.page-about {
  --about-rail: 118px;
  --about-cut: 20px;
  --about-hair: rgba(201, 162, 39, 0.28);
}

/* ---------- 首屏 ---------- */
.page-about .about-hero {
  position: relative;
  background:
    radial-gradient(120% 90% at 12% 0%, rgba(47, 191, 168, 0.14) 0%, rgba(11, 27, 43, 0) 58%),
    radial-gradient(90% 70% at 92% 12%, rgba(201, 162, 39, 0.16) 0%, rgba(11, 27, 43, 0) 62%),
    var(--ky-ink);
  color: var(--ky-paper);
  padding: clamp(80px, 11vw, 128px) 0 clamp(44px, 6vw, 76px);
  overflow: hidden;
}

.page-about .about-hero__grid {
  position: absolute;
  inset: 0;
  background-image:
    linear-gradient(to right, rgba(245, 241, 232, 0.055) 1px, transparent 1px),
    linear-gradient(to bottom, rgba(245, 241, 232, 0.055) 1px, transparent 1px);
  background-size: 72px 72px;
  mask-image: linear-gradient(to bottom, rgba(0, 0, 0, 0.9), rgba(0, 0, 0, 0.15) 70%, transparent);
  -webkit-mask-image: linear-gradient(to bottom, rgba(0, 0, 0, 0.9), rgba(0, 0, 0, 0.15) 70%, transparent);
  pointer-events: none;
}

.page-about .about-hero__inner {
  position: relative;
  z-index: 1;
}

.page-about .about-hero .ky-breadcrumb__link,
.page-about .about-hero .ky-breadcrumb__sep,
.page-about .about-hero .ky-breadcrumb__current {
  color: var(--ky-gold-soft);
}

.page-about .about-hero__layout {
  display: grid;
  grid-template-columns: 1fr;
  gap: clamp(28px, 4vw, 48px);
  margin-top: clamp(28px, 4vw, 46px);
}

@media (min-width: 900px) {
  .page-about .about-hero__layout {
    grid-template-columns: minmax(0, 5fr) minmax(0, 7fr);
    align-items: end;
    gap: clamp(32px, 4vw, 60px);
  }
}

.page-about .about-hero h1 {
  font-family: var(--ky-serif);
  font-size: clamp(2.6rem, 7vw, 5.4rem);
  line-height: 1.02;
  letter-spacing: -0.015em;
  margin: 14px 0 0;
  color: var(--ky-paper);
}

.page-about .about-hero__lede {
  margin: 22px 0 0;
  max-width: 40ch;
  font-size: 1.0625rem;
  line-height: 1.85;
  color: rgba(245, 241, 232, 0.82);
}

.page-about .about-hero__facts {
  display: grid;
  grid-template-columns: repeat(2, minmax(0, 1fr));
  gap: 1px;
  margin: 30px 0 0;
  background: var(--ky-ink-line);
  border: 1px solid var(--ky-ink-line);
}

.page-about .about-hero__facts > div {
  background: rgba(18, 41, 63, 0.72);
  padding: 13px 16px;
}

.page-about .about-hero__facts dt {
  font-family: var(--ky-mono);
  font-size: 0.75rem;
  letter-spacing: 0.08em;
  color: var(--ky-gold-soft);
  text-transform: uppercase;
}

.page-about .about-hero__facts dd {
  margin: 6px 0 0;
  font-size: 0.95rem;
  color: var(--ky-paper);
}

.page-about .about-hero__figure {
  margin: 0;
  border: 1px solid var(--ky-ink-line);
  background: var(--ky-ink-panel);
  clip-path: polygon(0 0, 100% 0, 100% calc(100% - var(--about-cut)), calc(100% - var(--about-cut)) 100%, 0 100%);
}

.page-about .about-hero__figure img {
  display: block;
  width: 100%;
  height: auto;
  max-width: 100%;
  object-fit: cover;
  aspect-ratio: 16 / 7;
}

.page-about .about-hero__figure figcaption {
  padding: 12px 16px 14px;
  font-size: 0.8125rem;
  line-height: 1.6;
  color: rgba(245, 241, 232, 0.6);
  border-top: 1px solid var(--ky-ink-line);
}

/* ---------- 编年 ---------- */
.page-about .chronicle-grid {
  display: grid;
  grid-template-columns: 1fr;
  gap: clamp(20px, 3vw, 44px);
  margin-top: clamp(24px, 4vw, 44px);
}

@media (min-width: 860px) {
  .page-about .chronicle-grid {
    grid-template-columns: var(--about-rail) minmax(0, 1fr);
    align-items: start;
  }
  .page-about .chronicle-rail {
    position: sticky;
    top: 112px;
  }
}

.page-about .chronicle-rail__list {
  list-style: none;
  margin: 0;
  padding: 0;
  display: flex;
  flex-wrap: wrap;
  gap: 8px 18px;
}

@media (min-width: 860px) {
  .page-about .chronicle-rail__list {
    flex-direction: column;
    flex-wrap: nowrap;
    gap: 0;
    border-left: 1px solid var(--ky-paper-2);
    padding-left: 0;
  }
}

.page-about .chronicle-rail__list a {
  display: inline-flex;
  align-items: center;
  gap: 10px;
  font-family: var(--ky-mono);
  font-size: 0.9rem;
  letter-spacing: 0.04em;
  color: var(--ky-muted);
  text-decoration: none;
  padding: 7px 2px;
  transition: color 160ms var(--ky-ease);
}

@media (min-width: 860px) {
  .page-about .chronicle-rail__list a {
    margin-left: -1px;
    padding-left: 16px;
    position: relative;
  }
}

.page-about .chronicle-rail__tick {
  width: 10px;
  height: 10px;
  background: var(--ky-paper-2);
  clip-path: polygon(0 0, 100% 0, 100% 72%, 72% 100%, 0 100%);
  flex: none;
  transition: background 160ms var(--ky-ease);
}

@media (min-width: 860px) {
  .page-about .chronicle-rail__list a::before {
    content: "";
    position: absolute;
    left: -5px;
    top: 50%;
    width: 9px;
    height: 9px;
    transform: translateY(-50%) rotate(45deg);
    background: var(--ky-paper-2);
    transition: background 160ms var(--ky-ease);
  }
  .page-about .chronicle-rail__tick {
    display: none;
  }
}

.page-about .chronicle-rail__list a:hover,
.page-about .chronicle-rail__list a:focus-visible {
  color: var(--ky-gold);
}

.page-about .chronicle-rail__list a:hover .chronicle-rail__tick,
.page-about .chronicle-rail__list a:focus-visible .chronicle-rail__tick {
  background: var(--ky-gold);
}

@media (min-width: 860px) {
  .page-about .chronicle-rail__list a:hover::before,
  .page-about .chronicle-rail__list a:focus-visible::before {
    background: var(--ky-gold);
  }
}

.page-about .chronicle-stages {
  list-style: none;
  margin: 0;
  padding: 0;
  display: flex;
  flex-direction: column;
  gap: clamp(14px, 2vw, 22px);
}

.page-about .stage {
  position: relative;
  display: grid;
  grid-template-columns: 1fr;
  gap: 10px;
  background: var(--ky-paper);
  border: 1px solid var(--ky-paper-2);
  padding: clamp(20px, 3vw, 30px) clamp(20px, 3vw, 34px);
  clip-path: polygon(0 0, calc(100% - var(--about-cut)) 0, 100% var(--about-cut), 100% 100%, var(--about-cut) 100%, 0 calc(100% - var(--about-cut)));
  scroll-margin-top: 120px;
  transition: border-color 180ms var(--ky-ease);
}

.page-about .stage:hover {
  border-color: var(--ky-gold);
}

.page-about .stage__code {
  font-family: var(--ky-mono);
  font-size: 1.5rem;
  letter-spacing: 0.04em;
  color: var(--ky-gold);
  line-height: 1;
}

