.page-about {
  --ab-line: rgba(201, 168, 106, .26);
  --ab-line-strong: rgba(201, 168, 106, .55);
  --ab-panel: rgba(22, 53, 127, .40);
  --ab-panel-soft: rgba(22, 53, 127, .20);
  --ab-indent: clamp(52px, 6vw, 88px);
  background: var(--royal-deep);
  color: var(--warm-white);
  font-family: var(--font-sans);
}

.page-about .about-crumb {
  padding-top: 18px;
}

.page-about .royal-breadcrumb {
  font-size: 13px;
  letter-spacing: .04em;
  color: var(--muted);
}

.page-about .royal-breadcrumb a {
  color: var(--champagne-light);
}

.page-about section[id] {
  scroll-margin-top: 86px;
}

/* ---------- 首屏 ---------- */

.page-about .about-hero {
  padding: clamp(20px, 3.2vw, 40px) 0 clamp(30px, 4.4vw, 56px);
}

.page-about .about-hero__inner {
  display: grid;
  grid-template-columns: minmax(0, 1fr);
  gap: clamp(22px, 3.6vw, 40px);
  align-items: start;
}

.page-about .about-hero__frame {
  position: relative;
  padding: clamp(22px, 3.4vw, 46px);
  border: 2px solid var(--champagne);
  box-shadow: var(--shadow-hard);
  background:
    linear-gradient(150deg, rgba(42, 85, 200, .40), rgba(11, 30, 75, 0) 62%),
    var(--royal-core);
}

.page-about .about-hero__frame::before {
  content: "";
  position: absolute;
  left: -2px;
  top: -2px;
  width: 54px;
  height: 6px;
  background: var(--amber);
}

.page-about .about-hero__title {
  margin: 16px 0 0;
  font-family: var(--font-serif);
  font-weight: 900;
  font-size: clamp(1.9rem, 4.6vw, 3.25rem);
  line-height: 1.16;
  letter-spacing: -.01em;
  color: var(--warm-white);
}

.page-about .about-hero__lead {
  margin: 16px 0 0;
  max-width: 48ch;
  font-size: clamp(15px, 1.6vw, 17px);
  line-height: 1.85;
  color: var(--muted);
}

.page-about .about-hero__facts {
  display: grid;
  grid-template-columns: repeat(2, minmax(0, 1fr));
  gap: 16px 18px;
  margin: 26px 0 0;
  padding-top: 22px;
  border-top: 1px solid var(--ab-line-strong);
}

.page-about .about-hero__fact dt {
  font-size: 12px;
  letter-spacing: .1em;
  color: var(--champagne-light);
}

.page-about .about-hero__fact dd {
  margin: 6px 0 0;
  font-family: var(--font-num);
  font-variant-numeric: tabular-nums;
  font-size: clamp(1.35rem, 2.4vw, 1.85rem);
  font-weight: 800;
  line-height: 1.1;
  color: var(--champagne);
}

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

.page-about .about-figure__box {
  overflow: hidden;
  border: 2px solid var(--champagne);
  box-shadow: var(--shadow-hard);
  background: var(--royal-core);
}

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

.page-about .about-figure figcaption {
  margin-top: 12px;
  font-size: 12.5px;
  line-height: 1.7;
  letter-spacing: .02em;
  color: var(--muted);
}

.page-about .about-figure--cover {
  max-width: 460px;
}

/* ---------- 章节刻度条 ---------- */

.page-about .about-rail {
  position: sticky;
  top: 0;
  z-index: 8;
  background: rgba(11, 30, 75, .96);
  border-top: 1px solid var(--ab-line);
  border-bottom: 1px solid var(--ab-line);
}

.page-about .about-rail__list {
  display: flex;
  gap: 4px;
  overflow-x: auto;
  padding-top: 8px;
  padding-bottom: 8px;
  scrollbar-width: none;
}

.page-about .about-rail__list::-webkit-scrollbar {
  display: none;
}

.page-about .about-rail__link {
  display: inline-flex;
  align-items: center;
  gap: 7px;
  flex: none;
  padding: 6px 11px 8px;
  border-bottom: 2px solid transparent;
  color: var(--muted);
  font-size: 13px;
  letter-spacing: .05em;
  text-decoration: none;
  white-space: nowrap;
  transition: color .18s ease, border-color .18s ease;
}

.page-about .about-rail__link:hover {
  color: var(--champagne-light);
}

.page-about .about-rail__link.is-active {
  color: var(--amber);
  border-bottom-color: var(--amber);
}

