function twentytwentyoneResponsiveEmbeds(){
var proportion, parentWidth;
document.querySelectorAll('iframe').forEach(function(iframe){
if(iframe.width&&iframe.height){
proportion=parseFloat(iframe.width) / parseFloat(iframe.height);
parentWidth=parseFloat(window.getComputedStyle(iframe.parentElement, null).width.replace('px', ''));
iframe.style.maxWidth='100%';
iframe.style.maxHeight=Math.round(parentWidth / proportion).toString() + 'px';
}});
}
twentytwentyoneResponsiveEmbeds();
window.onresize=twentytwentyoneResponsiveEmbeds;