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Theming is accomplished primarily through the use of dedicated CSS files for each resort, contained within a Theme folder. Other things When the Resorts Store loads, their theme CSS gets applied to the DOM after any application specific CSS, overriding default values as needed to achieve the desired theme results.
Other items that their theme folders include contain are images, logos, fonts (if embedding), theme config files, and custom header/footer files. When working on themes, you will be updating all of these files in the creation theming process. 90% of the theme set-up is accomplished through the editing of resort specific SCSS files contained in their theme folders. More details on the specific theme setup process can be found here: Step By Step Theme Guide
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