.page-about {
  --ab-pad: 20px;
  --ab-index: 112px;
  --ab-gap: 32px;
  --card-bg: var(--panel);
  --card-line: var(--grid);
  --card-text: #A9B2C2;
  background: var(--ink);
  color: var(--paper);
  overflow-x: clip;
}

@media (min-width: 720px) {
  .page-about {
    --ab-pad: 40px;
  }
}

@media (min-width: 1000px) {
  .page-about {
    --ab-gap: clamp(32px, 4vw, 64px);
  }
}

/* ---------- 首屏 ---------- */
.page-about .about-hero {
  padding-block: clamp(28px, 5vw, 56px) clamp(32px, 5vw, 64px);
  border-bottom: 1px solid var(--grid);
  background:
    radial-gradient(120% 140% at 88% -20%, rgba(0, 200, 255, 0.16), transparent 60%),
    radial-gradient(80% 120% at 4% 120%, rgba(255, 77, 0, 0.14), transparent 62%),
    var(--ink);
}

.page-about .about-hero .breadcrumb {
  margin-bottom: clamp(24px, 4vw, 40px);
  font-size: 12px;
}

.page-about .about-hero h1 {
  margin: 14px 0 0;
  max-width: 16ch;
  font-family: var(--font-display);
  font-size: clamp(34px, 7vw, 84px);
  font-weight: 200;
  line-height: 1.06;
  letter-spacing: -0.02em;
  color: var(--paper);
}

.page-about .about-hero .lede {
  margin: 22px 0 0;
  max-width: 52ch;
  font-size: clamp(15px, 1.5vw, 18px);
  line-height: 1.78;
  color: var(--paper-2);
}

.page-about .about-hero__facts {
  display: grid;
  grid-template-columns: repeat(2, minmax(0, 1fr));
  gap: 1px;
  margin: clamp(28px, 4vw, 44px) 0 0;
  padding: 0;
  background: var(--grid);
  border: 1px solid var(--grid);
}

@media (min-width: 720px) {
  .page-about .about-hero__facts {
    grid-template-columns: repeat(4, minmax(0, 1fr));
  }
}

.page-about .about-fact {
  background: var(--ink);
  padding: 16px 16px 18px;
}

.page-about .about-fact dt {
  margin-bottom: 8px;
  font-size: 11px;
  letter-spacing: 0.18em;
  color: var(--muted);
}

.page-about .about-fact dd {
  margin: 0;
  font-family: var(--font-mono);
  font-size: 30px;
  line-height: 1;
  letter-spacing: -0.01em;
  color: var(--paper);
}

.page-about .about-fact dd small {
  margin-left: 4px;
  font-family: var(--font-body);
  font-size: 12px;
  color: var(--muted);
}

/* ---------- 双栏骨架 ---------- */
.page-about .about-body {
  max-width: var(--maxw);
  margin: 0 auto;
  padding: 0 var(--ab-pad);
  display: grid;
  grid-template-columns: minmax(0, 1fr);
}

@media (min-width: 1000px) {
  .page-about .about-body {
    grid-template-columns: var(--ab-index) minmax(0, 1fr);
    column-gap: var(--ab-gap);
  }
}

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

@media (min-width: 1000px) {
  .page-about .about-index {
    display: block;
    position: sticky;
    top: 96px;
    align-self: start;
    padding-top: clamp(40px, 6vw, 78px);
  }
}

.page-about .about-index__caption {
  margin: 0 0 18px;
  font-size: 10px;
  letter-spacing: 0.2em;
  color: var(--muted);
}

.page-about .about-index__list {
  list-style: none;
  margin: 0;
  padding: 0;
  display: flex;
  flex-direction: column;
  gap: 12px;
}

.page-about .about-index__item {
  display: flex;
  flex-direction: column;
  gap: 2px;
  text-decoration: none;
  color: var(--muted);
}

.page-about .about-index__num {
  font-family: var(--font-display);
  font-size: 34px;
  font-weight: 200;
  line-height: 1;
  letter-spacing: -0.02em;
  color: var(--grid);
  transition: color 0.24s var(--ease);
}

.page-about .about-index__label {
  font-size: 10px;
  letter-spacing: 0.14em;
  color: var(--muted);
  transition: color 0.24s var(--ease);
}

.page-about .about-index__item:hover .about-index__num,
.page-about .about-index__item:focus-visible .about-index__num {
  color: var(--orange);
}

.page-about .about-index__item:hover .about-index__label,
.page-about .about-index__item:focus-visible .about-index__label {
  color: var(--paper);
}

