docs: Add CSS @font-face implementation snippet for Base Sans

[jadonamite]

Overview

This PR adds a "Web Implementation" section to the README.md under the Fonts header.

Motivation

Currently, the repository directs users to the /fonts directory but lacks instructions on how to actually implement the fonts in a web project. Developers are often left to guess the correct font-weight mapping or write boilerplate CSS from scratch.

The Fix

I have added a ready-to-use CSS snippet that developers can copy and paste. This ensures:

1. Correct Usage: Maps the font files to the standardized Base Sans family name.
2. Accessibility: Includes font-display: swap for better loading performance.
3. Speed: Allows developers to implement the brand kit in seconds.

Checklist

• Validated CSS syntax.
• Verified standard font-family naming (Base Sans).

[cb-heimdall]

🟡 Heimdall Review Status

Requirement	Status	More Info
Reviews	🟡 0/1	Denominator calculation Show calculation 1 if user is bot 0 1 if user is external 0 2 if repo is sensitive 0 From .codeflow.yml 1 Additional review requirements Show calculation Max 0 0 From CODEOWNERS 0 Global minimum 0 Max 1 1 1 if commit is unverified 0 Sum 1

[jadonsunshine]

CSS font implementation guide valuables

[cb-heimdall]

Review Error for jadonsunshine @ 2025-12-29 03:59:16 UTC
User failed mfa authentication, either user does not exist or public email is not set on your github profile. \ see go/mfa-help