"] {
	margin-right: 24px !important;
}

[id^="acf-field-page_icon-"]:after, [id*="acf-field-page_icon-"]:after {
	position: absolute;
	top: 4px;
	left: 20px;
	font-size: 18px;
}

.acf-radio-list label {
	position: relative;
}

#acf-field-page_icon-house:after {
	content: "\e600";
}

#acf-field-page_icon-video:after {
    content: "\e600";
}
#acf-field-page_icon-users:after {
    content: "\e601";
}
#acf-field-page_icon-user:after {
    content: "\e602";
}
#acf-field-page_icon-heart:after {
    content: "\e603";
}
#acf-field-page_icon-chat:after {
    content: "\e604";
}
#acf-field-page_icon-calendar:after {
    content: "\e605";
}
#acf-field-page_icon-bulb:after {
    content: "\e606";
}
#acf-field-page_icon-time:after {
    content: "\e607";
}
#acf-field-page_icon-gear:after {
    content: "\e608";
}
#acf-field-page_icon-book:after {
    content: "\e609";
}
#acf-field-page_icon-bank:after {
    content: "\e60a";
}
#acf-field-page_icon-pie:after {
    content: "\e60b";
}
#acf-field-page_icon-pdf:after {
    content: "\e60c";
}
#acf-field-page_icon-new:after {
    content: "\e60d";
}
#acf-field-page_icon-info:after {
    content: "\e60e";
}
#acf-field-page_icon-house:after {
    content: "\e60f";
}
#acf-field-page_icon-graph:after {
    content: "\e610";
}
#acf-field-page_icon-form:after {
    content: "\e611";
}
#acf-field-page_icon-email:after {
    content: "\e612";
}
#acf-field-page_icon-directory:after {
    content: "\e613";
}