.page-about {
  --about-rail: 260px;
  --about-line: rgba(245, 242, 233, 0.14);
  --about-soft: rgba(245, 242, 233, 0.72);
}

/* ---------- 首屏 ---------- */
.page-about .about-hero {
  display: grid;
  gap: 1.75rem;
  padding-block: clamp(1.75rem, 5vw, 3.5rem) clamp(1.5rem, 4vw, 2.5rem);
  align-items: start;
}

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

.page-about .about-hero__main h1 {
  font-family: var(--font-display);
  font-weight: 900;
  font-size: clamp(2.15rem, 7.2vw, 4rem);
  line-height: 1.04;
  letter-spacing: -0.02em;
  margin: 0.65rem 0 1.1rem;
  color: var(--porcelain);
  text-wrap: balance;
}

.page-about .about-hero__main .lede {
  max-width: 46ch;
}

.page-about .about-brief {
  background: var(--porcelain);
  color: var(--charcoal);
  border: 3px solid var(--charcoal);
  border-radius: var(--radius);
  box-shadow: var(--shadow-hard);
  padding: 1.1rem 1.15rem 1.25rem;
}

.page-about .about-brief__label {
  margin: 0 0 0.75rem;
  font-size: 0.75rem;
  letter-spacing: 0.16em;
  text-transform: uppercase;
  color: rgba(20, 17, 14, 0.62);
}

.page-about .about-brief__list {
  list-style: none;
  margin: 0;
  padding: 0;
  display: grid;
  gap: 0.55rem;
  font-size: 0.9375rem;
  line-height: 1.6;
}

.page-about .about-brief__list li {
  display: flex;
  align-items: baseline;
  gap: 0.6rem;
  border-bottom: 1px solid rgba(20, 17, 14, 0.12);
  padding-bottom: 0.55rem;
}

.page-about .about-brief__list li:last-child {
  border-bottom: 0;
  padding-bottom: 0;
}

.page-about .about-brief__list .mono {
  font-weight: 700;
  font-size: 1.05rem;
  color: var(--neon);
  min-width: 3.2rem;
}

/* ---------- 主体 + 注解栏 ---------- */
.page-about .about-layout {
  display: grid;
  grid-template-columns: 1fr;
  gap: 2.25rem;
  padding-bottom: clamp(2.5rem, 6vw, 5rem);
}

.page-about .about-layout__body {
  min-width: 0;
  display: grid;
  gap: clamp(2.25rem, 5vw, 3.5rem);
}

/* ---------- 章节 ---------- */
.page-about .about-section {
  min-width: 0;
}

.page-about .about-section__head {
  display: grid;
  grid-template-columns: auto minmax(0, 1fr);
  align-items: start;
  gap: 0.35rem 0.9rem;
  margin-bottom: 1rem;
  border-top: 2px solid var(--about-line);
  padding-top: 1rem;
}

.page-about .about-num {
  font-family: var(--font-mono);
  font-weight: 800;
  font-size: clamp(1.75rem, 5vw, 2.75rem);
  line-height: 0.85;
  letter-spacing: -0.05em;
  color: var(--neon);
  text-shadow: 0 0 22px rgba(123, 77, 255, 0.45);
}

.page-about .about-section__head .h-section {
  margin: 0;
  align-self: center;
}

.page-about .about-section__lead {
  margin: 0 0 1.4rem;
  color: var(--about-soft);
  max-width: 56ch;
}

.page-about .about-section__body p {
  margin: 0 0 1rem;
  max-width: 62ch;
}

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

.page-about .about-section__body a {
  color: var(--gold-light);
  text-decoration: underline;
  text-underline-offset: 3px;
  text-decoration-thickness: 1px;
}

.page-about .about-section__body a:hover,
.page-about .about-section__body a:focus-visible {
  color: var(--gold);
}

/* ---------- 四类房间 ---------- */
.page-about .room-grid {
  display: grid;
  grid-template-columns: 1fr;
  gap: 1.1rem;
}

.page-about .room-block {
  position: relative;
  min-width: 0;
  background: linear-gradient(158deg, rgba(123, 77, 255, 0.16) 0%, rgba(7, 35, 26, 0.94) 62%);
  border: 2px solid rgba(185, 164, 255, 0.34);
  border-radius: var(--radius);
  box-shadow: var(--shadow-hard);
  padding: 1.15rem 1.15rem 1.25rem;
  transition: transform 0.24s var(--ease), box-shadow 0.24s var(--ease), border-color 0.24s var(--ease);
}