/* ---------- 章节 ---------- */
.page-about .about-chapter {
  padding-block: clamp(40px, 6vw, 82px);
  border-top: 1px solid var(--grid);
}

.page-about .about-main > .about-chapter:first-child {
  border-top: 0;
}

@media (min-width: 1000px) {
  .page-about .about-chapter {
    scroll-margin-top: 96px;
  }
}

.page-about .about-chapter--light {
  --card-bg: #FFFFFF;
  --card-text: #4E5666;
  margin-inline: calc(-1 * var(--ab-pad));
  padding-inline: var(--ab-pad);
  background: var(--paper);
  color: var(--text-dark);
  border-top-color: var(--paper-2);
}

.page-about .about-chapter__kicker {
  display: flex;
  align-items: center;
  gap: 10px;
  margin: 0 0 14px;
  font-size: 12px;
  letter-spacing: 0.18em;
  color: var(--orange);
}

.page-about .about-chapter--light .about-chapter__kicker {
  color: var(--text-dark);
}

.page-about .about-chapter h2 {
  margin: 0;
  font-family: var(--font-display);
  font-size: clamp(26px, 4.4vw, 46px);
  font-weight: 200;
  line-height: 1.16;
  letter-spacing: -0.01em;
  color: var(--paper);
}

.page-about .about-chapter--light h2 {
  color: var(--text-dark);
}

.page-about .about-chapter__lede {
  margin: 16px 0 0;
  max-width: 62ch;
  font-size: 16px;
  line-height: 1.8;
  color: var(--muted);
}

.page-about .about-chapter--light .about-chapter__lede {
  color: #4E5666;
}

/* ---------- 资料卡 ---------- */
.page-about .about-cards {
  display: grid;
  grid-template-columns: minmax(0, 1fr);
  gap: 1px;
  margin-top: clamp(24px, 4vw, 40px);
  background: var(--card-line);
  border: 1px solid var(--card-line);
}

@media (min-width: 720px) {
  .page-about .about-cards {
    grid-template-columns: repeat(2, minmax(0, 1fr));
    align-items: start;
  }
}

.page-about .about-card {
  display: flex;
  flex-direction: column;
  gap: 10px;
  background: var(--card-bg);
  padding: 22px 20px 26px;
  transition: background 0.24s var(--ease), box-shadow 0.24s var(--ease);
}

@media (hover: hover) {
  .page-about .about-card:hover {
    background: #1B2230;
    box-shadow: inset 0 0 0 1px var(--arc);
  }
}

.page-about .about-card__figure {
  margin: -22px -20px 6px;
}

.page-about .about-card__meta {
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 12px;
  font-family: var(--font-mono);
  font-size: 11px;
  letter-spacing: 0.12em;
  color: var(--muted);
}

.page-about .about-card h3 {
  margin: 0;
  font-size: 20px;
  font-weight: 500;
  line-height: 1.4;
  color: var(--paper);
}

.page-about .about-card p {
  margin: 0;
  font-size: 15px;
  line-height: 1.78;
  color: var(--card-text);
}

.page-about .about-chapter--light .about-card h3 {
  color: var(--text-dark);
}

/* ---------- 工作流 ---------- */
.page-about .about-wire {
  display: block;
  width: 100%;
  height: 44px;
  margin-top: clamp(24px, 4vw, 36px);
  color: var(--grid);
}

.page-about .about-flow {
  list-style: none;
  margin: 8px 0 0;
  padding: 0 0 0 26px;
  position: relative;
}

.page-about .about-flow::before {
  content: "";
  position: absolute;
  left: 6px;
  top: 12px;
  bottom: 12px;
  width: 1px;
  background: var(--grid);
}

.page-about .about-flow > li {
  position: relative;
  margin-bottom: 12px;
}

.page-about .about-flow > li::before {
  content: "";
  position: absolute;
  left: -26px;
  top: 18px;
  width: 9px;
  height: 9px;
  background: var(--ink);
  border: 1px solid var(--orange);
  transform: rotate(45deg);
}

.page-about .about-flow__det {
  background: var(--panel);
  border-left: 2px solid var(--grid);
  transition: border-color 0.24s var(--ease);
}

.page-about .about-flow__det[open] {
  border-left-color: var(--orange);
}

.page-about .about-flow summary {
  display: flex;
  align-items: baseline;
  gap: 12px;
  padding: 15px 16px;
  cursor: pointer;
  list-style: none;
}

