.wrap690 {
  width: 690px;
  margin-left: auto;
  margin-right: auto;
}

.flex_dl {
  display: flex;
}
.period {
  display: flex;
  gap: 5px;
  flex-wrap: wrap;
}
.color_dark {
  color: #333;
}


@media screen and (max-width: 640px){



}