<header>
  <h2 class="title">Document</h2>
  <p class="description">Динамічне управління DOM.</p>
</header>
<main>
  <div class="result">
    <button id="addElementBtn">Додати елемент</button>
    <button id="changeColorBtn">Змінити колір</button>
    <div id="contentArea"></div>
  </div>
</main>

body {
  font-size: 16px;
  line-height: 1.5;
  font-family: monospace;
}

header {
  background-color: #f1f1f1;
  margin-bottom: 25px;
  padding: 15px;
  -webkit-box-shadow: 0px 0px 3px 0px rgba(118, 118, 118, 1);
  -moz-box-shadow: 0px 0px 3px 0px rgba(118, 118, 118, 1);
  box-shadow: 0px 0px 3px 0px rgba(118, 118, 118, 1);
}

header h2.title {
  padding-bottom: 15px;
  border-bottom: 1px solid #999;
}

header p.description {
  font-style: italic;
  color: #222;
}

.result {
  background-color: #f8f8f8;
  padding: 15px;
  -webkit-box-shadow: 0px 0px 3px 0px rgba(118, 118, 118, 1);
  -moz-box-shadow: 0px 0px 3px 0px rgba(118, 118, 118, 1);
  box-shadow: 0px 0px 3px 0px rgba(118, 118, 118, 1);
}

button {
  margin: 5px;
  padding: 10px 15px;
  background-color: #4CAF50;
  color: white;
  border: none;
  border-radius: 4px;
  cursor: pointer;
}

button:hover {
  background-color: #45a049;
}

#contentArea {
  margin-top: 15px;
  padding: 10px;
  border: 1px solid #ddd;
}

document.getElementById("addElementBtn").addEventListener("click", function() {
  let newElement = document.createElement("p");
  newElement.textContent = "Новий елемент";
  document.getElementById("contentArea").appendChild(newElement);
});

document.getElementById("changeColorBtn").addEventListener("click", function() {
  let contentArea = document.getElementById("contentArea");
  contentArea.style.color = contentArea.style.color === 'red' ? 'black' : 'red';
});

External CSS

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External JavaScript

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