/* ===== 品牌概况 / profile ===== */
.page-about {
  background: var(--sand);
  color: var(--ink);
}

.page-about .crumb {
  padding-top: clamp(16px, 3vw, 26px);
}

/* ---------- 首屏 ---------- */
.page-about .about-hero {
  position: relative;
  padding: clamp(20px, 3vw, 34px) 0 clamp(34px, 5.5vw, 70px);
  isolation: isolate;
}

.page-about .about-hero::before {
  content: "";
  position: absolute;
  inset: 0;
  z-index: -1;
  background-image: repeating-linear-gradient(
    -6deg,
    rgba(38, 38, 42, 0.055) 0 2px,
    transparent 2px 11px
  );
  pointer-events: none;
}

.page-about .about-hero__grid {
  display: grid;
  grid-template-columns: minmax(0, 1fr);
  gap: clamp(26px, 4vw, 48px);
  align-items: end;
}

.page-about .about-hero__title {
  font-family: var(--font-display);
  font-weight: 900;
  font-size: clamp(2.05rem, 7.2vw, 4.3rem);
  line-height: 1.04;
  letter-spacing: -0.025em;
  margin: 14px 0 0;
  text-wrap: balance;
}

.page-about .about-hero__lede {
  margin: 20px 0 0;
  font-size: clamp(1rem, 1.7vw, 1.1rem);
  line-height: 1.85;
  max-width: 46ch;
}

.page-about .about-hero__actions {
  display: flex;
  flex-wrap: wrap;
  gap: 12px;
  margin-top: 26px;
}

.page-about .about-hero__side {
  border-top: var(--bd);
  padding-top: 18px;
}

.page-about .about-hero__aside-label {
  margin: 0 0 16px;
  font-family: var(--font-mono);
  font-size: 12.5px;
  letter-spacing: 0.14em;
  color: var(--ink-2);
}

.page-about .about-hero__stats {
  list-style: none;
  margin: 0;
  padding: 0;
  display: grid;
  grid-template-columns: repeat(2, minmax(0, 1fr));
  border: var(--bd);
  background: var(--paper);
  box-shadow: var(--shadow-hard);
}

.page-about .about-hero__stats .stat {
  padding: clamp(12px, 2.2vw, 17px);
  border-right: var(--bd);
  border-bottom: var(--bd);
}

.page-about .about-hero__stats .stat:nth-child(2n) {
  border-right: 0;
}

.page-about .about-hero__stats .stat:nth-child(n + 3) {
  border-bottom: 0;
}

.page-about .about-hero__stats .stat__num {
  display: block;
  font-family: var(--font-mono);
  font-weight: 700;
  font-size: clamp(1.3rem, 3.2vw, 1.7rem);
  line-height: 1.1;
  color: var(--sunset-ink);
  font-variant-numeric: tabular-nums;
}

.page-about .about-hero__stats .stat__label {
  display: block;
  margin-top: 6px;
  font-size: 12.5px;
  line-height: 1.5;
  color: var(--ink-2);
}

/* ---------- 主体网格 ---------- */
.page-about .about-body {
  padding-bottom: clamp(40px, 7vw, 80px);
}

.page-about .about-body__grid {
  display: grid;
  grid-template-columns: minmax(0, 1fr);
  gap: clamp(22px, 4vw, 40px);
}

/* 左侧篇目 */
.page-about .about-rail {
  border-top: var(--bd);
  border-bottom: var(--bd);
  padding: 12px 0;
}

.page-about .about-rail__title {
  margin: 0 0 10px;
  font-family: var(--font-mono);
  font-size: 12px;
  letter-spacing: 0.14em;
  color: var(--ink-2);
}

.page-about .about-rail__list {
  list-style: none;
  margin: 0;
  padding: 0;
  display: flex;
  gap: 10px;
  overflow-x: auto;
  -webkit-overflow-scrolling: touch;
  scrollbar-width: thin;
}

.page-about .about-rail__link {
  display: inline-flex;
  align-items: center;
  gap: 8px;
  padding: 7px 12px;
  border: var(--bd);
  background: var(--paper);
  color: var(--ink);
  text-decoration: none;
  font-size: 13.5px;
  line-height: 1.3;
  white-space: nowrap;
  transition: background 160ms ease, color 160ms ease;
}

