.page-about {
  --about-gutter: clamp(16px, 4vw, 44px);
  --about-line: rgba(201, 162, 39, 0.28);
  overflow-x: hidden;
}

.page-about .about-crumbs {
  max-width: var(--shell);
  margin-inline: auto;
  padding: 22px var(--about-gutter) 0;
}

/* ---------- 首屏 ---------- */
.page-about .about-hero {
  padding-block: clamp(24px, 5vw, 56px) 0;
}

.page-about .about-hero__inner {
  position: relative;
  max-width: var(--shell);
  margin-inline: auto;
  padding-inline: var(--about-gutter);
  display: grid;
  grid-template-columns: minmax(0, 1fr);
  gap: 14px 36px;
}

.page-about .about-hero__seal {
  width: 104px;
  height: 104px;
  display: grid;
  place-items: center;
  align-content: center;
  gap: 4px;
  border: 1px solid var(--gilt);
  border-radius: 6px;
  background:
    radial-gradient(circle at 50% 40%, rgba(242, 169, 59, 0.16), transparent 68%),
    linear-gradient(160deg, rgba(30, 76, 92, 0.55), rgba(15, 21, 25, 0.9));
  box-shadow: inset 0 0 0 5px rgba(15, 21, 25, 0.55), 0 8px 24px rgba(0, 0, 0, 0.35);
  margin-bottom: 6px;
}

.page-about .about-hero__seal-year {
  font-family: var(--font-mono);
  font-size: 22px;
  letter-spacing: 0.08em;
  color: var(--amber);
}

.page-about .about-hero__seal-word {
  font-family: var(--font-serif);
  font-size: 13px;
  letter-spacing: 0.32em;
  color: var(--gilt);
  padding-left: 0.32em;
}

.page-about .about-kicker {
  margin: 0;
  font-family: var(--font-mono);
  font-size: 11px;
  letter-spacing: 0.22em;
  color: var(--lapis-lt);
  text-transform: uppercase;
}

.page-about .about-hero__title {
  margin: 0;
  font-family: var(--font-serif);
  font-weight: 600;
  font-size: clamp(29px, 5.6vw, 54px);
  line-height: 1.26;
  letter-spacing: 0.04em;
  color: var(--ivory);
}

.page-about .about-hero__lead {
  margin: 6px 0 0;
  max-width: 40em;
  font-size: clamp(15px, 1.8vw, 18px);
  line-height: 1.92;
  color: rgba(250, 245, 234, 0.8);
}

.page-about .about-hero__meta {
  display: flex;
  flex-wrap: wrap;
  gap: 12px 34px;
  margin: 18px 0 0;
  padding-top: 18px;
  border-top: 1px solid var(--about-line);
}

.page-about .about-hero__meta-item {
  display: flex;
  flex-direction: column;
  gap: 4px;
}

.page-about .about-hero__meta-item dt {
  font-family: var(--font-mono);
  font-size: 10px;
  letter-spacing: 0.18em;
  color: var(--muted);
}

.page-about .about-hero__meta-item dd {
  margin: 0;
  font-family: var(--font-serif);
  font-size: 19px;
  letter-spacing: 0.03em;
  color: var(--gilt);
}

.page-about .about-hero__figure {
  max-width: var(--shell);
  margin: clamp(30px, 5vw, 54px) auto 0;
  padding-inline: var(--about-gutter);
}

.page-about .about-hero__cap {
  margin-top: 12px;
  font-size: 12.5px;
  line-height: 1.7;
  color: var(--muted);
  letter-spacing: 0.02em;
}

/* ---------- 视觉容器 ---------- */
.page-about .about-media {
  position: relative;
  display: block;
  overflow: hidden;
  aspect-ratio: 16 / 10;
  border: 1px solid var(--about-line);
  background: linear-gradient(150deg, rgba(30, 76, 92, 0.45), rgba(15, 21, 25, 0.92));
}

