.page-about {
  --about-line: rgba(21, 21, 21, .14);
  --about-line-soft: rgba(21, 21, 21, .07);
  --about-paper-line: rgba(247, 241, 230, .18);
  background: var(--paper);
  color: var(--ink);
  overflow-x: clip;
}

/* ---------- 首屏 ---------- */

.page-about .about-hero {
  position: relative;
  padding-block: clamp(1.8rem, 5vw, 3.2rem) clamp(2rem, 5vw, 3.6rem);
  background:
    radial-gradient(circle at 88% 6%, rgba(217, 164, 65, .22), transparent 46%),
    linear-gradient(180deg, #FBF7EE 0%, var(--paper) 76%);
  overflow: hidden;
}

.page-about .about-hero::after {
  content: "";
  position: absolute;
  inset-inline-end: -14%;
  inset-block-start: 22%;
  width: min(56vw, 480px);
  aspect-ratio: 1;
  border: 1px solid rgba(200, 16, 46, .18);
  border-radius: 50%;
  box-shadow: 0 0 0 26px rgba(217, 164, 65, .07);
  pointer-events: none;
}

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

.page-about .breadcrumb {
  margin-bottom: clamp(1.4rem, 3vw, 2.2rem);
}

.page-about .about-kicker {
  display: flex;
  align-items: center;
  gap: .65rem;
  margin: 0 0 1.1rem;
  font-size: .8rem;
  font-weight: 700;
  letter-spacing: .16em;
  color: var(--muted-ink);
}

.page-about .about-kicker__line {
  display: block;
  width: 34px;
  height: 2px;
  background: var(--red);
}

.page-about .about-hero__lead {
  display: grid;
  gap: 1.4rem;
}

.page-about .about-title {
  margin: 0;
  max-width: 15ch;
  font-family: var(--font-display);
  font-weight: 900;
  font-size: clamp(2rem, 7vw, 4.2rem);
  line-height: 1.04;
  letter-spacing: -.025em;
  color: var(--ink);
}

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

.page-about .about-hero__text p {
  margin: 0 0 .9rem;
  font-size: clamp(.95rem, 2.2vw, 1.02rem);
  line-height: 1.85;
  color: var(--muted-ink);
}

.page-about .about-hero__text .btn {
  margin-top: .5rem;
}

.page-about .about-stats {
  display: grid;
  grid-template-columns: repeat(2, minmax(0, 1fr));
  gap: 1px;
  margin: clamp(1.9rem, 4vw, 3rem) 0 0;
  background: var(--about-line);
  border-block: 1px solid var(--about-line);
}

.page-about .about-stats > div {
  background: var(--paper);
  padding: .85rem .95rem 1rem;
}

.page-about .about-stats dt {
  font-size: .72rem;
  letter-spacing: .12em;
  color: var(--muted-ink);
  margin-bottom: .35rem;
}

.page-about .about-stats dd {
  margin: 0;
  font-family: var(--font-mono);
  font-size: .84rem;
  color: var(--muted-ink);
  letter-spacing: .02em;
}

.page-about .about-stat__num {
  display: inline-block;
  margin-inline-end: .18rem;
  font-size: 1.6rem;
  font-weight: 600;
  line-height: 1;
  color: var(--red);
  letter-spacing: -.02em;
}

/* ---------- 章节通用骨架 ---------- */

.page-about .sec {
  position: relative;
  padding-block: clamp(2.4rem, 6vw, 4.6rem);
}

.page-about .sec + .sec {
  border-top: 1px solid var(--about-line-soft);
}

.page-about .sec__grid {
  display: grid;
  grid-template-columns: minmax(0, 1fr);
  gap: 1.1rem;
}

.page-about .sec__aside {
  display: flex;
  align-items: baseline;
  gap: .75rem;
  order: -1;
}

.page-about .sec__aside .annotation {
  margin: 0;
  font-size: .74rem;
  font-weight: 700;
  letter-spacing: .2em;
  color: var(--red);
  white-space: nowrap;
}

