I have 13 column in my one2many field and I can't reduce cause of requirement. The problem is my many2one column is very less space. When I remove some column , many2one field take perfect column width.But I can't reduce. How can I do that? I try to write css class for my tree view but not working.In image, I can only see Ac text but the really name is Account.
<page string="Yearly Budget">
<field name="budget_yearly_line">
<tree string="Yearly" editable="buttom" class="custom_class">
<field name="account_id"/>
<field name="jan"/>
<field name="feb"/>
<field name="march"/>
<field name="april"/>
<field name="may"/>
<field name="june"/>
<field name="july"/>
<field name="auguest"/>
<field name="sep"/>
<field name="october"/>
<field name="november"/>
<field name="dec"/>
<field name="amount"/>
</tree>
</field>
<group class="oe_subtotal_footer oe_right">
<field name="amount_untaxed"/>
</group>
</page>