웹 페이지에 기둥을 하나 만들어서 좌우로 리사이징을 하는 JS // Query the element const resizer = document.getElementById("resizer"); const leftSide = resizer.previousElementSibling; const rightSide = resizer.nextElementSibling; // The Current Position of mouse let x = 0; let y = 0; // Width of left side let leftWidth = 0; // Handle the mousedown event // that's triggered when user drags the resizer const mouseDownHandle..