The CSS1 Test Suite is provided as a free and open resource to the general Web community. It is hoped that implementors in particular will find the tests here to be of use in their continuing efforts to improve and refine their CSS rendering engines.
This suite aims to provide at least one test for each possible value of a property, and in some cases, combinations of those properties. The suite will be updated, if there are any changes to make, on the first day of each month. If a severe problem is found, such as an incorrect assertion or an error in the markup for a test, the suite may be updated before the next scheduled update. Previous versions of the suite will be kept, as well as a version history.
Through a blend of common interest and serendipity, three people came together to create the CSS1 Test Suite:
Håkon Lie of the World Wide Web Consortium (W3C) is a co-author of the original CSS1 specification. During the creation of this test suite, he contributed invaluable insight into the specification and checked each page for correctness and completeness. In addition, Håkon contributed some general test pages and some good ideas on flagging conformance.
Tim Boland of the National Institute of Standards and Technology (NIST) went to the effort of identifying more than five hundred testable statements in the CSS1 specification. Many of these statements were transferred directly into the final test suite, and much of Tim's work helped to verify that the test pages were correct in their assertions.
Eric Meyer of Case Western Reserve University (CWRU) had created his own test suite in order to create a set of compatibility charts for the Internet community's reference. The current test suite is very similar to Eric's original test pages; in effect, he took his existing set of pages and modified them for public release, grafting Tim's and Håkon's work to his own.
The CSS1 Test Suite was first opened for public comment in late April 1998, being housed on CWRU's Web server at that time. In early May 1998, the Suite was moved over to the W3C Web server and announced to the general public in a press release by the W3C.