.page-about .about-rail__link:hover,
.page-about .about-rail__link:focus-visible {
  background: var(--ink);
  color: var(--sand);
}

.page-about .about-rail__tick {
  flex: none;
  width: 8px;
  height: 8px;
  background: var(--turf);
}

.page-about .about-rail__no {
  display: none;
  font-family: var(--font-mono);
  font-size: 11px;
  letter-spacing: 0.12em;
  color: var(--ink-2);
}

.page-about .about-rail__foot {
  margin: 12px 0 0;
  font-size: 12.5px;
  color: var(--ink-2);
}

/* 右侧内容流 */
.page-about .about-flow {
  min-width: 0;
  display: grid;
  gap: clamp(34px, 6vw, 66px);
}

.page-about .chap {
  min-width: 0;
  padding-top: clamp(20px, 3vw, 30px);
  border-top: var(--bd);
  scroll-margin-top: 96px;
}

.page-about .chap__head {
  display: flex;
  align-items: baseline;
  gap: clamp(10px, 2vw, 18px);
  margin-bottom: clamp(16px, 2.6vw, 26px);
}

.page-about .chap__num {
  flex: none;
  font-family: var(--font-mono);
  font-weight: 700;
  font-size: clamp(1.9rem, 5vw, 3rem);
  line-height: 0.9;
  letter-spacing: -0.05em;
  color: var(--sunset);
  font-variant-numeric: tabular-nums;
}

.page-about .chap__title {
  margin: 0;
  font-family: var(--font-display);
  font-weight: 900;
  font-size: clamp(1.4rem, 3.6vw, 2.1rem);
  line-height: 1.18;
  letter-spacing: -0.015em;
}

.page-about .chap__figure {
  margin: 0 0 clamp(20px, 3vw, 30px);
}

.page-about .chap__figure img {
  display: block;
  width: 100%;
  max-width: 100%;
  height: auto;
  border: var(--bd);
  box-shadow: var(--shadow-hard);
  background: var(--sand-deep);
}

.page-about .chap__figure figcaption {
  margin-top: 10px;
  max-width: 54ch;
  font-size: 12.5px;
  line-height: 1.65;
  color: var(--ink-2);
}

.page-about .about-p {
  margin: 0 0 1.2em;
  font-size: 17px;
  line-height: 1.8;
  max-width: 40rem;
}

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

/* ---------- 四块内容 ---------- */
.page-about .about-pillars {
  list-style: none;
  margin: clamp(18px, 3vw, 26px) 0 0;
  padding: 0;
  display: grid;
  gap: clamp(14px, 2vw, 20px);
}

.page-about .about-pillar {
  display: grid;
  align-content: start;
  gap: 9px;
  padding: clamp(16px, 2.4vw, 24px);
  background: var(--paper);
  border: var(--bd);
  box-shadow: var(--shadow-soft);
  transition: transform 180ms ease, box-shadow 180ms ease;
}

.page-about .about-pillar:hover {
  transform: translateY(-3px);
  box-shadow: var(--shadow-mid);
}

.page-about .about-pillar__num {
  font-family: var(--font-mono);
  font-size: 12px;
  letter-spacing: 0.12em;
  color: var(--turf);
}

.page-about .about-pillar__title {
  margin: 0;
  font-size: 1.08rem;
  font-weight: 800;
  line-height: 1.35;
}

.page-about .about-pillar__text {
  margin: 0;
  font-size: 15.5px;
  line-height: 1.75;
  color: var(--ink-2);
}

.page-about .about-link {
  justify-self: start;
  margin-top: 4px;
  padding-bottom: 2px;
  font-size: 14px;
  font-weight: 700;
  color: var(--sunset-ink);
  text-decoration: none;
  border-bottom: 2px solid currentColor;
}

.page-about .about-link:hover {
  color: var(--ink);
}

/* ---------- 数据说明牌 ---------- */
.page-about .about-board {
  margin: clamp(20px, 3vw, 30px) 0;
  padding: clamp(20px, 3vw, 32px);
  background: var(--ink);
  color: var(--sand);
  border: var(--bd);
  box-shadow: var(--shadow-hard);
}

