Create 12-15 Modern Posters

I'm looking for a designer to create 12-15 modern and clean posters for my website. The posters will be used for various purposes, not limited to advertising, providing information, or promoting events.

Requirements:
- Modern and clean design
- Adherence to my specific brand colors
- Experience in digital poster design
- Ability to deliver high-quality, web-optimized images

Ideal Skills:
- Graphic design expertise
- Proficiency in design software (e.g., Adobe Photoshop, Illustrator)
- Strong portfolio showcasing similar work
- Attention to detail and ability to follow brand guidelines

Please provide samples of previous work and an estimate of the time required for completion.