Minification involves reducing data volume and file size by removing elements that reading systems do not require, such as whitespace, line breaks, and comments. Minified CSS files save bandwidth, which results in faster loading times and reduces the energy consumption associated with data transfer and rendering.

Objectives

• Minimize the amount of data to be downloaded.
• Improve performance.
• Reduce the environmental and energy impact of reading the ebook.

Implementation

• Use dedicated tools to remove unnecessary whitespace, line breaks, and comments from CSS files.

Control

• Manually verify that CSS files contain no line breaks, comments, indentations, or unnecessary whitespace.
• Alternatively, identify any unminified CSS files using developer tools, browser inspectors, or online validation tools.