.page-about {
  --about-measure: 720px;
  background: var(--ink);
  color: var(--paper);
  font-family: var(--font-body);
  overflow-x: hidden;
}

.page-about a {
  color: inherit;
}

/* 首屏 */
.page-about .about-hero {
  position: relative;
  overflow: hidden;
  padding: calc(var(--header-h) + 56px) 0 68px;
  background:
    radial-gradient(circle at 84% 10%, rgba(39, 240, 214, 0.16), transparent 46%),
    radial-gradient(circle at 10% 94%, rgba(255, 107, 44, 0.12), transparent 42%),
    var(--ink);
}

.page-about .about-hero::after {
  content: "";
  position: absolute;
  top: -12%;
  right: -8%;
  width: 60%;
  height: 132%;
  background: linear-gradient(158deg, rgba(23, 41, 68, 0.94), rgba(14, 26, 46, 0.5));
  clip-path: polygon(24% 0, 100% 0, 100% 100%, 0 100%);
  pointer-events: none;
}

.page-about .about-hero-grid {
  position: relative;
  z-index: 1;
  display: grid;
  grid-template-columns: minmax(0, 1fr);
  gap: 28px;
}

.page-about .about-hero-body {
  min-width: 0;
}

.page-about .breadcrumb-list {
  display: flex;
  flex-wrap: wrap;
  gap: 0;
  margin: 0 0 26px;
  padding: 0;
  list-style: none;
  font-size: 13px;
  color: var(--mute);
}

.page-about .breadcrumb-item + .breadcrumb-item::before {
  content: "/";
  margin: 0 10px;
  color: var(--line);
}

.page-about .breadcrumb-link {
  text-decoration: none;
  border-bottom: 1px solid transparent;
  transition: color 0.18s linear, border-color 0.18s linear;
}

.page-about .breadcrumb-link:hover {
  color: var(--cyan);
  border-bottom-color: var(--cyan);
}

.page-about .about-kicker {
  color: var(--orange);
  margin: 0 0 18px;
  letter-spacing: 0.24em;
}

.page-about .about-title {
  margin: 0 0 28px;
  font-family: var(--font-display);
  font-weight: 900;
  font-size: clamp(2.3rem, 6.4vw, 5.4rem);
  line-height: 1.04;
  letter-spacing: -0.04em;
  max-width: 15em;
}

.page-about .about-lead {
  margin: 0;
  max-width: var(--about-measure);
  font-size: clamp(1rem, 1.3vw, 1.15rem);
  line-height: 1.85;
  color: var(--paper);
  opacity: 0.86;
}

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

/* 宽幅档案图 */
.page-about .about-plate {
  margin: 0;
  border-top: 2px solid var(--line);
  border-bottom: 2px solid var(--line);
  background: var(--panel);
}

.page-about .about-plate img {
  display: block;
  width: 100%;
  height: auto;
  object-fit: cover;
}

.page-about .about-plate-cap {
  padding: 10px var(--gutter);
  font-size: 11px;
  letter-spacing: 0.14em;
  color: var(--mute);
  border-top: 1px solid var(--line);
}

/* 题记 */
.page-about .about-pull {
  padding: 56px 0;
  background: var(--panel);
  border-bottom: 1px solid var(--line);
}

.page-about .about-pull blockquote {
  margin: 0;
  padding-left: 22px;
  border-left: 6px solid var(--orange);
}

.page-about .about-pull p {
  margin: 0;
  max-width: 22em;
  font-family: var(--font-display);
  font-weight: 900;
  font-size: clamp(1.45rem, 3.6vw, 2.9rem);
  line-height: 1.3;
  letter-spacing: -0.02em;
}

/* 主体布局 */
.page-about .about-body {
  display: grid;
  grid-template-columns: minmax(0, 1fr);
  gap: 0;
  padding-top: 8px;
  padding-bottom: 64px;
}

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

.page-about .rail-title {
  margin: 0;
  color: var(--mute);
}

.page-about .rail-list {
  margin: 16px 0 0;
  padding: 0;
  list-style: none;
}

.page-about .rail-list a {
  display: block;
  padding: 10px 0 10px 14px;
  border-left: 2px solid var(--line);
  font-size: 14px;
  line-height: 1.5;
  text-decoration: none;
  color: var(--mute);
  transition: color 0.18s linear, border-color 0.18s linear;
}

.page-about .rail-list a:hover,
.page-about .rail-list a:focus-visible {
  color: var(--cyan);
  border-left-color: var(--cyan);
}

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

/* 章节 */
.page-about .about-sec {
  padding: 56px 0;
  border-top: 1px solid var(--line);
  scroll-margin-top: calc(var(--header-h) + 24px);
}

.page-about .about-stream > .about-sec:first-child {
  border-top: 0;
  padding-top: 32px;
}

.page-about .sec-label {
  margin: 0 0 14px;
  font-size: 12px;
  letter-spacing: 0.2em;
  color: var(--cyan);
}

.page-about .sec-label span {
  display: inline-block;
  margin-right: 8px;
  color: var(--mute);
}

