.page-about {
  --about-max: 1160px;
  --about-pad: clamp(18px, 4.5vw, 56px);
  --about-line: rgba(138, 153, 168, 0.42);
  --about-line-soft: rgba(138, 153, 168, 0.2);
  --about-sec-space: clamp(40px, 7vw, 92px);
  background: var(--paper);
  color: var(--ink);
  font-family: var(--font-body);
  line-height: 1.75;
}

.page-about .about-wrap {
  width: 100%;
  max-width: var(--about-max);
  margin-inline: auto;
  padding-inline: var(--about-pad);
}

.page-about h2 {
  font-family: var(--font-head);
  font-size: clamp(23px, 4.4vw, 38px);
  font-weight: 900;
  line-height: 1.24;
  letter-spacing: 0.06em;
  margin: 0 0 0.55em;
  max-width: 22ch;
}

.page-about h3 {
  font-family: var(--font-head);
  font-size: clamp(17px, 2.9vw, 21px);
  font-weight: 800;
  line-height: 1.4;
  letter-spacing: 0.04em;
  margin: 0 0 0.5em;
}

.page-about p {
  margin: 0 0 1em;
  max-width: 42em;
}

.page-about .about-sec-head {
  margin-bottom: clamp(22px, 4vw, 44px);
}

.page-about .about-sec-lede {
  font-size: clamp(15px, 2.2vw, 17px);
  color: var(--slate);
  max-width: 40em;
  margin-bottom: 0;
}

/* ---------- 首屏 ---------- */
.page-about .about-hero {
  position: relative;
  overflow: hidden;
  background: var(--ink);
  color: var(--paper);
  padding-block: clamp(26px, 5vw, 52px) clamp(36px, 6.5vw, 76px);
}

.page-about .about-hero::before {
  content: "";
  position: absolute;
  inset: 0;
  background: var(--ink-2);
  clip-path: polygon(58% 0, 100% 0, 100% 100%, 26% 100%);
  opacity: 0.9;
  pointer-events: none;
}

.page-about .about-hero::after {
  content: "";
  position: absolute;
  left: 0;
  right: 0;
  top: 68%;
  height: 1px;
  background: linear-gradient(90deg, transparent, var(--mint), transparent);
  opacity: 0.55;
  pointer-events: none;
}

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

.page-about .about-crumbs {
  display: flex;
  flex-wrap: wrap;
  align-items: center;
  gap: 8px;
  font-family: var(--font-mono);
  font-size: 12px;
  letter-spacing: 0.08em;
  color: var(--line);
  margin-bottom: clamp(18px, 3.5vw, 34px);
}

.page-about .about-crumbs a {
  color: var(--mist);
  text-decoration: none;
  border-bottom: 1px solid transparent;
}

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

.page-about .about-crumb-now {
  color: var(--paper);
}

.page-about .about-eyebrow {
  color: var(--mint);
  font-size: 12px;
  letter-spacing: 0.16em;
  margin-bottom: 14px;
}

.page-about .about-hero h1 {
  font-family: var(--font-head);
  font-size: clamp(29px, 6.4vw, 56px);
  font-weight: 900;
  line-height: 1.18;
  letter-spacing: 0.05em;
  margin: 0 0 clamp(16px, 3vw, 26px);
  max-width: 18ch;
  color: var(--paper);
}

.page-about .about-hero h1 .hl {
  color: var(--mint);
  box-shadow: inset 0 -0.18em 0 rgba(35, 230, 176, 0.22);
}

.page-about .about-lede {
  font-size: clamp(15px, 2.3vw, 18px);
  line-height: 1.8;
  color: rgba(244, 241, 232, 0.86);
  max-width: 40em;
}

.page-about .about-facts {
  list-style: none;
  margin: clamp(24px, 5vw, 46px) 0 0;
  padding: 0;
  display: grid;
  grid-template-columns: repeat(2, minmax(0, 1fr));
  gap: 1px;
  background: rgba(138, 153, 168, 0.4);
  border: 1px solid rgba(138, 153, 168, 0.4);
}

.page-about .about-facts li {
  background: var(--ink-2);
  padding: 14px 16px 16px;
  display: flex;
  flex-direction: column;
  gap: 4px;
  min-width: 0;
}

.page-about .fact-num {
  color: var(--mint);
  font-size: clamp(20px, 3.4vw, 26px);
  letter-spacing: 0.06em;
  line-height: 1.2;
}

.page-about .fact-label {
  font-size: 13px;
  line-height: 1.5;
  color: rgba(244, 241, 232, 0.78);
}

