Undefined CSS Variable

Wat veroorzaakt deze fout

The var() function references a custom property (--my-var) that is not defined in the current scope or any ancestor. Custom properties follow CSS inheritance and scoping rules.

Hoe op te lossen

Define the custom property on :root or the appropriate ancestor element. Use a fallback value: var(--my-var, fallback). Check for typos in the custom property name.

div { color: var(--undefined-var); }