/# From https://litmus.com/blog/a-guide-to-bulletproof-buttons-in-email-design
%table{ width: "100%", border: "0", cellspacing:"0", cellpadding:"0" }
  %tr
    %td
      %table{ border:"0", cellspacing:"0", cellpadding:"0", style:"margin: auto" }
        %tr
          %td{ align:"center", style:"border-radius: 5px;", bgcolor:"#0069cc" }
            %a{ href: url, target:"_blank", style:"font-size: 16px; font-family: Helvetica, Arial, sans-serif; color: #ffffff; text-decoration: none; text-decoration: none; border-radius: 5px; padding: 12px 25px; border: 1px solid #0069cc; display: inline-block;" }
              = text