.section-title {
  margin: 48px 0 64px; /* 上を少し詰める */
}

.section-title__heading {
  font-size: 1.5rem;   /* 24px */
  font-weight: 450;
  letter-spacing: 0.06em;
  color: #454545;
  text-align: center;
}



/* SP */
@media (max-width: 768px) {
  .section-title__heading {
    font-size: 1.5rem;    /* SPも同じでOK */
  }
}