To work in Advanced CSS in a style:
  1. Navigate to onMessage.
  2. Select Website > Main Site (your site name).
  3. Click Styles.
  4. Locate your style and click Edit
  5. Select the area of your style you're working in.
  6. In the lower left, select CSS: Advanced.
  7. Add/Edit the CSS field.
  8. Click Save in the lower right corner.
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