I'll modify the code to change the "NEXT" block letters to "ATLAS". Here's the updated version:

These changes will replace the "NEXT" block letters with "ATLAS". The new letters "A", "L", and "S" have been added to the getLetterShape function, and the positioning has been adjusted to accommodate the new word. The scene should now display "ATLAS" instead of "NEXT" using the same block style and animation.

I'll create a more refined 3D logo for "ATLAS" with a sleeker font, shiny gold material, and add some particle effects for smoke and fireworks. This will require some significant changes to our scene, including the use of 3D text and particle systems. Let's update our code:

This new version creates a more sophisticated and visually appealing 3D logo for "ATLAS". Here's a breakdown of the changes:

1. We're using Text3D from @react-three/drei to create a 3D text object with a sleek, modern font (Geist Bold).
2. The text material is now a shiny gold color with high metalness and low roughness, giving it a polished look.
3. We've added a Sparkles component around the text to create a shimmering effect, simulating the "silvery wisps" you mentioned.
4. A custom ParticleSystem component has been added to create rising particles, which simulate smoke and fireworks.
5. The logo now rotates slowly, adding dynamic movement to the scene.
6. The environment has been changed to a city preset, which will reflect on the shiny gold material of the text.
7. The camera position has been adjusted for a better view of the new logo.

This new design should give you a more corporate and polished look, with the shiny gold material for the text and particle effects to add dynamic elements that resemble smoke and fireworks.

To make this work, you'll need to ensure you have the Geist Bold font file (Geist_Bold.json) in your /public/fonts/ directory. If you don't have this specific font, you can replace it with another .json font file and update the font prop in the Text3D component accordingly.