.page-about .sec-title {
  margin: 0 0 22px;
  font-family: var(--font-display);
  font-weight: 900;
  font-size: clamp(1.65rem, 3.4vw, 2.85rem);
  line-height: 1.14;
  letter-spacing: -0.03em;
  max-width: 18em;
}

.page-about .sec-body {
  max-width: var(--about-measure);
  font-size: 17px;
  line-height: 1.82;
  color: var(--paper);
  opacity: 0.84;
}

.page-about .sec-body p {
  margin: 0 0 18px;
}

.page-about .sec-body p:last-child {
  margin-bottom: 0;
}

.page-about .archive-jump {
  font-size: 15px;
  color: var(--mute);
}

.page-about .archive-jump a {
  color: var(--gold);
  text-decoration: none;
  border-bottom: 1px solid var(--gold);
}

.page-about .archive-jump a:hover {
  color: var(--cyan);
  border-bottom-color: var(--cyan);
}

/* 六类矩阵 */
.page-about .matrix {
  margin: 34px 0 0;
  padding: 0;
  list-style: none;
  display: grid;
  gap: 12px;
  grid-template-columns: repeat(2, minmax(0, 1fr));
}

.page-about .matrix li {
  border: 1px solid var(--line);
  border-top: 4px solid var(--m-color, var(--cyan));
  background: var(--panel);
  padding: 14px 12px 16px;
  min-width: 0;
}

.page-about .m-idx {
  display: block;
  font-size: 11px;
  letter-spacing: 0.16em;
  color: var(--m-color, var(--cyan));
}

.page-about .matrix h3 {
  margin: 6px 0 8px;
  font-size: 1.02rem;
  font-weight: 800;
  letter-spacing: 0.02em;
}

.page-about .matrix p {
  margin: 0;
  font-size: 13px;
  line-height: 1.66;
  color: var(--mute);
}

/* 章节配图 */
.page-about .sec-figure {
  margin: 32px 0 0;
  border: 1px solid var(--line);
  background: var(--panel);
}

.page-about .sec-figure img {
  display: block;
  width: 100%;
  height: auto;
  object-fit: cover;
}

.page-about .sec-figure figcaption {
  padding: 10px 14px;
  font-size: 12px;
  line-height: 1.6;
  letter-spacing: 0.04em;
  color: var(--mute);
  border-top: 1px solid var(--line);
}

/* 数据条 */
.page-about .facts {
  margin-top: 30px;
  border: 1px solid var(--line);
  background: var(--raise);
}

.page-about .fact {
  padding: 18px 20px;
  border-top: 1px solid var(--line);
}

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

.page-about .fact-num {
  margin: 0 0 4px;
  font-size: clamp(1.5rem, 3vw, 2rem);
  line-height: 1.1;
  color: var(--cyan);
}

.page-about .fact-label {
  margin: 0 0 6px;
  font-size: 13px;
  font-weight: 700;
  letter-spacing: 0.08em;
  color: var(--paper);
}

.page-about .fact-text {
  margin: 0;
  font-size: 13px;
  line-height: 1.68;
  color: var(--mute);
}

/* 回访四组 */
.page-about .return-list {
  margin: 28px 0 26px;
  padding: 0;
  list-style: none;
  max-width: 860px;
}

.page-about .return-list li {
  display: grid;
  grid-template-columns: 38px minmax(0, 1fr);
  gap: 14px;
  align-items: baseline;
  padding: 18px 0;
  border-bottom: 1px solid var(--line);
}

.page-about .return-list li:first-child {
  border-top: 1px solid var(--line);
}

.page-about .r-idx {
  font-size: 12px;
  letter-spacing: 0.1em;
  color: var(--orange);
}

.page-about .return-list h3 {
  margin: 0 0 6px;
  font-size: 1.08rem;
  font-weight: 800;
}

.page-about .return-list p {
  margin: 0;
  font-size: 15px;
  line-height: 1.72;
  color: var(--mute);
}

/* 版本时间线 */
.page-about .tl {
  margin: 34px 0 0;
  padding: 0 0 0 26px;
  list-style: none;
  border-left: 3px solid var(--line);
  max-width: 860px;
}

.page-about .tl > li {
  position: relative;
  padding: 0 0 26px 18px;
  scroll-margin-top: calc(var(--header-h) + 28px);
}

.page-about .tl > li::before {
  content: "";
  position: absolute;
  left: -31px;
  top: 9px;
  width: 12px;
  height: 12px;
  border-radius: 50%;
  background: var(--gold);
  box-shadow: 0 0 0 4px var(--ink), 0 0 0 5px var(--line);
}

.page-about .tl-ver {
  display: inline-block;
  margin: 0 10px 6px 0;
  font-size: 15px;
  letter-spacing: 0.1em;
  color: var(--gold);
}

.page-about .tl-details summary {
  display: flex;
  align-items: baseline;
  justify-content: space-between;
  gap: 14px;
  padding: 4px 0;
  font-size: 1rem;
  font-weight: 700;
  line-height: 1.55;
  cursor: pointer;
  list-style: none;
}

