.page-about {
  background: var(--deep);
  color: var(--mist);
  font-family: var(--font-display);
  overflow-x: hidden;
  padding-bottom: 8px;
}

.page-about .eyebrow {
  margin: 0;
  font-family: var(--font-mono);
  font-size: 12px;
  letter-spacing: 0.18em;
  color: var(--cyan);
  text-transform: uppercase;
}

/* 面包屑 */
.page-about .breadcrumb {
  padding: 22px 0 6px;
}

.page-about .breadcrumb__list {
  display: flex;
  flex-wrap: wrap;
  gap: 8px;
  margin: 0;
  padding: 0;
  list-style: none;
  font-family: var(--font-mono);
  font-size: 12px;
  letter-spacing: 0.05em;
  color: var(--gray-cyan);
}

.page-about .breadcrumb__item {
  display: flex;
  align-items: center;
  gap: 8px;
}

.page-about .breadcrumb__item + .breadcrumb__item::before {
  content: "/";
  color: rgba(140, 169, 161, 0.5);
}

.page-about .breadcrumb__link {
  color: var(--gray-cyan);
  text-decoration: none;
  border-bottom: 1px solid transparent;
  transition: color 0.18s var(--ease), border-color 0.18s var(--ease);
}

.page-about .breadcrumb__link:hover,
.page-about .breadcrumb__link:focus-visible {
  color: var(--cyan);
  border-bottom-color: var(--cyan);
}

/* 首屏 */
.page-about .about-hero {
  position: relative;
  padding: 22px 0 44px;
  border-bottom: 1px solid var(--line);
  background:
    radial-gradient(130% 100% at 88% -12%, rgba(53, 224, 208, 0.17), transparent 58%),
    linear-gradient(158deg, rgba(30, 74, 63, 0.6) 0%, rgba(11, 42, 37, 0) 56%);
}

.page-about .about-hero__inner {
  display: grid;
  gap: 32px;
  align-items: center;
}

.page-about .about-hero__text h1 {
  margin: 14px 0 0;
  font-size: clamp(2rem, 6.4vw, 3.4rem);
  line-height: 1.12;
  font-weight: 900;
  letter-spacing: -0.02em;
  color: var(--mist);
}

.page-about .about-hero__lede {
  margin: 16px 0 0;
  max-width: 46ch;
  font-size: 15px;
  line-height: 1.85;
  color: rgba(242, 247, 244, 0.82);
}

.page-about .hero-facts {
  display: grid;
  gap: 12px;
  margin: 26px 0 0;
  padding: 0;
  list-style: none;
}

.page-about .hero-facts li {
  padding-left: 12px;
  border-left: 2px solid var(--cyan);
}

.page-about .hero-facts__num {
  display: block;
  font-family: var(--font-mono);
  font-size: 21px;
  letter-spacing: 0.01em;
  color: var(--gold);
  line-height: 1.2;
}

.page-about .hero-facts__label {
  display: block;
  margin-top: 2px;
  font-size: 12.5px;
  color: var(--gray-cyan);
  line-height: 1.5;
}

.page-about .about-hero__figure {
  position: relative;
}

.page-about .about-hero__figure::before {
  content: "";
  position: absolute;
  inset: -6% -4% -6% 8%;
  background: var(--moss);
  clip-path: polygon(20% 0, 100% 9%, 94% 100%, 0 87%);
  opacity: 0.6;
  z-index: 0;
}

.page-about .about-hero__figure .media-frame {
  position: relative;
  z-index: 1;
}

/* 图像容器 */
.page-about .media-frame {
  border: 1px solid var(--line);
  background: var(--tech);
  box-shadow: 0 20px 44px -30px rgba(0, 0, 0, 0.95);
  overflow: hidden;
}

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

.page-about .media-frame__caption {
  margin: 0;
  padding: 10px 12px;
  border-top: 1px solid var(--line);
  background: rgba(8, 31, 27, 0.72);
  font-family: var(--font-mono);
  font-size: 11.5px;
  letter-spacing: 0.04em;
  color: var(--gray-cyan);
  line-height: 1.6;
}

/* 双栏档案体 */
.page-about .about-body {
  display: grid;
  gap: 34px;
  padding: 36px 0 56px;
}

.page-about .about-toc__title {
  margin: 0 0 12px;
  font-family: var(--font-mono);
  font-size: 11px;
  letter-spacing: 0.22em;
  color: var(--gray-cyan);
  text-transform: uppercase;
}

