Auto formatting of the content_url

Auto formatting of the content_url

I'm currently using the API to create campaigns with the /api/v1.1/createCampaign endpoint. As requested, I'm providing a content_url that contains the full HTML code of my email. It is fully responsive, working, and designed to receive some Ads. I was first using Mailchimp and was also providing the full HTML without any issue.

Since I have migrated to Zoho Campaigns, my emails have been reformatted when parsed, and creates a lot of issues.

Here are some of the changes Zoho Campaigns make to my emails while parsed :
  1. Wrapping the content into another table of 600px width. This means I now have a white background instead of gray, and we cannot sell anymore ads that goes around the template on desktops. Here's an example :
  2. Adding some global CSS style. This extra CSS is including some responsive elements that might create some unwanted behaviours, like setting the default line-height to 1.7 on every element.

Is there a way to deactivate this auto formatting? I have tried several things to get around the issue, but nothing worked.