.page-about {
  background: var(--paper);
  color: var(--text);
  font-family: var(--font-body);
  line-height: 1.75;
}

/* ---------- 面包屑条 ---------- */
.page-about .about-crumb {
  background: var(--paper-2);
  border-bottom: 1px solid var(--line);
  padding: 0.9rem 0;
}

/* ---------- 首屏主题声明 ---------- */
.page-about .about-statement {
  position: relative;
  overflow: hidden;
  background: var(--ink);
  color: var(--paper);
  padding: clamp(2.5rem, 7vw, 4.75rem) 0 clamp(2rem, 5vw, 3.25rem);
}

.page-about .about-statement::before {
  content: "";
  position: absolute;
  top: 0;
  left: 0;
  right: 0;
  height: 14px;
  background-image: repeating-linear-gradient(90deg, var(--line-inverse-strong) 0 1px, transparent 1px 44px);
}

.page-about .about-statement::after {
  content: "";
  position: absolute;
  top: -30%;
  right: -15%;
  width: 55%;
  height: 160%;
  background: linear-gradient(112deg, transparent 42%, rgba(62, 156, 143, 0.18) 50%, transparent 58%);
  pointer-events: none;
}

.page-about .about-statement > .shell {
  position: relative;
  z-index: 1;
}

.page-about .about-kicker {
  margin: 0;
  font-family: var(--font-mono);
  font-size: 0.78rem;
  letter-spacing: 0.16em;
  color: var(--teal);
}

.page-about .about-headline {
  margin: 0.9rem 0 0;
  max-width: 15em;
  font-family: var(--font-title);
  font-weight: 800;
  font-size: clamp(2rem, 5.2vw, 3.5rem);
  line-height: 1.2;
  letter-spacing: 0.01em;
}

.page-about .about-lede {
  margin: 1.35rem 0 0;
  max-width: 46ch;
  font-size: clamp(1rem, 1.6vw, 1.1rem);
  color: rgba(233, 230, 222, 0.82);
}

/* ---------- 首屏数据 ---------- */
.page-about .about-figs {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(150px, 1fr));
  gap: 1.5rem 2.25rem;
  margin-top: 2.5rem;
  padding-top: 1.75rem;
  border-top: 1px solid var(--line-inverse);
}

.page-about .about-fig__num {
  display: block;
  font-family: var(--font-mono);
  font-size: clamp(1.9rem, 4vw, 2.75rem);
  font-weight: 700;
  line-height: 1;
  letter-spacing: -0.01em;
  color: var(--amber);
}

.page-about .about-fig__label {
  display: block;
  margin-top: 0.6rem;
  font-size: 0.88rem;
  color: rgba(233, 230, 222, 0.72);
}

/* ---------- 首屏目录 ---------- */
.page-about .about-toc {
  margin-top: clamp(2rem, 4vw, 3rem);
}

.page-about .about-toc__list {
  list-style: none;
  margin: 0;
  padding: 0;
  display: grid;
  grid-template-columns: 1fr;
  gap: 1px;
  background: var(--line-inverse);
  border-top: 1px solid var(--line-inverse);
  border-bottom: 1px solid var(--line-inverse);
}

.page-about .about-toc__item {
  display: block;
}

.page-about .about-toc__link {
  display: grid;
  grid-template-columns: 2.6rem 1fr auto;
  align-items: baseline;
  gap: 0.85rem;
  padding: 0.9rem 1rem;
  background: var(--ink);
  color: var(--paper);
  text-decoration: none;
  transition: background 0.18s ease, box-shadow 0.18s ease;
}

.page-about .about-toc__link:hover,
.page-about .about-toc__link:focus-visible {
  background: var(--hull);
}

.page-about .about-toc__link[aria-current="true"] {
  background: var(--hull);
  box-shadow: inset 3px 0 0 var(--amber);
}

.page-about .about-toc__num {
  font-family: var(--font-mono);
  font-size: 0.8rem;
  color: var(--teal);
}

