JSFiddle - React, Tailwind, and code Playground

HTML

<svg class="me" width="145" height="65">
    <rect class="rect_style rect_color_1 rect_obvious" x="3" y="3" rx="20" ry="20" width="140" height="60">
</svg>
<button id="bntTest" type="button">remove</button>

CSS

.rect_style {
      stroke:black;
      stroke-width:5;
  }
  .rect_color_1 {
      fill:#FFC863;
  }
  .rect_obvious {
      opacity: .5;
  }
  .rect_none {
      opacity: 0;
  }

JavaScript

$(document).ready(function () {
    $('#bntTest').on('click', function () {
        var classData = $(".me rect").attr('class');
        $(".me rect").attr('class', classData.replace('rect_obvious', ''));
        alert($(".me rect").attr('class'));
    });
});