Minor UI and content inconsistencies on DeepChem.io

## Description
I noticed a few small but valid issues on the DeepChem.io website that could improve the consistency and overall user experience. Listing them below for clarity:

1. **Footer:**
- Update copyright year from `2022` → `2025`.
- Change “Twitter” text to “X”.

2. **Homepage – "Used By Scientific Leaders" carousel:**
- When clicking the right arrow the *first time*, the image moves left (opposite direction).
After that, it behaves normally.

3. **About page – "Companies & Universities Developing DeepChem" carousel:**
- The carousel moves unpredictably — clicking the right arrow sometimes skips or jumps slides irregularly.

4. **Tutorials section:**
- The “Back to Top” button appears only in this section. Either make it appear across all sections for uniformity or remove it entirely.

5. **Logo:**
- The DeepChem GitHub repository now uses an updated logo, but the website still displays the older one. Suggest updating the site to match the latest logo.

### Suggested Fix
If these issues look valid, I would be happy to open a PR addressing them.

### Additional Context
These are small front-end and content-level improvements; no major layout changes.
Not sure if this repo is still actively maintained, so please confirm if it's okay for me to proceed with a PR.