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Four options set as equal hairline rows, including less often and unsubscribe. Send it before a quiet address goes on a suppression list.

680px

About this email

Table layout with ghost tables for Outlook. Columns are tables inside Outlook-only conditional comments, so Word's engine gets the widths it needs and everyone else gets the responsive version.
Background images with VML fill. Background images fall back to a VML rectangle in Outlook instead of disappearing.
Dark-mode meta. color-scheme and supported-color-schemes tell Apple Mail and Outlook how the email expects to be treated in dark mode.
Preheader. The preview text is in the HTML, hidden from the body, so the inbox shows what you wrote instead of the first line of the footer.
Mobile stacking. Columns stack under 600px with a media query, and stay side by side where media queries are ignored.
Inline styles. Every style that matters is on the element, because Gmail strips most of the head and some clients drop it entirely.
Exact line heights in Outlook. mso-line-height-rule: exactly keeps spacers and text from drifting in Outlook for Windows.
Outlook DPI fix. The OfficeDocumentSettings block stops Outlook from scaling images on high-DPI Windows displays.
Presentation tables. Layout tables carry role="presentation" so screen readers read the content, not the grid.