TL;DR The PADDING + BORDER-BASED BUTTON

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          <td align="center" style="border-radius: 3px;" bgcolor="#e9703e"><a href="https://litmus.com" target="_blank" style="font-size: 16px; font-family: Helvetica, Arial, sans-serif; color: #ffffff; text-decoration: none; text-decoration: none;border-radius: 3px; padding: 12px 18px; border: 1px solid #e9703e; display: inline-block;">I am a button →</a></td>
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