.page-about .about-rail__no {
  font-family: var(--font-num);
  font-variant-numeric: tabular-nums;
  font-size: 11px;
  font-weight: 800;
  opacity: .85;
}

/* ---------- 章节骨架 ---------- */

.page-about .about-chapter {
  padding: clamp(34px, 5.4vw, 64px) 0;
  border-bottom: 1px solid var(--ab-line);
}

.page-about .about-chapter__inner {
  position: relative;
  padding-left: var(--ab-indent);
}

.page-about .about-chapter__head {
  display: block;
  margin-bottom: clamp(18px, 2.6vw, 30px);
}

.page-about .about-chapter__num {
  position: absolute;
  left: 0;
  top: -.34em;
  font-family: var(--font-serif);
  font-weight: 900;
  font-size: clamp(3rem, 6.6vw, 5.2rem);
  line-height: 1;
  letter-spacing: -.05em;
  color: rgba(201, 168, 106, .16);
  pointer-events: none;
  user-select: none;
}

.page-about .about-chapter h2 {
  margin: 0;
  font-family: var(--font-serif);
  font-weight: 800;
  font-size: clamp(1.45rem, 2.9vw, 2.1rem);
  line-height: 1.3;
  letter-spacing: -.005em;
  color: var(--warm-white);
}

.page-about .about-chapter__note {
  margin: 10px 0 0;
  font-family: var(--font-num);
  font-size: 12.5px;
  letter-spacing: .07em;
  color: var(--champagne);
}

.page-about .about-chapter__lead {
  margin: 0 0 clamp(18px, 2.4vw, 28px);
  max-width: 60ch;
  font-size: 16px;
  line-height: 1.85;
  color: var(--muted);
}

/* ---------- 时间线 ---------- */

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

.page-about .about-timeline__item {
  position: relative;
  padding: 0 0 26px 28px;
  border-left: 2px solid var(--ab-line);
}

.page-about .about-timeline__item:last-child {
  padding-bottom: 0;
  border-left-color: transparent;
}

.page-about .about-timeline__dot {
  position: absolute;
  left: -9px;
  top: 3px;
  width: 16px;
  height: 16px;
  border-radius: 50%;
  background: var(--champagne);
  box-shadow: 0 0 0 4px var(--royal-deep);
  transition: background .2s ease, transform .2s ease;
}

.page-about .about-timeline__item:hover .about-timeline__dot {
  background: var(--amber);
  transform: scale(1.18);
}

.page-about .about-timeline__ver {
  margin: 0 0 5px;
  font-family: var(--font-num);
  font-variant-numeric: tabular-nums;
  font-size: 12px;
  font-weight: 800;
  letter-spacing: .09em;
  color: var(--champagne);
}

.page-about .about-timeline__title {
  margin: 0 0 6px;
  font-family: var(--font-serif);
  font-size: 1.06rem;
  font-weight: 700;
  color: var(--warm-white);
}

.page-about .about-timeline__text {
  margin: 0;
  max-width: 58ch;
  font-size: 14.5px;
  line-height: 1.78;
  color: var(--muted);
}

/* ---------- 三类服务 ---------- */

.page-about .about-grid {
  display: grid;
  grid-template-columns: minmax(0, 1fr);
  gap: 16px;
}

.page-about .about-svc {
  position: relative;
  padding: 20px 18px 22px;
  border: 1px solid var(--ab-line);
  border-top: 3px solid var(--champagne);
  background: var(--ab-panel);
  transition: border-color .2s ease, transform .2s ease;
}

.page-about .about-svc:hover {
  border-color: var(--amber);
  border-top-color: var(--amber);
  transform: translateY(-4px);
}

.page-about .about-svc__no {
  display: block;
  font-family: var(--font-num);
  font-variant-numeric: tabular-nums;
  font-size: 26px;
  font-weight: 800;
  line-height: 1;
  color: rgba(201, 168, 106, .40);
}

.page-about .about-svc h3 {
  margin: 12px 0 8px;
  font-family: var(--font-serif);
  font-size: 1.16rem;
  font-weight: 700;
  color: var(--warm-white);
}

.page-about .about-svc p {
  margin: 0 0 12px;
  font-size: 14.5px;
  line-height: 1.76;
  color: var(--muted);
}

.page-about .about-svc__scene {
  margin: 0;
  padding-top: 12px;
  border-top: 1px dashed var(--ab-line-strong);
  font-size: 13px;
  line-height: 1.7;
  color: var(--champagne-light);
}

