If you want to use Bootstrap on your pen, go to the external stylesheets of the CSS section, type “Bootstrap”, select the option you want to use and include as many sources as you need !
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By default, every time you save your project runs and automatically updates the preview. You can save and run your project by clicking the “Save All + Run” button in the header . You can also use the keyboard shortcut to save your current file (Command + S for Mac, CTRL + S for PC).
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