<div class="my-block">
  <h3>Очень длинный заголовок</h3>
<div class="block">
  <p>Lorem ipsum dolor sit, amet consectetur adipisicing elit. Non, labore temporibus. Dolore quod autem, neque dolorem ipsum sapiente suscipit numquam soluta repudiandae impedit repellat adipisci voluptates porro? Sequi, ab excepturi.</p>
</div>

.my-block {
  display: block;
  max-width: 50%;
  margin: 0 auto;
}
.my-block h3 {
  display: inline-block;
  max-width: 90%;
  padding: 10px;
  position: relative;
  top: 40px;
  left: 20px;
  background: #fff;
  color: #ff0000;
}
.block {
  padding: 20px;
  border: 2px solid #ff0000;
}