.page-about {
  --about-gutter: clamp(1.25rem, 4vw, 2.75rem);
  --about-grid-line: rgba(200, 162, 74, 0.13);
  --about-sec-line: rgba(200, 162, 74, 0.16);
  background-color: var(--ink);
  color: var(--cream);
  overflow-x: clip;
}

/* 首屏 */
.page-about .about-hero {
  position: relative;
  padding-block: clamp(1.75rem, 4vw, 3rem) clamp(2.25rem, 5vw, 4rem);
  background-color: var(--ink);
  background-image:
    linear-gradient(180deg, rgba(30, 74, 63, 0.55), rgba(12, 36, 31, 0) 72%),
    linear-gradient(to right, var(--about-grid-line) 1px, transparent 1px),
    linear-gradient(to bottom, var(--about-grid-line) 1px, transparent 1px);
  background-size: 100% 100%, 92px 92px, 92px 92px;
  border-bottom: 1px solid var(--line-gold);
  overflow: hidden;
}

.page-about .about-hero-grid {
  display: grid;
  grid-template-columns: minmax(0, 1fr);
  gap: clamp(1.75rem, 4vw, 3rem);
  margin-top: clamp(1.5rem, 4vw, 2.75rem);
}

.page-about .about-hero h1 {
  margin: 0.7rem 0 0;
  font-family: var(--font-display);
  font-weight: 900;
  font-size: clamp(2rem, 4.6vw, 3.4rem);
  line-height: 1.16;
  letter-spacing: -0.02em;
  color: var(--cream);
  max-width: 17em;
}

.page-about .about-hero-lede {
  margin: 1.25rem 0 0;
  font-family: var(--font-editorial);
  font-size: var(--fs-lead);
  line-height: 1.7;
  color: var(--gold-light);
  max-width: 40ch;
}

.page-about .about-hero-note {
  margin: 0.9rem 0 0;
  font-size: 0.98rem;
  line-height: 1.75;
  color: var(--text-soft);
  max-width: 44ch;
}

.page-about .about-hero-plate {
  position: relative;
  display: grid;
  place-items: center;
  gap: 0.5rem;
  aspect-ratio: 1 / 1;
  max-width: 240px;
  padding: 1.5rem;
  border: 1px solid var(--line-gold);
  border-radius: var(--radius-lg);
  background:
    radial-gradient(circle at 32% 22%, rgba(63, 200, 190, 0.2), transparent 62%),
    linear-gradient(155deg, var(--ink-2), var(--ink));
  clip-path: polygon(14% 0, 100% 0, 100% 86%, 86% 100%, 0 100%, 0 14%);
}

.page-about .about-plate-mark {
  font-family: var(--font-mono);
  font-size: clamp(2.4rem, 6vw, 3.4rem);
  letter-spacing: 0.06em;
  color: var(--gold);
}

.page-about .about-plate-note {
  font-family: var(--font-mono);
  font-size: 0.75rem;
  letter-spacing: 0.08em;
  color: var(--text-mute);
  text-align: center;
}

/* 双栏骨架 */
.page-about .about-layout {
  display: grid;
  grid-template-columns: minmax(0, 1fr);
  gap: clamp(2rem, 4vw, 3.25rem);
  padding-block: clamp(2.25rem, 5vw, 4rem);
}

.page-about .about-main {
  min-width: 0;
}

.page-about .about-aside {
  display: grid;
  gap: 1rem;
  align-content: start;
}

.page-about .about-panel {
  padding: 1.15rem 1.2rem 1.35rem;
  border: 1px solid var(--line-gold);
  border-radius: var(--radius-md);
  background: linear-gradient(160deg, rgba(30, 74, 63, 0.6), rgba(20, 52, 44, 0.92));
}

.page-about .about-panel-title,
.page-about .about-toc-title {
  margin: 0;
  font-family: var(--font-mono);
  font-size: 0.8125rem;
  letter-spacing: 0.08em;
  color: var(--gold);
}

.page-about .about-stats {
  list-style: none;
  margin: 0.85rem 0 0;
  padding: 0;
  display: grid;
  gap: 0.9rem;
}

.page-about .about-stats li {
  padding-top: 0.7rem;
  border-top: 1px solid var(--line-cyan);
}

.page-about .about-stat-num {
  display: block;
  font-family: var(--font-mono);
  font-size: 1.65rem;
  letter-spacing: 0.02em;
  color: var(--gold-light);
}

.page-about .about-stat-label {
  display: block;
  margin-top: 0.25rem;
  font-size: 0.8125rem;
  line-height: 1.6;
  color: var(--text-soft);
}