.page-about .sec__index {
  margin: 0;
  font-family: var(--font-mono);
  font-size: 1.9rem;
  font-weight: 600;
  line-height: 1;
  letter-spacing: -.04em;
  color: transparent;
  -webkit-text-stroke: 1px rgba(200, 16, 46, .45);
}

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

.page-about .sec__title {
  margin: 0 0 1rem;
  font-family: var(--font-display);
  font-weight: 900;
  font-size: clamp(1.45rem, 4.4vw, 2.4rem);
  line-height: 1.18;
  letter-spacing: -.018em;
}

.page-about .sec__lead {
  margin: 0 0 1.5rem;
  max-width: 54ch;
  font-size: .95rem;
  line-height: 1.8;
  color: var(--muted-ink);
}

.page-about .sec__body p {
  margin: 0 0 1rem;
  max-width: 62ch;
  font-size: .96rem;
  line-height: 1.88;
  color: var(--ink);
}

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

.page-about .sec__body--drop > p:first-of-type::first-letter {
  float: left;
  font-family: var(--font-display);
  font-weight: 900;
  font-size: 3.3em;
  line-height: .84;
  margin-inline-end: .1em;
  margin-block-start: .06em;
  color: var(--red);
}

.page-about .sec__note {
  margin: 1.4rem 0 0;
  padding-inline-start: .95rem;
  border-inline-start: 3px solid var(--gold);
  font-size: .88rem;
  line-height: 1.75;
  color: var(--muted-ink);
  max-width: 52ch;
}

/* ---------- 01 品牌由来 ---------- */

.page-about .origin-body {
  display: grid;
  gap: 1.5rem;
  margin-top: .4rem;
}

/* ---------- 图片 ---------- */

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

.page-about .about-figure__frame {
  position: relative;
  background: var(--ink);
  overflow: hidden;
  clip-path: polygon(0 0, 100% 0, 100% calc(100% - 22px), calc(100% - 22px) 100%, 0 100%);
}

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

.page-about .about-figure--square .about-figure__frame {
  border-inline-end: 4px solid var(--red);
}

.page-about .about-figure figcaption {
  margin-top: .6rem;
  font-size: .76rem;
  line-height: 1.6;
  letter-spacing: .02em;
  color: var(--muted-ink);
}

/* ---------- 02 三件做法 ---------- */

.page-about .principles {
  list-style: none;
  margin: 1.4rem 0 0;
  padding: 0;
  display: grid;
  gap: .8rem;
}

.page-about .principle {
  display: grid;
  grid-template-columns: auto minmax(0, 1fr);
  gap: .9rem;
  padding: 1.1rem 1.15rem 1.2rem;
  background: var(--white);
  border-inline-start: 3px solid var(--red);
  clip-path: polygon(0 0, 100% 0, 100% calc(100% - 16px), calc(100% - 16px) 100%, 0 100%);
}

.page-about .principle__num {
  font-family: var(--font-mono);
  font-size: .9rem;
  font-weight: 600;
  letter-spacing: .08em;
  color: var(--gold);
  padding-block-start: .2rem;
}

.page-about .principle__title {
  margin: 0 0 .45rem;
  font-family: var(--font-display);
  font-weight: 900;
  font-size: 1.05rem;
  line-height: 1.4;
  letter-spacing: -.01em;
}

.page-about .principle p {
  margin: 0;
  font-size: .92rem;
  line-height: 1.8;
  color: var(--muted-ink);
}

/* ---------- 03 团队 ---------- */

.page-about .team-list {
  list-style: none;
  margin: 1.4rem 0 1.6rem;
  padding: 0;
  display: grid;
  gap: 1px;
  background: var(--about-line);
  border-block: 1px solid var(--about-line);
}

.page-about .team-item {
  background: var(--paper);
  padding: 1.05rem 0 1.15rem;
}