.page-about .about-toc__label {
  font-family: var(--font-title);
  font-weight: 700;
  font-size: 1.02rem;
}

.page-about .about-toc__meta {
  font-family: var(--font-mono);
  font-size: 0.72rem;
  letter-spacing: 0.08em;
  color: rgba(233, 230, 222, 0.55);
}

@media (min-width: 780px) {
  .page-about .about-toc__list {
    grid-template-columns: 1fr 1fr;
  }
}

/* ---------- 正文区 ---------- */
.page-about .about-body {
  padding: clamp(2.5rem, 6vw, 4.5rem) 0 0;
}

.page-about .about-chapter {
  margin-bottom: clamp(3rem, 7vw, 5rem);
  scroll-margin-top: calc(var(--header-h) + 1.25rem);
}

.page-about .about-prose {
  max-width: 68ch;
}

.page-about .about-prose p {
  margin: 0 0 1rem;
}

.page-about .about-prose--tight {
  margin-top: 1.75rem;
}

/* ---------- 服务对象 ---------- */
.page-about .about-serve {
  display: grid;
  grid-template-columns: 1fr;
  gap: 1px;
  margin-top: 1.75rem;
  background: var(--line);
  border: 1px solid var(--line);
}

.page-about .about-serve__item {
  background: var(--paper-2);
  padding: 1.5rem 1.35rem;
}

.page-about .about-serve__item h3 {
  margin: 0 0 0.5rem;
  font-family: var(--font-title);
  font-size: 1.08rem;
  color: var(--ink);
}

.page-about .about-serve__item p {
  margin: 0;
  font-size: 0.94rem;
  color: rgba(28, 35, 33, 0.78);
}

@media (min-width: 820px) {
  .page-about .about-serve {
    grid-template-columns: repeat(3, 1fr);
  }
}

/* ---------- 图片 ---------- */
.page-about .about-figure {
  margin: 0 0 2.25rem;
}

.page-about .about-figure img {
  display: block;
  width: 100%;
  height: auto;
  max-width: 100%;
  object-fit: cover;
  background: var(--paper-2);
}

.page-about .about-figure--cut img {
  clip-path: polygon(0 0, calc(100% - 26px) 0, 100% 26px, 100% 100%, 0 100%);
}

.page-about .about-figure__cap {
  margin-top: 0.65rem;
  font-size: 0.82rem;
  color: var(--muted);
}

/* ---------- 时间线 ---------- */
.page-about .about-phases {
  list-style: none;
  margin: 0;
  padding: 0;
}

.page-about .about-phase {
  position: relative;
  display: grid;
  gap: 0.75rem;
  padding: 0 0 2.25rem 1.6rem;
  border-left: 1px solid var(--line-strong);
}

.page-about .about-phase::before {
  content: "";
  position: absolute;
  left: -5.5px;
  top: 0.5rem;
  width: 10px;
  height: 10px;
  background: var(--paper);
  border: 2px solid var(--amber);
  transform: rotate(45deg);
}

.page-about .about-phase:last-child {
  border-left-color: transparent;
  padding-bottom: 0;
}

.page-about .about-phase__mark {
  display: flex;
  flex-wrap: wrap;
  align-items: baseline;
  gap: 0.6rem;
}

.page-about .about-phase__no {
  font-family: var(--font-mono);
  font-size: 1.6rem;
  font-weight: 700;
  line-height: 1;
  color: var(--ink);
}

.page-about .about-phase__era {
  font-family: var(--font-mono);
  font-size: 0.78rem;
  letter-spacing: 0.1em;
  color: var(--amber);
}

.page-about .about-phase__name {
  font-size: 0.85rem;
  color: var(--muted);
}

.page-about .about-phase__title {
  margin: 0 0 0.5rem;
  font-family: var(--font-title);
  font-size: clamp(1.15rem, 2vw, 1.4rem);
  line-height: 1.35;
  color: var(--ink);
}

