You can reach a high level of customization of the Sticky ATC widget using the advanced custom CSS setting available under the 'Advanced' tab.
By using the class selector notation you can interact with the app DOM elements to get access to design options that aren't available in the Sticky Add to Cart design settings panel.
When selecting custom element classes from the app DOM always use names that have 'sticky' in their prefix e.g: 'stickyContainer'. Other class names that show on the element might change between app releases which occur often.
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