Fix problem with html5 contentEditable field

I have a issue with a modest contentEditable field in html5 that I want to fix

1) If I establish a contentEditable field in html5 with a small fontSize and zero scaling then all goes well each line can be as long as the screen can take

2) But in my app I want to set the fontSize large around 120 pixels as well as then elements are scaled down consequently if I do that if I set fontSize large as well as then I use css3 transforms to scale down the div then the problem happens that afterward a certain width of typing and a new line is created therefore I cannot do text lines longer than x pixels because new lines are created.

Desired Skills are HTML5