.page-about .about-toc__list {
  display: flex;
  gap: 8px;
  margin: 0;
  padding: 0 0 8px;
  list-style: none;
  overflow-x: auto;
  -webkit-overflow-scrolling: touch;
}

.page-about .about-toc__list li {
  flex: 0 0 auto;
}

.page-about .about-toc__list a {
  display: inline-flex;
  align-items: baseline;
  gap: 7px;
  padding: 8px 12px;
  border: 1px solid var(--line);
  color: var(--mist);
  text-decoration: none;
  font-size: 13px;
  white-space: nowrap;
  transition: border-color 0.18s var(--ease), color 0.18s var(--ease), background 0.18s var(--ease);
}

.page-about .about-toc__list a span {
  font-family: var(--font-mono);
  font-size: 11px;
  letter-spacing: 0.06em;
  color: var(--gold);
}

.page-about .about-toc__list a:hover,
.page-about .about-toc__list a:focus-visible {
  border-color: var(--cyan);
  color: var(--cyan);
  background: rgba(53, 224, 208, 0.07);
}

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

/* 章节 */
.page-about .about-section {
  padding-top: 30px;
  border-top: 1px solid var(--line);
}

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

.page-about .about-section + .about-section {
  margin-top: 40px;
}

.page-about .about-section__head {
  display: flex;
  align-items: baseline;
  gap: 12px;
  margin-bottom: 16px;
}

.page-about .about-section__code {
  margin: 0;
  font-family: var(--font-mono);
  font-size: 12px;
  letter-spacing: 0.12em;
  color: var(--gold);
}

.page-about .about-section__title {
  margin: 0;
  font-size: clamp(1.32rem, 3.6vw, 1.9rem);
  line-height: 1.28;
  font-weight: 800;
  letter-spacing: -0.01em;
  color: var(--mist);
}

.page-about .about-section > p {
  margin: 0 0 14px;
  max-width: 64ch;
  font-size: 15px;
  line-height: 1.85;
  color: rgba(242, 247, 244, 0.8);
}

.page-about .about-section a {
  color: var(--cyan);
  text-decoration: none;
  border-bottom: 1px solid rgba(53, 224, 208, 0.4);
  transition: border-color 0.18s var(--ease), color 0.18s var(--ease);
}

.page-about .about-section a:hover,
.page-about .about-section a:focus-visible {
  border-bottom-color: var(--cyan);
}

.page-about .about-section__tail {
  margin: 18px 0 0;
  padding-left: 12px;
  border-left: 2px solid var(--gold);
  font-size: 14px;
  line-height: 1.8;
  color: rgba(242, 247, 244, 0.74);
  max-width: 62ch;
}

/* 版本演进 */
.page-about .versions {
  position: relative;
  overflow: hidden;
  padding: 16px;
  border: 1px solid var(--line);
  background: linear-gradient(150deg, rgba(30, 74, 63, 0.85), rgba(23, 59, 54, 0.4) 62%, rgba(11, 42, 37, 0.2));
}

.page-about .versions::before {
  content: "";
  position: absolute;
  top: 0;
  left: 0;
  width: 58%;
  height: 2px;
  background: linear-gradient(90deg, var(--cyan), rgba(53, 224, 208, 0));
}

.page-about .versions__figure {
  margin-bottom: 16px;
}

.page-about .versions__list {
  display: grid;
  gap: 12px;
  margin: 0;
  padding: 0;
  list-style: none;
}

.page-about .vstep {
  position: relative;
  padding: 14px 16px;
  border: 1px solid var(--line);
  background: rgba(8, 31, 27, 0.62);
  transition: border-color 0.2s var(--ease), background 0.2s var(--ease), transform 0.2s var(--ease);
}

.page-about .vstep::after {
  content: "";
  position: absolute;
  top: -1px;
  left: -1px;
  width: 2px;
  height: calc(100% + 2px);
  background: var(--line-strong);
  transition: background 0.2s var(--ease);
}

.page-about .vstep:hover,
.page-about .vstep:focus-within,
.page-about .vstep:focus-visible {
  border-color: var(--cyan);
  background: rgba(23, 59, 54, 0.85);
  transform: translateY(-2px);
  outline: none;
}

.page-about .vstep:hover::after,
.page-about .vstep:focus-within::after {
  background: var(--cyan);
}

