Return all custom properties (CSS variables) declared on :root in the document's stylesheets.
Stylesheets whose rules can't be read, such as cross-origin ones, are skipped.
Returns {key:string;value:string}[]
Array of CSS variable objects with key and value properties
Return all custom properties (CSS variables) declared on
:rootin the document's stylesheets. Stylesheets whose rules can't be read, such as cross-origin ones, are skipped.