Above the board, the next disc floats over the column under the mouse, in the color of the player whose turn it is. It
shows where a click will drop.
```js
canvas.addEventListener('pointermove', (event) => {
hoverCol = colAt(event)
})
// The next disc waits above the column it would drop into.
disc(hoverCol * CELL + CELL / 2, TOP - CELL / 2, COLORS[turn])
```
What it means
pointermove happens whenever the mouse moves over the canvas: it updates hoverCol.
The disc is drawn in the middle of that column, half a cell above the board (TOP - CELL / 2 = 64).
Your turn
Above the pointerdown listener write the pointermove listener.
In draw, above ctx.fillStyle = '#1d4ed8', write the comment and the disc line, followed by an empty line.
Skills: Keyboard and mouse input, Drawing on a canvas