<details>
  <summary>Summary</summary>
  <p>The border-radius in here doesn't inherit.</p>
</details>

<div>
  <p>The border-radius here inherits just fine.</p>
</div>
details {
  border-radius: 10px;
}
details p {
  background: black;
  color: white;
  padding: 10px;
  margin: 0;
}
details summary {
  font-weight: 800;
  background: #d1c4e9;
  padding: 0.5rem;
  border-radius: inherit;
}
details[open] summary {
  margin: 0 0 10px 0;
}
details p {
  border-radius: inherit;
}

body {
  font-family: "Georama", sans-serif;
  line-height: 1.4;
  background: #7e57c2;
  max-width: 400px;
  margin: 2rem auto;
  padding: 2rem;
}

div {
  border-radius: 8px;
}
div > p {
  border-radius: inherit;
  background: #fff9c4;
  padding: 0.5rem;
}
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