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

.page-about .about-flow__idx {
  font-size: 12px;
  letter-spacing: 0.14em;
  color: var(--orange);
}

.page-about .about-flow__name {
  font-size: 17px;
  font-weight: 500;
  color: var(--paper);
}

.page-about .about-flow__who {
  margin-left: auto;
  font-size: 11px;
  letter-spacing: 0.14em;
  color: var(--muted);
}

.page-about .about-flow__body {
  padding: 0 16px 16px;
}

.page-about .about-flow__body p {
  margin: 0;
  font-size: 15px;
  line-height: 1.8;
  color: var(--card-text);
}

/* ---------- 团队 ---------- */
.page-about .about-team__figure {
  margin: clamp(24px, 4vw, 36px) 0 0;
}

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

.page-about .about-team__grid {
  list-style: none;
  margin: clamp(20px, 3vw, 28px) 0 0;
  padding: 0;
  display: grid;
  grid-template-columns: minmax(0, 1fr);
  gap: 1px;
  background: var(--grid);
  border: 1px solid var(--grid);
}

@media (min-width: 640px) {
  .page-about .about-team__grid {
    grid-template-columns: repeat(2, minmax(0, 1fr));
  }
}

@media (min-width: 1100px) {
  .page-about .about-team__grid {
    grid-template-columns: repeat(4, minmax(0, 1fr));
  }
}

.page-about .about-team__grid > li {
  background: var(--panel);
  padding: 20px 18px 22px;
}

.page-about .about-team__num {
  display: block;
  font-size: 40px;
  line-height: 1;
  letter-spacing: -0.02em;
  color: var(--arc);
}

.page-about .about-team__role {
  display: block;
  margin: 8px 0 10px;
  font-size: 13px;
  letter-spacing: 0.16em;
  color: var(--paper);
}

.page-about .about-team__grid p {
  margin: 0;
  font-size: 14px;
  line-height: 1.75;
  color: var(--card-text);
}

.page-about .about-team__note {
  margin: 18px 0 0;
  padding-left: 14px;
  border-left: 2px solid var(--orange);
  font-size: 15px;
  line-height: 1.8;
  color: var(--muted);
}

/* ---------- 覆盖范围（浅色） ---------- */
.page-about .about-cover {
  display: grid;
  grid-template-columns: minmax(0, 1fr);
  gap: 24px;
  margin-top: clamp(24px, 4vw, 40px);
}

@media (min-width: 860px) {
  .page-about .about-cover {
    grid-template-columns: minmax(0, 1fr) minmax(0, 1.05fr);
    gap: 36px;
    align-items: start;
  }
}

.page-about .about-cover__nums {
  list-style: none;
  margin: 0 0 24px;
  padding: 0;
  display: grid;
  grid-template-columns: repeat(2, minmax(0, 1fr));
  gap: 1px;
  background: var(--paper-2);
  border: 1px solid var(--paper-2);
}

.page-about .about-cover__nums li {
  background: #FFFFFF;
  padding: 18px 16px 20px;
}

.page-about .about-cover__nums b {
  display: block;
  font-family: var(--font-mono);
  font-size: 44px;
  font-weight: 500;
  line-height: 1;
  color: var(--text-dark);
}

.page-about .about-cover__nums span {
  display: block;
  margin-top: 8px;
  font-size: 11px;
  letter-spacing: 0.16em;
  color: #6B7488;
}

.page-about .about-cover__list {
  list-style: none;
  margin: 0;
  padding: 0;
  display: grid;
  gap: 14px;
}

.page-about .about-cover__list li {
  display: grid;
  grid-template-columns: 76px minmax(0, 1fr);
  gap: 12px;
  padding-top: 14px;
  border-top: 1px solid var(--paper-2);
}

.page-about .about-cover__list b {
  font-size: 14px;
  font-weight: 500;
  letter-spacing: 0.06em;
  color: var(--text-dark);
}

.page-about .about-cover__list p {
  margin: 0;
  font-size: 15px;
  line-height: 1.75;
  color: #4E5666;
}

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

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

/* ---------- 里程碑年份轴 ---------- */
.page-about .about-years {
  list-style: none;
  display: flex;
  margin: clamp(24px, 4vw, 40px) 0 0;
  padding: 0;
  border: 1px solid var(--grid);
  overflow-x: auto;
  overscroll-behavior-x: contain;
  scroll-snap-type: x proximity;
}

.page-about .about-years > li {
  flex: 1 0 218px;
  background: var(--panel);
  border-left: 1px solid var(--grid);
  scroll-snap-align: start;
}

