[firep91613]

Подскажите, почему не вставляется?

const rect = `<svg width="500" height="250">
				<rect x="5" y="5" width="490" height="240" style="fill: white; stroke: gray; stroke-width: 5;" />
			  </svg>`;

document.body.insertAdjacentHTML('afterbegin', rect);

function createCicrle(cx, cy, r = 20) {
  let circle = document.createElementNS('http://www.w3.org/2000/svg', 'circle');
  circle.setAttribute('r', r);
  circle.setAttribute('cx', cx);
  circle.setAttribute('cy', cy);
  circle.setAttribute('fill', 'red');
  circle.setAttribute('stroke-width', 1);
  return circle;
}

let h = document.getElementsByTagName('rect')[0].getBBox().height;
let r = 20;
let cy = h / 2 - (r / 2);
let cx = r;

document.getElementsByTagName('rect')[0].append(createCicrle(cx, cy, r));