.page-about .about-toc {
  padding: 1.15rem 1.2rem;
  border: 1px solid var(--line-cyan);
  border-radius: var(--radius-md);
  background-color: rgba(20, 52, 44, 0.55);
}

.page-about .about-toc-list {
  list-style: none;
  margin: 0.8rem 0 0;
  padding: 0;
  display: grid;
  gap: 0.15rem;
}

.page-about .about-toc-link {
  display: flex;
  align-items: baseline;
  gap: 0.7rem;
  padding: 0.45rem 0.4rem;
  border-radius: var(--pill);
  font-size: 0.9375rem;
  color: var(--text-soft);
  text-decoration: none;
  transition: color var(--ease), background-color var(--ease), padding-left var(--ease);
}

.page-about .about-toc-num {
  font-family: var(--font-mono);
  font-size: 0.8125rem;
  letter-spacing: 0.08em;
  color: var(--cyan);
}

.page-about .about-toc-link:hover,
.page-about .about-toc-link:focus-visible {
  color: var(--cream);
  background-color: rgba(63, 200, 190, 0.12);
  padding-left: 0.7rem;
}

/* 章节 */
.page-about .about-sec {
  padding-block: clamp(1.75rem, 4vw, 2.75rem);
  border-top: 1px solid var(--about-sec-line);
}

.page-about .about-sec:first-child {
  padding-top: 0;
  border-top: 0;
}

.page-about .about-sec-head {
  margin-bottom: 1.1rem;
}

.page-about .about-sec h2 {
  margin: 0;
  font-family: var(--font-display);
  font-weight: 900;
  font-size: var(--fs-h2);
  line-height: 1.24;
  letter-spacing: -0.01em;
  color: var(--cream);
}

.page-about .about-sec-lede {
  margin: 0.7rem 0 0;
  font-family: var(--font-editorial);
  font-size: 1.0625rem;
  line-height: 1.7;
  color: var(--gold-light);
  max-width: 38ch;
}

.page-about .about-sec p {
  margin: 0.85rem 0 0;
  font-size: var(--fs-body);
  line-height: 1.8;
  color: var(--text-soft);
  max-width: 40ch;
}

.page-about .about-more {
  margin-top: 1.35rem;
}

/* 图片 */
.page-about .about-figure {
  margin: clamp(1.35rem, 3vw, 2rem) 0 0;
}

.page-about .about-figure img {
  display: block;
  width: 100%;
  max-width: 100%;
  height: auto;
  border: 1px solid var(--line-gold);
  border-radius: var(--radius-md);
  background-color: var(--ink-2);
  object-fit: cover;
}

.page-about .about-figure figcaption {
  margin-top: 0.6rem;
  font-family: var(--font-mono);
  font-size: 0.75rem;
  letter-spacing: 0.04em;
  line-height: 1.6;
  color: var(--text-mute);
}

.page-about .about-figure--right {
  width: min(100%, 500px);
  margin-left: auto;
}

/* 四类资料 */
.page-about .about-cats {
  display: grid;
  gap: 0.85rem;
  margin-top: 1.35rem;
}

.page-about .about-cat {
  position: relative;
  padding-inline: 1.15rem;
  border: 1px solid var(--line-gold);
  border-radius: var(--radius-md);
  background: linear-gradient(135deg, rgba(30, 74, 63, 0.62), rgba(20, 52, 44, 0.34));
  transition: transform var(--ease), border-color var(--ease), background-color var(--ease);
}

.page-about .about-cat:nth-child(1) { padding-block: 1.55rem; }
.page-about .about-cat:nth-child(2) { padding-block: 1.35rem; }
.page-about .about-cat:nth-child(3) { padding-block: 1.15rem; }
.page-about .about-cat:nth-child(4) { padding-block: 0.95rem; }

.page-about .about-cat:hover,
.page-about .about-cat:focus-within {
  transform: translateY(-4px);
  border-color: rgba(63, 200, 190, 0.45);
  background-color: rgba(30, 74, 63, 0.5);
}

.page-about .about-cat-num {
  display: block;
  font-family: var(--font-mono);
  font-size: 0.875rem;
  letter-spacing: 0.08em;
  color: var(--gold);
}

.page-about .about-cat-title {
  margin: 0.3rem 0 0;
  font-family: var(--font-display);
  font-weight: 900;
  font-size: 1.2rem;
  letter-spacing: -0.01em;
  color: var(--cream);
}

