可以将文章内容翻译成中文,广告屏蔽插件可能会导致该功能失效(如失效，请关闭广告屏蔽插件后再试):

问题:

I'm generating a html email that uses an internal stylesheet, i.e.

<!doctype html>
<html>
<head>
  <style type="text/css">
    h2.foo {color: red}    
  </style>
</head>
<body>
 <h2 class="foo">Email content here</foo>
</body>
</html>

When viewed in Gmail it seems all the styles in the internal stylesheet are ignored. It seems Gmail ignores all styles other than inline rules, e.g.

 <h2 style="color: red">Email content here</foo>

Is this my only option for styling HTML emails when viewed with Gmail?

回答1:

Use inline styles for everything. This site will convert your classes to inline styles: http://premailer.dialect.ca/

回答2:

The answers here are outdated, as of today Sep 30 2016. Gmail is currently rolling out support for the style tag in the head, as well as media queries. If Gmail is your only concern, you're safe to use classes like a modern developer!

For reference, you can check the official gmail CSS docs.

As a side note, Gmail was the only major client that didn't support style (reference, until they update anyway). That means you can almost safely stop putting styles inline. Some of the more obscure clients may still need them.

回答3:

Gmail started basic support for style tags in the head area. Found nothing official yet but you can easily try it yourself.
It seems to ignore class and id selectors but basic element selectors work.

<!doctype html>
<html>
  <head>
    <style type="text/css">
      p{font-family:Tahoma,sans-serif;font-size:12px;margin:0}  
    </style>
  </head>
  <body>
    <p>Email content here</p>
  </body>
</html>

it will create a style tag in its own head area limited to the div containing the mail body

<style>div.m14623dcb877eef15 p{font-family:Tahoma,sans-serif;font-size:12px;margin:0}</style>

回答4:

I agree with everyone who supports classes AND inline styles. You might have learned this by now, but if there is a single mistake in your style sheet, Gmail will disregard it.

You might think that your CSS is perfect, because you've done it so often, why would I have mistakes in my CSS? Run it through the CSS Validator (for example http://www.css-validator.org/) and see what happens. I did that after encountering some Gmail display issues, and to my surprise, several Microsoft Outlook specific style declarations showed up as mistakes.

Which made sense to me, so I removed them from the style sheet and put them into a only for Microsoft code block, like so:

<!--[if mso]>
<style type="text/css">
body, table, td, .mobile-text {
font-family: Arial, sans-serif !important;
}
</style>
<xml>
  <o:OfficeDocumentSettings>
    <o:AllowPNG/>
    <o:PixelsPerInch>96</o:PixelsPerInch>
  </o:OfficeDocumentSettings>
</xml>
<![endif]-->

This is just a simple example, but, who know, it might come in handy some time.

回答5:

As others have said, some email programs will not read the css styles. If you already have a web email written up you can use the following tool from zurb to inline all of your styles:

http://zurb.com/ink/inliner.php

This comes in extremely handy when using templates like those mentioned above from mailchimp, campaign monitor, etc. as they, as you have found, will not work in some email programs. This tool leaves your style section for the mail programs that will read it and puts all the styles inline to get more universal readability in the format that you wanted.

回答6:

Note that services and tools for sending emails may be able to inline your CSS for you, allowing CSS in <style> tags to work in Gmail.

For instance, if you're sending emails with MailChimp, your CSS from <style> tags will get inlined automatically by default. With Mandrill, you can enable this functionality (although it's disabled by default for performance reasons) by checking the "Inline CSS Styles in HTML Emails" box in the "Sending Defaults" section of the Settings tab: