HTML Web Object - Unwanted Side Gaps When Published from Storyline

I am experiencing an issue with an HTML Web Object in Articulate Storyline. When I add my custom HTML content as a Web Object to my slide, the HTML file displays perfectly full-screen in a web browser (e.g., Chrome) without any side gaps. However, in the published output of my Storyline project (either web or LMS), unwanted white spaces appear on the left and right sides of the area occupied by the Web Object. These gaps prevent my HTML content from completely filling the allotted space. I am confident that my Storyline Player settings ('Player Size: Scale player to fill browser window') are correctly configured. What steps should I take to resolve this issue and ensure my HTML content fills the screen entirely in the Storyline output?