.page-about .stage__body {
  max-width: 60ch;
}

.page-about .stage__tag {
  margin: 0 0 10px;
}

.page-about .stage h3 {
  font-family: var(--ky-serif);
  font-size: clamp(1.15rem, 2vw, 1.4rem);
  line-height: 1.4;
  letter-spacing: -0.005em;
  color: var(--ky-ink);
  margin: 0 0 10px;
}

.page-about .stage p {
  margin: 0;
  color: var(--ky-text);
  line-height: 1.8;
  font-size: 0.975rem;
}

/* ---------- 目录 ---------- */
.page-about .catalog-layout {
  display: grid;
  grid-template-columns: 1fr;
  gap: clamp(24px, 4vw, 44px);
  margin-top: clamp(24px, 4vw, 40px);
}

@media (min-width: 940px) {
  .page-about .catalog-layout {
    grid-template-columns: minmax(0, 5fr) minmax(0, 7fr);
    align-items: start;
  }
}

.page-about .catalog-figure {
  margin: 0;
  border: 1px solid var(--ky-ink-line);
  background: var(--ky-ink-panel);
  clip-path: polygon(0 0, 100% 0, 100% 100%, var(--about-cut) 100%, 0 calc(100% - var(--about-cut)));
}

.page-about .catalog-figure img {
  display: block;
  width: 100%;
  height: auto;
  max-width: 100%;
  object-fit: cover;
  aspect-ratio: 4 / 3;
}

.page-about .catalog-figure figcaption {
  padding: 12px 16px 14px;
  font-size: 0.8125rem;
  line-height: 1.6;
  color: rgba(245, 241, 232, 0.62);
  border-top: 1px solid var(--ky-ink-line);
}

.page-about .catalog-tabs__list {
  display: grid;
  grid-template-columns: repeat(2, minmax(0, 1fr));
  gap: 8px;
  margin-bottom: 22px;
}

@media (min-width: 620px) {
  .page-about .catalog-tabs__list {
    grid-template-columns: repeat(3, minmax(0, 1fr));
  }
}

.page-about .catalog-tabs .ky-tabs__indicator {
  display: none;
}

.page-about .catalog-tab {
  appearance: none;
  border: 1px solid var(--ky-ink-line);
  background: transparent;
  color: rgba(245, 241, 232, 0.72);
  font-family: var(--ky-serif);
  font-size: 0.95rem;
  letter-spacing: 0.02em;
  padding: 13px 10px;
  cursor: pointer;
  text-align: center;
  clip-path: polygon(0 0, calc(100% - 12px) 0, 100% 12px, 100% 100%, 12px 100%, 0 calc(100% - 12px));
  transition: background 160ms var(--ky-ease), color 160ms var(--ky-ease), border-color 160ms var(--ky-ease);
}

.page-about .catalog-tab:hover {
  border-color: var(--ky-gold);
  color: var(--ky-paper);
}

.page-about .catalog-tab[aria-selected="true"] {
  background: var(--ky-gold);
  border-color: var(--ky-gold);
  color: var(--ky-ink);
}

.page-about .catalog-tab:focus-visible {
  outline: 2px solid var(--ky-gold-soft);
  outline-offset: 2px;
}

.page-about .catalog-tabs__panels {
  border-top: 1px solid var(--ky-ink-line);
  padding-top: 20px;
}

.page-about .catalog-panel__title {
  font-family: var(--ky-serif);
  font-size: 1.15rem;
  color: var(--ky-gold-soft);
  margin: 0 0 10px;
}

.page-about .catalog-tabs__panel p {
  margin: 0;
  color: rgba(245, 241, 232, 0.82);
  line-height: 1.85;
  max-width: 46ch;
  font-size: 0.975rem;
}

/* ---------- 三块式 ---------- */
.page-about .blocks-grid {
  display: grid;
  grid-template-columns: 1fr;
  gap: clamp(14px, 2vw, 22px);
  margin-top: clamp(24px, 4vw, 40px);
}

