varh=widthAndHeight('height','#main')-(50+42+40)-(2*heightOfTextarea)-(2*42)-(2*10);// height of main - (height of thumb - height of h2 + height of footer) - 2* heightOfTextarea - 2* height of h2 - 2* padding
varh=window.innerHeight-(50+40);// height of main - (height of header - height of footer)