Below is a responsive email template.

<!doctype html>
<html>
<head>
<meta charset="utf-8">
<meta name="viewport" content="width=device-width, initial-scale=1.0">
<meta http-equiv="X-UA-Compatible" content="IE=edge">
<title>Responsive Email Template</title>
<!-- CSS Reset -->
<style type="text/css">
html, body {
margin: 0 !important;
padding: 0 !important;
height: 100% !important;
width: 100% !important;
}
* {
-ms-text-size-adjust: 100%;
-webkit-text-size-adjust: 100%;
}
.ExternalClass { width: 100%; }
div[style*="margin: 16px 0"] { margin: 0 !important; }
table, td {
mso-table-lspace: 0pt !important;
mso-table-rspace: 0pt !important;
}
table {
border-spacing: 0 !important;
border-collapse: collapse !important;
table-layout: fixed !important;
margin: 0 auto !important;
}
table table table { table-layout: auto; }
img { -ms-interpolation-mode: bicubic; }
.yshortcuts a { border-bottom: none !important; }
a[x-apple-data-detectors] { color: inherit !important; }
</style>
<style type="text/css">
/* What it does: Hover styles for buttons */
.button-td, .button-a { transition: all 100ms ease-in; }
.button-td:hover, .button-a:hover {
background: #555555 !important;
border-color: #555555 !important;
}
/* Media Queries */
@media screen and (max-width: 600px) {
.email-container { width: 100% !important; }
.fluid, .fluid-centered {
max-width: 100% !important;
height: auto !important;
margin-left: auto !important;
margin-right: auto !important;
}
.fluid-centered {
margin-left: auto !important;
margin-right: auto !important;
}
.stack-column, .stack-column-center {
display: block !important;
width: 100% !important;
max-width: 100% !important;
direction: ltr !important;
}
.stack-column-center { text-align: center !important; }
.center-on-narrow {
text-align: center !important;
display: block !important;
margin-left: auto !important;
margin-right: auto !important;
float: none !important;
}
table.center-on-narrow { display: inline-block !important; }
}
</style>
</head>
<body bgcolor="#e0e0e0" width="100%" style="margin: 0;" yahoo="yahoo">
<table bgcolor="#e0e0e0" cellpadding="0" cellspacing="0" border="0" height="100%" width="100%" style="border-collapse:collapse;">
<tr>
<td><center style="width: 100%;">
<!-- Visually Hidden Preheader Text : BEGIN -->
<div style="display:none;font-size:1px;line-height:1px;max-height:0px;max-width:0px;opacity:0;overflow:hidden;mso-hide:all;font-family: sans-serif;"> (Optional) This text will appear in the inbox preview, but not the email body. </div>
<!-- Visually Hidden Preheader Text : END -->
<table align="center" width="600" class="email-container">
<tr>
<td style="padding: 20px 0; text-align: center"><img src="https://dummyimage.com/200x50" alt="alt_text" border="0"></td>
</tr>
</table>
<table cellspacing="0" cellpadding="0" border="0" align="center" bgcolor="#ffffff" width="600" class="email-container">
<!-- Hero Image, Flush : BEGIN -->
<tr>
<td class="full-width-image"><img src="https://dummyimage.com/600x300" alt="alt_text" border="0" align="center" style="width: 100%; max-width: 600px; height: auto;"></td>
</tr>
<tr>
<td style="padding: 40px; text-align: center; font-family: sans-serif; font-size: 15px; mso-height-rule: exactly; line-height: 20px; color: #555555;"> Maecenas sed ante pellentesque, posuere leo id, eleifend dolor. Class aptent taciti sociosqu ad litora torquent per conubia nostra, per inceptos himenaeos. Praesent laoreet malesuada cursus. Maecenas scelerisque congue eros eu posuere. Praesent in felis ut velit pretium lobortis rhoncus ut erat. <br>
<br>
<!-- Button : Begin -->
<table cellspacing="0" cellpadding="0" border="0" align="center" style="margin: auto">
<tr>
