.page-about {
  --about-grid-gap: clamp(18px, 2.4vw, 30px);
  --about-pad: clamp(40px, 6vw, 84px);
  position: relative;
  background:
    radial-gradient(900px 520px at 10% -8%, rgba(94, 242, 214, 0.07), transparent 70%),
    radial-gradient(760px 480px at 94% 14%, rgba(138, 43, 226, 0.13), transparent 72%),
    var(--ink);
  color: var(--text);
  overflow-x: clip;
  padding-bottom: clamp(24px, 4vw, 48px);
}

.page-about .wrap {
  position: relative;
}

/* ---------- 首屏 ---------- */
.page-about .about-hero {
  position: relative;
  padding: clamp(36px, 6vw, 80px) 0 clamp(30px, 4.5vw, 56px);
  border-bottom: 1px solid var(--line);
}

.page-about .about-hero::before {
  content: "";
  position: absolute;
  inset: 0;
  background-image: repeating-linear-gradient(90deg, var(--line-soft) 0 1px, transparent 1px 54px);
  -webkit-mask-image: linear-gradient(180deg, rgba(0, 0, 0, 0.9), transparent 78%);
  mask-image: linear-gradient(180deg, rgba(0, 0, 0, 0.9), transparent 78%);
  pointer-events: none;
}

.page-about .about-hero .wrap {
  z-index: 1;
}

.page-about .hero-grid {
  display: grid;
  gap: var(--about-grid-gap);
  margin-top: clamp(18px, 2.6vw, 30px);
}

.page-about .hero-main h1 {
  font-family: var(--font-display);
  font-weight: 900;
  letter-spacing: -0.02em;
  font-size: clamp(29px, 5.2vw, 58px);
  line-height: 1.12;
  color: var(--text-strong);
  margin: 14px 0 18px;
  max-width: 16em;
}

.page-about .hero-main .lead {
  font-size: clamp(16px, 1.15vw, 19px);
  line-height: 1.85;
  color: var(--text);
  max-width: 44em;
  margin: 0;
}

.page-about .hero-aside {
  position: relative;
  border: 1px solid var(--line);
  border-radius: var(--radius-lg);
  padding: clamp(20px, 3vw, 30px);
  background:
    radial-gradient(320px 200px at 100% 0%, rgba(224, 36, 94, 0.24), transparent 70%),
    linear-gradient(158deg, rgba(138, 43, 226, 0.24), rgba(28, 23, 32, 0.9) 62%);
  overflow: hidden;
}

.page-about .hero-aside::before {
  content: "";
  position: absolute;
  left: 0;
  top: 0;
  bottom: 0;
  width: 3px;
  background: linear-gradient(180deg, var(--violet), var(--rose));
}

.page-about .hero-aside__label {
  margin: 0;
  font-size: 12px;
  letter-spacing: 0.1em;
  color: var(--mist);
}

.page-about .hero-aside__num {
  margin: 6px 0 8px;
  font-family: var(--font-mono);
  font-weight: 700;
  font-size: clamp(44px, 7vw, 72px);
  line-height: 1;
  letter-spacing: -0.03em;
  color: var(--text-strong);
}

.page-about .hero-aside__num span {
  font-size: 0.38em;
  margin-left: 6px;
  color: var(--amber);
}

.page-about .hero-aside__note {
  margin: 0 0 20px;
  font-size: 14px;
  line-height: 1.75;
  color: var(--text);
}

.page-about .hero-facts {
  list-style: none;
  margin: clamp(26px, 4vw, 44px) 0 0;
  padding: 0;
  display: grid;
  grid-template-columns: repeat(2, minmax(0, 1fr));
  gap: 1px;
  background: var(--line-soft);
  border: 1px solid var(--line-soft);
  border-radius: var(--radius-md);
  overflow: hidden;
}

.page-about .hero-facts li {
  display: grid;
  gap: 6px;
  padding: 16px 18px;
  background: rgba(28, 23, 32, 0.74);
}

.page-about .hero-facts .num {
  font-family: var(--font-mono);
  font-weight: 700;
  font-size: clamp(22px, 3vw, 32px);
  line-height: 1;
  letter-spacing: -0.02em;
  color: var(--mint);
}

.page-about .hero-facts__label {
  font-size: 13px;
  letter-spacing: 0.04em;
  color: var(--mist);
}

/* ---------- 章节骨架 ---------- */
.page-about .chapter {
  position: relative;
  padding: var(--about-pad) 0;
  border-top: 1px solid var(--line-soft);
}

.page-about .chapter__head {
  display: grid;
  grid-template-columns: auto minmax(0, 1fr);
  gap: clamp(14px, 2.4vw, 32px);
  align-items: start;
  margin-bottom: clamp(24px, 3.6vw, 48px);
}

