[BM] Night Mode

javascript: (function() {
 function RGBtoHSL(RGBColor) {
  with(Math) {
   var R, G, B;
   var cMax, cMin;
   var sum, diff;
   var Rdelta, Gdelta, Bdelta;
   var H, L, S;
   R = RGBColor[0];
   G = RGBColor[1];
   B = RGBColor[2];
   cMax = max(max(R, G), B);
   cMin = min(min(R, G), B);
   sum = cMax + cMin;
   diff = cMax - cMin;
   L = sum / 2;
   if (cMax == cMin) {
    S = 0;
    H = 0;
   } else {
    if (L <= (1 / 2)) S = diff / sum;
    else S = diff / (2 - sum);
    Rdelta = R / 6 / diff;
    Gdelta = G / 6 / diff;
    Bdelta = B / 6 / diff;
    if (R == cMax) H = Gdelta - Bdelta;
    else if (G == cMax) H = (1 / 3) + Bdelta - Rdelta;
    else H = (2 / 3) + Rdelta - Gdelta;
    if (H < 0) H += 1;
    if (H > 1) H -= 1;
   }
   return [H, S, L];
  }
 }

 function getRGBColor(node, prop) {
  var rgb = getComputedStyle(node, null).getPropertyValue(prop);
  var r, g, b;
  if (/rgb\((\d+),\s(\d+),\s(\d+)\)/.exec(rgb)) {
   r = parseInt(RegExp.$1, 10);
   g = parseInt(RegExp.$2, 10);
   b = parseInt(RegExp.$3, 10);
   return [r / 255, g / 255, b / 255];
  }
  return rgb;
 }

 function hslToCSS(hsl) {
  return "hsl(" + Math.round(hsl[0] * 360) + ", " + Math.round(hsl[1] * 100) + "%, " + Math.round(hsl[2] * 100) + "%)";
 }
 var props = ["color", "background-color", "border-left-color", "border-right-color", "border-top-color", "border-bottom-color"];
 var props2 = ["color", "backgroundColor", "borderLeftColor", "borderRightColor", "borderTopColor", "borderBottomColor"];
 if (typeof getRGBColor(document.documentElement, "background-color") == "string") document.documentElement.style.backgroundColor = "white";
 revl(document.documentElement);

 function revl(n) {
  var i, x, color, hsl;
  if (n.nodeType == Node.ELEMENT_NODE) {
   for (i = 0; x = n.childNodes[i]; ++i) revl(x);
   for (i = 0; x = props[i]; ++i) {
    color = getRGBColor(n, x);
    if (typeof(color) != "string") {
     hsl = RGBtoHSL(color);
     hsl[2] = 1 - hsl[2];
     n.style[props2[i]] = hslToCSS(hsl);
    }
   }
  }
 }
})()