Access CSS variable from javascript [duplicate]

Answer 1

Just the standard way:

1. Get the computed styles with getComputedStyle
2. Use getPropertyValue to get the value of the desired property

getComputedStyle(element).getPropertyValue('--color-font-general');

Example:

var style = getComputedStyle(document.body);
console.log(style.getPropertyValue('--color-font-general'));

:root { --color-font-general: #336699; }

Answer 2

Use this:

window.getComputedStyle(document.documentElement).getPropertyValue('--color-font-general');

And you can change it like this:

document.documentElement.style.setProperty('--color-font-general', '#000');

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