.page-about {
  --about-chap: rgba(124, 135, 148, 0.24);
  --about-panel: rgba(245, 241, 232, 0.045);
  --about-flow-max: 68ch;
  position: relative;
  overflow-x: hidden;
  background: var(--ah-ink);
  color: var(--ah-body-text);
}

/* ---------- 首屏 ---------- */

.page-about .about-hero {
  position: relative;
  isolation: isolate;
  overflow: hidden;
  padding-block: clamp(26px, 5vw, 46px) clamp(40px, 7vw, 84px);
  background:
    radial-gradient(120% 90% at 86% 0%, rgba(79, 216, 208, 0.1), transparent 58%),
    linear-gradient(166deg, #0E2C24 0%, #12362B 34%, #0B1B2B 80%);
  border-bottom: 1px solid var(--ah-line);
}

.page-about .about-hero__slab {
  position: absolute;
  z-index: -1;
  top: -14%;
  right: -16%;
  width: min(780px, 70vw);
  height: 122%;
  background: linear-gradient(140deg, rgba(242, 169, 59, 0.17), rgba(242, 169, 59, 0.02) 62%);
  clip-path: polygon(36% 0, 100% 0, 100% 100%, 0 100%);
  pointer-events: none;
}

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

.page-about .ah-crumb {
  display: flex;
  align-items: center;
  gap: 8px;
  font-size: 12px;
  letter-spacing: 0.08em;
  color: var(--ah-stone);
}

.page-about .ah-crumb a {
  color: var(--ah-stone);
  text-decoration: none;
  transition: color 0.3s var(--ah-ease);
}

.page-about .ah-crumb a:hover,
.page-about .ah-crumb a:focus-visible {
  color: var(--ah-amber);
}

.page-about .about-crumb__sep {
  color: rgba(124, 135, 148, 0.55);
}

.page-about .about-crumb__here {
  color: rgba(245, 241, 232, 0.72);
}

.page-about .about-hero .ah-kicker {
  margin-top: clamp(22px, 4vw, 38px);
  color: var(--ah-amber);
}

.page-about .about-hero__title {
  margin: 14px 0 0;
  font-family: var(--ah-font-head);
  font-weight: 800;
  font-size: clamp(32px, 6.2vw, 60px);
  line-height: 1.1;
  letter-spacing: -0.02em;
  color: var(--ah-bone);
}

.page-about .about-hero__lede {
  margin: 20px 0 0;
  max-width: 54ch;
  font-size: 16.5px;
  line-height: 1.92;
  color: rgba(245, 241, 232, 0.76);
}

.page-about .about-figures {
  margin: clamp(28px, 5vw, 46px) 0 0;
  padding: 0;
  display: grid;
  grid-template-columns: repeat(3, minmax(0, 1fr));
  gap: 1px;
  max-width: 640px;
  background: rgba(245, 241, 232, 0.1);
  border: 1px solid rgba(245, 241, 232, 0.1);
  border-radius: var(--ah-radius);
  overflow: hidden;
}

.page-about .about-figures__item {
  padding: 14px 16px;
  background: rgba(11, 27, 43, 0.62);
}

.page-about .about-figures dt {
  font-size: 11px;
  letter-spacing: 0.12em;
  color: var(--ah-stone);
}

.page-about .about-figures dd {
  margin: 6px 0 0;
  font-family: var(--ah-font-mono);
  font-weight: 700;
  font-size: clamp(18px, 3.6vw, 30px);
  line-height: 1.06;
  color: var(--ah-amber);
  font-variant-numeric: tabular-nums;
}

/* ---------- 主体网格 ---------- */

.page-about .about-body {
  display: grid;
  grid-template-columns: 1fr;
  gap: clamp(28px, 5vw, 56px);
  padding-block: clamp(36px, 6vw, 76px) clamp(44px, 7vw, 96px);
}

