Custom picklist field with css static resources as names

LetterFormat__c.field-meta.xml

<?xml version="1.0" encoding="UTF-8"?>
<CustomField xmlns="http://soap.sforce.com/2006/04/metadata">
    [...]
    <valueSet>
        <restricted>true</restricted>
        <valueSetDefinition>
            <sorted>false</sorted>
            <value>
                <fullName>DIN_5008_Type_A</fullName>
                <default>true</default>
                <label>DIN 5008 (Type A)</label>
            </value>
            <value>
                <fullName>ANSI_Letter</fullName>
                <default>false</default>
                <label>ANSI Letter</label>
            </value>
        </valueSetDefinition>
    </valueSet>
</CustomField>