.box {
  background-color: #e4e4e4;
}

.box__heading {
  padding: 15px 20px;

  background-color: rgba(0, 0, 0, 0.15);
}
.box__heading h1,
.box__heading h2,
.box__heading h3,
.box__heading h4,
.box__heading h5,
.box__heading h6 {
  margin: 0;

  /* These are technically the same, but use both */
  overflow-wrap: break-word;
  word-wrap: break-word;

  -ms-word-break: break-all;
  /* This is the dangerous one in WebKit, as it breaks things wherever */
  word-break: break-all;
  /* Instead use this non-standard one: */
  word-break: break-word;

  /* Adds a hyphen where the word breaks, if supported (No Blink) */
  -ms-hyphens: auto;
  -moz-hyphens: auto;
  -webkit-hyphens: auto;
  hyphens: auto;
}
.box__body {
  padding: 15px 20px;

  /* These are technically the same, but use both */
  overflow-wrap: break-word;
  word-wrap: break-word;

  -ms-word-break: break-all;
  /* This is the dangerous one in WebKit, as it breaks things wherever */
  word-break: break-all;
  /* Instead use this non-standard one: */
  word-break: break-word;

  /* Adds a hyphen where the word breaks, if supported (No Blink) */
  -ms-hyphens: auto;
  -moz-hyphens: auto;
  -webkit-hyphens: auto;
  hyphens: auto;
}