3. To make it clear later where your CSS is coming from, rename the file from Styles.css to
Monochrome.css. You can rename it by selecting it and pressing F2 or by right-clicking it and
choosing Rename.
4. Because the main layout is now going to be controlled by the theme, you no longer need the
element in the section of the master page pointing to the old CSS file, so you can
remove it. To this end, open the MasterPage, switch to Markup View, and remove the following
highlighted line from the โค๊ด: