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Default CSS in Web & Desktop Email Clients
Table of content
It's important to beware!
It comes as no surprise that web clients use their own style sheets to render their pages. In the new version of Yahoo Mail and AIM Mail, emails are rendered inside an I-frame allowing for a fairly clean slate. However, in clients like G-Mail, Hotmail and Yahoo-Classic, they seem to make an attempt to reset browser defaults but several of their self-imposing styles are still carried over. This issue may actually challenge the notion that you are always safe using the basics when it comes to tables and divs. In fact if you didn't know that you needed to overwrite certain styles using embedded or inline CSS, your end result may look much different than expected. For example, Hotmail applies a margin value to its p, h1-h6, ul, and li elements and ironically they don't support the "margin" property in the rendered email itself. Fortunately they do support "margin-left," "margin-right," and "margin-bottom." In this instance, if you are using a background color or inserting images in any of these elements and you don't set a value for the above properties, you may see unwanted spacing in the end result.![Default CSS in Web & Desktop Email Clients](https://media.emailonacid.com/wp-content/uploads/2009/08/css_screenshots.gif)