/* ---------- 三块业务 ---------- */
.page-about .about-origin {
  padding-block: var(--about-sec-space);
  background: var(--paper);
}

.page-about .origin-grid {
  display: grid;
  gap: clamp(22px, 4vw, 44px);
}

.page-about .origin-lead .eyebrow {
  color: var(--teal);
  font-size: 12px;
  letter-spacing: 0.14em;
  margin-bottom: 10px;
}

.page-about .origin-cards {
  list-style: none;
  margin: 0;
  padding: 0;
  display: grid;
  gap: clamp(12px, 2.2vw, 18px);
}

.page-about .origin-card {
  position: relative;
  background: var(--paper-2);
  border: 2px solid var(--ink);
  box-shadow: 6px 6px 0 rgba(7, 26, 43, 0.9);
  padding: clamp(16px, 3vw, 24px);
  overflow-wrap: anywhere;
}

.page-about .origin-card h3 {
  margin-top: 6px;
}

.page-about .origin-card p {
  margin-bottom: 0;
  font-size: 15px;
  color: var(--slate);
}

.page-about .origin-code {
  display: inline-block;
  font-size: 12px;
  letter-spacing: 0.14em;
  color: var(--teal);
  border-bottom: 2px solid var(--mint);
  padding-bottom: 2px;
}

/* ---------- 阶段档案 ---------- */
.page-about .about-timeline {
  background-color: var(--ink);
  background-image:
    linear-gradient(var(--about-line-soft) 1px, transparent 1px),
    linear-gradient(90deg, var(--about-line-soft) 1px, transparent 1px);
  background-size: 46px 46px;
  color: var(--paper);
  padding-block: var(--about-sec-space);
}

.page-about .about-timeline .eyebrow {
  color: var(--mint);
  font-size: 12px;
  letter-spacing: 0.14em;
  margin-bottom: 10px;
}

.page-about .about-timeline h2 {
  color: var(--paper);
}

.page-about .about-timeline .about-sec-lede {
  color: rgba(244, 241, 232, 0.76);
}

.page-about .tl-layout {
  display: grid;
  gap: clamp(18px, 3vw, 32px);
}

.page-about .tl-index {
  display: flex;
  gap: 8px;
  overflow-x: auto;
  padding-bottom: 6px;
  -webkit-overflow-scrolling: touch;
}

.page-about .tl-index-link {
  display: inline-flex;
  align-items: baseline;
  gap: 8px;
  flex: 0 0 auto;
  padding: 8px 12px;
  border: 1px solid var(--about-line);
  color: var(--paper);
  text-decoration: none;
  font-size: 13px;
  transition: border-color 0.22s var(--ease), background 0.22s var(--ease);
}

.page-about .tl-index-year {
  color: var(--mint);
  font-size: 13px;
  letter-spacing: 0.08em;
}

.page-about .tl-index-link:hover,
.page-about .tl-index-link:focus-visible {
  border-color: var(--mint);
  background: rgba(35, 230, 176, 0.12);
}

.page-about .tl-item {
  position: relative;
  background: var(--ink-2);
  border: 2px solid var(--about-line);
  padding: clamp(16px, 3.2vw, 26px);
  scroll-margin-top: 96px;
  transition: border-color 0.24s var(--ease), background 0.24s var(--ease);
}

.page-about .tl-item + .tl-item {
  margin-top: clamp(12px, 2vw, 18px);
}

.page-about .tl-item:hover,
.page-about .tl-item:target {
  border-color: var(--mint);
  background: var(--ink-3);
}

.page-about .tl-year {
  display: block;
  color: var(--mint);
  font-size: clamp(19px, 3.2vw, 25px);
  letter-spacing: 0.12em;
  line-height: 1.2;
  margin-bottom: 8px;
}

.page-about .tl-item h3 {
  color: var(--paper);
  margin-bottom: 0.45em;
}

.page-about .tl-item p {
  color: rgba(244, 241, 232, 0.8);
  font-size: 15px;
  margin-bottom: 12px;
}

.page-about .tl-tag {
  display: inline-block;
  font-family: var(--font-mono);
  font-size: 11px;
  letter-spacing: 0.12em;
  color: var(--ink);
  background: var(--amber);
  padding: 3px 9px;
}

.page-about .timeline-figure {
  margin: clamp(20px, 4vw, 34px) 0 0;
  max-width: 100%;
}

.page-about .timeline-figure img,
.page-about .e4fs-figure img,
.page-about .team-figure img {
  display: block;
  width: 100%;
  height: auto;
  object-fit: cover;
}

