Eventbrite button styling

Dear community, can you help? I know this has been asked before, but the code does not seem to work for me.

If successful, would this code change affect every Eventbrite button or would this need to be redone for each page with unique IDs.

On import the button is adopting correct font but not correct size or colour of button??

Eventbrite brite event code:
 

<!-- Noscript content for added SEO -->
<noscript><a href="https://www.eventbrite.co.uk/e/grease-outdoor-cinema-experience-at-east-sussex-national-hotel-uckfield-tickets-890977817637" rel="noopener noreferrer" target="_blank">Buy Tickets on Eventbrite</a></noscript>
<!-- You can customise this button any way you like -->
<button id="eventbrite-widget-modal-trigger-890977817637" type="button">BOOK TICKETS</button>

<script src="https://www.eventbrite.co.uk/static/widgets/eb_widgets.js"></script>

<script type="text/javascript">
    var exampleCallback = function() {
        console.log('Order complete!');
    };

    window.EBWidgets.createWidget({
        widgetType: 'checkout',
        eventId: '890977817637',
        modal: true,
        modalTriggerElementId: 'eventbrite-widget-modal-trigger-890977817637',
        onOrderComplete: exampleCallback
    });
</script>

You can share link to page in screenshot, we can help you with code easier.