Team Collaboration SharePoint Site

I need a SharePoint site designed specifically for team collaboration among employees. The primary content on this site will be internal news and announcements.

Key requirements:
- User-friendly interface for easy navigation
- Sections dedicated to internal news and announcements
- Access controls to ensure information security
- Mobile-friendly design

Ideal skills:
- Proficiency in SharePoint development
- Experience in designing collaboration-focused sites
- Strong understanding of access control and security features
- Good design sense for a clean, professional look

Please provide examples of relevant past work.