.page-about {
  --about-gap: clamp(56px, 8vw, 104px);
  --about-radius-a: 12px;
  --about-radius-b: 24px;
  background: var(--paper);
  color: var(--graphite);
  overflow-x: hidden;
}

.page-about img {
  max-width: 100%;
  height: auto;
}

.page-about a:focus-visible,
.page-about summary:focus-visible,
.page-about li:focus-visible {
  outline: 2px solid var(--chip);
  outline-offset: 3px;
  border-radius: 6px;
}

/* ---------- 按钮 ---------- */
.page-about .btn {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  min-height: 44px;
  padding: 11px 22px;
  border-radius: 999px;
  border: 2px solid transparent;
  font-size: 14px;
  font-weight: 700;
  text-decoration: none;
  transition: background-color 200ms var(--ease), color 200ms var(--ease), border-color 200ms var(--ease);
}

.page-about .btn--primary {
  background: var(--chip);
  border-color: var(--chip);
  color: var(--paper);
}

.page-about .btn--primary:hover {
  background: var(--gold);
  border-color: var(--gold);
  color: var(--ink);
}

.page-about .btn--outline {
  background: transparent;
  border-color: var(--table);
  color: var(--table);
}

.page-about .btn--outline:hover {
  background: var(--table);
  border-color: var(--table);
  color: var(--paper);
}

/* ---------- 首屏 ---------- */
.page-about .about-hero {
  position: relative;
  overflow: hidden;
  background: var(--table);
  color: var(--paper);
  padding: clamp(24px, 4vw, 38px) 0 clamp(56px, 9vw, 96px);
  border-bottom: 4px solid var(--chip);
}

.page-about .about-hero::before {
  content: "";
  position: absolute;
  inset: 0;
  background:
    radial-gradient(circle at 86% 10%, rgba(216, 169, 75, 0.16), transparent 46%),
    radial-gradient(circle at 6% 92%, rgba(26, 90, 74, 0.92), transparent 58%);
  pointer-events: none;
}

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

.page-about .breadcrumbs {
  display: flex;
  align-items: center;
  gap: 8px;
  font-size: 13px;
  color: rgba(247, 245, 239, 0.7);
  margin-bottom: clamp(26px, 4vw, 44px);
}

.page-about .breadcrumbs__link {
  color: rgba(247, 245, 239, 0.7);
  text-decoration: none;
  transition: color 200ms var(--ease);
}

.page-about .breadcrumbs__link:hover {
  color: var(--chip);
}

.page-about .breadcrumbs__sep {
  color: rgba(247, 245, 239, 0.36);
}

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

.page-about .about-hero__grid {
  display: grid;
  gap: clamp(34px, 6vw, 60px);
}

@media (min-width: 900px) {
  .page-about .about-hero__grid {
    grid-template-columns: minmax(0, 1.35fr) minmax(0, 0.85fr);
    align-items: end;
  }
}

.page-about .about-hero .kicker {
  margin: 0;
  color: var(--chip);
  font-size: 13px;
  font-weight: 700;
  letter-spacing: 0.2em;
}

.page-about .about-hero__title {
  margin: 14px 0 20px;
  max-width: 14em;
  font-family: var(--font-display);
  font-size: clamp(30px, 5.4vw, 56px);
  font-weight: 900;
  line-height: 1.16;
  letter-spacing: -0.02em;
  color: var(--paper);
}

.page-about .about-hero__lead {
  margin: 0;
  max-width: 34em;
  font-size: clamp(15px, 1.6vw, 17px);
  line-height: 1.82;
  color: rgba(247, 245, 239, 0.84);
}

.page-about .about-hero__actions {
  display: flex;
  flex-wrap: wrap;
  gap: 12px;
  margin-top: clamp(24px, 3.4vw, 34px);
}

.page-about .about-hero .btn--outline {
  color: var(--paper);
  border-color: rgba(247, 245, 239, 0.55);
}

.page-about .about-hero .btn--outline:hover {
  background: var(--paper);
  border-color: var(--paper);
  color: var(--table);
}

.page-about .about-hero__board {
  position: relative;
  overflow: hidden;
  min-height: 236px;
  padding: clamp(24px, 5vw, 34px);
  display: flex;
  flex-direction: column;
  justify-content: flex-end;
  background: linear-gradient(158deg, rgba(26, 90, 74, 0.95), rgba(8, 16, 14, 0.98));
  border: 2px solid rgba(216, 169, 75, 0.42);
  clip-path: polygon(0 0, 100% 0, 100% 84%, 84% 100%, 0 100%);
}

