How to write condition for SCSS/SASS import?

Question

Sass

Example
There are two files: "styles.scss" and "_if.scss"
The file "_if.scss" contains the following code

.foo {
    background: red
}
.bar {
    background: url(bar.png)
}

In the same place most likely it is necessary to set some condition.
If it ==true, then when "_if.scss" is connected to "styles.scss", the latter will contain only styles with background: url*
Is it possible to do this?
PS By connection is meant @import "if";inside styles.scss