How can I modify the style of the Latex formula section. eg font, padding

[LJjia]

I tried to use katex in css but it doesn't work.like this

.katex-display {
  font-size:1.22em; 
}
.katex
{
  padding-left:8px;
  padding-right: 8px;
}

[Cz1544252489]

I have met the same problem and cant solve it even I tried approaches that works on web. I think the css environment cant fit well while the math format in latex shows great.