Requirement • Explanation • Tutorial
Section 508 Requirement
(d) Cascading Style Sheets:
Documents shall be organized so they are readable without requiring an associated style sheet.
A cascading style sheet (CSS) allows the Web developer to separate content from presentation. Styles can be applied to many page attributes including: font color and size, positioning and spacing, background, margins, etc.
There are many advantages to using CSS on your Web pages. Two of the biggest advantages are:
- Faster loading Web pages » By removing all font tags from the html, coding is kept lean.
- Effortless site-wide changes » When using an external CSS (recommended over importing), all style changes can be made in one master file and filtered throughout the entire site.
Even if only used to apply font colors, problems can occur if a CSS is not used properly. For instance, if the font color "white" is defined in the style sheet and a background color of "black" in assigned in the BODY tag of the HTML, then the text would appear black on a black background with the style sheet turned off, making the resulting content totally invisible to the user.
The Web visitors most affected by rule "d" include:
- those users who turn off style sheets
- individuals with older browsers that do not fully support CSS
- users who rely upon assistive technologies, such as screen readers
The majority of Winthrop Web authors using CSS will be doing so to manage font attributes exclusively. For these individuals, rule "d" will most likely have no impact on their pages. For those Web authors who use CSS often and wish to test pages against rule "d" of Section 508, read the tutorial below.
There are several ways to test your Web pages for accessibility when CSS are disabled.
- Disable CSS in your browser preferences. » Disabling styles sheets in Opera and Netscape is very simple. Doing so in Internet Explorer for Mac is also fairly easy, but IE for Windows may be difficult, if not impossible.
- Remove the CSS file from your Web. » The method that I have found to be most effective is to create a copy of the CSS by downloading it to your hard drive. AFTER making a back up copy, delete the original CSS from your Web. View the site without the CSS. If it is readable and makes sense, then your site meets the requirement. Be sure to upload your CSS back to your Web.
For your convenience, you may also wish to download a printer-friendly Section 508 checklist (pdf).
For additional assistance with this requirement, send an email to firstname.lastname@example.org.