Try these as a starting point:
Status:
If([Expiration Date] < Today(), "Expired", ToDays([Expiration Date] - Today()) <= 90, "Renew", "Ok")
Rich Text field:
var text Danger = "<a style=\" text-decoration: none; background: #FF0000; border-radius: 5px; color: #fff; display: inline-block; width: 75px; text-align: center; padding: 8px 5px; font: normal 700 14px/1 \"Calibri\", sans-serif; text-shadow: none; \">Exipired</a>";
var text Warning = "<a style=\" text-decoration: none; background: #FFFF00; border-radius: 5px; color: #000; display: inline-block; width: 75px; text-align: center; padding: 8px 5px; font: normal 700 14px/1 \"Calibri\", sans-serif; text-shadow: none; \">Renew</a>";
var text Success = "<a style=\" text-decoration: none; background: #008000; border-radius: 5px; color: #fff; display: inline-block; width: 75px; text-align: center; padding: 8px 5px; font: normal 700 14px/1 \"Calibri\", sans-serif; text-shadow: none; \">Ok</a>";
If([Status] = "Expired", $Danger, [Status] = "Renew", $Warning, $Success)
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Paul Peterson
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