.page-about .about-board__kicker {
  margin: 0 0 8px;
  font-family: var(--font-mono);
  font-size: 12px;
  letter-spacing: 0.16em;
  color: var(--volt);
}

.page-about .about-board__title {
  margin: 0 0 20px;
  font-size: clamp(1.08rem, 2.4vw, 1.45rem);
  font-weight: 800;
  line-height: 1.35;
  color: var(--paper);
}

.page-about .about-board__grid {
  display: grid;
  grid-template-columns: repeat(2, minmax(0, 1fr));
  border-top: var(--bd-light);
  border-left: var(--bd-light);
}

.page-about .about-board__item {
  padding: clamp(12px, 2vw, 18px);
  border-right: var(--bd-light);
  border-bottom: var(--bd-light);
}

.page-about .about-board__num {
  display: block;
  font-family: var(--font-mono);
  font-weight: 700;
  font-size: clamp(1.3rem, 3.2vw, 1.85rem);
  line-height: 1.1;
  color: var(--volt);
  font-variant-numeric: tabular-nums;
}

.page-about .about-board__label {
  display: block;
  margin-top: 6px;
  font-size: 12.5px;
  line-height: 1.6;
  color: rgba(245, 238, 227, 0.76);
}

/* ---------- 折叠问答 ---------- */
.page-about .about-panels {
  margin-top: clamp(18px, 3vw, 26px);
  border: var(--bd);
  background: var(--paper);
  box-shadow: var(--shadow-soft);
}

.page-about .about-panels__heading {
  margin: 0;
  font-size: inherit;
  font-weight: inherit;
}

.page-about .panel + .panel {
  border-top: 2px solid var(--hairline);
}

.page-about .panel__trigger {
  width: 100%;
  display: flex;
  align-items: center;
  gap: 14px;
  padding: 15px 18px;
  background: transparent;
  border: 0;
  color: var(--ink);
  font: inherit;
  font-weight: 700;
  font-size: 15.5px;
  line-height: 1.5;
  text-align: left;
  cursor: pointer;
  transition: background 160ms ease;
}

.page-about .panel__trigger:hover {
  background: var(--sand-deep);
}

.page-about .panel__mark {
  position: relative;
  flex: none;
  width: 14px;
  height: 14px;
  background: var(--turf);
}

.page-about .panel__mark::before,
.page-about .panel__mark::after {
  content: "";
  position: absolute;
  background: var(--paper);
}

.page-about .panel__mark::before {
  left: 2px;
  right: 2px;
  top: 6px;
  height: 2px;
}

.page-about .panel__mark::after {
  top: 2px;
  bottom: 2px;
  left: 6px;
  width: 2px;
}

.page-about .panel__trigger[aria-expanded="true"] .panel__mark::after {
  display: none;
}

.page-about .panel__body {
  padding: 0 18px 18px 46px;
}

.page-about .panel__body p {
  margin: 0;
  max-width: 46rem;
  font-size: 15.5px;
  line-height: 1.78;
  color: var(--ink-2);
}

/* ---------- 合作 ---------- */
.page-about .about-partners {
  list-style: none;
  margin: clamp(16px, 2.6vw, 24px) 0 0;
  padding: 0;
  display: grid;
  gap: 12px;
}

.page-about .about-partners li {
  position: relative;
  padding-left: 24px;
  font-size: 15.5px;
  line-height: 1.78;
  color: var(--ink-2);
  max-width: 44rem;
}

.page-about .about-partners li::before {
  content: "";
  position: absolute;
  left: 0;
  top: 0.72em;
  width: 13px;
  height: 3px;
  background: var(--sunset);
}

/* ---------- 接下来一年 ---------- */
.page-about .about-next {
  list-style: none;
  margin: 0;
  padding: 0;
  display: grid;
  gap: clamp(12px, 2vw, 16px);
}

.page-about .about-next li {
  padding: 15px 18px;
  background: var(--paper);
  border: var(--bd);
  border-left: 8px solid var(--turf);
  font-size: 15.5px;
  line-height: 1.78;
  color: var(--ink-2);
  max-width: 46rem;
}