.page-about .media-caption {
  font-family: var(--font-mono);
  font-size: 11px;
  letter-spacing: 0.06em;
  color: var(--line);
  margin-top: 8px;
}

/* ---------- 区域网络 ---------- */
.page-about .about-regions {
  padding-block: var(--about-sec-space);
  background: var(--paper);
}

.page-about .about-regions .eyebrow {
  color: var(--teal);
  font-size: 12px;
  letter-spacing: 0.14em;
  margin-bottom: 10px;
}

.page-about .regions-body {
  display: grid;
  gap: clamp(20px, 3.5vw, 36px);
}

.page-about .region-map-wrap {
  border: 2px solid var(--ink);
  background:
    repeating-linear-gradient(90deg, transparent 0 22px, rgba(138, 153, 168, 0.14) 22px 23px),
    var(--paper-2);
  padding: clamp(8px, 2vw, 18px);
  box-shadow: 6px 6px 0 rgba(7, 26, 43, 0.14);
}

.page-about .region-map {
  display: block;
  width: 100%;
  height: auto;
}

.page-about .region-map .map-ring {
  fill: none;
  stroke: var(--about-line);
  stroke-dasharray: 3 7;
  stroke-width: 1;
}

.page-about .region-map .map-link {
  stroke: var(--teal);
  stroke-width: 1.5;
  stroke-dasharray: 5 5;
  opacity: 0.8;
}

.page-about .region-map .map-node {
  fill: var(--paper);
  stroke: var(--teal);
  stroke-width: 2;
}

.page-about .region-map .map-node--core {
  fill: var(--mint);
  stroke: var(--ink);
  stroke-width: 2.5;
}

.page-about .region-map .map-label {
  font-family: var(--font-mono);
  font-size: 13px;
  fill: var(--ink);
  letter-spacing: 0.04em;
}

.page-about .region-map .map-core-label {
  font-family: var(--font-mono);
  font-size: 12px;
  fill: var(--teal);
  letter-spacing: 0.06em;
}

.page-about .region-list {
  list-style: none;
  margin: 0;
  padding: 0;
  display: grid;
  gap: 10px;
}

.page-about .region-item {
  border: 1px solid var(--about-line);
  border-left: 4px solid var(--teal);
  background: rgba(191, 247, 234, 0.34);
  padding: 12px 14px 14px;
  display: grid;
  grid-template-columns: auto minmax(0, 1fr);
  grid-template-areas:
    "code name"
    "desc desc";
  column-gap: 10px;
  align-items: baseline;
}

.page-about .region-code {
  grid-area: code;
  font-size: 11px;
  letter-spacing: 0.1em;
  color: var(--teal);
}

.page-about .region-name {
  grid-area: name;
  font-size: 17px;
  margin: 0;
}

.page-about .region-desc {
  grid-area: desc;
  margin: 6px 0 0;
  font-size: 14px;
  line-height: 1.65;
  color: var(--slate);
}

/* ---------- 体验规范 ---------- */
.page-about .about-e4fs {
  padding-block: var(--about-sec-space);
  background: var(--paper-2);
  border-block: 2px solid var(--ink);
}

.page-about .about-e4fs .eyebrow {
  color: var(--teal);
  font-size: 12px;
  letter-spacing: 0.14em;
  margin-bottom: 10px;
}

.page-about .e4fs-grid {
  display: grid;
  gap: clamp(20px, 3.5vw, 36px);
}

.page-about .e4fs-item {
  border: 2px solid var(--ink);
  background: var(--paper);
}

.page-about .e4fs-item + .e4fs-item {
  margin-top: 10px;
}

.page-about .e4fs-item summary {
  display: flex;
  align-items: center;
  gap: 12px;
  padding: 13px 15px;
  cursor: pointer;
  list-style: none;
  font-family: var(--font-head);
  font-weight: 800;
  font-size: clamp(15px, 2.4vw, 17px);
  letter-spacing: 0.06em;
  transition: background 0.24s var(--ease), color 0.24s var(--ease);
}

.page-about .e4fs-item summary::-webkit-details-marker {
  display: none;
}

.page-about .e4fs-num {
  font-size: 12px;
  letter-spacing: 0.1em;
  color: var(--teal);
}

.page-about .e4fs-name {
  flex: 1 1 auto;
  min-width: 0;
}

.page-about .e4fs-mark {
  flex: 0 0 auto;
  width: 20px;
  height: 20px;
  display: inline-flex;
  align-items: center;
  justify-content: center;
  border: 1.5px solid currentColor;
  font-family: var(--font-mono);
  font-size: 13px;
  line-height: 1;
}