.page-about .room-block:hover,
.page-about .room-block:focus-within {
  transform: translateY(-5px);
  border-color: var(--neon);
  box-shadow: var(--shadow-hard-lg);
}

.page-about .room-block:focus-visible {
  outline: 3px solid var(--gold);
  outline-offset: 3px;
}

.page-about .room-block__icon {
  display: block;
  color: var(--gold);
  margin-bottom: 0.7rem;
}

.page-about .room-block__title {
  margin: 0 0 0.25rem;
  color: var(--porcelain);
}

.page-about .room-block__meta {
  margin: 0 0 0.7rem;
  font-size: 0.78rem;
  letter-spacing: 0.08em;
  color: var(--gold-light);
}

.page-about .room-block__body {
  margin: 0 0 0.7rem;
  font-size: 0.9375rem;
  line-height: 1.72;
  color: var(--about-soft);
}

.page-about .room-block__detail {
  margin: 0;
  padding-top: 0.65rem;
  border-top: 1px dashed rgba(245, 242, 233, 0.2);
  font-size: 0.8125rem;
  line-height: 1.6;
  color: rgba(245, 242, 233, 0.55);
  transition: color 0.24s var(--ease);
}

.page-about .room-block:hover .room-block__detail,
.page-about .room-block:focus-within .room-block__detail {
  color: var(--neon-soft);
}

/* ---------- 时间线 ---------- */
.page-about .about-timeline {
  margin-block: 1.25rem 1.75rem;
}

.page-about .about-timeline__track {
  display: grid;
  grid-auto-flow: column;
  grid-auto-columns: minmax(212px, 1fr);
  gap: 1.25rem;
  list-style: none;
  margin: 0;
  padding: 1.6rem 0.25rem 1.35rem;
  overflow-x: auto;
  overscroll-behavior-x: contain;
  scroll-snap-type: x proximity;
  -webkit-overflow-scrolling: touch;
}

.page-about .about-timeline__track::-webkit-scrollbar {
  height: 6px;
}

.page-about .about-timeline__track::-webkit-scrollbar-thumb {
  background: rgba(123, 77, 255, 0.55);
  border-radius: 999px;
}

.page-about .about-timeline__node {
  position: relative;
  min-width: 0;
  padding: 0.85rem 0.35rem 0.35rem;
  scroll-snap-align: start;
  transition: transform 0.24s var(--ease);
}

.page-about .about-timeline__node::before {
  content: "";
  position: absolute;
  top: 0;
  left: 0;
  width: 100%;
  height: 2px;
  border-radius: 2px;
  background: linear-gradient(90deg, var(--gold) 0%, var(--neon) 88%, rgba(123, 77, 255, 0) 100%);
}

.page-about .about-timeline__node:last-child::before {
  background: linear-gradient(90deg, var(--gold) 0%, var(--neon) 55%, rgba(123, 77, 255, 0) 100%);
}

.page-about .about-timeline__dot {
  position: absolute;
  top: -5px;
  left: 0;
  width: 12px;
  height: 12px;
  border-radius: 50%;
  background: var(--gold);
  box-shadow: 0 0 0 4px rgba(231, 183, 95, 0.16);
  transition: box-shadow 0.24s var(--ease);
}

.page-about .about-timeline__node:hover,
.page-about .about-timeline__node:focus-within {
  transform: translateY(-5px);
}

.page-about .about-timeline__node:hover .about-timeline__dot,
.page-about .about-timeline__node:focus-within .about-timeline__dot {
  box-shadow: 0 0 0 7px rgba(231, 183, 95, 0.24);
}

.page-about .about-timeline__node:focus-visible {
  outline: 3px solid var(--gold);
  outline-offset: 4px;
  border-radius: 4px;
}

.page-about .about-timeline__stage {
  margin: 0 0 0.4rem;
  font-size: 0.72rem;
  letter-spacing: 0.16em;
  color: var(--gold);
}

.page-about .about-timeline__title {
  margin: 0 0 0.5rem;
  font-family: var(--font-display);
  font-weight: 800;
  font-size: 1.1rem;
  line-height: 1.3;
  color: var(--porcelain);
}

.page-about .about-timeline__text {
  margin: 0 0 0.6rem;
  font-size: 0.875rem;
  line-height: 1.72;
  color: var(--about-soft);
}

.page-about .about-timeline__more {
  margin: 0;
  padding-left: 0.7rem;
  border-left: 2px solid rgba(123, 77, 255, 0.42);
  font-size: 0.78rem;
  line-height: 1.62;
  color: rgba(245, 242, 233, 0.5);
  transition: color 0.24s var(--ease), border-color 0.24s var(--ease);
}