/* ---------- 章节目录 ---------- */

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

.page-about .about-toc__label {
  margin: 0 0 12px;
  font-family: var(--ah-font-mono);
  font-size: 11px;
  letter-spacing: 0.16em;
  color: var(--ah-stone);
}

.page-about .about-toc__list {
  list-style: none;
  margin: 0;
  padding: 0;
  display: flex;
  gap: 8px;
  overflow-x: auto;
  padding-bottom: 8px;
  scrollbar-width: thin;
  scrollbar-color: rgba(124, 135, 148, 0.4) transparent;
}

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

.page-about .about-toc__link {
  display: flex;
  align-items: baseline;
  gap: 9px;
  padding: 9px 12px;
  border: 1px solid rgba(245, 241, 232, 0.1);
  border-radius: var(--ah-radius);
  background: var(--about-panel);
  color: rgba(245, 241, 232, 0.68);
  font-size: 13.5px;
  line-height: 1.4;
  text-decoration: none;
  white-space: nowrap;
  transition: color 0.3s var(--ah-ease), border-color 0.3s var(--ah-ease), background 0.3s var(--ah-ease);
}

.page-about .about-toc__link:hover,
.page-about .about-toc__link:focus-visible,
.page-about .about-toc__link.is-in {
  color: var(--ah-bone);
  border-color: rgba(242, 169, 59, 0.5);
  background: rgba(242, 169, 59, 0.1);
}

.page-about .about-toc__num {
  font-family: var(--ah-font-mono);
  font-size: 12px;
  font-weight: 700;
  color: var(--ah-amber);
  font-variant-numeric: tabular-nums;
}

/* ---------- 章节流 ---------- */

.page-about .about-flow {
  min-width: 0;
  display: flex;
  flex-direction: column;
  gap: clamp(44px, 7vw, 84px);
}

.page-about .about-chapter {
  scroll-margin-top: 132px;
}

.page-about .about-chapter__head {
  display: flex;
  align-items: flex-start;
  gap: clamp(12px, 2.4vw, 24px);
  padding-bottom: clamp(14px, 2vw, 20px);
  border-bottom: 1px solid var(--about-chap);
}

.page-about .about-chapter__num {
  flex: none;
  font-family: var(--ah-font-mono);
  font-weight: 700;
  font-size: clamp(38px, 7.6vw, 74px);
  line-height: 0.8;
  letter-spacing: -0.05em;
  color: rgba(124, 135, 148, 0.34);
  font-variant-numeric: tabular-nums;
  user-select: none;
}

.page-about .about-chapter__head-text {
  min-width: 0;
  padding-top: 4px;
}

.page-about .about-chapter__head-text .ah-kicker {
  color: var(--ah-cyan);
}

.page-about .about-chapter__head-text h2 {
  margin: 8px 0 0;
  font-family: var(--ah-font-serif);
  font-weight: 700;
  font-size: clamp(22px, 3.6vw, 34px);
  line-height: 1.3;
  letter-spacing: -0.01em;
  color: var(--ah-bone);
}

.page-about .about-chapter__body {
  display: grid;
  gap: clamp(20px, 3vw, 34px);
  padding-top: clamp(20px, 3vw, 32px);
}

.page-about .about-chapter__text p {
  margin: 0 0 1.15em;
  max-width: var(--about-flow-max);
  font-size: 16.5px;
  line-height: 1.95;
  color: var(--ah-body-text);
}

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

.page-about .about-chapter__ver {
  margin: clamp(22px, 3vw, 32px) 0 0;
  padding-top: 12px;
  border-top: 1px solid var(--about-chap);
  font-family: var(--ah-font-mono);
  font-size: 12px;
  letter-spacing: 0.1em;
  color: var(--ah-stone);
}

/* ---------- 配图 ---------- */

.page-about .about-figure {
  margin: 0;
  position: relative;
}

.page-about .about-figure img {
  display: block;
  width: 100%;
  height: auto;
  max-width: 100%;
  object-fit: cover;
  border-radius: var(--ah-radius);
  border: 1px solid rgba(245, 241, 232, 0.1);
  filter: saturate(0.86) contrast(1.04);
}

