How to preview HTML 100% scale

Hi, am trying out Axure 9. I’m trying to do a mockup for a 4K resolution monitor (3840 x 2160) with my HD laptop (1920 x 1080). When I hit preview in Chrome, the Axure scale options are “Default scale”, “Scale to width”, “Scale to fit”. How do I scale the preview to 100%?

At “Scale to width”, it is not at 100% scale 'cos I can see the whole site without scrolling.

At “Default scale”, it is still not 100% scale, and for unknown reason it is pushed to the rightside. What does “Default scale” mean?

How do I preview in 100% scale (3840 x 2160) ? Such that I need to scroll sideways & topdown to view the full site. I set Chrome zoom to 100% but it only scale the Axure tool bar, & not the site.

Rgds
Thug

Found the solution. Currently I set the page dimension as “Custom Device” 3840 x 2160
image

When I set it to auto, I can preview the page as 100% scale in the browser
image