If you have coding knowledge and want to customize your site beyond the adjustments you can make in the Style Editor, you can add CSS code using the CSS Editor.
Note: Adding or modifying code within your site is an ADVANCED modification and we recommend you have coding knowledge before attempting this type of modification. Squarespace Customer Care CANNOT offer help for troubleshooting code or provide you with code to use within your Squarespace site. Custom CSS should be used for specific adjustments, as mentioned in our guide here.

Step 1 - Access the CSS Editor[top]

Click the Preview icon within your Site Manager to access the Preview of your site.
Once you are previewing your site, click the Paintbrush icon to open the Style Editor.
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With the Style Editor open, you can click the CSS button at the bottom to open the CSS Editor.
You will be prompted with a warning that modifying CSS could break your design and you will need to confirm that you understand before you can open the CSS Editor by clicking the Confirm button.
After confirming you understand the warning, the CSS Editor will open and you can begin adding or modifying code.

Step 2 - Add CSS Code[top]

Now that the CSS Editor is open you can begin writing your code. You will see line numbers created as you add more code in the editor to help you easily reference pieces of your CSS code. Syntax errors will be displayed at the bottom in red.

Step 3 - Upload Files (Optional)[top]

You may wish to use custom images or font files in your custom CSS code. The CSS Editor offers its own file upload area where you may upload these assets for use with your custom code. To access this area, first click the Custom Files button to the left of the Save button.
Once the Custom Files area is open, you can click and drag files into that area or click the blank space in this area to open a file selection menu and select files directly from your computer. Athumbnail representation of image files will display along with the file name.
Note: The Custom Files area of the CSS Editor will only accept valid image (.jpg, .png, .gif) or font files. You cannot upload any other type of files in this area.

Step 4 - Use Uploaded Files (Optional)[top]

If you have uploaded image or font files within the Custom Files area of the CSS editor, you probably want to use them in your code. The quickest way to do this is to write your code to the point where you need the file url to reference. Then, leave the cursor where you want to place the URL in the code and then click the file. The CSS Editor will automatically paste in the direct URL for that file so you can easily reference it in your code.

Step 5 - Save Changes[top]

As you add code in the CSS Editor, the text Unsaved will display in the bottom bar of the editor.
Once you are finished making changes to the code, click the Save button to save those changes to your live style.
When you have finished all changes, you can close the Style Editor by clicking the X that displays in the Preview Editor.