我知道我可以写:
$('.2020').css("padding", "20px");
但是我该怎么写:
$('.a').children('img').children('.2020').css("padding", "20px");
<div class"a">
<img class="2020" src="img/swatch/2020.jpg" >
<img class="2021" src="img/swatch/2021.jpg" >
<img class="2022" src="img/swatch/2022.jpg" >
</div>