<details>
  <summary>Click Me!</summary>
  <p>Hello! I am a looooooonnnnngggggg content</p>
</details>
details {
  margin: 30px;
}

summary {
  width: 14rem;
  height: 2rem;
  background-color: rgba(0, 0, 0, 0.2);
  padding: 12px;
  color: #000000;
  border-radius: 6px;
  text-align: center;
  line-height: 2;
  cursor: pointer;
}
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