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CSS

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HTML 

              
                <!--* banner -->
<header>
  <div class="page-header">
    <h1>Color Flipper</h1>

    <div class="page-links">
      <span id="hex-page">HEX</span>
      <span id="rgb-page">RGB</span>
      <span id="hsl-page">HSL</span>
    </div>
  </div>
</header>

<!--* body -->
<main>
  <div class="main-wrapper" id="hex-wrapper">
    <p>Change the background color by clicking this button.</p>
    <button id="hex-color">#babfff</button>
  </div>

  <div class="main-wrapper" id="rgb-wrapper">
    <p>Change the background color by clicking this button.</p>
    <button id="rgb-color">rgb(120, 191, 255)</button>
  </div>

  <div class="main-wrapper" id="hsl-wrapper">
    <p>Change the background color by clicking this button.</p>
    <button id="hsl-color">hsl(26, 100%, 86%)</button>
  </div>
</main>
</body>
!

CSS 

              
                /** body */
body {
  background-color: #babfff;
  padding: 20px;
}

/** header */
header {
  width: 100%;
  margin: 20px 0;
  text-align: center;
}

/** page links */
.page-links > span {
  font-weight: bold;
  cursor: pointer;
}

/* first page link */
#hex-page {
  text-decoration: underline;
}

/* second and third page links */
#rgb-wrapper,
#hsl-wrapper {
  display: none;
}

/** main */
.main-wrapper {
  width: 300px;
  margin: 40px auto;
  text-align: center;
}

button {
  margin: 20px;
  padding: 10px 20px;
  font-weight: 600;
  font-size: 110%;
  border: solid 1px grey;
  color: rgb(68, 65, 65);
  border-radius: 3px;
  -webkit-border-radius: 3px;
  -moz-border-radius: 3px;
  -ms-border-radius: 3px;
  -o-border-radius: 3px;
  cursor: pointer;
}
!

JS 

              
                //* variables
// selecting the body element
const changeBackground = document.body;

// selecting the links to change the page
const hexPage = document.getElementById("hex-page");
const rgbPage = document.getElementById("rgb-page");
const hslPage = document.getElementById("hsl-page");

// selecting the main wrappers
const hexWrapper = document.getElementById("hex-wrapper");
const rgbWrapper = document.getElementById("rgb-wrapper");
const hslWrapper = document.getElementById("hsl-wrapper");

// selecting the buttons to change the background
const hexColor = document.getElementById("hex-color");
const rgbColor = document.getElementById("rgb-color");
const hslColor = document.getElementById("hsl-color");

//* adding event listener and function to the color page links
// hex page
hexPage.addEventListener("click", function () {
  if (hexPage.style.textDecoration != "underline") {
    hexWrapper.style.display = "block";
    rgbWrapper.style.display = "none";
    hslWrapper.style.display = "none";
    hexPage.style.textDecoration = "underline";
    rgbPage.style.textDecoration = "none";
    hslPage.style.textDecoration = "none";

    // changes the background color
    changeBackground.style.backgroundColor = hexColor.textContent;
  }
});

// rgb page
rgbPage.addEventListener("click", function () {
  if (rgbPage.style.textDecoration != "underline") {
    rgbWrapper.style.display = "block";
    hexWrapper.style.display = "none";
    hslWrapper.style.display = "none";
    rgbPage.style.textDecoration = "underline";
    hexPage.style.textDecoration = "none";
    hslPage.style.textDecoration = "none";

    // changes the background color
    changeBackground.style.backgroundColor = rgbColor.textContent;
  }
});

// hsl page
hslPage.addEventListener("click", function () {
  if (hslPage.style.textDecoration != "underline") {
    hslWrapper.style.display = "block";
    rgbWrapper.style.display = "none";
    hexWrapper.style.display = "none";
    hslPage.style.textDecoration = "underline";
    rgbPage.style.textDecoration = "none";
    hexPage.style.textDecoration = "none";

    // changes the background color
    changeBackground.style.backgroundColor = hslColor.textContent;
  }
});

//* adding event listener and function to the color buttons
// hex button
// array of values for the background color
const hex = [0, 1, 2, 3, 4, 5, 6, 7, 8, 9, "a", "b", "c", "d", "e", "f"];
let randomNumberValue;

hexColor.addEventListener("click", function () {
  // saves the new background color
  let hexColorValue = "#";
  // randomly picks a value in the array and adds it to the background color above
  for (let i = 0; i < 6; i++) {
    randomNumberValue = Math.floor(Math.random() * hex.length);
    hexColorValue += hex[randomNumberValue];
  }
  // changes the text inside the button
  hexColor.textContent = hexColorValue;
  // changes the background color
  changeBackground.style.background = hexColorValue;
});

// rgb button
rgbColor.addEventListener("click", function () {
  // randomly picks a number between 0 and 255
  let a = Math.floor(Math.random() * 256);
  // randomly picks a number between 0 and 255
  let b = Math.floor(Math.random() * 256);
  // randomly picks a number between 0 and 255
  let c = Math.floor(Math.random() * 256);
  // saves the new background color
  // const rgbColorValue = "rgb(" + a + ", " + b + ", " + c + ")";
  const rgbColorValue = `rgb(${a}, ${b}, ${c})`;
  // changes the text inside the button
  rgbColor.textContent = rgbColorValue;
  // changes the background color
  changeBackground.style.background = rgbColorValue;
});

// hsl button
hslColor.addEventListener("click", function () {
  // randomly picks a number between 0 and 360
  let a = Math.floor(Math.random() * 361);
  // randomly picks a number between 0 and 100
  let b = Math.floor(Math.random() * 101);
  // randomly picks a number between 0 and 100
  let c = Math.floor(Math.random() * 101);
  // saves the new background color
  // const hslColorValue = "hsl(" + a + ", " + b + "%, " + c + "%)";
  const hslColorValue = `hsl(${a}, ${b}%, ${c}%)`;
  // changes the text inside the button
  hslColor.textContent = hslColorValue;
  // changes the background color
  changeBackground.style.background = hslColorValue;
});
!
999px

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