I am using Visual Studio Code for a pure HTML, JavaScript and CSS project. I imported a CSS file from an old project that was provided to me by a colleague and a few of the lines in the CSS file are marked as having an error in VS Code, such as this one:

.some-class .some-sub-class {
   padding-left: calc(~"50px + .75rem");
}

VS Code notes two errors here:

• ) expected (squiggly line under the tilde)
• at-rule or selector expected (squiggly line under the closing bracket)

I was able to determine that both errors were caused by the tilde ~ character, since removing it suppresses the errors, but I need the tilde for those CSS rules.

The file is just a .css file if that’s relevant, and simply closing it doesn’t show any error anymore.

Is there an extension I should add, remove, or configure to make that error go away?

here are the extensions I have installed so far. The issue was happening before I installed any of them:

>Solution :

This is not valid CSS format, this seems to be LessCSS, which means you’d have to select proper filetype: Less.