.page-about .e4fs-mark::after {
  content: "+";
}

.page-about .e4fs-item[open] .e4fs-mark::after {
  content: "−";
}

.page-about .e4fs-item[open] summary {
  background: var(--ink);
  color: var(--paper);
}

.page-about .e4fs-item[open] summary .e4fs-num {
  color: var(--mint);
}

.page-about .e4fs-item summary:hover,
.page-about .e4fs-item summary:focus-visible {
  background: var(--ink);
  color: var(--paper);
}

.page-about .e4fs-item summary:hover .e4fs-num,
.page-about .e4fs-item summary:focus-visible .e4fs-num {
  color: var(--mint);
}

.page-about .e4fs-body {
  padding: 14px 15px 16px;
  border-top: 2px solid var(--ink);
}

.page-about .e4fs-body p {
  margin: 0;
  font-size: 15px;
  color: var(--slate);
  max-width: 38em;
}

.page-about .e4fs-figure {
  margin: 0;
}

/* ---------- 团队 ---------- */
.page-about .about-team {
  padding-block: var(--about-sec-space);
  background: var(--slate);
  color: var(--paper);
}

.page-about .about-team .eyebrow {
  color: var(--mint);
  font-size: 12px;
  letter-spacing: 0.14em;
  margin-bottom: 10px;
}

.page-about .about-team h2 {
  color: var(--paper);
}

.page-about .team-grid {
  display: grid;
  gap: clamp(22px, 4vw, 40px);
}

.page-about .team-lede {
  color: rgba(244, 241, 232, 0.86);
  font-size: clamp(15px, 2.2vw, 17px);
}

.page-about .team-bars {
  margin-top: clamp(20px, 3.5vw, 32px);
  border-top: 1px solid rgba(244, 241, 232, 0.3);
  padding-top: 16px;
}

.page-about .team-bar-label {
  font-size: 12px;
  letter-spacing: 0.14em;
  color: var(--mint);
  margin-bottom: 10px;
}

.page-about .team-bar-track {
  display: grid;
  grid-template-columns: 5fr 7fr;
  gap: 3px;
  min-height: 52px;
}

.page-about .team-bar-seg {
  display: flex;
  align-items: center;
  padding: 8px 10px;
  font-family: var(--font-mono);
  font-size: 12px;
  line-height: 1.4;
  letter-spacing: 0.02em;
  border: 2px solid var(--paper);
  overflow-wrap: anywhere;
}

.page-about .team-bar-seg--a {
  background: var(--mint);
  color: var(--ink);
  font-weight: 700;
}

.page-about .team-bar-seg--b {
  background: transparent;
  color: var(--paper);
}

.page-about .team-rhythm {
  list-style: none;
  margin: clamp(22px, 4vw, 34px) 0 0;
  padding: 0;
  display: grid;
  gap: 0;
  border-top: 1px solid rgba(244, 241, 232, 0.3);
}

.page-about .rhythm-item {
  display: grid;
  gap: 4px;
  padding: 14px 0;
  border-bottom: 1px solid rgba(244, 241, 232, 0.3);
}

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

.page-about .rhythm-text {
  font-size: 15px;
  color: rgba(244, 241, 232, 0.88);
  line-height: 1.7;
}

.page-about .team-figure {
  margin: 0;
}

.page-about .about-team .media-caption {
  color: rgba(244, 241, 232, 0.6);
}

/* ---------- 协作与观察 ---------- */
.page-about .about-partners {
  padding-block: var(--about-sec-space);
  background: var(--paper);
}

.page-about .about-partners .eyebrow {
  color: var(--teal);
  font-size: 12px;
  letter-spacing: 0.14em;
  margin-bottom: 10px;
}

.page-about .partners-grid {
  display: grid;
  gap: clamp(22px, 4vw, 40px);
}

.page-about .partners-text p {
  color: var(--slate);
  font-size: 15px;
}

.page-about .partners-creed {
  position: relative;
  border: 2px solid var(--ink);
  background:
    repeating-linear-gradient(0deg, transparent 0 8px, rgba(7, 26, 43, 0.06) 8px 9px),
    var(--mist);
  padding: clamp(18px, 3.4vw, 30px);
  box-shadow: 7px 7px 0 rgba(7, 26, 43, 0.85);
  align-self: start;
}

.page-about .creed-kicker {
  font-size: 11px;
  letter-spacing: 0.2em;
  color: var(--teal);
  margin-bottom: 12px;
}

