<!DOCTYPE html>
<html>
<head>
  <meta charset="utf-8">
  <title>Random Hex Code Generator</title>
  <meta name="viewport" content="width=device-width, initial-scale=1.0">
  <link rel="stylesheet" type="text/css" href="style.css">
    <link href="https://fonts.googleapis.com/css2?family=IBM+Plex+Sans&display=swap" rel="stylesheet">
</head>
<body>
  <div class="flex-row-outer">
    <div class="flex-row">
      <span id="hexCode">#000000</span>
      <button class="colorBtn" onClick="GenerateCode()">Generate</button>
    </div>
  </div>
  <script type="text/javascript">
    let body = document.querySelector("body");
    let hexCode = document.querySelector("#hexCode");
    body.style.backgroundColor = hexCode.innerText;

    function GenerateCode() {
      let RandomColor = "";
      let Char = "0123456789abcdefghijklmnopqrstuvwxyz";

      for(i = 0; i < 6; i++) {
        RandomColor = RandomColor + Char[Math.floor(Math.random() * 16)];
      }
      hexCode.innerText = "#" + RandomColor;
      body.style.backgroundColor = "#" + RandomColor;
    }
  </script>
</body>
</html>

* {
  padding: 0;
  margin: 0;
  font-family: 'IBM Plex Sans', sans-serif;
} 
body {
    height: 100vh;
}
.flex-row-outer {
    display: flex;
    align-items: center;
    justify-content: center;
    height: 100%;
}
.colorBtn {
    background-color: #0f62fe;
    border: 1px solid transparent;
    color: #fff;
    cursor: pointer;
    font-size: 18px;
    width: 100%;
    text-align: left;
    outline: none;
    line-height: 25px;
    padding: calc(.875rem - 3px) 60px calc(.875rem - 3px) 20px;
}
span#hexCode {
    color: #fff;
    display: block;
    padding: calc(.875rem - 3px) 60px calc(.875rem - 3px) 20px;
}

External CSS

This Pen doesn't use any external CSS resources.

External JavaScript

This Pen doesn't use any external JavaScript resources.