Sass TutorialSass @extendIntroduction to Sass ExtendSass @extendSass @extend is a way to inherit styles from another class or placeholder selector. When you use @extend, you can avoid duplicating styles and keep your code DRY (Don't Repeat Yourself).To use @extend, you first define a class or placeholder selector that you want to inherit styles from, and then you use @extend to inherit those styles.As an example:// Define a base button style.btn { padding: 10px; border-radius: 5px; border: 1px solid #ccc; background-color: #fff;}// Define a special button style that inherits from the base button style.btn-special { @extend .btn; color: #fff; background-color: #f00;}In this exampleThe .btn-special class inherits all the styles from the .btn class, including the padding, border-radius, border, and background-color.The @extend directive is used to inherit these styles.You can also use @extend with placeholder selectors, which are defined using the % symbol instead of the . symbol.As an example:// Define a placeholder selector for button styles%btn { padding: 10px; border-radius: 5px; border: 1px solid #ccc; background-color: #fff;}// Define a special button style that inherits from the button placeholder.btn-special { @extend %btn; color: #fff; background-color: #f00;}In this example:The %btn placeholder selector is defined with the same styles as the .btn class.The .btn-special class then inherits these styles using @extend %btn.When you use @extend, Sass generates CSS that combines the styles from both selectors. This can result in more efficient CSS, as it avoids duplicating styles.