.page-about .about-cat p {
  margin: 0.4rem 0 0.7rem;
  max-width: 38ch;
}

.page-about .about-who {
  display: inline-block;
  padding: 0.15rem 0.7rem;
  border: 1px solid var(--line-cyan);
  border-radius: var(--pill);
  font-family: var(--font-mono);
  font-size: 0.75rem;
  letter-spacing: 0.04em;
  color: var(--cyan);
  transition: border-color var(--ease), color var(--ease);
}

.page-about .about-cat:hover .about-who,
.page-about .about-cat:focus-within .about-who {
  border-color: var(--gold);
  color: var(--gold-light);
}

/* 时间轴 */
.page-about .about-timeline {
  position: relative;
  list-style: none;
  margin: 1.35rem 0 0;
  padding: 0 0 0 1.85rem;
}

.page-about .about-timeline::before {
  content: "";
  position: absolute;
  left: 0.35rem;
  top: 0.6rem;
  bottom: 0.6rem;
  width: 1px;
  background: linear-gradient(180deg, var(--gold), var(--cyan-deep));
}

.page-about .about-tl-item {
  position: relative;
  padding-block: 0.35rem 0.85rem;
}

.page-about .about-tl-item::before {
  content: "";
  position: absolute;
  left: -1.62rem;
  top: 1rem;
  width: 9px;
  height: 9px;
  border: 1px solid var(--gold);
  border-radius: 50%;
  background-color: var(--ink);
  box-shadow: 0 0 0 3px rgba(200, 162, 74, 0.12);
}

.page-about .about-tl-item summary {
  display: flex;
  align-items: center;
  gap: 0.7rem;
  padding: 0.2rem 0;
  cursor: pointer;
  list-style: none;
  font-family: var(--font-display);
  font-weight: 900;
  font-size: 1.0625rem;
  line-height: 1.5;
  color: var(--cream);
  transition: color var(--ease);
}

.page-about .about-tl-item summary::-webkit-details-marker {
  display: none;
}

.page-about .about-tl-item summary::after {
  content: "+";
  margin-left: auto;
  font-family: var(--font-mono);
  font-size: 0.9375rem;
  color: var(--cyan);
}

.page-about .about-tl-item details[open] > summary {
  color: var(--gold-light);
}

.page-about .about-tl-item details[open] > summary::after {
  content: "−";
  color: var(--gold);
}

.page-about .about-ver {
  flex: none;
  padding: 0.12rem 0.62rem;
  border: 1px solid var(--line-gold);
  border-radius: var(--pill);
  font-family: var(--font-mono);
  font-size: 0.8125rem;
  font-weight: 400;
  letter-spacing: 0.08em;
  color: var(--gold);
}

.page-about .about-tl-body {
  margin-top: 0.5rem !important;
  max-width: 42ch;
}

/* 浅色区 */
.page-about .about-sec.about-sand {
  margin-block: clamp(1.25rem, 3vw, 2rem);
  padding: clamp(1.5rem, 4vw, 2.5rem);
  border-top: 0;
  border-radius: var(--radius-lg);
  background-color: var(--sand);
  color: var(--charcoal);
}

.page-about .about-sand h2 {
  color: var(--charcoal);
}

.page-about .about-sand .about-sec-lede {
  color: #4A5249;
}

.page-about .about-sand p {
  color: rgba(35, 40, 37, 0.84);
}

.page-about .about-steps {
  list-style: none;
  margin: 1.2rem 0 0;
  padding: 0;
  display: grid;
  gap: 1.1rem;
}

.page-about .about-step {
  position: relative;
  padding-left: 2.7rem;
}

.page-about .about-step::before {
  content: "";
  position: absolute;
  left: 0;
  top: 0.25rem;
  width: 1.9rem;
  height: 1.5rem;
  border: 1px solid rgba(27, 127, 121, 0.45);
  border-radius: var(--pill);
  background-color: rgba(27, 127, 121, 0.12);
}

.page-about .about-step:nth-child(1)::after { content: "01"; }
.page-about .about-step:nth-child(2)::after { content: "02"; }
.page-about .about-step:nth-child(3)::after { content: "03"; }
.page-about .about-step:nth-child(4)::after { content: "04"; }

.page-about .about-step::after {
  position: absolute;
  left: 0;
  top: 0.25rem;
  width: 1.9rem;
  height: 1.5rem;
  display: grid;
  place-items: center;
  font-family: var(--font-mono);
  font-size: 0.75rem;
  letter-spacing: 0.04em;
  color: var(--cyan-deep);
}

