Google Gmail Screenshot
STATUS: Improvement Recommended Full Report »
Summary: One of the core recommendations we are proposing is support for embedded CSS in the head. While support for inline CSS is probably better than nothing, it isn't a solid alternative for true, standards-based support. Therefore, because of our recommendation, our acid test does not include inline CSS. Gmail does not support CSS unless it is inline. Consequently not a single item from our list is supported, nor is anything else. But even if Gmail supported embedded styles in the head of a document, it strips all IDs and classes from the source. So we would like to see Google remedy both of these ailments concurrently.
Note that these same issues also feature in the Gmail client for Android phones (eg. Google Nexus series), providing an inferior email experience in comparison to the excellent default email client on Android phones.
How Gmail handled our acid test:" OR logged_in_group_id == "1"}