.koumin-core {
  font-size: 1.05em;
  line-height: 1.8;
}

.blank {
  background: #eeeeee;
  color: transparent;
  border: 1px solid #cccccc;
  border-radius: 3px;
  padding: 0 0.25em;
  cursor: pointer;
  transition: background .2s ease, color .2s ease, font-size .2s ease, border-color .2s ease;
}

.blank.open {
  background: #f7f9fc;
  border-color: #9db5e5;
  color: #1e4fa1;
  font-weight: 600;
  font-size: 1.12em;
}

.blank:hover {
  background: #e3eaf7;
}