使用CSS来突出显示给定的表头和单元格悬停的第一个表行

I would like to use CSS only in order to highlight both the table header and the first line of the table row i.e. if the user hovers on a given table cell, the corresponding table header (say Tuesday) and the corresponding first td (say nighttime) will change to bold say.I would like to use CSS only in order to highli