.page-about .about-media--square {
  aspect-ratio: 10 / 7;
}

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

/* ---------- 章节 ---------- */
.page-about .about-chapter {
  max-width: var(--shell);
  margin-inline: auto;
  padding: clamp(42px, 6.5vw, 90px) var(--about-gutter);
}

.page-about .about-chapter__num {
  margin: 0 0 14px;
  font-family: var(--font-mono);
  font-size: 11px;
  letter-spacing: 0.24em;
  color: var(--amber);
}

.page-about .about-chapter h2 {
  margin: 0 0 1.1em;
  font-family: var(--font-serif);
  font-weight: 600;
  font-size: clamp(22px, 3.3vw, 33px);
  line-height: 1.4;
  letter-spacing: 0.035em;
  color: var(--ivory);
}

.page-about .about-chapter__body p {
  margin: 0 0 1.15em;
  font-size: clamp(15px, 1.7vw, 16.5px);
  line-height: 1.92;
  color: rgba(250, 245, 234, 0.8);
}

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

.page-about .about-foot {
  margin: 22px 0 0;
  font-size: 14px;
  line-height: 1.9;
  color: var(--muted);
}

.page-about .about-link {
  color: var(--amber);
  text-decoration: none;
  border-bottom: 1px solid rgba(242, 169, 59, 0.45);
  padding-bottom: 1px;
  transition: color var(--dur) var(--ease), border-color var(--dur) var(--ease);
}

.page-about .about-link:hover,
.page-about .about-link:focus-visible {
  color: var(--ivory);
  border-bottom-color: var(--gilt);
}

/* ---------- 色带 ---------- */
.page-about .about-band--paper {
  background: var(--paper);
  color: var(--ink);
  border-block: 1px solid var(--line);
}

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

.page-about .about-band--paper .about-chapter__num {
  color: var(--ochre);
}

.page-about .about-band--paper .about-chapter__body p,
.page-about .about-band--paper .about-foot {
  color: rgba(15, 21, 25, 0.76);
}

.page-about .about-band--lapis {
  background:
    radial-gradient(circle at 88% 12%, rgba(201, 162, 39, 0.14), transparent 52%),
    linear-gradient(175deg, var(--lapis), var(--ink-soft) 84%);
  border-block: 1px solid var(--about-line);
}

/* ---------- 说明牌 ---------- */
.page-about .about-plates {
  display: grid;
  grid-template-columns: minmax(0, 1fr);
  gap: 14px;
  margin-top: 22px;
}

.page-about .about-plate {
  position: relative;
  padding: 18px 18px 20px;
  border: 1px solid var(--about-line);
  background: rgba(250, 245, 234, 0.04);
}

.page-about .about-plate::before {
  content: "";
  position: absolute;
  inset: 0 0 auto 0;
  height: 3px;
  background: var(--ochre);
}

.page-about .about-plate--paper {
  background: var(--ivory);
  border-color: var(--line);
  transition: transform var(--dur) var(--ease), border-color var(--dur) var(--ease), box-shadow var(--dur) var(--ease);
}

.page-about .about-plate--paper:hover,
.page-about .about-plate--paper:focus-within {
  transform: translateY(-3px);
  border-color: var(--ochre);
  box-shadow: 0 10px 22px rgba(15, 21, 25, 0.12);
}

.page-about .about-plate__label {
  margin: 6px 0 8px;
  font-family: var(--font-mono);
  font-size: 11px;
  letter-spacing: 0.16em;
  color: var(--ochre);
}

.page-about .about-plate__body {
  margin: 0;
  font-size: 14px;
  line-height: 1.85;
  color: rgba(15, 21, 25, 0.78);
}

.page-about .about-plate--dark {
  margin-top: 26px;
  background: rgba(30, 76, 92, 0.16);
}

.page-about .about-plate--dark .about-plate__label {
  color: var(--amber);
}

.page-about .about-plate--dark .about-plate__body {
  color: rgba(250, 245, 234, 0.76);
}

/* ---------- 合作分工 ---------- */
.page-about .about-split {
  display: grid;
  grid-template-columns: minmax(0, 1fr);
  gap: 22px;
  margin: 26px 0 30px;
}