.page-about .about-figure__cap {
  display: block;
  margin-top: 10px;
  padding-left: 10px;
  border-left: 2px solid rgba(242, 169, 59, 0.55);
  font-size: 12px;
  letter-spacing: 0.08em;
  color: var(--ah-stone);
}

.page-about .about-figure--road {
  max-width: 620px;
}

/* ---------- 团队分组 ---------- */

.page-about .about-crew-grid {
  margin-top: clamp(20px, 3vw, 32px);
  display: grid;
  grid-template-columns: 1fr;
  gap: 10px;
}

.page-about .about-crew {
  border: 1px solid rgba(245, 241, 232, 0.12);
  border-radius: var(--ah-radius);
  background: var(--ah-glass);
  overflow: hidden;
  transition: border-color 0.3s var(--ah-ease), background 0.3s var(--ah-ease);
}

.page-about .about-crew:hover {
  border-color: rgba(79, 216, 208, 0.4);
}

.page-about .about-crew[open] {
  border-color: rgba(242, 169, 59, 0.42);
  background: rgba(242, 169, 59, 0.06);
}

.page-about .about-crew__summary {
  display: flex;
  align-items: center;
  gap: 12px;
  padding: 15px 18px;
  cursor: pointer;
  list-style: none;
}

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

.page-about .about-crew__summary::after {
  content: "+";
  margin-left: auto;
  font-family: var(--ah-font-mono);
  font-size: 18px;
  line-height: 1;
  color: var(--ah-amber);
}

.page-about .about-crew[open] .about-crew__summary::after {
  content: "\2212";
}

.page-about .about-crew__name {
  font-family: var(--ah-font-head);
  font-weight: 700;
  font-size: 17px;
  color: var(--ah-bone);
}

.page-about .about-crew__hint {
  font-size: 12px;
  letter-spacing: 0.06em;
  color: var(--ah-stone);
}

.page-about .about-crew__body {
  padding: 0 18px 18px;
  border-top: 1px solid rgba(245, 241, 232, 0.08);
  padding-top: 14px;
}

.page-about .about-crew__body p {
  margin: 0;
  font-size: 15px;
  line-height: 1.88;
  color: rgba(245, 241, 232, 0.72);
}

/* ---------- 更新节奏 ---------- */

.page-about .about-cadence {
  list-style: none;
  margin: 0;
  padding: 0;
  display: grid;
  grid-template-columns: 1fr;
  gap: 10px;
}

.page-about .about-cadence__item {
  padding: 16px 18px;
  border: 1px solid rgba(245, 241, 232, 0.12);
  border-radius: var(--ah-radius);
  background: var(--about-panel);
}

.page-about .about-cadence__item p {
  margin: 0;
  font-size: 14.5px;
  line-height: 1.8;
  color: rgba(245, 241, 232, 0.72);
}

.page-about .about-cadence__time {
  display: inline-block;
  margin-bottom: 8px;
  font-family: var(--ah-font-mono);
  font-size: 13px;
  font-weight: 700;
  letter-spacing: 0.1em;
  color: var(--ah-amber);
}

/* ---------- 发展历程时间轴 ---------- */

.page-about .about-timeline {
  overflow-x: auto;
  overscroll-behavior-x: contain;
  padding-bottom: 16px;
  scrollbar-width: thin;
  scrollbar-color: rgba(242, 169, 59, 0.45) transparent;
}

.page-about .about-timeline__track {
  list-style: none;
  margin: 0;
  padding: 0;
  display: flex;
  min-width: max-content;
}

.page-about .about-timeline__item {
  position: relative;
  flex: 0 0 auto;
  width: min(270px, 74vw);
  padding: 30px 22px 0 0;
  border-top: 2px solid rgba(124, 135, 148, 0.3);
}