.page-about .team-item__name {
  margin: 0 0 .45rem;
  font-family: var(--font-display);
  font-weight: 900;
  font-size: 1.02rem;
  letter-spacing: -.01em;
  color: var(--red);
}

.page-about .team-item p {
  margin: 0;
  max-width: 60ch;
  font-size: .92rem;
  line-height: 1.82;
  color: var(--muted-ink);
}

/* ---------- 04 版本演进（深色） ---------- */

.page-about .sec--dark {
  background: var(--ink);
  color: var(--paper);
  border-top: none;
}

.page-about .sec--dark::before {
  content: "";
  position: absolute;
  inset-block-start: 0;
  inset-inline: 0;
  height: 4px;
  background: linear-gradient(90deg, var(--red) 0%, var(--gold) 46%, var(--red-deep) 100%);
}

.page-about .sec--dark .sec__title {
  color: var(--paper);
}

.page-about .sec--dark .sec__lead {
  color: rgba(247, 241, 230, .72);
}

.page-about .sec--dark .annotation--light {
  color: var(--gold-light);
}

.page-about .sec--dark .sec__index--light {
  -webkit-text-stroke: 1px rgba(217, 164, 65, .55);
}

.page-about .timeline {
  list-style: none;
  margin: 1.6rem 0 0;
  padding: 0;
}

.page-about .timeline__item {
  position: relative;
  padding: 0 0 1.8rem 1.9rem;
}

.page-about .timeline__item::before {
  content: "";
  position: absolute;
  inset-inline-start: .42rem;
  inset-block: .55rem -.1rem;
  width: 2px;
  background: linear-gradient(180deg, var(--gold), rgba(247, 241, 230, .16));
}

.page-about .timeline__item:last-child::before {
  display: none;
}

.page-about .timeline__item::after {
  content: "";
  position: absolute;
  inset-inline-start: .01rem;
  inset-block-start: .4rem;
  width: .74rem;
  height: .74rem;
  border-radius: 50%;
  background: var(--red);
  box-shadow: 0 0 0 4px var(--ink);
}

.page-about .timeline__ver {
  display: inline-block;
  margin-bottom: .55rem;
  padding: .18rem .5rem;
  font-family: var(--font-mono);
  font-size: .72rem;
  letter-spacing: .14em;
  color: var(--ink);
  background: var(--gold-light);
}

.page-about .timeline__title {
  margin: 0 0 .5rem;
  font-family: var(--font-display);
  font-weight: 900;
  font-size: 1.08rem;
  line-height: 1.42;
  color: var(--paper);
}

.page-about .timeline__item p {
  margin: 0;
  max-width: 58ch;
  font-size: .92rem;
  line-height: 1.85;
  color: rgba(247, 241, 230, .74);
}

.page-about .timeline__outro {
  margin: 0;
  padding-block-start: 1.1rem;
  border-top: 1px solid var(--about-paper-line);
  font-family: var(--font-mono);
  font-size: .8rem;
  line-height: 1.7;
  letter-spacing: .02em;
  color: var(--gold-light);
}

/* ---------- 05 审核 ------ */

.page-about .checks {
  display: grid;
  gap: .7rem;
  margin-top: 1.4rem;
}

.page-about .check {
  background: var(--white);
  border: 1px solid var(--about-line);
  padding: .85rem 1rem;
  clip-path: polygon(0 0, 100% 0, 100% calc(100% - 12px), calc(100% - 12px) 100%, 0 100%);
}

.page-about .check > summary {
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: .8rem;
  cursor: pointer;
  list-style: none;
  font-size: .95rem;
  font-weight: 700;
  line-height: 1.5;
  color: var(--ink);
}

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

.page-about .check > summary::after {
  content: "+";
  flex: none;
  font-family: var(--font-mono);
  font-size: 1.1rem;
  line-height: 1;
  color: var(--red);
}