.page-about .about-split__item {
  border-top: 2px solid var(--ochre);
  padding-top: 14px;
}

.page-about .about-split__item h3 {
  margin: 0 0 10px;
  font-family: var(--font-serif);
  font-weight: 600;
  font-size: 18px;
  letter-spacing: 0.04em;
  color: var(--gilt);
}

.page-about .about-split__item p {
  margin: 0;
  font-size: 14.5px;
  line-height: 1.88;
  color: rgba(250, 245, 234, 0.76);
}

/* ---------- 图 ---------- */
.page-about .about-figure {
  margin: 30px 0 6px;
}

.page-about .about-figure__cap {
  margin-top: 10px;
  font-size: 12.5px;
  line-height: 1.7;
  color: var(--muted);
}

.page-about .about-band--paper .about-figure__cap {
  color: rgba(15, 21, 25, 0.55);
}

/* ---------- 长卷横轴 ---------- */
.page-about .about-scroll {
  margin: 26px 0 8px;
  padding: 18px 0 12px;
  overflow-x: auto;
  border-top: 1px solid var(--about-line);
  border-bottom: 1px solid var(--about-line);
  -webkit-overflow-scrolling: touch;
}

.page-about .about-scroll svg {
  display: block;
  width: 100%;
  min-width: 720px;
  height: auto;
}

.page-about .about-scroll:focus-visible {
  outline: 1px solid var(--gilt);
  outline-offset: 4px;
}

/* ---------- 时间轴 ---------- */
.page-about .about-timeline {
  list-style: none;
  margin: 30px 0 0;
  padding: 0 0 0 20px;
  border-left: 1px solid var(--about-line);
}

.page-about .about-timeline__item {
  position: relative;
  padding-bottom: 6px;
}

.page-about .about-timeline__item::before {
  content: "";
  position: absolute;
  left: -25px;
  top: 14px;
  width: 8px;
  height: 8px;
  border: 1px solid var(--gilt);
  background: var(--ink);
  transform: rotate(45deg);
}

.page-about .about-timeline__node {
  border-bottom: 1px solid rgba(217, 205, 184, 0.16);
}

.page-about .about-timeline__node > summary {
  display: flex;
  flex-wrap: wrap;
  align-items: baseline;
  gap: 6px 16px;
  padding: 12px 0;
  cursor: pointer;
  list-style: none;
}

.page-about .about-timeline__node > summary::-webkit-details-marker {
  display: none;
}

.page-about .about-timeline__when {
  font-family: var(--font-mono);
  font-size: 11px;
  letter-spacing: 0.16em;
  color: var(--amber);
  min-width: 6.5em;
}

.page-about .about-timeline__what {
  font-family: var(--font-serif);
  font-size: 16.5px;
  letter-spacing: 0.04em;
  color: var(--ivory);
  transition: color var(--dur) var(--ease);
}

.page-about .about-timeline__node > summary::after {
  content: "+";
  margin-left: auto;
  font-family: var(--font-mono);
  font-size: 14px;
  color: var(--lapis-lt);
}

.page-about .about-timeline__node[open] > summary::after {
  content: "−";
  color: var(--amber);
}

.page-about .about-timeline__node[open] > summary .about-timeline__what {
  color: var(--gilt);
}

.page-about .about-timeline__node p {
  margin: 0 0 14px;
  font-size: 14.5px;
  line-height: 1.88;
  color: rgba(250, 245, 234, 0.75);
  max-width: 46em;
}

/* ---------- 卷末 ---------- */
.page-about .about-next-section {
  padding: clamp(44px, 6.5vw, 88px) 0 clamp(52px, 7vw, 96px);
  background: linear-gradient(180deg, rgba(15, 21, 25, 0), rgba(30, 76, 92, 0.22));
  border-top: 1px solid var(--about-line);
}

.page-about .about-next-inner {
  max-width: var(--shell);
  margin-inline: auto;
  padding-inline: var(--about-gutter);
}