.page-about .about-next__mark {
  display: block;
  margin-bottom: 4px;
  font-family: var(--font-mono);
  font-size: 12px;
  letter-spacing: 0.14em;
  color: var(--sunset-ink);
}

/* ---------- 页尾斜切色带 ---------- */
.page-about .about-coda {
  margin-top: clamp(40px, 6vw, 72px);
  padding: clamp(52px, 9vw, 104px) 0 clamp(44px, 7vw, 78px);
  background: var(--ink);
  color: var(--sand);
  clip-path: polygon(0 3.5%, 100% 0, 100% 100%, 0 100%);
}

.page-about .about-coda__inner {
  max-width: 48rem;
}

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

.page-about .about-coda__title {
  margin: 0;
  font-family: var(--font-display);
  font-weight: 900;
  font-size: clamp(1.5rem, 4.2vw, 2.5rem);
  line-height: 1.15;
  letter-spacing: -0.02em;
  color: var(--paper);
}

.page-about .about-coda__lede {
  margin: 16px 0 0;
  max-width: 40rem;
  font-size: 16px;
  line-height: 1.8;
  color: rgba(245, 238, 227, 0.82);
}

.page-about .about-coda__actions {
  display: flex;
  flex-wrap: wrap;
  gap: 12px;
  margin-top: 26px;
}

/* ---------- 焦点反馈 ---------- */
.page-about a:focus-visible,
.page-about button:focus-visible {
  outline: 3px solid var(--volt);
  outline-offset: 2px;
}

/* ---------- 桌面布局 ---------- */
@media (min-width: 760px) {
  .page-about .about-pillars {
    grid-template-columns: repeat(2, minmax(0, 1fr));
    padding-bottom: 18px;
  }

  .page-about .about-pillar:nth-child(even) {
    transform: translateY(18px);
  }

  .page-about .about-pillar:nth-child(even):hover {
    transform: translateY(15px);
  }

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

@media (min-width: 900px) {
  .page-about .about-hero__grid {
    grid-template-columns: minmax(0, 7.2fr) minmax(0, 4.8fr);
  }

  .page-about .about-body__grid {
    grid-template-columns: 196px minmax(0, 1fr);
    gap: clamp(28px, 4vw, 56px);
    align-items: start;
  }

  .page-about .about-rail {
    position: sticky;
    top: 104px;
    padding: 20px 0 0;
    border-top: var(--bd);
    border-bottom: 0;
  }

  .page-about .about-rail__list {
    display: block;
    overflow: visible;
    position: relative;
  }

  .page-about .about-rail__list::before {
    content: "";
    position: absolute;
    left: 5px;
    top: 16px;
    bottom: 16px;
    width: 2px;
    background: var(--hairline);
  }

  .page-about .about-rail__link {
    display: grid;
    grid-template-columns: 12px minmax(0, 1fr);
    grid-template-rows: auto auto;
    align-items: center;
    gap: 3px 12px;
    padding: 9px 0;
    border: 0;
    background: transparent;
    white-space: normal;
    transition: color 160ms ease;
  }

  .page-about .about-rail__link:hover,
  .page-about .about-rail__link:focus-visible {
    background: transparent;
    color: var(--sunset-ink);
  }

  .page-about .about-rail__tick {
    grid-column: 1;
    grid-row: 1 / span 2;
    width: 10px;
    height: 10px;
    border-radius: 50%;
    background: var(--paper);
    border: 2px solid var(--turf);
    position: relative;
    z-index: 1;
    justify-self: center;
  }

  .page-about .about-rail__text {
    grid-column: 2;
    grid-row: 1;
    font-weight: 700;
    font-size: 13.5px;
    color: inherit;
  }

  .page-about .about-rail__no {
    display: block;
    grid-column: 2;
    grid-row: 2;
    color: var(--ink-2);
  }
}

/* ---------- 降低动态偏好 ---------- */
@media (prefers-reduced-motion: reduce) {
  .page-about .about-pillar,
  .page-about .about-rail__link,
  .page-about .panel__trigger {
    transition: none;
  }

  .page-about .about-pillar:hover,
  .page-about .about-pillar:nth-child(even),
  .page-about .about-pillar:nth-child(even):hover {
    transform: none;
  }
}