.css — Cascading Style Sheets
A stylesheet language that describes the visual presentation (colors, layout, fonts) of HTML documents.
Safety guidance (not a guarantee)
Source code is plain text and doesn't execute on its own — it has to be compiled or run by a specific tool, which is where any real risk would occur.
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Frequently asked questions
What is a .css file?
A stylesheet language that describes the visual presentation (colors, layout, fonts) of HTML documents.
Can I edit a .css file?
Yes — .css files are commonly editable with software such as Any web browser.
Does having a .css extension mean the file is safe?
No single extension can guarantee that. Source code is plain text and doesn't execute on its own — it has to be compiled or run by a specific tool, which is where any real risk would occur. Always consider where the file came from, not just its name.
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