.page-about .about-hero__chip {
  position: absolute;
  border-radius: 50%;
  background: var(--chip);
  box-shadow: inset 0 0 0 5px rgba(8, 16, 14, 0.45);
}

.page-about .about-hero__chip--a {
  width: 58px;
  height: 58px;
  top: 20px;
  right: 26px;
}

.page-about .about-hero__chip--b {
  width: 34px;
  height: 34px;
  top: 48px;
  right: 92px;
  background: var(--gold);
  box-shadow: inset 0 0 0 4px rgba(8, 16, 14, 0.4);
}

.page-about .about-hero__chip--c {
  width: 20px;
  height: 20px;
  top: 94px;
  right: 38px;
  background: var(--sand);
  box-shadow: inset 0 0 0 3px rgba(8, 16, 14, 0.35);
}

.page-about .about-hero__board-face {
  position: relative;
}

.page-about .about-hero__board-kicker {
  margin: 0 0 4px;
  font-family: var(--font-mono);
  font-size: 11px;
  letter-spacing: 0.22em;
  color: var(--gold);
}

.page-about .about-hero__board-num {
  margin: 0;
  font-family: var(--font-mono);
  font-variant-numeric: tabular-nums;
  font-size: clamp(56px, 11vw, 92px);
  font-weight: 700;
  line-height: 0.92;
  letter-spacing: -0.04em;
  color: var(--chip);
}

.page-about .about-hero__board-unit {
  margin: 6px 0 0;
  font-size: 13px;
  letter-spacing: 0.08em;
  color: rgba(247, 245, 239, 0.74);
}

/* ---------- 章节索引 ---------- */
.page-about .about-index {
  background: var(--paper);
  border-bottom: 2px solid var(--sand);
  padding: 16px 0;
}

.page-about .about-index__list {
  display: flex;
  gap: 8px;
  margin: 0;
  padding: 0 0 4px;
  list-style: none;
  overflow-x: auto;
  -webkit-overflow-scrolling: touch;
  scrollbar-width: thin;
}

.page-about .about-index__link {
  display: inline-flex;
  align-items: center;
  gap: 8px;
  padding: 9px 15px;
  border: 1px solid var(--sand);
  border-radius: 999px;
  font-size: 13px;
  color: var(--graphite);
  text-decoration: none;
  white-space: nowrap;
  transition: border-color 200ms var(--ease), background-color 200ms var(--ease), color 200ms var(--ease);
}

.page-about .about-index__link:hover,
.page-about .about-index__link:focus-visible {
  border-color: var(--chip);
  background: rgba(232, 114, 43, 0.08);
  color: var(--table);
}

.page-about .about-index__num {
  font-family: var(--font-mono);
  font-variant-numeric: tabular-nums;
  font-weight: 700;
  color: var(--chip);
}

/* ---------- 章节通用 ---------- */
.page-about .about-chapter {
  padding-block: var(--about-gap);
}

.page-about .about-chapter--sand {
  background: var(--sand);
}

.page-about .about-chapter--dark {
  background: var(--table);
  color: var(--paper);
}

.page-about .about-band {
  height: 4px;
  background: linear-gradient(90deg, var(--chip), var(--gold) 62%, var(--sand));
}

.page-about .about-chapter__head {
  display: grid;
  grid-template-columns: auto minmax(0, 1fr);
  column-gap: clamp(14px, 3vw, 24px);
  align-items: start;
  margin-bottom: clamp(28px, 5vw, 54px);
}

.page-about .about-chapter__head .section-number {
  font-family: var(--font-mono);
  font-variant-numeric: tabular-nums;
  font-size: clamp(44px, 9vw, 96px);
  font-weight: 700;
  line-height: 0.86;
  letter-spacing: -0.05em;
  color: var(--sand);
  transition: color 320ms var(--ease);
}

.page-about .about-chapter--sand .about-chapter__head .section-number {
  color: rgba(14, 59, 50, 0.2);
}

.page-about .about-chapter--dark .about-chapter__head .section-number {
  color: rgba(247, 245, 239, 0.24);
}

.page-about .about-chapter__head .section-number.is-active {
  color: var(--chip);
}

.page-about .about-chapter__heading h2 {
  margin: 0 0 10px;
  font-family: var(--font-display);
  font-size: clamp(24px, 3.6vw, 40px);
  font-weight: 900;
  line-height: 1.22;
  letter-spacing: -0.02em;
  color: var(--table);
}