.page-about .vstep__code {
  display: block;
  font-family: var(--font-mono);
  font-size: 12px;
  letter-spacing: 0.14em;
  color: var(--gold);
}

.page-about .vstep__name {
  margin: 6px 0 8px;
  font-size: 16px;
  font-weight: 700;
  color: var(--mist);
}

.page-about .vstep__text {
  margin: 0;
  font-size: 13.5px;
  line-height: 1.72;
  color: rgba(242, 247, 244, 0.78);
}

.page-about .vstep__note {
  margin: 10px 0 0;
  font-family: var(--font-mono);
  font-size: 11.5px;
  letter-spacing: 0.03em;
  color: var(--gray-cyan);
  transition: color 0.2s var(--ease);
}

.page-about .vstep:hover .vstep__note,
.page-about .vstep:focus-within .vstep__note {
  color: var(--cyan);
}

/* 团队 */
.page-about .team-grid {
  display: grid;
  gap: 12px;
}

.page-about .team-card {
  border: 1px solid var(--line);
  background: rgba(17, 24, 22, 0.62);
  transition: border-color 0.2s var(--ease), background 0.2s var(--ease);
}

.page-about .team-card[open] {
  border-color: rgba(53, 224, 208, 0.55);
  background: rgba(23, 59, 54, 0.55);
}

.page-about .team-card summary {
  display: flex;
  align-items: flex-start;
  gap: 12px;
  padding: 14px 16px;
  cursor: pointer;
  list-style: none;
}

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

.page-about .team-card summary:focus-visible {
  outline: 1px solid var(--cyan);
  outline-offset: -2px;
}

.page-about .team-card__idx {
  padding-top: 3px;
  font-family: var(--font-mono);
  font-size: 11px;
  letter-spacing: 0.1em;
  color: var(--gold);
}

.page-about .team-card__head {
  display: block;
}

.page-about .team-card__name {
  margin: 0 0 4px;
  font-size: 16px;
  font-weight: 700;
  color: var(--mist);
}

.page-about .team-card__role {
  display: block;
  font-size: 13px;
  line-height: 1.6;
  color: var(--gray-cyan);
}

.page-about .team-card__sign {
  margin-left: auto;
  font-family: var(--font-mono);
  font-size: 17px;
  line-height: 1;
  color: var(--cyan);
  padding-top: 2px;
}

.page-about .team-card__sign::before {
  content: "+";
}

.page-about .team-card[open] .team-card__sign::before {
  content: "–";
}

.page-about .team-card__body {
  padding: 0 16px 16px 40px;
  font-size: 14px;
  line-height: 1.8;
  color: rgba(242, 247, 244, 0.78);
}

.page-about .team-card__body p {
  margin: 0;
}

.page-about .team-figure {
  margin-top: 16px;
}

/* 更新节奏 */
.page-about .rhythm {
  display: grid;
  gap: 0;
  margin-top: 6px;
  border-top: 1px solid var(--line);
}

.page-about .rhythm__row {
  display: grid;
  grid-template-columns: 1fr;
  gap: 4px;
  padding: 14px 0;
  border-bottom: 1px dashed rgba(140, 169, 161, 0.3);
}

.page-about .rhythm__time {
  font-family: var(--font-mono);
  font-size: 16px;
  letter-spacing: 0.03em;
  color: var(--gold);
}

.page-about .rhythm__label {
  font-size: 14px;
  line-height: 1.75;
  color: rgba(242, 247, 244, 0.8);
}

.page-about .rhythm__label strong {
  color: var(--mist);
  font-weight: 700;
}

/* 数据 */
.page-about .stats {
  display: grid;
  grid-template-columns: repeat(2, minmax(0, 1fr));
  gap: 10px;
  margin-top: 18px;
}

.page-about .stat {
  padding: 14px;
  border: 1px solid var(--line);
  background: rgba(30, 74, 63, 0.32);
  transition: border-color 0.18s var(--ease);
}

.page-about .stat:hover {
  border-color: var(--cyan);
}

.page-about .stat__num {
  display: block;
  font-family: var(--font-mono);
  font-size: 20px;
  letter-spacing: 0.01em;
  color: var(--cyan);
  line-height: 1.25;
}

.page-about .stat--gold .stat__num {
  color: var(--gold);
}

.page-about .stat__label {
  display: block;
  margin-top: 6px;
  font-size: 12.5px;
  line-height: 1.55;
  color: var(--gray-cyan);
}

