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Sarah Chima
Sarah Chima

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Using SASS partials

Stylesheets grow large overtime. The more they grow, the more difficult it is to maintain them. It only makes sense to break large stylesheets into smaller chunks. Partials in Sass helps us to break our files into small files without affecting performance.

A partial is simply an Sass file preceded by an underscore. An example is _name-of-file.scss. The underscore tells Sass that the file is a partial and that it should not be compiled to CSS. This partial can then be imported into another file that will be compiled to CSS. Depending on the way you want to structure your Sass project, a partial can contain all variables used in your project, functions or mixins or it might be for specific pages or components of your pages.

A partial is imported using the @import directive. The @import directive is also available in CSS. However, they are different. Anytime an import statement is used in CSS, a http request is made to the server. This increases the number of resources that is requested for and negatively affects the performance of a web page. Sass does not do that. Rather, it takes the file that you want to import and combines it with the file you're importing into so you can serve a single CSS file to the web browser. So this does not affect the performance. A file where partials are imported to is called a manifest file.

Let's use an imaginary directory to explain this.

    |-- application.scss    // Sass manifest file
    |-- _reset.sass         // Partials
    |-- _variables.scss             |
    |-- _functions.scss             |
    |-- _mixins.scss                |
    |-- _base.scss                  |
    |-- _buttons.scss               |
    |-- _forms.sass                 |
    |-- _modules.sass               |
    |-- _theme.sass 
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In the directory, you can see the partials and the manifest file where all the partials will be imported into. In the manifest file you import the partials as shown below.


    @import "reset";
    @import "variables";
    @import "functions";
    @import "mixins";
    @import "base";
    @import "buttons";

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Notice that the .scss extension was not added. This is because Sass is smart enough to figure that it out.
All files do not have to be in the same folder though. You can arrange your files in folders and then import appropriately. Using folders makes your files even more organized. Here's an example.

    |– base/ 
    |   |– _reset.scss       # Reset/normalize 
    |   |– _typography.scss  # Typography rules 
    |   ...                  # etc
    |– components/ 
    |   |– _buttons.scss     # Buttons 
    |   |– _navigation.scss  # Navigation
    |   |– _dropdown.scss    # Dropdown  
    |   ...                  # etc 
    main.scss                #manifest file
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These files can then be imported in the main.scss file.


    /* base */
    @import "base/reset";
    @import "base/typography";

    /* components */
    @import "components/buttons";
    @import "components/nav";
    @import "components/dropdown";
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Partials greatly helps us to organize our CSS files. Having an architecture for your project makes it much easier to break your CSS file into partial files. This leads to better maintenance and management of your CSS files.

What tips have you found helpful in using partials?

Any addition or question? Leave a comment.

Thank you for reading. :)

Top comments (12)

gopalkumar315 profile image
Gopal Kumar • Edited

Great job, very nice article, it cleared the main intention of scss over css that how smartly we can work with css using scss. Can you elaborate what are partials, actually i know partials are little snippets of html or css code but i need more definition. It would be pleasure if you could explain partials.

brunoslash76 profile image
Bruno de Moraes

Awesome :) thank you very much for your objective and great article. Happy codding

niorad profile image
Antonio Radovcic

You don't need to import them again, if they were imported in the main-file at an earlier time. Importing is really just like copypasting the file-contents into the main-file.

auxiliaryjoel profile image

when importing files from other folders, is there a way to import multiple files from within a folder without having to specify each files name?

honsa profile image

You can do that by writing an index file

qwezii profile image


1) Can we use @use instead?
2) What is the difference between @use and @import?


prashantandani profile image
Prashant Andani

You can use @use to access specific value/variable instead of the whole file being imported

dapseen profile image
Adedapo ajuwon

Good read..

Partial helps me to resume my style in other projects, which is awesome.

robinjohnmike profile image
J.M Robin

How do you determine if something is a component or not? I just started learning sass and I'm having trouble deciding if something should be a component or not. Thanks.

dapseen profile image
Adedapo ajuwon

It's like writing a function in programming language, i divide my components into bit based on the task each is performing.

Think of component as a block of Style that can perform a particular task and also be repeated in your stylesheet
e.g button, navigation, variables,etc, they can be repeated in your present project and other upcoming projects too.