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.container
input.hex(placeholder='Enter hex color')
.palette
@import url('https://fonts.googleapis.com/css2?family=Roboto+Mono&display=swap')
.hex
padding 10px
font-size 2rem
outline none
margin-bottom 20px
text-transform uppercase
letter-spacing 0.05em
font-family 'Roboto Mono', monospace
border 4px solid #D3D3D3
border-radius 4px
outline none
color #292929
&::placeholder
color #CECECE
&.error
border-color red !important
color red
&:focus
border-color #777777
.palette
display grid
grid-template-columns repeat(auto-fit, minmax(120px, 1fr))
.color
padding 15px
font-size 0.7em
letter-spacing 0.07em
text-transform uppercase
transition all 200ms ease
border 3px solid transparent
&:hover
&.current
transform scale(1.2)
border-radius 5px
z-index 1
border 3px solid
box-shadow 0 10px 15px -3px rgba(0, 0, 0, 0.2), 0 4px 6px -2px rgba(0, 0, 0, 0.15)
&:hover
z-index 2
.container
max-width 800px
margin 0 auto
display flex
flex-direction column
.generate
padding 20px
font-size 1.5rem
background black
color white
outline none
border none
cursor pointer
margin-bottom 30px
text-transform uppercase
letter-spacing 0.1em
&:hover
background rgba(black, 0.8)
body
padding 30px
overflow-x hidden
font-family 'Roboto Mono', monospace
padding-bottom 100px
// color conversion code from: https://css-tricks.com/converting-color-spaces-in-javascript/
function hexToHSL(H) {
// Convert hex to RGB first
let r = 0,
g = 0,
b = 0;
if (H.length == 4) {
r = "0x" + H[1] + H[1];
g = "0x" + H[2] + H[2];
b = "0x" + H[3] + H[3];
} else if (H.length == 7) {
r = "0x" + H[1] + H[2];
g = "0x" + H[3] + H[4];
b = "0x" + H[5] + H[6];
}
// Then to HSL
r /= 255;
g /= 255;
b /= 255;
let cmin = Math.min(r, g, b),
cmax = Math.max(r, g, b),
delta = cmax - cmin,
h = 0,
s = 0,
l = 0;
if (delta == 0) h = 0;
else if (cmax == r) h = ((g - b) / delta) % 6;
else if (cmax == g) h = (b - r) / delta + 2;
else h = (r - g) / delta + 4;
h = Math.round(h * 60);
if (h < 0) h += 360;
l = (cmax + cmin) / 2;
s = delta == 0 ? 0 : delta / (1 - Math.abs(2 * l - 1));
s = +(s * 100).toFixed(1);
l = +(l * 100).toFixed(1);
return [h, s, l];
}
function HSLToHex(h, s, l) {
s /= 100;
l /= 100;
let c = (1 - Math.abs(2 * l - 1)) * s,
x = c * (1 - Math.abs(((h / 60) % 2) - 1)),
m = l - c / 2,
r = 0,
g = 0,
b = 0;
if (0 <= h && h < 60) {
r = c;
g = x;
b = 0;
} else if (60 <= h && h < 120) {
r = x;
g = c;
b = 0;
} else if (120 <= h && h < 180) {
r = 0;
g = c;
b = x;
} else if (180 <= h && h < 240) {
r = 0;
g = x;
b = c;
} else if (240 <= h && h < 300) {
r = x;
g = 0;
b = c;
} else if (300 <= h && h < 360) {
r = c;
g = 0;
b = x;
}
// Having obtained RGB, convert channels to hex
r = Math.round((r + m) * 255).toString(16);
g = Math.round((g + m) * 255).toString(16);
b = Math.round((b + m) * 255).toString(16);
// Prepend 0s, if necessary
if (r.length == 1) r = "0" + r;
if (g.length == 1) g = "0" + g;
if (b.length == 1) b = "0" + b;
return "#" + r + g + b;
}
// ----------------------------
const isValidHex = (x) => /^#([0-9A-F]{3}){1,2}$/i.test(x);
const palettes = document.querySelector(".palette");
const hexInput = document.querySelector(".hex");
hexInput.addEventListener("input", (e) => {
const hex = e.target.value;
if (isValidHex(hex)) {
e.target.classList.remove("error");
palettes.innerHTML = "";
const [h, s, l] = hexToHSL(hexInput.value);
paletteGen(h, s, l);
} else {
e.target.classList.add("error");
error = true;
}
});
const textColor = (h, s, l) => {
const shift = l < 50 ? 50 : -50;
return HSLToHex(h, s, l + shift);
};
const paletteGen = (h, s, lightness) => {
const start = lightness % 10;
for (let l = start; l < 100; l += 2) {
const hex = HSLToHex(h, s, l);
const color = document.createElement("div");
color.className = "color";
color.style.backgroundColor = hex;
color.style.color = textColor(h, s, l);
if (lightness === l) {
color.classList.add("current");
}
color.textContent = hex;
palettes.appendChild(color);
}
};
// default palette
const defaultColor = "#777777";
paletteGen(...hexToHSL(defaultColor));
hexInput.value = defaultColor;
Also see: Tab Triggers