.page-about .about-step-title {
  margin: 0;
  font-family: var(--font-display);
  font-weight: 900;
  font-size: 1.0625rem;
  color: var(--charcoal);
}

.page-about .about-step p {
  margin-top: 0.35rem;
  max-width: 42ch;
}

/* 服务地区 */
.page-about .about-coverage {
  display: grid;
  grid-template-columns: minmax(0, 1fr);
  gap: 1.25rem;
  align-items: start;
}

.page-about .about-coverage-figure {
  margin-top: 1rem;
}

.page-about .about-coverage-text p {
  margin-top: 0.8rem;
}

/* 合作与社群 */
.page-about .about-partner-grid {
  display: grid;
  grid-template-columns: minmax(0, 1fr);
  gap: 0.85rem;
  margin-top: 1.2rem;
}

.page-about .about-partner {
  padding: 1rem 1.1rem 1.15rem;
  border: 1px solid var(--line-cyan);
  border-radius: var(--radius-md);
  background-color: rgba(20, 52, 44, 0.5);
}

.page-about .about-partner-title {
  margin: 0;
  font-family: var(--font-display);
  font-weight: 900;
  font-size: 1.0625rem;
  color: var(--cream);
}

.page-about .about-partner p {
  margin-top: 0.4rem;
  font-size: 0.98rem;
  max-width: 36ch;
}

.page-about .about-stats-band {
  display: grid;
  grid-template-columns: repeat(2, minmax(0, 1fr));
  gap: 0.75rem;
  margin-top: 1.25rem;
  padding-top: 1.25rem;
  border-top: 1px solid var(--about-sec-line);
}

.page-about .about-stat {
  padding: 0.85rem 0.9rem;
  border: 1px solid var(--line-gold);
  border-radius: var(--radius-md);
  background: linear-gradient(150deg, rgba(30, 74, 63, 0.55), rgba(12, 36, 31, 0.4));
}

.page-about .about-stat-value {
  display: block;
  font-family: var(--font-mono);
  font-size: 1.35rem;
  letter-spacing: 0.02em;
  color: var(--gold-light);
}

.page-about .about-stat-name {
  display: block;
  margin-top: 0.3rem;
  font-size: 0.8125rem;
  line-height: 1.6;
  color: var(--text-soft);
}

/* 一起做内容 */
.page-about .about-sec.about-join {
  margin-top: clamp(1.25rem, 3vw, 2rem);
  padding: clamp(1.5rem, 4vw, 2.5rem);
  border: 1px solid var(--line-gold);
  border-radius: var(--radius-lg);
  background:
    radial-gradient(circle at 88% 8%, rgba(63, 200, 190, 0.16), transparent 58%),
    linear-gradient(150deg, var(--ink-2), var(--ink));
}

.page-about .about-join-actions {
  display: flex;
  flex-wrap: wrap;
  gap: 0.7rem;
  margin-top: 1.4rem;
}

.page-about .about-join-note {
  margin-top: 1.1rem !important;
  font-family: var(--font-mono);
  font-size: 0.8125rem;
  line-height: 1.7;
  letter-spacing: 0.02em;
  color: var(--text-mute) !important;
}

/* 断点 */
@media (min-width: 720px) {
  .page-about .about-coverage {
    grid-template-columns: 260px minmax(0, 1fr);
    gap: 1.75rem;
  }

  .page-about .about-coverage-figure {
    margin-top: 0.9rem;
  }

  .page-about .about-partner-grid {
    grid-template-columns: repeat(3, minmax(0, 1fr));
  }
}

@media (min-width: 900px) {
  .page-about .about-hero-grid {
    grid-template-columns: minmax(0, 1fr) 240px;
    align-items: end;
  }

  .page-about .about-hero-plate {
    max-width: none;
  }
}

@media (min-width: 960px) {
  .page-about .about-layout {
    grid-template-columns: minmax(0, 1fr) 320px;
    grid-template-areas: "main aside";
    align-items: start;
  }

  .page-about .about-main {
    grid-area: main;
  }

  .page-about .about-aside {
    grid-area: aside;
    position: sticky;
    top: 104px;
  }

  .page-about .about-stats-band {
    grid-template-columns: repeat(4, minmax(0, 1fr));
  }
}

@media (max-width: 599px) {
  .page-about .about-hero h1 {
    max-width: none;
  }

  .page-about .about-figure--right {
    width: 100%;
  }

  .page-about .about-join-actions .btn {
    flex: 1 1 auto;
    justify-content: center;
    text-align: center;
  }
}