If want more space, use this theme
Enhance your Odoo experience with this completely rewritten backend theme for Odoo 11.
If you like blue,try this backend theme
Customizable Backend Theme Based on Material Design
If you a bored,try this theme
If you like colors,buy this theme
Odoo 11.0 Community Backend Theme (based on Openworx Theme)
Enterprise feel on Odoo Community
Odoo 11.0 community backend theme