css

Optional. Adds style classes for the component

css?: string;

Example

<style>
    .custom {
        --dhx-font-color-primary: var(--dhx-color-white);
        --dhx-background-primary: var(--dhx-color-primary);

        margin-top: 25px;
        animation: opacity .4s ease-in-out forwards;
    }
</style>

<script>
    const popup = new dhx.Popup({
        css: "dhx_widget--border-shadow custom"
    });
</script>

Related sample: Popup. Styling (custom CSS)

Note, that the DHTMLX library provides a set of own CSS classes that you can also apply to change the appearance of Popup.

const popup = new dhx.Popup({
    css: "dhx_widget--bg_white"
}); 

Related articles:

List of CSS classes for styling a widget
Themes

Example​

Example