.page-about .check[open] > summary::after {
  content: "−";
}

.page-about .check > summary:focus-visible {
  outline: 2px solid var(--red);
  outline-offset: 3px;
}

.page-about .check p {
  margin: .65rem 0 0;
  font-size: .9rem;
  line-height: 1.8;
  color: var(--muted-ink);
}

/* ---------- 06 地域符号 ---------- */

.page-about .symbols {
  display: grid;
  gap: .55rem;
  margin-top: 1.3rem;
  padding-top: 1.1rem;
  border-top: 1px solid var(--about-line);
}

.page-about .symbols__item {
  display: flex;
  align-items: baseline;
  gap: .6rem;
  margin: 0;
  font-size: .85rem;
  line-height: 1.7;
  color: var(--muted-ink);
}

.page-about .symbols__dot {
  flex: none;
  width: .5rem;
  height: .5rem;
  border-radius: 50%;
  transform: translateY(-1px);
}

.page-about .symbols__dot--red {
  background: var(--red);
}

.page-about .symbols__dot--gold {
  background: var(--gold);
}

.page-about .symbols__dot--ink {
  background: var(--ink);
}

/* ---------- 目录折叠 ---------- */

.page-about .about-toc {
  margin-top: 1.6rem;
  border-top: 1px solid var(--about-line);
  padding-top: .9rem;
}

.page-about .about-toc > summary {
  cursor: pointer;
  list-style: none;
  display: inline-flex;
  align-items: center;
  gap: .5rem;
  font-size: .82rem;
  font-weight: 700;
  letter-spacing: .1em;
  color: var(--red);
}

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

.page-about .about-toc > summary::before {
  content: "＋";
  font-family: var(--font-mono);
  font-size: .9rem;
}

.page-about .about-toc[open] > summary::before {
  content: "－";
}

.page-about .about-toc > summary:focus-visible {
  outline: 2px solid var(--red);
  outline-offset: 3px;
}

.page-about .about-toc ol {
  list-style: none;
  margin: .85rem 0 0;
  padding: 0;
  display: grid;
  gap: .1rem;
}

.page-about .about-toc li a {
  display: block;
  padding: .5rem .2rem;
  font-size: .88rem;
  color: var(--ink);
  text-decoration: none;
  border-bottom: 1px dashed var(--about-line);
}

.page-about .about-toc li a:hover,
.page-about .about-toc li a:focus-visible {
  color: var(--red);
}

/* ---------- 下一步 ---------- */

.page-about .about-next {
  position: relative;
  padding-block: clamp(2.4rem, 6vw, 4rem);
  background:
    linear-gradient(135deg, rgba(200, 16, 46, .07) 0%, rgba(217, 164, 65, .1) 60%, transparent 100%);
  border-top: 1px solid var(--about-line);
}

.page-about .about-next__title {
  margin: 0 0 1.3rem;
  font-family: var(--font-display);
  font-weight: 900;
  font-size: clamp(1.35rem, 4vw, 2rem);
  line-height: 1.2;
  letter-spacing: -.015em;
}

.page-about .next-links {
  list-style: none;
  margin: 0;
  padding: 0;
  display: grid;
  gap: 1px;
  background: var(--about-line);
  border-block: 1px solid var(--about-line);
}

.page-about .next-links li {
  background: var(--paper);
}

.page-about .next-links a {
  display: grid;
  grid-template-columns: minmax(0, 1fr) auto;
  align-items: center;
  gap: .25rem 1rem;
  padding: .95rem .2rem;
  text-decoration: none;
  color: var(--ink);
}

.page-about .next-links__label {
  font-family: var(--font-display);
  font-weight: 900;
  font-size: 1rem;
  letter-spacing: -.01em;
}

.page-about .next-links__desc {
  grid-column: 1 / 2;
  font-size: .82rem;
  line-height: 1.6;
  color: var(--muted-ink);
}