.page-about .about-chapter--dark .about-chapter__heading h2 {
  color: var(--paper);
}

.page-about .about-chapter__sub {
  margin: 0;
  max-width: 40em;
  font-size: clamp(14px, 1.5vw, 16px);
  line-height: 1.8;
  color: var(--fog);
}

.page-about .about-chapter--dark .about-chapter__sub {
  color: rgba(247, 245, 239, 0.74);
}

.page-about .about-chapter__head .vertical-note {
  display: none;
}

@media (min-width: 1024px) {
  .page-about .about-chapter__head {
    grid-template-columns: auto minmax(0, 1fr) auto;
  }

  .page-about .about-chapter__head .vertical-note {
    display: block;
    writing-mode: vertical-rl;
    padding-top: 8px;
    font-size: 12px;
    letter-spacing: 0.3em;
    color: var(--fog);
  }

  .page-about .about-chapter--dark .about-chapter__head .vertical-note {
    color: rgba(247, 245, 239, 0.5);
  }
}

.page-about .about-chapter__body {
  display: grid;
  gap: clamp(28px, 5vw, 44px);
}

@media (min-width: 1024px) {
  .page-about .about-chapter__body {
    grid-template-columns: minmax(0, 1fr) minmax(0, 300px);
    align-items: start;
  }
}

.page-about .about-figure {
  margin: 0 0 clamp(26px, 4vw, 42px);
  border: 2px solid var(--table);
  border-radius: var(--about-radius-b) var(--about-radius-a) var(--about-radius-b) var(--about-radius-a);
  overflow: hidden;
  background: var(--cloth);
}

.page-about .about-chapter--dark .about-figure {
  border-color: var(--gold);
}

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

.page-about .about-figure__cap {
  padding: 12px 16px;
  font-size: 12px;
  line-height: 1.7;
  color: var(--fog);
  background: var(--paper);
}

.page-about .about-chapter__aside .about-figure {
  margin-bottom: 14px;
}

.page-about .annotation {
  margin: 0;
  padding-left: 12px;
  border-left: 2px solid var(--gold);
  font-size: 13px;
  line-height: 1.78;
  color: var(--fog);
}

.page-about .annotation__label {
  display: inline-block;
  margin-right: 6px;
  font-family: var(--font-mono);
  font-size: 11px;
  letter-spacing: 0.12em;
  color: var(--chip);
}

.page-about .about-quote {
  margin: clamp(28px, 4vw, 44px) 0 0;
  max-width: 46em;
  padding: 18px 22px;
  background: var(--sand);
  border-left: 4px solid var(--chip);
  border-radius: 0 var(--about-radius-a) var(--about-radius-a) 0;
  font-size: clamp(15px, 1.6vw, 17px);
  font-weight: 700;
  line-height: 1.7;
  color: var(--table);
}

.page-about .about-chapter--sand .about-quote {
  background: var(--paper);
}

.page-about .about-chapter--dark .about-quote {
  background: rgba(247, 245, 239, 0.08);
  color: var(--paper);
}

.page-about .about-lead {
  margin: clamp(22px, 3vw, 30px) 0 0;
  max-width: 46em;
  font-size: clamp(14px, 1.5vw, 16px);
  line-height: 1.85;
  color: var(--graphite);
}

.page-about .about-chapter--dark .about-lead {
  color: rgba(247, 245, 239, 0.8);
}

/* ---------- 时间轴 ---------- */
.page-about .about-timeline {
  position: relative;
  list-style: none;
  margin: 0;
  padding: 0;
  display: grid;
  gap: 16px;
}

.page-about .about-timeline::before {
  content: "";
  position: absolute;
  left: 26px;
  top: 26px;
  bottom: 26px;
  width: 2px;
  background: linear-gradient(180deg, var(--gold), var(--sand));
}

.page-about .about-timeline__node {
  position: relative;
  padding: 18px 20px 18px 56px;
  background: var(--sand);
  border: 1px solid var(--sand);
  border-radius: var(--about-radius-a) var(--about-radius-b) var(--about-radius-b) var(--about-radius-a);
  transition: transform 200ms var(--ease), border-color 200ms var(--ease);
}

.page-about .about-timeline__node:hover,
.page-about .about-timeline__node:focus-visible {
  transform: translateY(-2px);
  border-color: var(--chip);
}

