Email Tracking

We are wanting to add the code shown below to track the emails. However, the company that provided the code told us that we need to "switch off CSS inlining" in Marketo prior to adding this code. This is because Marketo is removing most of the code and leaving only the last line. Please advise on how to "switch off CSS inlining" and make this work.

Below is the code we are trying to add to our emails:

<style>@media print{ #_t { background-image: url('https://pwej2oqz.emltrk.com/pwej2oqz?p&d={{lead.Email Address:default=noemail}}');}} div.OutlookMessageHeader {background-image:url('https://pwej2oqz.emltrk.com/pwej2oqz?f&d={{lead.Email Address:default=noemail}}')} table.moz-email-headers-table {background-image:url('https://pwej2oqz.emltrk.com/pwej2oqz?f&d={{lead.Email Address:default=noemail}}')} blockquote #_t {background-image:url('https://pwej2oqz.emltrk.com/pwej2oqz?f&d={{lead.Email Address:default=noemail}}')} #MailContainerBody #_t {background-image:url('https://pwej2oqz.emltrk.com/pwej2oqz?f&d={{lead.Email Address:default=noemail}}')}</style><div id="_t"></div>
<img src="https://pwej2oqz.emltrk.com/pwej2oqz?d={{lead.Email Address:default=noemail}}" width="1" height="1" border="0" />