.page-about .about-timeline__dot {
  position: absolute;
  top: -7px;
  left: 0;
  width: 12px;
  height: 12px;
  border-radius: 50%;
  background: var(--ah-amber);
  box-shadow: 0 0 0 4px rgba(242, 169, 59, 0.16);
}

.page-about .about-timeline__item--now .about-timeline__dot {
  background: var(--ah-cyan);
  box-shadow: 0 0 0 4px rgba(79, 216, 208, 0.18);
  animation: about-pulse 2s ease-in-out infinite;
}

@keyframes about-pulse {
  0%, 100% { box-shadow: 0 0 0 4px rgba(79, 216, 208, 0.18); }
  50% { box-shadow: 0 0 0 8px rgba(79, 216, 208, 0.06); }
}

.page-about .about-timeline__year {
  display: block;
  margin-bottom: 8px;
  font-family: var(--ah-font-mono);
  font-size: 20px;
  font-weight: 700;
  letter-spacing: 0.02em;
  color: var(--ah-amber);
  font-variant-numeric: tabular-nums;
}

.page-about .about-timeline__item--now .about-timeline__year {
  color: var(--ah-cyan);
}

.page-about .about-timeline__item h3 {
  margin: 0 0 8px;
  font-family: var(--ah-font-head);
  font-weight: 700;
  font-size: 16px;
  line-height: 1.4;
  color: var(--ah-bone);
}

.page-about .about-timeline__item p {
  margin: 0;
  font-size: 14px;
  line-height: 1.82;
  color: rgba(245, 241, 232, 0.66);
}

/* ---------- 内容原则 ---------- */

.page-about .about-principles {
  list-style: none;
  margin: 0;
  padding: 0;
}

.page-about .about-principles__item {
  display: grid;
  grid-template-columns: auto minmax(0, 1fr);
  gap: 16px;
  padding: 20px 0;
  border-top: 1px solid var(--about-chap);
}

.page-about .about-principles__item:last-child {
  border-bottom: 1px solid var(--about-chap);
}

.page-about .about-principles__num {
  font-family: var(--ah-font-serif);
  font-size: 22px;
  line-height: 1.2;
  color: rgba(242, 169, 59, 0.72);
}

.page-about .about-principles__body h3 {
  margin: 0 0 8px;
  font-family: var(--ah-font-head);
  font-weight: 700;
  font-size: 17px;
  line-height: 1.45;
  color: var(--ah-bone);
}

.page-about .about-principles__body p {
  margin: 0;
  max-width: 62ch;
  font-size: 15.5px;
  line-height: 1.9;
  color: rgba(245, 241, 232, 0.74);
}

/* ---------- 服务范围 ---------- */

.page-about .about-scope {
  padding: clamp(20px, 3vw, 30px);
  border: 1px solid rgba(79, 216, 208, 0.26);
  border-radius: var(--ah-radius);
  background: linear-gradient(150deg, rgba(18, 54, 43, 0.88), rgba(11, 27, 43, 0.9));
}

.page-about .about-scope__label {
  margin: 0 0 10px;
  font-family: var(--ah-font-mono);
  font-size: 11px;
  letter-spacing: 0.16em;
  color: var(--ah-cyan);
}

.page-about .about-scope__text {
  margin: 0;
  max-width: 66ch;
  font-size: 15.5px;
  line-height: 1.92;
  color: rgba(245, 241, 232, 0.82);
}

/* ---------- 延伸入口 ---------- */

.page-about .about-next {
  margin-top: clamp(8px, 2vw, 20px);
  padding: clamp(22px, 4vw, 36px);
  border: 1px solid rgba(242, 169, 59, 0.3);
  border-radius: var(--ah-radius);
  background: linear-gradient(150deg, rgba(122, 78, 29, 0.24), rgba(11, 27, 43, 0.9) 62%);
}

.page-about .about-next__title {
  margin: 0 0 18px;
  font-family: var(--ah-font-head);
  font-weight: 700;
  font-size: clamp(18px, 2.6vw, 22px);
  color: var(--ah-bone);
}