.page-about .about-timeline__dot {
  position: absolute;
  left: 20px;
  top: 24px;
  width: 14px;
  height: 14px;
  border-radius: 50%;
  background: var(--gold);
  box-shadow: 0 0 0 4px rgba(216, 169, 75, 0.24);
  transition: background-color 200ms var(--ease), box-shadow 200ms var(--ease);
}

.page-about .about-timeline__node:hover .about-timeline__dot,
.page-about .about-timeline__node:focus-visible .about-timeline__dot {
  background: var(--chip);
  box-shadow: 0 0 0 6px rgba(232, 114, 43, 0.24);
}

.page-about .about-timeline__season {
  display: inline-block;
  margin-bottom: 10px;
  padding: 3px 10px;
  border-radius: 999px;
  background: rgba(232, 114, 43, 0.12);
  font-family: var(--font-mono);
  font-variant-numeric: tabular-nums;
  font-size: 12px;
  letter-spacing: 0.1em;
  color: var(--chip);
}

.page-about .about-timeline__title {
  margin: 0 0 8px;
  font-family: var(--font-display);
  font-size: clamp(17px, 2vw, 20px);
  font-weight: 700;
  color: var(--table);
}

.page-about .about-timeline__note {
  margin: 0;
  font-size: 14px;
  line-height: 1.8;
  color: var(--graphite);
}

/* ---------- 折叠面板 ---------- */
.page-about .about-more {
  margin-top: 26px;
  background: var(--paper);
  border: 1px solid var(--sand);
  border-radius: var(--about-radius-b) var(--about-radius-a) var(--about-radius-b) var(--about-radius-a);
  overflow: hidden;
}

.page-about .about-more .fold__summary {
  display: flex;
  align-items: center;
  gap: 10px;
  padding: 16px 20px;
  cursor: pointer;
  list-style: none;
  font-size: 15px;
  font-weight: 700;
  color: var(--table);
}

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

.page-about .about-more .fold__summary::before {
  content: "＋";
  font-family: var(--font-mono);
  font-size: 16px;
  color: var(--chip);
}

.page-about .about-more[open] .fold__summary::before {
  content: "－";
}

.page-about .about-more .fold__body {
  padding: 0 20px 22px;
}

.page-about .about-more__list {
  margin: 0;
  padding-left: 20px;
  display: grid;
  gap: 12px;
  font-size: 14px;
  line-height: 1.8;
  color: var(--graphite);
}

.page-about .about-more__list strong {
  color: var(--table);
}

/* ---------- 三条做法 ---------- */
.page-about .about-principles {
  display: grid;
  gap: 18px;
}

.page-about .about-principle {
  position: relative;
  padding: clamp(22px, 3vw, 30px);
  background: var(--paper);
  border: 2px solid var(--table);
  border-radius: var(--about-radius-b) var(--about-radius-a) var(--about-radius-b) var(--about-radius-a);
  transition: transform 200ms var(--ease);
}

.page-about .about-principle::before {
  content: "";
  position: absolute;
  left: 0;
  top: 24px;
  bottom: 24px;
  width: 3px;
  border-radius: 3px;
  background: var(--chip);
  opacity: 0;
  transition: opacity 200ms var(--ease);
}

.page-about .about-principle::after {
  content: "";
  position: absolute;
  top: 22px;
  right: 22px;
  width: 12px;
  height: 12px;
  border-radius: 50%;
  background: var(--chip);
}

.page-about .about-principle:hover {
  transform: translateY(-2px);
}

.page-about .about-principle:hover::before {
  opacity: 1;
}

.page-about .about-principle__title {
  margin: 0 0 12px;
  padding-right: 26px;
  font-family: var(--font-display);
  font-size: clamp(18px, 2vw, 21px);
  font-weight: 900;
  letter-spacing: -0.01em;
  color: var(--table);
}

.page-about .about-principle p {
  margin: 0;
  font-size: 14px;
  line-height: 1.82;
  color: var(--graphite);
}

.page-about .about-principle__scene {
  margin-top: 16px !important;
  padding: 12px 14px;
  background: var(--sand);
  border-radius: var(--about-radius-a);
  font-size: 13px !important;
  line-height: 1.75 !important;
  color: var(--graphite);
}

@media (min-width: 880px) {
  .page-about .about-principles {
    grid-template-columns: repeat(3, minmax(0, 1fr));
    align-items: start;
    padding-bottom: 68px;
  }

  .page-about .about-principle:nth-child(2) {
    margin-top: 34px;
  }

  .page-about .about-principle:nth-child(3) {
    margin-top: 68px;
  }
}

/* ---------- 团队 ---------- */
.page-about .about-teams {
  display: grid;
  gap: 20px;
}

