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@catb0t
Created January 28, 2019 04:57
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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);
}
}
}
}
})()
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