.page-about .chapter__num {
  font-family: var(--font-mono);
  font-weight: 700;
  font-size: clamp(42px, 8vw, 86px);
  line-height: 0.82;
  letter-spacing: -0.05em;
  color: rgba(243, 233, 218, 0.08);
  transition: color 0.35s ease, text-shadow 0.35s ease;
}

.page-about .chapter.is-active .chapter__num {
  color: rgba(94, 242, 214, 0.9);
  text-shadow: 0 0 26px rgba(94, 242, 214, 0.3);
}

.page-about .chapter__title-block h2 {
  font-family: var(--font-display);
  font-weight: 900;
  letter-spacing: -0.015em;
  font-size: clamp(23px, 3.4vw, 38px);
  line-height: 1.24;
  color: var(--text-strong);
  margin: 10px 0 16px;
  max-width: 20em;
}

.page-about .chapter__rule {
  display: block;
  height: 3px;
  width: min(100%, 320px);
  border-radius: var(--radius-pill);
  background: linear-gradient(90deg, var(--orange), var(--amber) 36%, var(--mint) 70%, transparent);
}

/* ---------- 01 起点 ---------- */
.page-about .origin-grid {
  display: grid;
  gap: var(--about-grid-gap);
}

.page-about .origin-grid__text p {
  margin: 0 0 16px;
  font-size: 16px;
  line-height: 1.85;
  color: var(--text);
  max-width: 40em;
}

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

.page-about .origin-grid__text a {
  color: var(--mint);
  text-decoration: none;
  border-bottom: 1px solid var(--line-mint);
}

.page-about .origin-grid__text a:hover {
  color: var(--text-strong);
}

.page-about .origin-panel {
  border-radius: var(--radius-lg);
  padding: clamp(20px, 3vw, 30px);
  color: #2a1f18;
}

.page-about .origin-panel__label {
  margin: 0 0 14px;
  font-size: 12px;
  letter-spacing: 0.1em;
  color: rgba(42, 31, 24, 0.62);
}

.page-about .origin-panel__list {
  margin: 0;
  display: grid;
  gap: 0;
}

.page-about .origin-panel__list > div {
  display: grid;
  grid-template-columns: minmax(80px, auto) minmax(0, 1fr);
  gap: 12px 16px;
  align-items: baseline;
  padding: 12px 0;
  border-top: 1px solid rgba(42, 31, 24, 0.16);
}

.page-about .origin-panel__list > div:first-child {
  border-top: 0;
  padding-top: 0;
}

.page-about .origin-panel__list dt {
  font-family: var(--font-mono);
  font-weight: 700;
  font-size: clamp(20px, 2.4vw, 26px);
  letter-spacing: -0.02em;
  color: #17110f;
}

.page-about .origin-panel__list dd {
  margin: 0;
  font-size: 14px;
  line-height: 1.7;
  color: rgba(42, 31, 24, 0.72);
}

/* ---------- 02 编辑部 ---------- */
.page-about .desk-grid {
  display: grid;
  gap: clamp(20px, 3vw, 40px);
}

.page-about .desk-grid__media,
.page-about .service-grid__media,
.page-about .versions-banner {
  border-radius: var(--radius-md);
  border: 1px solid var(--line);
  overflow: hidden;
  background: var(--panel);
  margin: 0;
}

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

.page-about .media-frame__caption {
  padding: 10px 14px;
  font-size: 12px;
  letter-spacing: 0.06em;
  color: var(--mist);
  border-top: 1px solid var(--line-soft);
}

.page-about .desk-grid__text p {
  margin: 0 0 16px;
  font-size: 16px;
  line-height: 1.85;
  color: var(--text);
  max-width: 40em;
}

.page-about .shift-list {
  margin: 24px 0 0;
  display: grid;
  gap: 0;
}

.page-about .shift-list > div {
  display: grid;
  grid-template-columns: 62px minmax(0, 1fr);
  gap: 8px 16px;
  align-items: baseline;
  padding: 13px 0;
  border-top: 1px dashed var(--line);
}

.page-about .shift-list dt {
  font-family: var(--font-mono);
  font-size: 13px;
  letter-spacing: 0.1em;
  color: var(--amber);
}

.page-about .shift-list dd {
  margin: 0;
  font-size: 15px;
  line-height: 1.75;
  color: var(--text);
}

/* ---------- 03 版本演进 ---------- */
.page-about .chapter--versions .versions-banner {
  margin-bottom: clamp(26px, 4vw, 44px);
}

