Need CSS for restyling bold

Could one of the CSS wizards tell me/direct me to instructions for how to change the weight of bold typeface so that it matches whatever (lighter) weight the UI redesign is using for Concept cards? Or, I guess, the other way, but I like the lighter weight.

I don’t even know where to look for information about this.

Thanks

.concept_rem_type{
	font-weight: 400;
}

With this code you can change the weight of Concept type…
400 is normal text
600 is weight of Concept
700 is weight of bold

OK, thanks very much. So this changes Concept to match Bold. Is it possible to change Bold to match Concept?

/* set the text bold to be as bold as the default concept bold */
.bold {
    font-weight: 600; /* default is 700 */
}