As CSS approaches its 30th anniversary, it continues to advance with new features such as cascade layers, subgrids, and container queries, enhancing flexibility and responsiveness in web design. Cascade layers allow developers to add and control additional layers in the cascade, avoiding over-reliance on the "!important" rule and enabling more structured styling. Subgrids simplify aligning nested grids by allowing child grid containers to inherit the grid settings from their parent, a feature currently supported only by Firefox. Container queries, still under development, promise to enable components to adjust their styles based on the dimensions of their parent elements rather than the viewport, facilitating more robust responsive design. These advancements exemplify CSS's ongoing evolution to meet the demands of modern web development, while tools like LogRocket provide solutions for monitoring frontend performance and debugging.