.page-about .about-next-inner h2 {
  margin: 0 0 26px;
  font-family: var(--font-serif);
  font-weight: 600;
  font-size: clamp(22px, 3.1vw, 30px);
  letter-spacing: 0.04em;
  color: var(--ivory);
}

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

.page-about .about-next__card {
  display: flex;
  flex-direction: column;
  gap: 7px;
  padding: 20px 18px;
  border: 1px solid var(--about-line);
  background: rgba(250, 245, 234, 0.03);
  text-decoration: none;
  transition: border-color var(--dur) var(--ease), background var(--dur) var(--ease), transform var(--dur) var(--ease);
}

.page-about .about-next__card:hover,
.page-about .about-next__card:focus-visible {
  border-color: var(--amber);
  background: rgba(242, 169, 59, 0.07);
  transform: translateY(-2px);
}

.page-about .about-next__kicker {
  font-family: var(--font-mono);
  font-size: 10.5px;
  letter-spacing: 0.18em;
  color: var(--lapis-lt);
}

.page-about .about-next__title {
  font-family: var(--font-serif);
  font-size: 18px;
  letter-spacing: 0.035em;
  color: var(--ivory);
}

.page-about .about-next__desc {
  font-size: 13.5px;
  line-height: 1.75;
  color: rgba(250, 245, 234, 0.66);
}

/* ---------- 响应式 ---------- */
@media (min-width: 620px) {
  .page-about .about-plates {
    grid-template-columns: repeat(2, minmax(0, 1fr));
  }
  .page-about .about-split {
    grid-template-columns: repeat(2, minmax(0, 1fr));
  }
  .page-about .about-next {
    grid-template-columns: repeat(2, minmax(0, 1fr));
  }
}

@media (min-width: 860px) {
  .page-about .about-hero__inner {
    grid-template-columns: minmax(0, 1fr) 150px;
    align-items: start;
    gap: 12px 40px;
  }
  .page-about .about-hero__seal {
    grid-column: 2;
    grid-row: 1 / span 3;
    justify-self: end;
    width: 126px;
    height: 126px;
    margin-bottom: 0;
  }
  .page-about .about-kicker,
  .page-about .about-hero__title,
  .page-about .about-hero__lead {
    grid-column: 1;
  }
  .page-about .about-hero__meta {
    grid-column: 1 / -1;
  }
  .page-about .about-hero__meta-item dd {
    font-size: 22px;
  }
  .page-about .about-plates {
    grid-template-columns: repeat(3, minmax(0, 1fr));
    gap: 18px;
  }
  .page-about .about-plates .about-plate:nth-child(2) {
    transform: translateY(14px);
  }
  .page-about .about-plates .about-plate:nth-child(2):hover {
    transform: translateY(11px);
  }
  .page-about .about-split {
    grid-template-columns: repeat(3, minmax(0, 1fr));
    gap: 30px;
  }
  .page-about .about-next {
    grid-template-columns: repeat(4, minmax(0, 1fr));
  }
  .page-about .about-next__card:nth-child(even) {
    transform: translateY(12px);
  }
  .page-about .about-next__card:nth-child(even):hover {
    transform: translateY(9px);
  }
  .page-about .about-figure {
    max-width: 84%;
  }
  .page-about .about-figure--wide {
    max-width: 92%;
    margin-left: auto;
  }
  .page-about .about-timeline {
    padding-left: 26px;
  }
  .page-about .about-timeline__item::before {
    left: -31px;
  }
}

@media (min-width: 1080px) {
  .page-about .about-hero__lead {
    font-size: 18.5px;
  }
  .page-about .about-chapter h2 {
    max-width: 22em;
  }
}

@media (prefers-reduced-motion: reduce) {
  .page-about .about-plate--paper,
  .page-about .about-next__card,
  .page-about .about-link,
  .page-about .about-timeline__what {
    transition: none;
  }
  .page-about .about-plate--paper:hover,
  .page-about .about-next__card:hover {
    transform: none;
  }
}