... vertically or horizontally. If a div is 50 0 pixels from the left border of the win-dow, and you add 5 to the left property, you will move the div to a position 50 5 pixels from the border. Unfortunately, ... example:document.getElementById('myDiv').style.left = parseInt(document.getElementById('myDiv').style.left) + 5; To move a div 5 pixels to the left, subtract 5 from the value of the leftproperty as follows:document.getElementById('myDiv').style.left ... could write this:checkrangenumeric(100, error, 50 , 150 )To make sure a number is over some value, you could write this:checkrangenumeric(100, error, 50 , null)Similarly, if you want to see whether...