Hello Mahmet,

Description

When defining a field style, if you leave the Value field blank, the style is presented only in the form view instead of both the form view and list view.

Steps to Reproduce

1. Log in to a demo instance.
2. Navigate to System UI > Field Styles and click New.
3. Create two new styles with the following values, and click Submit after creating each one.Style 1:
   Table: incident
   Field name: number
   Value: javascript:true
   Style: background-color:purpleStyle 2:
   Table: incident
   Field name: caller
   Value: <Leave blank>
   Style: background-color:purple
4. Check the fields in the list view and the form view and note that the list view style is applied only when the Value field is populated.

Workaround

Within the field's Style text box, insert a simple default line of CSS code like the following example:

text-align: left

Please Refer :ServiceNow KB: Field styles are not displayed in list view when the Value field is left empty (KB058...