Cosmetic change

README.md

 4. Scan the cartoon below.
 5. Enjoy! :wink:
 
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 > **Guidelines for WebAR:**
 > - WebGL2 and WebAssembly are required. Use a [compatible browser](#browser-compatibility).
 > - Don't move the camera too quickly - it produces motion blur.
 > - The physical environment should be properly illuminated.
 > - Avoid low-quality cameras (cameras of common smartphones are OK).
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 | Cartoon |   |
 | - | - |