Build accessible user interfaces using semantic HTML, proper ARIA attributes, keyboard navigation, color contrast, and screen reader compatibility. Use this skill when creating or modifying frontend components, HTML templates, React/Vue/Svelte components, forms, interactive elements, navigation menus, modals, or any UI elements. Apply when working with HTML files, JSX/TSX components, template files, ensuring keyboard accessibility, implementing focus management, adding alt text to images, creating form labels, testing with screen readers, managing ARIA attributes, maintaining color contrast ratios, or building heading hierarchies. Use for any task involving UI accessibility compliance, WCAG standards, or inclusive design patterns.