Drupal Belgrade Theme Header Customization

I need a skilled front-end Drupal developer to customize the header of my Belgrade theme on the frontpage.

Specific Tasks:
- Implement a responsive background image
- Position and style a custom content block (which will contain text and a search form) within the header area
- Ensure all modifications are compatible with the existing Belgrade theme structure for future upgrades

Technical Skills Required:
- Proven experience with the Drupal (Belgrade) theme
- Proficiency in Twig templating
- Strong CSS/SCSS styling capabilities
- Expertise in implementing responsive design

Final Deliverables:
- Modified header with integrated custom elements
- Complete CSS implementation for styling
- Thorough documentation of all changes
- Cross-browser and responsive testing (specifically on Chrome, Firefox, and Mobile)

Your ability to keep the upgradeability intact with the existing Belgrade theme structure is crucial. Please include in your proposal any Drupal front end projects you've completed in the past.
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