.page-about .about-years > li:first-child {
  border-left: 0;
}

.page-about .about-years__det[open] {
  background: #1B2230;
  box-shadow: inset 0 -2px 0 var(--orange);
}

.page-about .about-years summary {
  display: flex;
  flex-direction: column;
  gap: 8px;
  padding: 20px 18px 18px;
  cursor: pointer;
  list-style: none;
  position: relative;
}

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

.page-about .about-years summary::after {
  content: "+";
  position: absolute;
  top: 16px;
  right: 16px;
  font-family: var(--font-mono);
  font-size: 16px;
  color: var(--muted);
}

.page-about .about-years__det[open] summary::after {
  content: "–";
  color: var(--orange);
}

.page-about .about-years__year {
  font-size: 30px;
  line-height: 1;
  letter-spacing: -0.02em;
  color: var(--paper);
  transition: color 0.24s var(--ease);
}

.page-about .about-years__det[open] .about-years__year {
  color: var(--orange);
}

.page-about .about-years__title {
  font-size: 13px;
  line-height: 1.5;
  letter-spacing: 0.04em;
  color: var(--muted);
}

.page-about .about-years__body {
  padding: 0 18px 20px;
}

.page-about .about-years__body p {
  margin: 0;
  font-size: 14px;
  line-height: 1.78;
  color: var(--card-text);
}

/* ---------- 合作伙伴 ---------- */
.page-about .about-partners {
  display: grid;
  grid-template-columns: minmax(0, 1fr);
  gap: 1px;
  margin-top: clamp(24px, 4vw, 40px);
  background: var(--grid);
  border: 1px solid var(--grid);
}

@media (min-width: 760px) {
  .page-about .about-partners {
    grid-template-columns: repeat(2, minmax(0, 1fr));
    align-items: start;
  }
}

.page-about .about-partner {
  background: var(--panel);
  padding: 22px 20px 24px;
}

.page-about .about-partner__no {
  display: block;
  font-size: 12px;
  letter-spacing: 0.2em;
  color: var(--arc);
}

.page-about .about-partner h3 {
  margin: 10px 0 10px;
  font-size: 19px;
  font-weight: 500;
  line-height: 1.4;
  color: var(--paper);
}

.page-about .about-partner p {
  margin: 0;
  font-size: 15px;
  line-height: 1.78;
  color: var(--card-text);
}

/* ---------- 后续计划 ---------- */
.page-about .about-next-list {
  list-style: none;
  margin: clamp(24px, 4vw, 36px) 0 0;
  padding: 0;
  display: grid;
  gap: 1px;
  background: var(--grid);
  border: 1px solid var(--grid);
}

.page-about .about-next-list > li {
  display: grid;
  grid-template-columns: 40px minmax(0, 1fr);
  gap: 14px;
  background: var(--panel);
  padding: 20px 18px 22px;
}

.page-about .about-next-list__num {
  font-size: 14px;
  letter-spacing: 0.12em;
  color: var(--orange);
  padding-top: 3px;
}

.page-about .about-next-list h3 {
  margin: 0 0 8px;
  font-size: 18px;
  font-weight: 500;
  line-height: 1.4;
  color: var(--paper);
}

.page-about .about-next-list p {
  margin: 0;
  font-size: 15px;
  line-height: 1.78;
  color: var(--card-text);
}

.page-about .about-next-note {
  margin: 20px 0 0;
  max-width: 62ch;
  font-size: 15px;
  line-height: 1.8;
  color: var(--muted);
}

.page-about .about-next-links {
  display: grid;
  grid-template-columns: minmax(0, 1fr);
  gap: 1px;
  margin-top: clamp(24px, 4vw, 36px);
  background: var(--grid);
  border: 1px solid var(--grid);
}

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

.page-about .about-next-link {
  display: flex;
  flex-direction: column;
  gap: 6px;
  padding: 20px 18px 22px;
  background: var(--ink);
  text-decoration: none;
  border-left: 2px solid transparent;
  transition: background 0.24s var(--ease), border-color 0.24s var(--ease);
}

.page-about .about-next-link:hover,
.page-about .about-next-link:focus-visible {
  background: #1B2230;
  border-left-color: var(--orange);
}

.page-about .about-next-link__label {
  font-size: 15px;
  font-weight: 500;
  letter-spacing: 0.06em;
  color: var(--paper);
}

.page-about .about-next-link__desc {
  font-size: 13px;
  line-height: 1.6;
  color: var(--muted);
}