Comprehensive UI Design Help

I'm in need of a talented UI designer who can assist me with creating an appealing and user-friendly interface for my project. The design will need to cater for Web, Mobile, and Desktop platforms, so experience with cross-platform UI design is a must.

Key Responsibilities:
- Collaborate with me to create UI design from scratch
- Apply principles of Human-Computer Interaction (HCI) to enhance usability
- Implement design using HTML and CSS

Ideal Skills and Experience:
- Proven experience in UI design for Web, Mobile and Desktop
- Strong understanding of HCI principles
- Proficient in HTML and CSS
- Experience with cross-platform UI design