Cũng như một số các tính năng hứa hẹn nhất của CSS, thông qua các tấm phong cách thay thế sẽ được phổ biến rộng rãi hơn nếu trình duyệt hỗ trợ mạnh mẽ hơn. Trong bài viết này, số lượng của các trình duyệt mà tự nhiên cho phép người dùng lựa chọn phong cách trang thay thế được giới hạn trong các trình duyệt dựa trên Gecko như Mozilla hoặc Firefox, trình duyệt Opera. | Chapter 8 Figure 8-5 With our understanding of how the cascade works we can build even more complexity into our alternate CSS documents. Another Solution We Almost Can t Quite Use As with some of the most promising features of CSS adoption of alternate style sheets would be more widespread if browser support were more robust. As of this writing the number of browsers that natively allow users to select alternate style sheets is limited to Gecko-based browsers such as Mozilla or Firefox and the Opera browser. For example Apple s Safari has no way to select alternate or preferred style sheets. And you guessed it Internet Explorer the browser known and loved the world over won t allow users to select the alternate user interfaces we build for them. If the world s most popular browser keeps this feature out of the hands of our users then we have a bit more work to do yet. 290 Stuff and Nonsense Strategies for CSS Switching Furthermore the browsers that do natively support alternate style sheet switching have only a limited switching functionality. While these browsers do allow the user to easily switch between the default CSS and any alternates provided by the author they do not remember the user s selection. This means that if a reader selects an alternate style sheet and then reloads the page or leaves and returns to it the browser will forget the earlier choice and reinstate the default style. Obviously neither of these scenarios will work for our users. We re lucky that there are some additional steps we can take to bring the full benefits of CSS switching to them. The Reality How It Can Work Today We ve established that most of our audience won t be able to use in-browser CSS switching and identified those who don t have much functionality available to them so we must build an interface into our page that allows users to overcome these limitations. Now you might realize that the two client-side technologies we ve been studying up to this point aren t especially .