.page-about .about-timeline__node:hover .about-timeline__more,
.page-about .about-timeline__node:focus-within .about-timeline__more {
  color: var(--neon-soft);
  border-color: var(--neon);
}

/* ---------- 配图 ---------- */
.page-about .about-figure {
  margin: clamp(1.5rem, 4vw, 2.25rem) 0 0;
}

.page-about .about-figure .figure__media {
  overflow: hidden;
  border-radius: var(--radius);
  border: 2px solid rgba(245, 242, 233, 0.16);
  box-shadow: var(--shadow-hard);
}

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

.page-about .about-figure--rooms .figure__media {
  aspect-ratio: 9 / 7;
}

.page-about .about-figure--versions .figure__media {
  aspect-ratio: 5 / 3;
}

.page-about .about-figure--legacy .figure__media {
  aspect-ratio: 4 / 3;
}

.page-about .about-figure .figure__caption {
  margin-top: 0.7rem;
  font-size: 0.8125rem;
  line-height: 1.6;
  color: rgba(245, 242, 233, 0.55);
}

/* ---------- 右侧注解栏 ---------- */
.page-about .about-notes {
  min-width: 0;
  order: -1;
}

.page-about .about-notes__inner {
  background: var(--porcelain);
  color: var(--charcoal);
  border: 3px solid var(--charcoal);
  border-radius: var(--radius);
  box-shadow: var(--shadow-hard);
  padding: 1.1rem 1.15rem 1.25rem;
}

.page-about .about-notes__label {
  margin: 0 0 0.85rem;
  padding-bottom: 0.6rem;
  border-bottom: 2px solid rgba(20, 17, 14, 0.85);
  font-size: 0.72rem;
  letter-spacing: 0.18em;
  text-transform: uppercase;
  color: rgba(20, 17, 14, 0.6);
}

.page-about .about-notes__list {
  margin: 0;
  display: grid;
  gap: 0.5rem;
}

.page-about .about-notes__row {
  display: flex;
  align-items: baseline;
  justify-content: space-between;
  gap: 0.75rem;
  padding-bottom: 0.45rem;
  border-bottom: 1px dashed rgba(20, 17, 14, 0.18);
}

.page-about .about-notes__row:last-child {
  border-bottom: 0;
  padding-bottom: 0;
}

.page-about .about-notes__term {
  font-size: 0.8125rem;
  line-height: 1.5;
  color: rgba(20, 17, 14, 0.74);
}

.page-about .about-notes__value {
  margin: 0;
  font-family: var(--font-mono);
  font-weight: 700;
  font-size: 1.0625rem;
  letter-spacing: -0.02em;
  color: var(--felt-deep);
  white-space: nowrap;
}

.page-about .about-notes__value span {
  font-size: 0.72rem;
  color: var(--neon);
  margin-left: 0.1rem;
}

/* ---------- 响应式 ---------- */
@media (min-width: 640px) {
  .page-about .room-grid {
    grid-template-columns: repeat(2, minmax(0, 1fr));
  }
}

@media (min-width: 900px) {
  .page-about .about-hero {
    grid-template-columns: minmax(0, 1.45fr) minmax(0, 0.6fr);
    gap: 3rem;
  }

  .page-about .about-timeline__track {
    grid-auto-columns: minmax(230px, 1fr);
    gap: 1.5rem;
  }
}

@media (min-width: 1040px) {
  .page-about .about-layout {
    grid-template-columns: minmax(0, 1fr) var(--about-rail);
    gap: 3.75rem;
    align-items: start;
  }

  .page-about .about-notes {
    order: 0;
  }

  .page-about .about-notes__inner {
    position: sticky;
    top: calc(var(--header-h) + 24px);
  }

  .page-about .about-hero {
    grid-template-columns: minmax(0, 1.5fr) minmax(0, 0.55fr);
  }
}

@media (min-width: 1200px) {
  .page-about {
    --about-rail: 288px;
  }

  .page-about .about-timeline__track {
    grid-auto-columns: minmax(0, 1fr);
    overflow-x: visible;
  }
}

@media (prefers-reduced-motion: reduce) {
  .page-about .room-block,
  .page-about .about-timeline__node,
  .page-about .about-timeline__dot,
  .page-about .about-timeline__more,
  .page-about .room-block__detail {
    transition: none;
  }

  .page-about .room-block:hover,
  .page-about .room-block:focus-within,
  .page-about .about-timeline__node:hover,
  .page-about .about-timeline__node:focus-within {
    transform: none;
  }
}