Create white-background footer variant

[bhushan-ebi]

As discussed in the meeting on 23rd Jan:

• Create a modular variant with white background option

[Adedoyinebi]

From the discussion, we would be exploring light background to show partnership for both the modular and light weight variants. The mockups will be addressed as part of the iteration tasks:

• Design lightweight EBI footer mockups #2356
• Design modular EBI footer variants #2357

This task will be used to consolidate both approaches