CSS Overflow Module Level 3

CSS Overflow Module Level 3 introduces more precise ways to manage content that exceeds an element's boundaries, building upon previous standards with new properties and values. A primary addition is the overflow: clip value, which differs from hidden by preventing all scrolling, including programmatic adjustments via JavaScript. To accompany this, the overflow-clip-margin property allows developers to extend the clipping area beyond the padding box, ensuring visual effects like shadows are not abruptly cut off. The module also standardizes logical properties like overflow-inline and overflow-block to better support diverse writing modes and vertical layouts. Furthermore, the scrollbar-gutter property is introduced to prevent layout shifts by reserving space for scrollbars regardless of their visibility. These updates aim to resolve long-standing interoperability issues across browsers while improving the accessibility and visual control of web layouts.