Hi, 
You Don't need to use css,Just change the field name from 
list_price  to next field that is  taxes_id and change position to 
“before”.
Here is the Updated XML of the code this will fix Your style
<?xml version="1.0" encoding="utf-8"?>
<odoo>
    <record id="inherited_model_view_form" model="ir.ui.view">
        <field name="name">res.partner.form</field>
        <field name="model">product.template</field>
        <field name="inherit_id" ref="product.product_template_only_form_view"/>
        <field name="arch" type="xml">
            <xpath expr="//field[@name='taxes_id']" position="before">
                        <field name="total_price" string="Total Price" />
            </xpath>
        </field>
    </record>

Hope it helps