Update CSS library design tokens for base, root font and default font

[caw310]

Description

Update CSS library design tokens for base and root font. Base font design token will be changed to root font design token. Root font design token will be set to 16px and default font design token will be 16.96

Details

Adding design tokens: Change base font design token and add default font design token Change the base font design token to root font design token. Set the root font design token 16px. Add a default font design token for 16.96

Tasks

• [ ] Add root font and default font design tokens to the CSS library

Acceptance Criteria

• [ ] New design tokens have been added to the CSS library

[caw310]

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