.page-about .about-team {
  border-top: 3px solid var(--chip);
  padding-top: 16px;
}

.page-about .about-team h3 {
  margin: 0 0 10px;
  font-family: var(--font-display);
  font-size: clamp(17px, 1.9vw, 20px);
  font-weight: 900;
  color: var(--table);
}

.page-about .about-team p {
  margin: 0;
  font-size: 14px;
  line-height: 1.82;
  color: var(--graphite);
}

@media (min-width: 780px) {
  .page-about .about-teams {
    grid-template-columns: repeat(3, minmax(0, 1fr));
    gap: 28px;
  }
}

/* ---------- 更新节拍 ---------- */
.page-about .about-points {
  list-style: none;
  margin: 0;
  padding: 0;
  display: grid;
  gap: 14px;
}

.page-about .about-points li {
  position: relative;
  padding-left: 26px;
  font-size: 15px;
  line-height: 1.82;
  color: var(--graphite);
}

.page-about .about-points li::before {
  content: "";
  position: absolute;
  left: 0;
  top: 9px;
  width: 10px;
  height: 10px;
  border-radius: 50%;
  background: var(--chip);
}

/* ---------- 用户数据 ---------- */
.page-about .about-stats {
  display: grid;
  gap: 16px;
}

.page-about .about-stat {
  padding: 18px 20px;
  background: var(--sand);
  border-left: 3px solid var(--chip);
  border-radius: 0 var(--about-radius-a) var(--about-radius-a) 0;
}

.page-about .about-stat__num {
  display: flex;
  align-items: baseline;
  gap: 3px;
  margin: 0 0 6px;
  font-family: var(--font-mono);
  font-variant-numeric: tabular-nums;
  font-size: clamp(30px, 4.4vw, 42px);
  font-weight: 700;
  line-height: 1;
  letter-spacing: -0.03em;
  color: var(--table);
}

.page-about .about-stat__num span {
  font-size: 0.42em;
  font-weight: 700;
  color: var(--chip);
}

.page-about .about-stat__label {
  margin: 0;
  font-size: 13px;
  line-height: 1.6;
  color: var(--fog);
}

@media (min-width: 720px) {
  .page-about .about-stats {
    grid-template-columns: repeat(3, minmax(0, 1fr));
  }
}

/* ---------- 下一步 ---------- */
.page-about .about-next {
  display: grid;
  gap: 24px;
}

.page-about .about-next__item {
  border-top: 3px solid var(--chip);
  padding-top: 18px;
}

.page-about .about-next__num {
  margin: 0 0 10px;
  font-family: var(--font-mono);
  font-size: 12px;
  letter-spacing: 0.18em;
  color: var(--gold);
}

.page-about .about-next__item h3 {
  margin: 0 0 10px;
  font-family: var(--font-display);
  font-size: clamp(17px, 1.9vw, 20px);
  font-weight: 900;
  color: var(--paper);
}

.page-about .about-next__item p {
  margin: 0;
  font-size: 14px;
  line-height: 1.82;
  color: rgba(247, 245, 239, 0.78);
}

@media (min-width: 860px) {
  .page-about .about-next {
    grid-template-columns: repeat(3, minmax(0, 1fr));
    gap: 30px;
  }
}

/* ---------- 收尾 ---------- */
.page-about .about-cta {
  padding-block: clamp(48px, 7vw, 82px);
  background: var(--paper);
  border-top: 4px solid var(--chip);
}

.page-about .about-cta__inner {
  display: grid;
  gap: 24px;
}

.page-about .about-cta__title {
  margin: 0 0 12px;
  font-family: var(--font-display);
  font-size: clamp(22px, 3vw, 32px);
  font-weight: 900;
  line-height: 1.25;
  letter-spacing: -0.02em;
  color: var(--table);
}

.page-about .about-cta__actions {
  display: flex;
  flex-wrap: wrap;
  gap: 12px;
}

@media (min-width: 820px) {
  .page-about .about-cta__inner {
    grid-template-columns: minmax(0, 1fr) auto;
    align-items: center;
    gap: 44px;
  }
}

/* ---------- 动效收敛 ---------- */
@media (prefers-reduced-motion: reduce) {
  .page-about *,
  .page-about *::before,
  .page-about *::after {
    transition-duration: 0.01ms !important;
  }

  .page-about .about-timeline__node:hover,
  .page-about .about-timeline__node:focus-visible,
  .page-about .about-principle:hover {
    transform: none;
  }
}