Hello, Steven Tay,
Please change the code to:
.woocommerce-account .wcfmmp_become_vendor_link a, .woocommerce-form-register .wcfmmp_become_vendor_link a { font-size: 20px !important; color: #fff !important; } .woocommerce-account .wcfmmp_become_vendor_link, .woocommerce-form-register .wcfmmp_become_vendor_link { background-color: #000 !important; border: 1px solid #000 !important; border-radius: 20px !important; padding-top: 5px !important; padding-bottom: 5px !important; text-align: center !important; }
Kind Regards, 8theme team
