/* canvas-scale.js · 1280×720 等比缩放
 * 来源：skill-present/lib/player/canvas-scale.js
 * 将 body 内容缩放到 1280×720 设计画布，适配任意视口
 */
(function() {
  var W = 1280, H = 720;
  function scale() {
    var sw = window.innerWidth, sh = window.innerHeight;
    var r = Math.min(sw / W, sh / H);
    document.body.style.transform = 'scale(' + r + ')';
    document.body.style.transformOrigin = 'top left';
    document.body.style.width = W + 'px';
    document.body.style.height = H + 'px';
    document.body.style.overflow = 'hidden';
  }
  window.addEventListener('resize', scale);
  scale();
})();