/* ---------- 版本卡片 ---------- */

.page-about .about-versions {
  display: grid;
  grid-template-columns: minmax(0, 1fr);
  gap: 12px;
}

.page-about .about-ver {
  border: 1px solid var(--ab-line);
  background: var(--ab-panel-soft);
}

.page-about .about-ver[open] {
  border-color: var(--ab-line-strong);
  background: var(--ab-panel);
}

.page-about .about-ver__sum {
  display: flex;
  align-items: center;
  gap: 12px;
  padding: 15px 16px;
  cursor: pointer;
  list-style: none;
  color: var(--warm-white);
  transition: color .18s ease;
}

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

.page-about .about-ver__sum:hover {
  color: var(--champagne-light);
}

.page-about .about-ver__tag {
  flex: none;
  font-family: var(--font-num);
  font-variant-numeric: tabular-nums;
  font-size: 11.5px;
  font-weight: 800;
  letter-spacing: .08em;
  color: var(--champagne);
}

.page-about .about-ver__name {
  flex: 1 1 auto;
  font-family: var(--font-serif);
  font-size: 1.02rem;
  font-weight: 700;
}

.page-about .about-ver__sign {
  position: relative;
  flex: none;
  width: 14px;
  height: 14px;
}

.page-about .about-ver__sign::before,
.page-about .about-ver__sign::after {
  content: "";
  position: absolute;
  background: var(--champagne);
  transition: transform .2s ease;
}

.page-about .about-ver__sign::before {
  left: 0;
  top: 6px;
  width: 14px;
  height: 2px;
}

.page-about .about-ver__sign::after {
  left: 6px;
  top: 0;
  width: 2px;
  height: 14px;
}

.page-about .about-ver[open] .about-ver__sign::after {
  transform: scaleY(0);
}

.page-about .about-ver__body {
  padding: 14px 16px 18px;
  border-top: 1px solid var(--ab-line);
  font-size: 14.5px;
  line-height: 1.78;
  color: var(--muted);
}

.page-about .about-ver__body p {
  margin: 0;
}

.page-about .about-figure--wide {
  margin-top: clamp(20px, 3vw, 32px);
}

/* ---------- 团队与维护 ---------- */

.page-about .about-team {
  display: grid;
  grid-template-columns: minmax(0, 1fr);
  gap: clamp(20px, 3vw, 34px);
  align-items: start;
}

.page-about .about-figure--square {
  max-width: 420px;
}

.page-about .about-role {
  position: relative;
  margin-bottom: 14px;
  padding: 2px 0 16px 18px;
  border-left: 2px solid var(--ab-line);
  transition: border-color .2s ease;
}

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

.page-about .about-role:hover {
  border-left-color: var(--amber);
}

.page-about .about-role__mark {
  position: absolute;
  left: -5px;
  top: 7px;
  width: 8px;
  height: 8px;
  background: var(--champagne);
  transform: rotate(45deg);
}

.page-about .about-role h3 {
  margin: 0 0 6px;
  font-family: var(--font-serif);
  font-size: 1.06rem;
  font-weight: 700;
  color: var(--warm-white);
}

.page-about .about-role p {
  margin: 0;
  font-size: 14.5px;
  line-height: 1.78;
  color: var(--muted);
}

.page-about .about-pace {
  display: grid;
  grid-template-columns: repeat(2, minmax(0, 1fr));
  gap: 16px;
  margin-top: clamp(20px, 3vw, 30px);
  padding-top: 20px;
  border-top: 1px solid var(--ab-line);
}

.page-about .about-pace__num {
  display: block;
  font-family: var(--font-num);
  font-variant-numeric: tabular-nums;
  font-size: clamp(1.3rem, 2.4vw, 1.7rem);
  font-weight: 800;
  line-height: 1.1;
  color: var(--champagne);
}

.page-about .about-pace__label {
  display: block;
  margin-top: 6px;
  font-size: 12.5px;
  line-height: 1.65;
  color: var(--muted);
}

/* ---------- 覆盖与年度回顾（浅色分区） ---------- */

.page-about .about-chapter--light {
  border-bottom: 0;
  background: var(--warm-white);
  color: var(--ink);
}

.page-about .about-chapter--light .about-chapter h2,
.page-about .about-chapter--light h2 {
  color: var(--ink);
}

.page-about .about-chapter--light .about-chapter__num {
  color: rgba(11, 30, 75, .10);
}

.page-about .about-chapter--light .about-chapter__note {
  color: var(--gold-deep);
}

