for...in...loop - CSS

CSS styles can be applied to HTML elements using selectors. However, when we have many elements to style, writing CSS styles for each individual element can be repetitive and time-consuming. Here, the for...in...loop in CSS comes into play.

The for...in...loop is a loop statement that iterates over the properties of an object. In CSS, we can use this loop to apply styles to a group of elements that share a common attribute or class.

Syntax

for (variable in object) {
  // code to be executed
}

• variable: Required. A variable to hold the name of each property as the loop iterates through the object.
• object: Required. An object whose properties will be iterated over using the loop.

Example

Say we have a group of <h2> headings that share a common class, my-heading. To apply styles to all of these headings, we can use the for...in...loop in CSS like this:

:root {
  --headings: 5; /* Define the number of headings */
}
 
@for $i from 1 through var(--headings) {
  h2.my-heading:nth-of-type(#{$i}) {
    font-size: calc(1em + (#{$i} - 1) * 0.2em); /* Increase font-size with each heading */
    color: blue; /* Set a color */
  }
}

In this example, we define the number of headings using the CSS variable --headings. We then use the for...in...loop to iterate over each heading using the nth-of-type() selector and apply styles using CSS properties.

Conclusion

The for...in...loop in CSS can save us a lot of time and effort when we need to apply styles to a group of elements. By iterating over the properties of an object, we can apply styles dynamically to any number of elements that share a common attribute or class.