How to Change CSS Colors from Custom Plugin Settings Page

Nevermind, the last option was actually working, but in my own CSS code I found that I was overriding it. I cleaned up my CSS and it’s working with the function I posted above. I also found an alternative method using wp_add_inline_style() which got me to look at my CSS code in more depth. Example code below:

function wpdocs_styles_method() {
    wp_enqueue_style(
        'custom-um-style',
        plugin_dir_path(__FILE__) . 'includes/plugins/ultimate-member/ultimate-member.css'
    );
        $color = get_option('eri_um_account_menu_bg'); //E.g. #FF0000
        $custom_css = "
                .um-account-side li {
                        background: {$color} !important;
                }";
        wp_add_inline_style( 'custom-um-style', $custom_css );
}
add_action( 'wp_enqueue_scripts', 'wpdocs_styles_method' );