function selectBackgroundEffect() {
	$(document).ready( function() {
		var seekret = Math.random();
		if (seekret > 0.3) {
			//if (seekret > 0.6) {
				// Dark background, changes quickly
				currentValue = 0.07;
				hueChangeSpeed = 0.03; 				
				doRotateBackgroundHue(document.body);
				setInterval(function () {
					doRotateBackgroundHue(document.body);
				}, 50);
		//	} 
            
            //else {
				// Bright colors, change slowly
			//	currentValue = 1.0;
			//	hueChangeSpeed = 0.001;
			//	doRotateBackgroundHue(document.body);
			//	setInterval(function () {
			//		doRotateBackgroundHue(document.body);
			//	}, 100);				
			//}

		} else {
			// do nothing, we leave a white background
		}		
	});
}

var currentHue = Math.random();
var currentValue = 1.0;
var currentValueDir = -1.0;

var currentSaturation = 1.0;
var currentSaturationDir = -1.0;

var hueChangeSpeed = 0.0;

function doRotateBackgroundCrazy(domElement) {
	var color = hsv2rgb(currentHue,currentSaturation,currentValue); // 0.1
	domElement.style.backgroundColor = 'rgb(' + color['red'] + ',' + color['green'] + ',' + color['blue'] + ')';
	currentHue += 0.00015;
	if (currentHue > 1.0) currentHue = 0.0;

	if (currentValue > 1.0 || currentValue < 0.99) currentValueDir *= -1.0;
	currentValue += 0.0192/300 * currentValueDir;

	if (currentSaturation > 1.0 || currentSaturation < 0.0) currentSaturationDir *= -1.0;
	currentSaturation += 0.022123/300 * currentSaturationDir;
}

function doRotateBackgroundHue(domElement) {
	var color = hsv2rgb(currentHue,currentSaturation,currentValue); // 0.1
	domElement.style.backgroundColor = 'rgb(' + color['red'] + ',' + color['green'] + ',' + color['blue'] + ')';
	currentHue += hueChangeSpeed;
	if (currentHue > 1.0) currentHue = 0.0;
}

function hsv2rgb(h,s,v) {
// Adapted from http://www.easyrgb.com/math.html
// hsv values = 0 - 1, rgb values = 0 - 255
var r, g, b;
var RGB = new Array();
if(s==0){
  RGB['red']=RGB['green']=RGB['blue']=Math.round(v*255);
}else{
  // h must be < 1
  var var_h = h * 6;
  if (var_h==6) var_h = 0;
  //Or ... var_i = floor( var_h )
  var var_i = Math.floor( var_h );
  var var_1 = v*(1-s);
  var var_2 = v*(1-s*(var_h-var_i));
  var var_3 = v*(1-s*(1-(var_h-var_i)));
  if(var_i==0){ 
    var_r = v; 
    var_g = var_3; 
    var_b = var_1;
  }else if(var_i==1){ 
    var_r = var_2;
    var_g = v;
    var_b = var_1;
  }else if(var_i==2){
    var_r = var_1;
    var_g = v;
    var_b = var_3
  }else if(var_i==3){
    var_r = var_1;
    var_g = var_2;
    var_b = v;
  }else if (var_i==4){
    var_r = var_3;
    var_g = var_1;
    var_b = v;
  }else{ 
    var_r = v;
    var_g = var_1;
    var_b = var_2
  }
  //rgb results = 0 ÷ 255  
  RGB['red']=Math.round(var_r * 255);
  RGB['green']=Math.round(var_g * 255);
  RGB['blue']=Math.round(var_b * 255);
  }
return RGB;  
};