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

.page-about .block-card {
  position: relative;
  background: var(--ky-paper-2);
  border: 1px solid transparent;
  padding: clamp(20px, 3vw, 28px);
  clip-path: polygon(0 0, calc(100% - 22px) 0, 100% 22px, 100% 100%, 0 100%);
}

.page-about .block-card::after {
  content: "";
  position: absolute;
  left: 0;
  bottom: 0;
  width: 100%;
  height: 2px;
  background: linear-gradient(to right, var(--ky-gold), var(--ky-gold-soft));
  transform: scaleX(0);
  transform-origin: left center;
  transition: transform 220ms var(--ky-ease);
}

.page-about .block-card:hover::after,
.page-about .block-card:focus-within::after {
  transform: scaleX(1);
}

.page-about .block-card__code {
  display: inline-block;
  font-family: var(--ky-mono);
  font-size: 0.8rem;
  letter-spacing: 0.16em;
  color: var(--ky-cinnabar);
  margin-bottom: 12px;
}

.page-about .block-card h3 {
  font-family: var(--ky-serif);
  font-size: 1.2rem;
  color: var(--ky-ink);
  margin: 0 0 10px;
}

.page-about .block-card p {
  margin: 0;
  color: var(--ky-text);
  font-size: 0.95rem;
  line-height: 1.8;
}

.page-about .blocks-note {
  margin-top: clamp(22px, 3vw, 32px);
  border-left: 3px solid var(--ky-gold);
  padding: 4px 0 4px 20px;
}

.page-about .blocks-note p {
  margin: 0;
  color: var(--ky-text);
  line-height: 1.85;
  max-width: 68ch;
  font-size: 0.975rem;
}

.page-about .blocks-note a {
  color: var(--ky-ink);
  text-decoration: none;
  border-bottom: 1px solid var(--ky-gold);
  padding-bottom: 1px;
}

.page-about .blocks-note a:hover {
  color: var(--ky-gold);
}

/* ---------- 工序 ---------- */
.page-about .process-layout {
  display: grid;
  grid-template-columns: 1fr;
  gap: clamp(24px, 4vw, 46px);
  margin-top: clamp(24px, 4vw, 40px);
}

@media (min-width: 900px) {
  .page-about .process-layout {
    grid-template-columns: minmax(0, 5fr) minmax(0, 7fr);
    align-items: start;
  }
}

.page-about .process-figure {
  margin: 0;
  border: 1px solid var(--ky-ink-line);
  background: var(--ky-ink-panel);
  clip-path: polygon(0 0, 100% 0, calc(100% - var(--about-cut)) 100%, 0 100%);
}

.page-about .process-figure img {
  display: block;
  width: 100%;
  height: auto;
  max-width: 100%;
  object-fit: cover;
  aspect-ratio: 1 / 1;
}

.page-about .process-figure figcaption {
  padding: 12px 16px 14px;
  font-size: 0.8125rem;
  line-height: 1.6;
  color: rgba(245, 241, 232, 0.62);
  border-top: 1px solid var(--ky-ink-line);
}

.page-about .process-steps {
  list-style: none;
  margin: 0;
  padding: 0;
  display: flex;
  flex-direction: column;
}

.page-about .process-step {
  position: relative;
  padding: 0 0 clamp(20px, 3vw, 30px) 62px;
}

.page-about .process-step:last-child {
  padding-bottom: 0;
}

.page-about .process-step::before {
  content: "";
  position: absolute;
  left: 19px;
  top: 34px;
  bottom: 0;
  width: 1px;
  background: var(--ky-ink-line);
}

.page-about .process-step:last-child::before {
  display: none;
}

.page-about .process-step__no {
  position: absolute;
  left: 0;
  top: 0;
  width: 39px;
  height: 39px;
  display: grid;
  place-items: center;
  font-family: var(--ky-mono);
  font-size: 0.82rem;
  color: var(--ky-ink);
  background: var(--ky-gold);
  clip-path: polygon(0 0, 100% 0, 100% 72%, 72% 100%, 0 100%);
}