.page-about .about-chapter--light .about-chapter__lead {
  color: var(--muted-ink);
}

.page-about .about-annual {
  margin-top: 4px;
  padding-top: 20px;
  border-top: 1px solid rgba(11, 30, 75, .18);
}

.page-about .about-annual__title {
  margin: 0 0 8px;
  font-family: var(--font-serif);
  font-size: 1.2rem;
  font-weight: 700;
  color: var(--royal-deep);
}

.page-about .about-annual__text {
  margin: 0 0 14px;
  font-size: 14.5px;
  line-height: 1.78;
  color: var(--muted-ink);
}

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

.page-about .about-annual__list li {
  display: flex;
  flex-wrap: wrap;
  align-items: baseline;
  gap: 10px;
  padding: 11px 0;
  border-bottom: 1px solid rgba(11, 30, 75, .12);
  font-size: 14.5px;
  line-height: 1.7;
  color: var(--ink);
}

.page-about .about-annual__k {
  flex: none;
  min-width: 46px;
  font-family: var(--font-num);
  font-variant-numeric: tabular-nums;
  font-size: 12px;
  font-weight: 800;
  letter-spacing: .08em;
  color: var(--gold-deep);
}

/* ---------- 延伸入口 ---------- */

.page-about .about-next {
  padding: clamp(34px, 5vw, 60px) 0 clamp(40px, 6vw, 72px);
}

.page-about .about-next__title {
  margin: 0;
  font-family: var(--font-serif);
  font-weight: 800;
  font-size: clamp(1.35rem, 2.6vw, 1.85rem);
  color: var(--warm-white);
}

.page-about .about-next__grid {
  display: grid;
  grid-template-columns: minmax(0, 1fr);
  gap: 14px;
  margin-top: 20px;
}

.page-about .about-next__card {
  display: flex;
  flex-direction: column;
  gap: 8px;
  height: 100%;
  text-decoration: none;
  color: inherit;
}

.page-about .about-next__go {
  margin-top: auto;
  padding-top: 12px;
  font-family: var(--font-num);
  font-size: 12.5px;
  letter-spacing: .07em;
  color: var(--champagne);
  transition: color .18s ease;
}

.page-about .about-next__card:hover .about-next__go,
.page-about .about-next__card:focus-visible .about-next__go {
  color: var(--amber);
}

/* ---------- 显现 ---------- */

.royal-js .page-about [data-reveal] {
  opacity: 0;
  transform: translateY(8px);
  transition: opacity .24s ease, transform .24s ease;
  animation: about-reveal-fallback 0s linear 1.8s forwards;
}

.royal-js .page-about [data-reveal].is-visible {
  opacity: 1;
  transform: none;
  animation: none;
}

@keyframes about-reveal-fallback {
  to {
    opacity: 1;
    transform: none;
  }
}

/* ---------- 断点 ---------- */

@media (min-width: 700px) {
  .page-about .about-hero__facts {
    grid-template-columns: repeat(4, minmax(0, 1fr));
  }

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

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

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

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

@media (min-width: 860px) {
  .page-about .about-team {
    grid-template-columns: minmax(0, .82fr) minmax(0, 1.18fr);
  }

  .page-about .about-figure--square {
    max-width: none;
  }
}

@media (min-width: 960px) {
  .page-about .about-hero__inner {
    grid-template-columns: minmax(0, 1.45fr) minmax(0, .8fr);
  }

  .page-about .about-figure--cover {
    max-width: none;
  }
}

@media (min-width: 1040px) {
  .page-about .about-next__grid {
    grid-template-columns: repeat(4, minmax(0, 1fr));
  }
}

@media (max-width: 480px) {
  .page-about .about-chapter__inner {
    padding-left: clamp(40px, 11vw, 52px);
  }

  .page-about .about-chapter__num {
    font-size: 2.5rem;
  }

  .page-about .about-timeline__item {
    padding-left: 22px;
  }
}

@media (prefers-reduced-motion: reduce) {
  .royal-js .page-about [data-reveal] {
    opacity: 1;
    transform: none;
    animation: none;
    transition: none;
  }

  .page-about .about-svc,
  .page-about .about-timeline__dot,
  .page-about .about-role,
  .page-about .about-rail__link,
  .page-about .about-next__go {
    transition: none;
  }

  .page-about .about-svc:hover {
    transform: none;
  }

  .page-about .about-timeline__item:hover .about-timeline__dot {
    transform: none;
  }
}