.page-about .about-next__list {
  list-style: none;
  margin: 0;
  padding: 0;
  display: grid;
  grid-template-columns: 1fr;
  gap: 1px;
  background: rgba(245, 241, 232, 0.1);
  border-radius: var(--ah-radius);
  overflow: hidden;
}

.page-about .about-next__item {
  display: flex;
  flex-direction: column;
  gap: 6px;
  padding: 15px 18px;
  background: rgba(11, 27, 43, 0.72);
  transition: background 0.3s var(--ah-ease);
}

.page-about .about-next__item:hover {
  background: rgba(242, 169, 59, 0.1);
}

.page-about .about-next__item a {
  font-family: var(--ah-font-head);
  font-weight: 700;
  font-size: 16px;
  color: var(--ah-amber);
  text-decoration: none;
}

.page-about .about-next__item a:hover,
.page-about .about-next__item a:focus-visible {
  color: var(--ah-cyan);
}

.page-about .about-next__item span {
  font-size: 13.5px;
  line-height: 1.7;
  color: rgba(245, 241, 232, 0.66);
}

/* ---------- 滚动显现 ---------- */

@keyframes about-reveal {
  from { opacity: 0; transform: translateY(18px); }
  to { opacity: 1; transform: none; }
}

@supports (animation-timeline: view()) {
  .page-about [data-reveal] {
    animation: about-reveal linear both;
    animation-timeline: view();
    animation-range: entry 8% entry 78%;
  }
}

/* ---------- 断点 ---------- */

@media (max-width: 640px) {
  .page-about .about-figures {
    grid-template-columns: 1fr;
    max-width: none;
  }

  .page-about .about-figures__item {
    display: flex;
    align-items: baseline;
    justify-content: space-between;
    gap: 12px;
  }

  .page-about .about-figures dt,
  .page-about .about-figures dd {
    margin: 0;
  }
}

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

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

  .page-about .about-cadence__item {
    border-radius: 0;
  }

  .page-about .about-cadence__item:first-child {
    border-radius: var(--ah-radius) 0 0 var(--ah-radius);
  }

  .page-about .about-cadence__item:last-child {
    border-radius: 0 var(--ah-radius) var(--ah-radius) 0;
  }

  .page-about .about-cadence__item + .about-cadence__item {
    border-left: 0;
  }

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

@media (min-width: 860px) {
  .page-about .about-chapter--with-figure .about-chapter__body {
    grid-template-columns: minmax(0, 1.2fr) minmax(0, 0.8fr);
    align-items: start;
  }
}

@media (min-width: 960px) {
  .page-about .about-body {
    grid-template-columns: 212px minmax(0, 1fr);
    gap: clamp(44px, 5vw, 80px);
    align-items: start;
  }

  .page-about .about-toc {
    position: sticky;
    top: clamp(88px, 13vh, 132px);
  }

  .page-about .about-toc__list {
    flex-direction: column;
    gap: 2px;
    overflow-x: visible;
    padding-bottom: 0;
  }

  .page-about .about-toc__link {
    border: 0;
    border-left: 2px solid rgba(124, 135, 148, 0.28);
    border-radius: 0;
    background: transparent;
    padding: 9px 10px 9px 14px;
    white-space: normal;
  }

  .page-about .about-toc__link:hover,
  .page-about .about-toc__link:focus-visible,
  .page-about .about-toc__link.is-in {
    border-left-color: var(--ah-amber);
    background: rgba(242, 169, 59, 0.08);
  }
}

@media (min-width: 1180px) {
  .page-about .about-next__list {
    grid-template-columns: repeat(4, minmax(0, 1fr));
  }
}

@media (prefers-reduced-motion: reduce) {
  .page-about .about-timeline__item--now .about-timeline__dot {
    animation: none;
  }

  .page-about [data-reveal] {
    animation: none;
  }
}