.page-about .creed-quote {
  margin: 0 0 14px;
  font-family: var(--font-head);
  font-size: clamp(18px, 3.2vw, 24px);
  font-weight: 800;
  line-height: 1.5;
  letter-spacing: 0.05em;
  color: var(--ink);
  border-left: 4px solid var(--orange);
  padding-left: 14px;
}

.page-about .creed-note {
  margin: 0;
  font-size: 14px;
  line-height: 1.7;
  color: var(--slate);
}

/* ---------- 下一步 ---------- */
.page-about .about-next {
  padding-block: var(--about-sec-space);
  background: var(--ink);
  color: var(--paper);
}

.page-about .about-next .eyebrow {
  color: var(--mint);
  font-size: 12px;
  letter-spacing: 0.14em;
  margin-bottom: 10px;
}

.page-about .about-next h2 {
  color: var(--paper);
}

.page-about .about-next .about-sec-lede {
  color: rgba(244, 241, 232, 0.76);
}

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

.page-about .next-card {
  border: 2px solid var(--about-line);
  background: rgba(16, 44, 66, 0.72);
  padding: clamp(16px, 3vw, 22px);
  display: flex;
  flex-direction: column;
  gap: 8px;
  transition: border-color 0.24s var(--ease), background 0.24s var(--ease);
}

.page-about .next-card:hover,
.page-about .next-card:focus-within {
  border-color: var(--mint);
  background: var(--ink-3);
}

.page-about .next-card-title {
  margin: 0;
  color: var(--paper);
  font-size: clamp(16px, 2.6vw, 19px);
}

.page-about .next-card-desc {
  margin: 0;
  font-size: 14px;
  line-height: 1.65;
  color: rgba(244, 241, 232, 0.76);
  flex: 1 1 auto;
}

.page-about .next-card-link {
  align-self: flex-start;
  font-family: var(--font-mono);
  font-size: 13px;
  letter-spacing: 0.08em;
  color: var(--mint);
  text-decoration: none;
  border-bottom: 1px solid var(--mint);
  padding-bottom: 2px;
}

.page-about .next-card-link:hover,
.page-about .next-card-link:focus-visible {
  color: var(--amber);
  border-bottom-color: var(--amber);
}

/* ---------- 响应式 ---------- */
@media (min-width: 600px) {
  .page-about .about-facts {
    grid-template-columns: repeat(4, minmax(0, 1fr));
  }

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

  .page-about .rhythm-item {
    grid-template-columns: 84px minmax(0, 1fr);
    align-items: baseline;
    column-gap: 14px;
  }
}

@media (min-width: 860px) {
  .page-about .tl-layout {
    grid-template-columns: 132px minmax(0, 1fr);
    align-items: start;
    column-gap: clamp(20px, 3vw, 36px);
  }

  .page-about .tl-index {
    position: sticky;
    top: 92px;
    flex-direction: column;
    overflow: visible;
    padding: 4px 0 4px 12px;
    border-left: 2px solid rgba(35, 230, 176, 0.4);
    gap: 4px;
  }

  .page-about .tl-index-link {
    border-color: transparent;
    padding: 8px 6px;
    justify-content: flex-start;
  }

  .page-about .tl-index-link:hover,
  .page-about .tl-index-link:focus-visible {
    border-color: var(--about-line);
  }

  .page-about .timeline-figure {
    max-width: 340px;
    margin-left: auto;
  }
}

@media (min-width: 960px) {
  .page-about .origin-grid {
    grid-template-columns: minmax(0, 0.88fr) minmax(0, 1.12fr);
    align-items: start;
    column-gap: clamp(28px, 4vw, 54px);
  }

  .page-about .origin-card:nth-child(2) {
    margin-left: clamp(0px, 2.4vw, 26px);
  }

  .page-about .regions-body {
    grid-template-columns: minmax(0, 1fr) minmax(0, 1fr);
    align-items: start;
  }

  .page-about .e4fs-grid {
    grid-template-columns: minmax(0, 1.08fr) minmax(0, 0.92fr);
    align-items: start;
  }

  .page-about .team-grid {
    grid-template-columns: minmax(0, 1.05fr) minmax(0, 0.95fr);
    align-items: start;
  }

  .page-about .partners-grid {
    grid-template-columns: minmax(0, 1.1fr) minmax(0, 0.9fr);
    align-items: start;
  }

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

@media (prefers-reduced-motion: reduce) {
  .page-about .tl-item,
  .page-about .e4fs-item summary,
  .page-about .next-card,
  .page-about .tl-index-link {
    transition: none;
  }
}