<td style="border-radius: 3px; background: #222222; text-align: center;" class="button-td"><a href="http://www.google.com" style="background: #222222; border: 15px solid #222222; padding: 0 10px;color: #ffffff; font-family: sans-serif; font-size: 13px; line-height: 1.1; text-align: center; text-decoration: none; display: block; border-radius: 3px; font-weight: bold;" class="button-a">
<!--[if mso]> <![endif]-->A Button<!--[if mso]> <![endif]-->
</a></td>
</tr>
</table>
</td>
</tr>
<!-- Background Image with Text -->
<tr>
<td bgcolor="#222222" valign="middle" style="text-align: center; background-position: center center !important; background-size: cover !important;"><!--[if gte mso 9]>
<v:rect xmlns:v="urn:schemas-microsoft-com:vml" fill="true" stroke="false" style="width:600px;height:175px; background-position: center center !important;">
<v:fill type="tile" src="assets/Responsive/Image_600x230.png" color="#222222" />
<v:textbox inset="0,0,0,0">
<![endif]-->
<div>
<table align="center" border="0" cellpadding="0" cellspacing="0" width="100%">
<tr>
<td valign="middle" style="text-align: center; padding: 40px; font-family: sans-serif; font-size: 15px; mso-height-rule: exactly; line-height: 20px; color: #ffffff;"> Maecenas sed ante pellentesque, posuere leo id, eleifend dolor. Class aptent taciti sociosqu ad litora torquent per conubia nostra, per inceptos himenaeos. Praesent laoreet malesuada cursus. Maecenas scelerisque congue eros eu posuere. Praesent in felis ut velit pretium lobortis rhoncus ut erat. </td>
</tr>
</table>
</div>
<!--[if gte mso 9]>
</v:textbox>
</v:rect>
<![endif]--></td>
</tr>
<!-- Two Even Columns-->
<tr>
<td align="center" valign="top" style="padding: 10px;"><table cellspacing="0" cellpadding="0" border="0" width="100%">
<tr>
<td class="stack-column-center"><table cellspacing="0" cellpadding="0" border="0">
<tr>
<td style="padding: 10px; text-align: center"><img src="https://dummyimage.com/270x270" width="270" height="270" alt="alt_text" border="0" class="fluid"></td>
</tr>
<tr>
<td style="font-family: sans-serif; font-size: 15px; mso-height-rule: exactly; line-height: 20px; color: #555555; padding: 0 10px 10px; text-align: left;" class="center-on-narrow"> Maecenas sed ante pellentesque, posuere leo id, eleifend dolor. Class aptent taciti sociosqu ad litora torquent per conubia nostra, per inceptos himenaeos. </td>
</tr>
</table></td>
<td class="stack-column-center"><table cellspacing="0" cellpadding="0" border="0">
<tr>
<td style="padding: 10px; text-align: center"><img src="https://dummyimage.com/270x270" width="270" height="270" alt="alt_text" border="0" class="fluid"></td>
</tr>
<tr>
<td style="font-family: sans-serif; font-size: 15px; mso-height-rule: exactly; line-height: 20px; color: #555555; padding: 0 10px 10px; text-align: left;" class="center-on-narrow"> Maecenas sed ante pellentesque, posuere leo id, eleifend dolor. Class aptent taciti sociosqu ad litora torquent per conubia nostra, per inceptos himenaeos. </td>
</tr>
</table></td>
</tr>
</table></td>
</tr>
</table>
<!-- Email Footer-->
<table align="center" width="600" class="email-container">
<tr>
<td style="padding: 40px 10px;width: 100%;font-size: 12px; font-family: sans-serif; mso-height-rule: exactly; line-height:18px; text-align: center; color: #555555;"><webversion style="color:#cccccc; text-decoration:underline; font-weight: bold;">View as a Web Page</webversion>
<br>
<br>
Company Name<br>
<span class="mobile-link--footer">Adobe Systems Incorporated, 345 Park Avenue</span> <br>
<br>
<unsubscribe style="color:red; text-decoration:underline;">unsubscribe</unsubscribe></td>
</tr>
</table>
</center></td>
</tr>
</table>
</body>
</html>