HTML/CSS - Senior Developers - AI Training - London, UK

prolificacademicltd; United States; Remote; USD 34,000 - 55,000; Full time

Benefits offered by this job

Flexible, remote participation

Hourly task-based pay up to $40

Job summary

Prolific Academic Ltd is seeking a senior frontend specialist to assess and improve AI-generated frontend work across responsiveness, accessibility, and design systems. You will review markup, styles, and explanations, and provide structured feedback on how models handle frontend challenges.

Responsibilities include auditing code for semantics and maintainability, validating layout choices, rendering across browsers, and offering actionable improvements.

Qualifications

• Bachelor's degree or higher in a technical field such as computer science, software engineering or web development.
• Senior frontend or UI engineer experience focused on HTML and CSS.
• Ability to build complex, responsive layouts without frameworks or libraries.
• Strong knowledge of CSS fundamentals, Flexbox, Grid, WCAG accessibility, and browser compatibility.
• High standards for semantic HTML and maintainable CSS, including familiarity with BEM and design tokens.

Responsibilities

• Review generated markup and styles for correctness, semantics, and maintainability.
• Check the technical reasoning behind layout and styling choices.
• Render code and inspect visual output and cross-browser behaviour.
• Flag accessibility issues, inefficient selectors, and deprecated attributes.
• Provide feedback on responsive design, component structure, and design system implementation.

Skills

Semantic HTML

Maintainable CSS

Flexbox

Grid

WCAG Accessibility

Cross-browser compatibility

BEM

Design tokens

Modern CSS

Education

Bachelor's degree in CS/SE/Web Development

Tools

Tailwind CSS

Sass/SCSS

CSS Modules

Browser DevTools

Job description

Role overview

Use your senior HTML and CSS expertise to help assess and improve AI-generated frontend work. The work involves reviewing code and its explanations, checking rendered results, and giving structured feedback on how models handle responsive layouts, accessibility, and design systems. Tasks are paid and may require an uninterrupted hour; an initial skills assessment takes about 10-15 minutes.

Responsibilities

• Review generated markup and styles for correctness, semantics, and maintainability.
• Check the technical reasoning behind proposed layout and styling choices.
• Render code and inspect its visual output and cross-browser behaviour.
• Flag accessibility issues, inefficient selectors, deprecated attributes, and invalid CSS.
• Provide clear feedback on responsive design, component structure, and design system implementation.

Requirements

• A bachelor's degree or higher in computer science, software engineering, web development, or a related technical field.
• Professional experience as a senior frontend developer or UI engineer focused on HTML and CSS.
• Ability to build complex, responsive layouts and components without relying on frameworks or libraries.
• Strong knowledge of CSS fundamentals, Flexbox, Grid, WCAG accessibility, and browser compatibility.
• High standards for semantic HTML and maintainable CSS, including familiarity with BEM, design tokens, and modern CSS.

Nice to have

• Experience with HTML5 and modern CSS features such as custom properties, animations, and contemporary layout systems.
• Familiarity with Tailwind CSS, Sass/SCSS, CSS Modules, and component-based design systems.
• Proficiency with browser developer tools, accessibility audits, and cross-browser testing.

Benefits and work setup

• Flexible, remote participation, subject to available tasks.
• Task rates may reach $40 per hour depending on skills and experience; this is not a guaranteed rate or workload.