.page-about .next-links__arrow {
  grid-row: 1 / 3;
  grid-column: 2 / 3;
  font-family: var(--font-mono);
  font-size: 1.05rem;
  color: var(--red);
  transition: transform .2s var(--ease);
}

.page-about .next-links a:hover .next-links__label,
.page-about .next-links a:focus-visible .next-links__label {
  color: var(--red);
}

.page-about .next-links a:hover .next-links__arrow,
.page-about .next-links a:focus-visible .next-links__arrow {
  transform: translateX(4px);
}

/* ---------- 中等屏 ---------- */

@media (min-width: 640px) {
  .page-about .about-stats {
    grid-template-columns: repeat(3, minmax(0, 1fr));
  }

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

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

  .page-about .team-list {
    grid-template-columns: repeat(3, minmax(0, 1fr));
    gap: 0;
    border-block: none;
    background: transparent;
  }

  .page-about .team-item {
    padding: 1.05rem 1.1rem 1.15rem;
    border-top: 1px solid var(--about-line);
    border-bottom: 1px solid var(--about-line);
    border-inline-start: 1px solid var(--about-line);
  }

  .page-about .team-item:first-child {
    padding-inline-start: 0;
    border-inline-start: none;
  }

  .page-about .team-item:last-child {
    padding-inline-end: 0;
  }

  .page-about .symbols {
    grid-template-columns: repeat(3, minmax(0, 1fr));
    gap: .8rem 1.2rem;
  }
}

/* ---------- 桌面 ---------- */

@media (min-width: 900px) {
  .page-about .about-hero__lead {
    grid-template-columns: minmax(0, 1.12fr) minmax(0, .88fr);
    gap: clamp(1.8rem, 4vw, 3.6rem);
    align-items: end;
  }

  .page-about .about-title {
    max-width: 14ch;
  }

  .page-about .about-stats {
    grid-template-columns: repeat(5, minmax(0, 1fr));
  }

  .page-about .sec__grid {
    grid-template-columns: 118px minmax(0, 1fr);
    gap: clamp(1.6rem, 3.4vw, 3rem);
    align-items: start;
  }

  .page-about .sec__aside {
    display: block;
    position: sticky;
    top: calc(var(--topbar) + 1.6rem);
  }

  .page-about .sec__aside .annotation {
    writing-mode: vertical-rl;
    letter-spacing: .34em;
    margin-bottom: 1.1rem;
    padding-inline-start: 6px;
    border-inline-start: 2px solid var(--gold);
  }

  .page-about .sec__index {
    font-size: 2.6rem;
  }

  .page-about .origin-body {
    grid-template-columns: minmax(0, 1.08fr) minmax(0, .92fr);
    gap: clamp(1.6rem, 3.2vw, 2.8rem);
    align-items: start;
    margin-top: .6rem;
  }

  .page-about .sec__body--drop > p:first-of-type::first-letter {
    font-size: 3.9em;
  }

  .page-about .checks {
    margin-top: 1.6rem;
  }

  .page-about .next-links {
    grid-template-columns: repeat(4, minmax(0, 1fr));
    border-block: none;
    background: transparent;
    gap: 0;
  }

  .page-about .next-links a {
    padding: 1.1rem 1.1rem 1.2rem;
  }

  .page-about .next-links li {
    border-top: 2px solid var(--red);
    border-bottom: 1px solid var(--about-line);
    border-inline-start: 1px solid var(--about-line);
    background: rgba(255, 255, 255, .5);
  }

  .page-about .next-links li:last-child {
    border-inline-end: 1px solid var(--about-line);
  }

  .page-about .next-links__arrow {
    grid-row: 1 / 3;
  }

  .page-about .about-toc ol {
    grid-template-columns: repeat(3, minmax(0, 1fr));
    column-gap: 1.6rem;
  }
}

@media (prefers-reduced-motion: reduce) {
  .page-about .next-links__arrow {
    transition: none;
  }
}