If a browser does not support a feature, what happens to the styles inside a @supports block?

• A. They apply normally
• B. They override all other rules
• C. They cause errors
• D. They do not apply

Answer: (D)

The key idea is that @supports is a conditional block that only applies when the browser supports the tested feature. If the feature isn’t supported, the declarations inside that block are simply ignored and do not take effect. This behavior lets you provide enhancements for capable browsers without breaking older ones. The rest of the stylesheet continues to apply as normal, and there’s no error or override caused by this ignored block. If the feature is supported, the declarations inside would apply, enabling the enhanced styling.