Modern CSS techniques have evolved to solve common problems that developers face while designing web pages. The article discusses 12 modern CSS techniques for overcoming older problems such as browser compatibility issues, grid system alternatives, typography scaling, and more. These techniques use advanced CSS properties like `grid-template-columns`, `flex-direction`, `box-shadow`, and `linear-gradient` to create responsive and accessible web designs. The techniques also cover topics like styling radio buttons, maintaining footer positions, animating images, and drawing shapes using CSS. By mastering these modern CSS techniques, developers can improve the overall user experience of their websites and applications.