CSS Class custom

Hi,

After that i see css custom properties , think that if creating Class
custom for CSS can help us. Nowadays we have that install preprocessor CSS
to and using this preprocessor CSS  can using variables. Now lets change
how make CSS variables, see example below:
So can we working very fast with changes in projects of way correct,
without worry with files CSS, that continue pretty good.

:root{
/*create class*/
--btn-default{
    width:50px;
    height:30px;
    font-size:15px;
    font-weight:bold;
    }
}
..btn-confirm{
    class(--btn-default);/*call class*/
    color:green;
}

-- 
*Leonardo Lima*
*Web developer*

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