.page-about .process-step h3 {
  font-family: var(--ky-serif);
  font-size: 1.2rem;
  color: var(--ky-paper);
  margin: 6px 0 8px;
}

.page-about .process-step p {
  margin: 0;
  color: rgba(245, 241, 232, 0.78);
  font-size: 0.95rem;
  line-height: 1.82;
  max-width: 52ch;
}

.page-about .team-grid {
  display: grid;
  grid-template-columns: repeat(2, minmax(0, 1fr));
  gap: 1px;
  margin-top: clamp(30px, 5vw, 52px);
  background: var(--ky-ink-line);
  border: 1px solid var(--ky-ink-line);
}

@media (min-width: 760px) {
  .page-about .team-grid {
    grid-template-columns: repeat(4, minmax(0, 1fr));
  }
}

.page-about .team-cell {
  background: rgba(18, 41, 63, 0.7);
  padding: 20px 18px;
  display: flex;
  flex-direction: column;
  gap: 6px;
}

.page-about .team-cell--total {
  background: rgba(201, 162, 39, 0.12);
}

.page-about .team-cell__num {
  font-family: var(--ky-mono);
  font-size: 1.85rem;
  line-height: 1;
  color: var(--ky-gold-soft);
}

.page-about .team-cell__label {
  font-size: 0.85rem;
  color: rgba(245, 241, 232, 0.72);
  letter-spacing: 0.02em;
}

/* ---------- 版本 ---------- */
.page-about .versions-tabs {
  margin-top: clamp(24px, 4vw, 40px);
}

.page-about .versions-tabs__list {
  display: flex;
  flex-wrap: wrap;
  gap: 8px;
  border-bottom: 1px solid var(--ky-paper-2);
  padding-bottom: 0;
  margin-bottom: 22px;
}

.page-about .versions-tabs .ky-tabs__indicator {
  display: none;
}

.page-about .version-tab {
  appearance: none;
  background: transparent;
  border: 1px solid var(--ky-paper-2);
  border-bottom: none;
  color: var(--ky-muted);
  font-family: var(--ky-mono);
  font-size: 0.85rem;
  letter-spacing: 0.03em;
  padding: 11px 16px;
  cursor: pointer;
  clip-path: polygon(0 0, calc(100% - 12px) 0, 100% 12px, 100% 100%, 0 100%);
  transition: background 160ms var(--ky-ease), color 160ms var(--ky-ease), border-color 160ms var(--ky-ease);
}

.page-about .version-tab:hover {
  color: var(--ky-ink);
  border-color: var(--ky-gold);
}

.page-about .version-tab[aria-selected="true"] {
  background: var(--ky-ink);
  border-color: var(--ky-ink);
  color: var(--ky-gold-soft);
}

.page-about .version-tab:focus-visible {
  outline: 2px solid var(--ky-gold);
  outline-offset: 2px;
}

.page-about .versions-tabs__panels {
  background: var(--ky-paper);
  border: 1px solid var(--ky-paper-2);
  border-left: 3px solid var(--ky-gold);
  padding: clamp(20px, 3vw, 30px);
  clip-path: polygon(0 0, 100% 0, 100% 100%, 18px 100%, 0 calc(100% - 18px));
}

.page-about .version-panel__title {
  font-family: var(--ky-serif);
  font-size: 1.15rem;
  color: var(--ky-ink);
  margin: 0 0 10px;
}

.page-about .versions-tabs__panel p {
  margin: 0;
  color: var(--ky-text);
  line-height: 1.85;
  max-width: 58ch;
  font-size: 0.975rem;
}

.page-about .cadence {
  margin-top: clamp(30px, 4vw, 48px);
}

.page-about .cadence__title {
  font-family: var(--ky-serif);
  font-size: 1.15rem;
  color: var(--ky-ink);
  margin: 0 0 16px;
}

