出于某种原因，当我为表格中的单元格设置宽度时，它不会影响单元格的宽度。仅供参考，我正在为邮件使用内联样式。
<table cellpadding="0" cellspacing="0" width="100%">
<tr>
<td align="center">
<table cellpadding="0" cellspacing="0" width="550" style="width: 100%; max-width: 550px; text-align: center; border: 1px solid #003a4b;">
<tr>
<td style="padding-top: 10px;"><span style="font-family: helvetica, sans-serif; font-size: 37px; font-weight: bold; color: #93d600; border-bottom: 1px solid #003a4b;">Hunters Conference 2017</span></td>
</tr>
<tr>
<td width="80%" style="padding: 20px 0; background-color: blue;"><span style="font-family: helvetica, sans-serif; font-size: 16px; color: #003a4b; background-color: red;">Fyber were honoured to attend and support such a fantastic conference, congratulations to everyone that won a prize on our wheel of fortune!</span></td>
</tr>
<tr>
<td width="80%" style="padding: 0 55px; padding-bottom: 20px;"><span style="font-family: helvetica, sans-serif; font-size: 16px; color: #003a4b;">We hope you all had a great day, we enjoyed catching up with everyone and it was nice to see our clients face to face. </span></td>
</tr>
<!--[if mso]>
<tr>
<td style="padding-bottom: 20px;">
<img src="https://gallery.mailchimp.com/b083c967cd22e35ab4ce75e7a/images/2c3e3b5e-9a9f-4864-a36f-6359b0dd4b75.jpg" alt="Spinning Wheel" width="550" style="width: 100%; max-width: 550px;">
</td>
</tr>
<![endif]-->
<!--[if !mso]><!-- -->
<tr>
<td style="padding-bottom: 20px;">
<img src="https://gallery.mailchimp.com/b083c967cd22e35ab4ce75e7a/images/19e810cd-df47-474b-aa47-3f33bf26922a.gif" alt="Spinning Wheel" width="550" style="width: 100%; max-width: 550px;">
</td>
</tr>
<!--<![endif]-->
</table>
</td>
</tr>
</table>
https://jsfiddle.net/xmbsemje/
最佳答案
td的默认行为是填充表格的宽度，因此，如果每行<td>只有一个<tr>，则无论您做什么，它将始终变为表格的整个宽度。
一种方法是在td内创建一个表，然后将宽度放在表上。同样，在电子邮件中向左和向右填充也无效，因此创建具有定义宽度的表格并将它们居中是最佳选择。
另一种方法是在左右两侧都有间隔单元，以给您填充空间。我按照第一种方法修改了您的代码（只是带有蓝色/红色和白色背景的文本单元格）。
请注意：我并没有修复您的所有代码，只需更改几下即可入门
<table cellpadding="0" cellspacing="0" width="100%">
<tr>
<td align="center">
<table cellpadding="0" cellspacing="0" width="550" style="width: 100%; max-width: 550px; text-align: center; border: 1px solid #003a4b;">
<tr>
<td style="padding-top: 10px;"><span style="font-family: helvetica, sans-serif; font-size: 37px; font-weight: bold; color: #93d600; border-bottom: 1px solid #003a4b;">Hunters Conference 2017</span></td>
</tr>
<tr>
<td align="center" style="padding: 20px 0; background-color: blue;">
<table border="0" cellpadding="0" cellspacing="0" style="width:80%;">
<tr>
<td align="left"><span style="font-family: helvetica, sans-serif; font-size: 16px; color: #003a4b; background-color: red;">Fyber were honoured to attend and support such a fantastic conference, congratulations to everyone that won a prize on our wheel of fortune!</span></td>
</tr>
</table>
</td>
</tr>
<tr>
<td align="center" style="padding: 20px 0;">
<table border="0" cellpadding="0" cellspacing="0" style="width:80%;">
<tr>
<td align="left"><span style="font-family: helvetica, sans-serif; font-size: 16px; color: #003a4b;">We hope you all had a great day, we enjoyed catching up with everyone and it was nice to see our clients face to face. </span></td>
</tr>
</table>
</td>
</tr>
<!--[if mso]>
<tr>
<td style="padding-bottom: 20px;">
<img src="https://gallery.mailchimp.com/b083c967cd22e35ab4ce75e7a/images/2c3e3b5e-9a9f-4864-a36f-6359b0dd4b75.jpg" alt="Spinning Wheel" width="550" style="width: 100%; max-width: 550px;">
</td>
</tr>
<![endif]-->
<!--[if !mso]><!-- -->
<tr>
<td style="padding-bottom: 20px;">
<img src="https://gallery.mailchimp.com/b083c967cd22e35ab4ce75e7a/images/19e810cd-df47-474b-aa47-3f33bf26922a.gif" alt="Spinning Wheel" width="550" style="width: 100%; max-width: 550px;">
</td>
</tr>
<!--<![endif]-->
</table>
</td>
</tr>
</table>关于html - 宽度不适用于表格单元格，我们在Stack Overflow上找到一个类似的问题：https://stackoverflow.com/questions/43275513/