Cross-browser compatibility remains a significant challenge in web development due to inconsistencies in how different browser engines render CSS code. Developers often face issues with layouts appearing differently across browsers such as Chrome, Safari, Firefox, Edge, Opera, and Internet Explorer, due to each browser's unique rendering engine and support for specific CSS properties. To address these challenges, creating browser-specific CSS can help ensure consistent user experiences across different platforms. The article discusses various techniques for writing browser-specific CSS for each major browser, emphasizing the importance of validation and testing to ensure compatibility. It highlights the need for tools like validators, CSS frameworks, and cross-browser testing platforms such as LambdaTest to streamline the process and ensure that web applications render correctly across various devices and browsers. By understanding the intricacies of browser-specific CSS, developers can better prepare their web applications for diverse user environments.