代码片段：https://developers.weixin.qq.com/s/UmGf10mP79jB

真机预览可以看到，在某些组件层级结构下，字体加粗后颜色异常（变浅）。如下图：

符号字体文件：https://auction-cdn.nocode.com/nc-symbol.ttf?t=9

参考规范： “Although the practice is not well-loved by typographers, bold faces are often synthesized by user agents for families that lack actual bold faces. For the purposes of font matching, these faces must be treated as if they exist within the family. Authors can explicitly avoid this behavior by using the font-synthesis property.” （ https://www.w3.org/TR/css-fonts-4/#missing-weights）