.page-about .timeline {
  list-style: none;
  margin: 0;
  padding: 0;
  display: grid;
  gap: 18px;
}

.page-about .timeline__node {
  position: relative;
  padding-left: 30px;
}

.page-about .timeline__node::before {
  content: "";
  position: absolute;
  left: 6px;
  top: 20px;
  bottom: -18px;
  width: 2px;
  background: linear-gradient(180deg, var(--track), transparent);
}

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

.page-about .timeline__dot {
  position: absolute;
  left: 0;
  top: 4px;
  width: 14px;
  height: 14px;
  border-radius: 50%;
  background: var(--ink);
  border: 2px solid var(--mint);
  box-shadow: 0 0 0 4px rgba(94, 242, 214, 0.12);
}

.page-about .tl-item {
  border: 1px solid var(--line);
  border-radius: var(--radius-md);
  background: rgba(28, 23, 32, 0.62);
  padding: 14px 16px 16px;
  transition: border-color 0.25s ease, background 0.25s ease;
}

.page-about .tl-item[open] {
  border-color: var(--line-mint);
  background: rgba(28, 23, 32, 0.94);
}

.page-about .tl-item > summary {
  list-style: none;
  cursor: pointer;
  display: flex;
  flex-wrap: wrap;
  align-items: baseline;
  gap: 6px 14px;
}

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

.page-about .tl-item > summary::after {
  content: "展开";
  margin-left: auto;
  font-size: 12px;
  letter-spacing: 0.12em;
  color: var(--mist);
}

.page-about .tl-item[open] > summary::after {
  content: "收起";
  color: var(--mint);
}

.page-about .tl-item__ver {
  font-family: var(--font-mono);
  font-weight: 700;
  font-size: clamp(20px, 2.2vw, 26px);
  letter-spacing: -0.02em;
  color: var(--orange);
}

.page-about .tl-item__phase {
  font-family: var(--font-display);
  font-weight: 900;
  font-size: 15px;
  letter-spacing: 0.02em;
  color: var(--text-strong);
}

.page-about .tl-item p {
  margin: 12px 0 0;
  font-size: 15px;
  line-height: 1.8;
  color: var(--text);
  max-width: 52em;
}

/* ---------- 04 服务覆盖与规模 ---------- */
.page-about .scale-grid {
  display: grid;
  gap: var(--about-grid-gap);
}

.page-about .scale-card {
  position: relative;
  display: grid;
  gap: 10px;
  align-content: start;
  padding: clamp(20px, 2.6vw, 30px);
  border-radius: var(--radius-lg);
  border: 1px solid var(--line);
  background: linear-gradient(155deg, rgba(28, 23, 32, 0.96), rgba(28, 23, 32, 0.58));
  overflow: hidden;
}

.page-about .scale-card::after {
  content: "";
  position: absolute;
  left: 0;
  top: 0;
  bottom: 0;
  width: 3px;
  background: linear-gradient(180deg, var(--mint), transparent);
  opacity: 0.7;
}

.page-about .scale-card--cream {
  background: var(--cream);
  border-color: transparent;
}

.page-about .scale-card--cream::after {
  background: linear-gradient(180deg, var(--violet), var(--rose));
}

.page-about .scale-card__label {
  margin: 0;
  font-size: 12px;
  letter-spacing: 0.1em;
  color: var(--mist);
}

.page-about .scale-card__num {
  margin: 0;
  font-family: var(--font-mono);
  font-weight: 700;
  font-size: clamp(34px, 5.2vw, 58px);
  line-height: 1;
  letter-spacing: -0.03em;
  color: var(--text-strong);
}

.page-about .scale-card__num span {
  font-size: 0.4em;
  margin-left: 6px;
  color: var(--mint);
}

.page-about .scale-card--cream .scale-card__label {
  color: rgba(42, 31, 24, 0.62);
}

.page-about .scale-card--cream .scale-card__num {
  color: #17110f;
}

.page-about .scale-card--cream .scale-card__num span {
  color: var(--rose);
}

.page-about .scale-card--cream .scale-card__note {
  color: rgba(42, 31, 24, 0.74);
}

.page-about .scale-card__note {
  margin: 0;
  font-size: 14px;
  line-height: 1.75;
  color: var(--text);
}

.page-about .scale-card__pair {
  margin: 0;
  display: flex;
  flex-wrap: wrap;
  gap: 10px 26px;
}

.page-about .scale-card__pair > span {
  display: grid;
  gap: 2px;
  font-family: var(--font-mono);
  font-weight: 700;
  font-size: clamp(28px, 3.4vw, 38px);
  line-height: 1;
  letter-spacing: -0.02em;
  color: var(--amber);
}