.page-about .about-phase__body p {
  margin: 0 0 0.6rem;
  max-width: 62ch;
}

.page-about .about-phase__data {
  display: flex;
  flex-wrap: wrap;
  gap: 0.5rem 0.65rem;
  margin-top: 0.6rem;
}

@media (min-width: 860px) {
  .page-about .about-phase {
    grid-template-columns: 210px 1fr;
    gap: 0 2.5rem;
    padding-left: 2.5rem;
  }
}

/* ---------- 团队 ---------- */
.page-about .about-team {
  display: grid;
  grid-template-columns: 1fr;
  gap: 2rem;
  margin-top: 1.75rem;
}

.page-about .about-team__nums {
  display: grid;
  gap: 1.5rem;
}

.page-about .about-team__num {
  border-top: 2px solid var(--field);
  padding-top: 0.75rem;
}

.page-about .about-team__num b {
  display: block;
  font-family: var(--font-mono);
  font-size: clamp(2rem, 4vw, 2.6rem);
  font-weight: 700;
  line-height: 1;
  color: var(--field);
}

.page-about .about-team__num span {
  display: block;
  margin-top: 0.5rem;
  font-size: 0.88rem;
  color: rgba(28, 35, 33, 0.72);
}

.page-about .about-team__text p {
  margin: 0;
}

.page-about .about-flow {
  list-style: none;
  margin: 1.35rem 0 0;
  padding: 0;
  display: grid;
  gap: 0.85rem;
}

.page-about .about-flow li {
  position: relative;
  padding-left: 1.7rem;
  font-size: 0.95rem;
  color: rgba(28, 35, 33, 0.86);
}

.page-about .about-flow li::before {
  content: "";
  position: absolute;
  left: 0;
  top: 0.68em;
  width: 14px;
  height: 1px;
  background: var(--teal);
}

.page-about .about-map {
  display: block;
  width: 100%;
  max-width: 560px;
  height: auto;
  margin: 2rem 0 0;
}

.page-about .about-map rect {
  fill: var(--field);
}

.page-about .about-map rect.faint {
  fill: rgba(47, 125, 106, 0.4);
}

.page-about .about-map__cap {
  margin: 0.75rem 0 0;
  max-width: 58ch;
  font-size: 0.86rem;
  color: var(--muted);
}

@media (min-width: 880px) {
  .page-about .about-team {
    grid-template-columns: 260px 1fr;
    gap: 3rem;
  }
}

/* ---------- 合作生态 ---------- */
.page-about .about-partners {
  display: grid;
  grid-template-columns: 1fr;
  gap: 1.25rem;
  margin-top: 1.75rem;
}

.page-about .about-partner {
  background: var(--paper-2);
  border: 1px solid var(--line);
  border-top: 3px solid var(--field);
  padding: 1.5rem 1.4rem;
  clip-path: polygon(0 0, 100% 0, 100% calc(100% - 18px), calc(100% - 18px) 100%, 0 100%);
}

.page-about .about-partner h3 {
  margin: 0.85rem 0 0.5rem;
  font-family: var(--font-title);
  font-size: 1.08rem;
  line-height: 1.4;
  color: var(--ink);
}

.page-about .about-partner p {
  margin: 0;
  font-size: 0.94rem;
  color: rgba(28, 35, 33, 0.78);
}

@media (min-width: 880px) {
  .page-about .about-partners {
    grid-template-columns: repeat(3, 1fr);
    align-items: start;
  }

  .page-about .about-partner:nth-child(2) {
    margin-top: 2.25rem;
  }

  .page-about .about-partner:nth-child(3) {
    margin-top: 4.5rem;
  }
}

/* ---------- 年度专题 ---------- */
.page-about .about-annual {
  display: grid;
  grid-template-columns: 1fr;
  gap: 2rem;
  margin-top: 1.75rem;
}

