.activity-section {
  padding-top: 112px;
  padding-bottom: 112px;
  border-top: 1px solid var(--line);
}

.activity-section-alt {
  background: var(--paper2);
  box-shadow: 50vw 0 0 var(--paper2), -50vw 0 0 var(--paper2);
}

.activity-section > h2 {
  margin: 24px 0 18px;
  color: var(--ink);
  font-size: clamp(40px, 4.35vw, 62px);
}

.activity-lead {
  max-width: 780px;
  margin-bottom: 20px;
  color: var(--green);
  font-family: var(--serif);
  font-size: clamp(23px, 2.2vw, 31px);
  line-height: 1.45;
}

.activity-introduction {
  max-width: 820px;
  margin-bottom: 48px;
}

.activity-introduction p,
.activity-conclusion p,
.activity-experience p {
  color: #62596a;
  font-size: 15px;
}

.activity-entry {
  padding: 28px 0 24px;
  border-top: 1px solid var(--line);
}

.activity-entry h3,
.activity-conclusion h3,
.activity-experience h3 {
  margin-bottom: 10px;
  color: var(--green);
  font-family: var(--serif);
  font-size: 26px;
  font-weight: 400;
  letter-spacing: -.02em;
}

.activity-summary {
  max-width: 820px;
  margin-bottom: 6px;
  color: #62596a;
  font-size: 15px;
}

.activity-more {
  border: 0;
  padding: 0;
}

.activity-more summary {
  display: inline-block;
  padding: 2px 0;
  border-bottom: 1px solid rgba(23, 105, 79, .45);
  color: var(--green);
  font-size: 14px;
  font-weight: 600;
  list-style: none;
}

.activity-more summary::-webkit-details-marker {
  display: none;
}

.activity-more .more-closed {
  display: none;
}

.activity-more[open] .more-open {
  display: none;
}

.activity-more[open] .more-closed {
  display: inline;
}

.activity-more-content {
  max-width: 900px;
  padding-top: 17px;
}

.activity-more-content p,
.activity-more-content li {
  color: #554d63;
  font-size: 15px;
  line-height: 1.85;
}

.activity-more-content h4 {
  margin: 20px 0 8px;
  color: var(--green);
  font-size: 15px;
}

.activity-more-content ul {
  margin: 0;
  padding-left: 23px;
}

.activity-conclusion {
  max-width: 900px;
  margin-top: 30px;
  padding-top: 30px;
  border-top: 1px solid var(--line);
}

.activity-experience {
  max-width: 900px;
  margin-top: 34px;
  padding: 28px 30px 20px;
  border: 1px solid var(--line);
  background: var(--paper);
}

@media (max-width: 760px) {
  .activity-section {
    padding-top: 82px;
    padding-bottom: 84px;
  }

  .activity-section > h2 {
    font-size: clamp(39px, 9.5vw, 54px);
  }

  .activity-lead {
    font-size: 25px;
  }

  .activity-introduction {
    margin-bottom: 34px;
  }

  .activity-entry h3,
  .activity-conclusion h3,
  .activity-experience h3 {
    font-size: 23px;
  }

  .activity-experience {
    padding: 24px 22px 16px;
  }
}