I would create a list view with datasource "microflow” to retrieve the employees with a birthday in the coming 10 days. On the employee object I would add a boolean attribute “isBirthdayToday”. While retrieving the list with employees i would also check if the birthday is today. If yes then I would set the “isBirthdayToday” on true and use this attribute with conditinal visibility on your page. Put the attribute “employee.name” 2 times in your page, The first is only visible when the “isBirtdayToday” attribute is true and use some styling to give it a different background colour, the other one is only visible when the “isBirthdayToday” attribute is false and you don't use any styling on this so he background will appear normal.
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