Shows a crosshair at specific coordinates

showCrosshair.js

function toPx(a) {
    return a.toString() + "px";
}

function showLine(x, y, width, height, color) {
    const $a = document.createElement("div");
    document.body.append($a);
    
    $a.style.width = toPx(width);
    $a.style.height = toPx(height);
    $a.style.backgroundColor = color;

    $a.style.zIndex = 99999;
    $a.style.position = "absolute";
    $a.style.top = toPx(y - height/2);
    $a.style.left = toPx(x - width/2);
}

function showCrossHair(x, y, size = 7, thickness = 1, color = "red") {
    showLine(x, y, size, thickness, color);
    showLine(x, y, thickness, size, color);
}