.page-about .cadence__list {
  list-style: none;
  margin: 0;
  padding: 0;
  display: grid;
  grid-template-columns: 1fr;
  gap: 1px;
  background: var(--ky-paper-2);
  border: 1px solid var(--ky-paper-2);
}

@media (min-width: 820px) {
  .page-about .cadence__list {
    grid-template-columns: repeat(3, minmax(0, 1fr));
  }
}

.page-about .cadence__list li {
  background: var(--ky-paper);
  padding: 20px 20px 22px;
  display: flex;
  flex-direction: column;
  gap: 10px;
}

.page-about .cadence__key {
  font-family: var(--ky-mono);
  font-size: 0.9rem;
  letter-spacing: 0.04em;
  color: var(--ky-cinnabar);
  border-bottom: 1px solid var(--ky-paper-2);
  padding-bottom: 8px;
  align-self: flex-start;
}

.page-about .cadence__text {
  color: var(--ky-text);
  font-size: 0.95rem;
  line-height: 1.8;
}

/* ---------- 范围 ---------- */
.page-about .reach-layout {
  display: grid;
  grid-template-columns: 1fr;
  gap: clamp(24px, 4vw, 44px);
  margin-top: clamp(20px, 3vw, 32px);
}

@media (min-width: 900px) {
  .page-about .reach-layout {
    grid-template-columns: minmax(0, 7fr) minmax(0, 5fr);
    align-items: start;
  }
}

.page-about .reach-copy p {
  margin: 0 0 18px;
  color: var(--ky-text);
  line-height: 1.88;
  max-width: 60ch;
  font-size: 0.975rem;
}

.page-about .reach-copy p:last-child {
  margin-bottom: 0;
}

.page-about .reach-side {
  display: flex;
  flex-direction: column;
  gap: 14px;
}

.page-about .reach-panel {
  background: var(--ky-paper-2);
  border-top: 2px solid var(--ky-ink);
  padding: 20px 22px 22px;
}

.page-about .reach-panel__title {
  font-family: var(--ky-serif);
  font-size: 1.05rem;
  color: var(--ky-ink);
  margin: 0 0 10px;
}

.page-about .reach-panel p {
  margin: 0;
  color: var(--ky-text);
  font-size: 0.925rem;
  line-height: 1.8;
}

.page-about .reach-panel__link {
  margin-top: 14px;
}

/* ---------- 延伸条 ---------- */
.page-about .more-strip {
  display: grid;
  grid-template-columns: 1fr;
  gap: clamp(20px, 3vw, 32px);
  background: var(--ky-ink);
  color: var(--ky-paper);
  padding: clamp(28px, 4vw, 44px) clamp(22px, 3.4vw, 44px);
  clip-path: polygon(0 0, calc(100% - 26px) 0, 100% 26px, 100% 100%, 26px 100%, 0 calc(100% - 26px));
}

@media (min-width: 880px) {
  .page-about .more-strip {
    grid-template-columns: minmax(0, 6fr) minmax(0, 6fr);
    align-items: center;
  }
}

.page-about .more-strip__title {
  font-family: var(--ky-serif);
  font-size: clamp(1.4rem, 2.6vw, 2rem);
  letter-spacing: -0.01em;
  color: var(--ky-paper);
  margin: 10px 0 12px;
}

.page-about .more-strip__text p {
  margin: 0;
  color: rgba(245, 241, 232, 0.76);
  line-height: 1.82;
  max-width: 48ch;
  font-size: 0.95rem;
}

.page-about .more-strip__links {
  display: flex;
  flex-wrap: wrap;
  gap: 10px;
}

.page-about .more-strip__links .ky-btn {
  flex: 1 1 auto;
  min-width: 168px;
  text-align: center;
}

@media (prefers-reduced-motion: reduce) {
  .page-about .block-card::after,
  .page-about .stage,
  .page-about .chronicle-rail__list a,
  .page-about .chronicle-rail__tick {
    transition: none;
  }
}