/* 版本号入口 */
.page-about .entry {
  margin-top: 6px;
  padding: 18px;
  border: 1px solid rgba(229, 184, 92, 0.42);
  background: linear-gradient(142deg, rgba(229, 184, 92, 0.14), rgba(11, 42, 37, 0.3) 54%, rgba(53, 224, 208, 0.1));
}

.page-about .entry__tag {
  margin: 0 0 10px;
  font-family: var(--font-mono);
  font-size: 11px;
  letter-spacing: 0.2em;
  color: var(--gold-soft);
  text-transform: uppercase;
}

.page-about .entry__text {
  margin: 0;
  max-width: 60ch;
  font-size: 14.5px;
  line-height: 1.85;
  color: rgba(242, 247, 244, 0.85);
}

.page-about .entry__actions {
  display: flex;
  flex-wrap: wrap;
  gap: 10px;
  margin-top: 18px;
}

.page-about .entry__actions .btn {
  font-size: 13px;
  text-decoration: none;
  border-bottom: 0;
}

.page-about .entry__actions .btn--ghost {
  border-color: var(--line-strong);
  color: var(--mist);
}

.page-about .entry__actions .btn--ghost:hover,
.page-about .entry__actions .btn--ghost:focus-visible {
  border-color: var(--cyan);
  color: var(--cyan);
}

/* 平板及以上 */
@media (min-width: 640px) {
  .page-about .hero-facts {
    grid-template-columns: repeat(3, minmax(0, 1fr));
    gap: 16px;
  }

  .page-about .rhythm__row {
    grid-template-columns: 150px minmax(0, 1fr);
    gap: 18px;
    align-items: baseline;
  }

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

  .page-about .team-grid .team-card:first-child {
    grid-column: 1 / -1;
  }
}

@media (min-width: 900px) {
  .page-about .about-hero {
    padding: 26px 0 58px;
  }

  .page-about .about-hero__inner {
    grid-template-columns: minmax(0, 1.02fr) minmax(0, 0.98fr);
    gap: 46px;
  }

  .page-about .about-hero__lede {
    font-size: 16px;
  }

  .page-about .about-body {
    grid-template-columns: 208px minmax(0, 1fr);
    gap: 56px;
    padding: 46px 0 68px;
  }

  .page-about .about-toc {
    position: sticky;
    top: 24px;
    align-self: start;
  }

  .page-about .about-toc__list {
    flex-direction: column;
    gap: 0;
    overflow: visible;
    padding-bottom: 0;
  }

  .page-about .about-toc__list li {
    flex: 0 0 auto;
  }

  .page-about .about-toc__list a {
    width: 100%;
    padding: 8px 0 8px 13px;
    border: 0;
    border-left: 1px solid var(--line);
    font-size: 13.5px;
    background: transparent;
  }

  .page-about .about-toc__list a:hover,
  .page-about .about-toc__list a:focus-visible {
    border-left-color: var(--cyan);
    background: linear-gradient(90deg, rgba(53, 224, 208, 0.12), transparent);
  }

  .page-about .about-toc__cta {
    display: inline-flex;
    margin-top: 22px;
    font-size: 12.5px;
    text-decoration: none;
  }

  .page-about .about-section > p {
    font-size: 15.5px;
  }

  .page-about .versions {
    padding: 24px;
  }

  .page-about .versions__list {
    grid-template-columns: repeat(4, minmax(0, 1fr));
    gap: 14px;
  }

  .page-about .vstep::after {
    top: auto;
    bottom: -1px;
    left: -1px;
    width: calc(100% + 2px);
    height: 2px;
  }

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

  .page-about .team-grid .team-card:first-child {
    grid-column: auto;
  }

  .page-about .team-card__body {
    padding-left: 16px;
  }

  .page-about .stats {
    grid-template-columns: repeat(4, minmax(0, 1fr));
    gap: 12px;
  }

  .page-about .entry {
    padding: 26px 28px;
  }
}

@media (min-width: 1180px) {
  .page-about .about-body {
    grid-template-columns: 232px minmax(0, 1fr);
  }

  .page-about .about-section__title {
    font-size: 2rem;
  }
}

@media (prefers-reduced-motion: reduce) {
  .page-about .vstep,
  .page-about .vstep::after,
  .page-about .stat,
  .page-about .about-toc__list a,
  .page-about .team-card,
  .page-about .vstep__note {
    transition: none;
  }

  .page-about .vstep:hover,
  .page-about .vstep:focus-within {
    transform: none;
  }
}