Why doesn't z-index work? - what's the deal with its values?
The z-index is one of the essential elements of CSS that allows you to control the layering of elements on a web page. The article discusses how z-index works and why it is so important. It only affects elements with a defined position (relative, absolute, fixed, sticky). This means that without setting the position, z-index has no effect on an element. Using z-index allows the creation of complex layouts where one element can be placed above another, which is critical in responsive web design. Examples of practical applications of z-index illustrate how this property can achieve desired visual effects, such as displaying modal windows or dropdown menus. Therefore, understanding z-index is crucial for any web developer.