Many simple design changes can be accomplished through your design theme's Cascading Style Sheet (CSS) file.
Shift4Shop's Support department cannot and will not assist with CSS design changes or coding of any kind, but information and tutorials on CSS are widely available online. Therefore, if you'd like to try your hand at editing your store's CSS file, here's how you can access it.
Through the Online Store Manager
Log into your Shift4Shop Online Store Manager and use the left navigation menu to:
Go to Settings > Design > Themes & Styles.
Next, click on the Open Template Editor button located under "Edit Template."
Look to the top right of the page and click on the Go to Folder menu.
Select your theme folder's CSS folder (It will be highlighted yellow and will be called "templates/[theme-name]/css").
Your store's CSS files will be shown. Clicking on one will allow you to edit it.
You can select the desired CSS file from the Theme & Styles Selection page.
To access the CSS file through FTP:
Connect to your store's FTP server.
Navigate to web/assets/templates/[theme folder]*/css.
*replace "[theme folder]" with your specifically installed theme name.
Download the "default_modified_temp.css."