Modify the existing HTML code so that it uses an external CSS file instead of inline CSS.

Start by creating a file called calendar.css and use the <link> tag in the header of calendar.html to link it to that page.

Then create CSS rules in calendar.css based on the style attributes of the HTML elements in calendar.html. Group the rules together based on elements class attributes and/or HTML element types, keeping the exact same styling rules.

When you are finished putting the CSS rules in calendar.css, delete the style attributes for all HTML elements in calendar.html and it should look the same.