<script>
     (function (win) {
       win.egProps = {
         modal: {
           campaigns: [
             {
               campaignId: "395648",
               elementSelector: "#donateBTN",
               urlParams: readURLParams()
             }
           ]
         }
       };

       win.document.body.appendChild(makeEGScript());

       // Create the embed script
       function makeEGScript() {
         var egScript = win.document.createElement("script");
         egScript.setAttribute("type", "text/javascript");
         egScript.setAttribute("async", "true");
         egScript.setAttribute(
           "src",
           "https://sdk.classy.org/embedded-giving.js"
         );

         return egScript;
       }

       // Read URL parameters and pass them to the donation page in the embedded modal
       function readURLParams() {
         var searchParams = new URLSearchParams(location.search);

         // Add or remove url parameters that you want to pass over to the embed modal.
         var validUrlParams = ["c_src", "c_src2"];

         return validUrlParams.reduce(function (urlParamsSoFar, validKey) {
           var value = searchParams.get(validKey);
           return value === null
             ? urlParamsSoFar
             : { ...urlParamsSoFar, [validKey]: value };
         }, {});
       }
     })(window);
   </script>