:root{--sans-regular-font-family:Helvetica,Arial,STHeiti,华文黑体,"Microsoft YaHei",微软雅黑,SimSun,宋体;--sans-regular-font-style:normal;--sans-regular-font-weight:400;--sans-bold-font-family:Helvetica,Arial,STHeiti,华文黑体,"Microsoft YaHei",微软雅黑,SimSun,宋体;--sans-bold-font-style:normal;--sans-bold-font-weight:700}