Conditional formatting on a list

darrenm88 

You can achieve this by setting additionalRowClass in view formatting JSON.

Example:

{
  "$schema": "https://developer.microsoft.com/json-schemas/sp/view-formatting.schema.json",
   "additionalRowClass": "=if([$DueDate] <= @now, 'sp-field-severity--severeWarning', '')"
}

Sample Output:

You can find more information about view formatting at: Use view formatting to customize SharePoint 

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