Creating custom error classes allows you to handle different error types distinctly and add application-specific context to errors. As the creator of CoreUI with over 25 years of JavaScript development experience, I’ve built custom error hierarchies for complex enterprise applications. The most effective solution is to extend the built-in Error class to create custom error types with additional properties. This approach enables precise error handling and better debugging with domain-specific error information.

Removing CSS classes from elements dynamically enables state changes, interactive styling, and responsive design through JavaScript manipulation. As the creator of CoreUI, a widely used open-source UI library, I’ve implemented dynamic class removal in thousands of interactive components for modal closures, active states, and UI transitions. From my expertise, the most effective approach is using the classList.remove() method for safe and reliable class management. This method provides clean class removal without affecting other classes and handles non-existent class removal gracefully.

Adding CSS classes to elements dynamically enables interactive styling, state changes, and responsive design through JavaScript manipulation. As the creator of CoreUI, a widely used open-source UI library, I’ve implemented dynamic class manipulation in countless interactive components for state management and visual feedback. From my expertise, the most effective approach is using the classList.add() method for clean and reliable class management. This method provides safe class addition without affecting existing classes and handles duplicate prevention automatically.