Image file is shown on Wappler, but is invisible on the browser automatically

Hello,

I’m changing from only original CSS to use Bootstrap with Sass right now.
Then I got this strange phenomenon.

Image is shown on Wappler, but is invisible on the browser.
(I would like to display this “rim’s picture” as attached image above.

Please see attachments and please let me know how to solve this.

スクリーンショット 2020-02-25 14.17.492764×1456 520 KB

スクリーンショット 2020-02-25 14.18.562788×1426 933 KB

Thanks,
Miwa