font weight bold,font：bold; 与 font-weight：bold;有什么区别？

font weight bold,font：bold; 与 font-weight：bold;有什么区别？详细介绍

p.normal {font-weight: normal}p.thick {font-weight: bold}p.thicker {font-weight: 900}

This is a paragraph.

This is a paragraph.

This is a paragraph.

This is a paragraph.