Senior HTML/CSS Frontend Engineer - AI Training (Remote)

Prolific Academic Ltd; United States; Remote; USD 69,000 - 101,000; Full time

Job summary

Prolific is seeking Senior HTML/CSS Developers to join our Expert Network in the UK to help train and evaluate AI models. You may be invited to join Prolific as a participant and paid for tasks that involve implementing high-quality frontend code.

Core work includes reviewing AI-generated HTML/CSS for accuracy, semantics, and cross-browser compatibility, and providing structured feedback to improve reasoning and design systems. Flexible hours and remote work are available.

Qualifications

• BSc or higher in Computer Science, Software Engineering, Web Development, or related field.
• Senior Frontend Developer/UI Engineer with HTML/CSS focus.
• Ability to build complex, responsive layouts and components without relying on frameworks.
• Deep knowledge of CSS cascade, specificity, box model, Flexbox, Grid, WCAG, and cross-browser compatibility.
• Commit to clean, semantic markup and maintainable CSS (BEM, design tokens, modern CSS).

Responsibilities

• Evaluate AI-generated HTML/CSS for accuracy and semantic structure.
• Audit AI explanations for layout solutions and styling approaches.
• Render and test model-generated markup in appropriate environments.
• Identify inaccessible markup, inefficient selectors, and deprecated CSS properties.
• Provide feedback on responsive design, component architecture, and design system implementation.

Skills

HTML5

CSS3

Tailwind CSS

SASS/SCSS

CSS Modules

DevTools

Axe

Lighthouse

Education

BSc or higher in CS/SE/Web Development

Tools

Browser DevTools

Axe

Lighthouse

Cross-browser testing

Job description

Prolific is seeking Senior HTML/CSS Developers to join our Expert Network in the UK to help train and evaluate AI models. You may be invited to join Prolific as a participant and paid for tasks that involve implementing high-quality frontend code.

Core work includes reviewing AI-generated HTML/CSS for accuracy, semantics, and cross-browser compatibility, and providing structured feedback to improve reasoning and design systems. Flexible hours and remote work are available.