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

.page-about .tl-details summary::after {
  content: "＋";
  flex: none;
  font-family: var(--font-mono);
  font-size: 14px;
  color: var(--gold);
}

.page-about .tl-details[open] summary::after {
  content: "－";
}

.page-about .tl-details summary:hover {
  color: var(--cyan);
}

.page-about .tl-details p {
  margin: 6px 0 0;
  max-width: 620px;
  font-size: 15px;
  line-height: 1.76;
  color: var(--mute);
}

/* 职能面板 */
.page-about .crew-panel {
  margin-top: 32px;
  padding: clamp(20px, 3.4vw, 44px);
  background: var(--paper);
  color: var(--ink);
  border: 2px solid var(--line);
  box-shadow: var(--shadow-hard);
}

.page-about .crew-title {
  margin: 0;
  font-family: var(--font-display);
  font-weight: 900;
  font-size: clamp(1.1rem, 2vw, 1.4rem);
  letter-spacing: -0.01em;
}

.page-about .crew-grid {
  display: grid;
  grid-template-columns: minmax(0, 1fr);
  gap: 20px;
  margin-top: 24px;
}

.page-about .crew-item {
  min-width: 0;
  border-top: 4px solid var(--ink);
  padding-top: 12px;
}

.page-about .crew-idx {
  margin: 0 0 6px;
  font-size: 12px;
  letter-spacing: 0.18em;
  color: #4a6b96;
}

.page-about .crew-item h3 {
  margin: 0 0 8px;
  font-size: 1.04rem;
  font-weight: 800;
}

.page-about .crew-item p {
  margin: 0;
  font-size: 14px;
  line-height: 1.72;
  color: rgba(7, 14, 28, 0.74);
}

.page-about .crew-note {
  margin: 26px 0 0;
  padding-top: 16px;
  border-top: 1px dashed rgba(7, 14, 28, 0.32);
  font-size: 15px;
  line-height: 1.78;
  color: rgba(7, 14, 28, 0.86);
}

/* 联系方式 */
.page-about .about-contact {
  margin: 28px 0 0;
  border-top: 1px solid var(--line);
  max-width: var(--about-measure);
}

.page-about .about-contact > div {
  display: grid;
  grid-template-columns: minmax(0, 1fr);
  gap: 4px;
  padding: 14px 0;
  border-bottom: 1px solid var(--line);
}

.page-about .about-contact dt {
  font-size: 12px;
  letter-spacing: 0.12em;
  color: var(--mute);
}

.page-about .about-contact dd {
  margin: 0;
  font-size: 15px;
  line-height: 1.7;
  color: var(--paper);
  overflow-wrap: anywhere;
}

.page-about .about-actions {
  display: flex;
  flex-wrap: wrap;
  gap: 12px;
  margin-top: 30px;
}

/* 响应式 */
@media (min-width: 640px) {
  .page-about .matrix {
    grid-template-columns: repeat(3, minmax(0, 1fr));
  }

  .page-about .crew-grid {
    grid-template-columns: repeat(2, minmax(0, 1fr));
  }

  .page-about .about-contact > div {
    grid-template-columns: 116px minmax(0, 1fr);
    align-items: baseline;
    gap: 16px;
  }
}

@media (min-width: 760px) {
  .page-about .facts {
    display: grid;
    grid-template-columns: repeat(3, minmax(0, 1fr));
  }

  .page-about .fact {
    border-top: 0;
    border-left: 1px solid var(--line);
  }

  .page-about .fact:first-child {
    border-left: 0;
  }
}

@media (min-width: 900px) {
  .page-about .about-hero {
    padding: calc(var(--header-h) + 76px) 0 88px;
  }

  .page-about .about-hero-grid {
    grid-template-columns: minmax(0, 1fr) 54px;
    gap: 56px;
  }

  .page-about .about-spine {
    display: block;
    align-self: end;
    justify-self: end;
    margin: 0;
    padding-right: 12px;
    writing-mode: vertical-rl;
    text-orientation: mixed;
    font-size: 11px;
    letter-spacing: 0.34em;
    color: var(--cyan);
    border-right: 1px solid var(--line);
  }
}

@media (min-width: 1000px) {
  .page-about .about-body {
    grid-template-columns: 196px minmax(0, 1fr);
    gap: 64px;
    align-items: start;
    padding-top: 40px;
  }

  .page-about .about-rail {
    display: block;
    position: sticky;
    top: calc(var(--header-h) + 32px);
    padding: 40px 0;
  }

  .page-about .about-sec {
    padding: 68px 0;
  }

  .page-about .about-stream > .about-sec:first-child {
    padding-top: 40px;
  }
}

@media (min-width: 1180px) {
  .page-about .matrix {
    grid-template-columns: repeat(6, minmax(0, 1fr));
  }
}

@media (prefers-reduced-motion: reduce) {
  .page-about .breadcrumb-link,
  .page-about .rail-list a {
    transition: none;
  }
}

.page-about {
  --m-color: currentColor;
}