Answer
CSS feature queries use @supports to test whether a user agent supports a declaration or selector. • A true condition applies the nested rules. • Conditions can use not, and, and or. • Feature queries test syntax support, not whether a feature is bug-free.
💡 Simple Example
@supports (display: grid) {
.layout { display: grid; }
}
⚡ Quick Revision
@supports conditionally applies CSS when the tested feature is recognized.