Adding CSS styles into WooCommerce emails

WooCommerce emails can have CSS inline styles added via an action hook woocommerce_email_header, to add your CSS styles use the hook like below…

add_action( 'woocommerce_email_header', 'bt_add_css_to_email' );

/**

 * WooCommerce

 * Add inline CSS to emails sent out

 */

function bt_add_css_to_email() {

    echo '

<style type="text/css">

        h1 {

        text-align: center !important;

        color: #c7c9c7;

        }

        </style></pre>

'; }
The styles will be output in the header of the email.