Add Banner to Subpage Headers

I am looking for a skilled web developer to help me add a banner image to the header of all our website subpages. The banner will be the same across all subpages, and I already have the banner image ready for use.

Key Requirements:
- Integrate a pre-existing banner image into the header of all subpages
- Ensure the banner is consistently displayed across different devices and screen sizes
- Maintain the current design and functionality of the website while adding the banner

Ideal Skills and Experience:
- Proficiency in web development and design
- Experience with HTML, CSS, and responsive design
- Attention to detail to ensure seamless integration of the banner
- Good communication skills to understand and implement my requirements effectively

Please reach out if you have the expertise to assist with this project.