.page-about .about-vol {
  border-top: 1px solid var(--line);
}

.page-about .about-vol:last-child {
  border-bottom: 1px solid var(--line);
}

.page-about .about-vol summary {
  display: flex;
  align-items: baseline;
  gap: 0.85rem;
  padding: 1rem 0.2rem;
  cursor: pointer;
  list-style: none;
  font-family: var(--font-title);
  font-weight: 700;
  font-size: 1.02rem;
  color: var(--ink);
  transition: background 0.16s ease;
}

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

.page-about .about-vol summary::before {
  content: "+";
  flex: none;
  font-family: var(--font-mono);
  color: var(--amber);
}

.page-about .about-vol[open] summary::before {
  content: "–";
}

.page-about .about-vol summary:hover,
.page-about .about-vol summary:focus-visible {
  background: rgba(14, 27, 42, 0.04);
}

.page-about .about-vol__no {
  flex: none;
  font-family: var(--font-mono);
  font-size: 0.78rem;
  font-weight: 400;
  letter-spacing: 0.08em;
  color: var(--muted);
}

.page-about .about-vol p {
  margin: 0 0 1.1rem;
  padding-left: 1.6rem;
  max-width: 60ch;
  font-size: 0.94rem;
  color: rgba(28, 35, 33, 0.8);
}

.page-about .about-annual__media {
  margin: 0;
}

.page-about .about-annual__media img {
  display: block;
  width: 100%;
  height: auto;
  max-width: 100%;
  object-fit: cover;
  background: var(--paper-2);
  clip-path: polygon(0 0, 100% 0, 100% 100%, 22px 100%, 0 calc(100% - 22px));
}

@media (min-width: 900px) {
  .page-about .about-annual {
    grid-template-columns: 1.25fr 0.85fr;
    gap: 3rem;
    align-items: start;
  }
}

/* ---------- 下一步 ---------- */
.page-about .about-roadmap {
  display: grid;
  grid-template-columns: 1fr;
  gap: 1px;
  margin-top: 1.75rem;
  background: var(--line);
  border: 1px solid var(--line);
}

.page-about .about-road {
  background: var(--paper-2);
  padding: 1.6rem 1.4rem;
}

.page-about .about-road__no {
  margin: 0;
  font-family: var(--font-mono);
  font-size: 0.78rem;
  letter-spacing: 0.1em;
  color: var(--bronze);
}

.page-about .about-road h3 {
  margin: 0.65rem 0 0.5rem;
  font-family: var(--font-title);
  font-size: 1.05rem;
  color: var(--ink);
}

.page-about .about-road p {
  margin: 0;
  font-size: 0.93rem;
  color: rgba(28, 35, 33, 0.78);
}

@media (min-width: 820px) {
  .page-about .about-roadmap {
    grid-template-columns: repeat(3, 1fr);
  }
}

/* ---------- 结尾行动区 ---------- */
.page-about .about-cta {
  background: var(--hull);
  color: var(--paper);
  padding: clamp(1.75rem, 4vw, 2.75rem);
  margin-bottom: clamp(2.5rem, 6vw, 4rem);
  clip-path: polygon(0 0, calc(100% - 26px) 0, 100% 26px, 100% 100%, 0 100%);
}

.page-about .about-cta h2 {
  margin: 0 0 0.75rem;
  font-family: var(--font-title);
  font-size: clamp(1.35rem, 2.6vw, 1.9rem);
  line-height: 1.3;
}

.page-about .about-cta p {
  margin: 0 0 1.5rem;
  max-width: 58ch;
  color: rgba(233, 230, 222, 0.8);
}

.page-about .about-cta__actions {
  display: flex;
  flex-wrap: wrap;
  gap: 0.85rem;
}

@media (max-width: 480px) {
  .page-about .about-toc__link {
    grid-template-columns: 2.2rem 1fr;
  }

  .page-about .about-toc__meta {
    display: none;
  }

  .page-about .about-cta__actions .btn {
    width: 100%;
    text-align: center;
  }
}