.page-about .scale-card__pair i {
  font-style: normal;
  font-family: var(--font-display);
  font-weight: 500;
  font-size: 12px;
  letter-spacing: 0.08em;
  color: var(--mist);
}

.page-about .scale-foot {
  margin: clamp(22px, 3vw, 34px) 0 0;
  padding-left: 16px;
  border-left: 3px solid var(--amber);
  font-size: 15px;
  line-height: 1.85;
  color: var(--text);
  max-width: 62em;
}

/* ---------- 05 团队分工 ---------- */
.page-about .service-grid {
  display: grid;
  gap: clamp(20px, 3vw, 40px);
}

.page-about .service-grid__text p {
  margin: 0 0 16px;
  font-size: 16px;
  line-height: 1.85;
  color: var(--text);
  max-width: 40em;
}

.page-about .promise-list {
  list-style: none;
  margin: 24px 0 0;
  padding: 0;
  display: grid;
  gap: 1px;
  background: var(--line-soft);
  border: 1px solid var(--line-soft);
  border-radius: var(--radius-md);
  overflow: hidden;
}

.page-about .promise-list li {
  display: grid;
  grid-template-columns: 92px minmax(0, 1fr);
  gap: 6px 16px;
  align-items: baseline;
  padding: 13px 16px;
  background: rgba(28, 23, 32, 0.78);
}

.page-about .promise-list__k {
  font-size: 13px;
  letter-spacing: 0.08em;
  color: var(--mist);
}

.page-about .promise-list__v {
  font-size: 15px;
  line-height: 1.7;
  color: var(--text-strong);
}

/* ---------- 06 长期留下 ---------- */
.page-about .stay-list {
  list-style: none;
  margin: 0;
  padding: 0;
  display: grid;
  gap: var(--about-grid-gap);
}

.page-about .stay-list li {
  position: relative;
  padding: clamp(20px, 2.6vw, 30px);
  border-radius: var(--radius-lg);
  border: 1px solid var(--line);
  background: linear-gradient(160deg, rgba(28, 23, 32, 0.95), rgba(28, 23, 32, 0.6));
  overflow: hidden;
}

.page-about .stay-list li::before {
  content: "";
  position: absolute;
  right: -60px;
  top: -60px;
  width: 180px;
  height: 180px;
  border-radius: 50%;
  background: radial-gradient(circle, rgba(255, 90, 43, 0.16), transparent 68%);
  pointer-events: none;
}

.page-about .stay-list__tag {
  margin: 0 0 10px;
  font-size: 12px;
  letter-spacing: 0.12em;
  color: var(--orange);
}

.page-about .stay-list h3 {
  font-family: var(--font-display);
  font-weight: 900;
  font-size: clamp(18px, 2.2vw, 23px);
  line-height: 1.35;
  color: var(--text-strong);
  margin: 0 0 12px;
  letter-spacing: -0.01em;
}

.page-about .stay-list p {
  margin: 0;
  font-size: 15px;
  line-height: 1.85;
  color: var(--text);
}

.page-about .stay-close {
  margin: clamp(24px, 3vw, 36px) 0 0;
  font-size: 15px;
  line-height: 1.85;
  color: var(--text);
}

.page-about .stay-close a {
  color: var(--mint);
  text-decoration: none;
  border-bottom: 1px solid var(--line-mint);
}

.page-about .stay-close a:hover {
  color: var(--text-strong);
}

/* ---------- 结尾行动区 ---------- */
.page-about .about-cta {
  padding: 0 0 clamp(40px, 6vw, 72px);
}

.page-about .about-cta__box {
  position: relative;
  padding: clamp(26px, 4vw, 52px);
  border-radius: var(--radius-lg);
  border: 1px solid var(--line);
  background:
    radial-gradient(600px 320px at 88% 0%, rgba(224, 36, 94, 0.3), transparent 70%),
    linear-gradient(150deg, rgba(138, 43, 226, 0.3), rgba(18, 15, 20, 0.92) 62%);
  overflow: hidden;
}

.page-about .about-cta__box h2 {
  font-family: var(--font-display);
  font-weight: 900;
  letter-spacing: -0.015em;
  font-size: clamp(22px, 3vw, 34px);
  line-height: 1.28;
  color: var(--text-strong);
  margin: 12px 0 14px;
  max-width: 20em;
}

.page-about .about-cta__text {
  margin: 0;
  font-size: 16px;
  line-height: 1.85;
  color: var(--text);
  max-width: 46em;
}

.page-about .about-cta__actions {
  display: flex;
  flex-wrap: wrap;
  gap: 12px;
  margin-top: clamp(20px, 3vw, 30px);
}

/* ---------- 响应式 ---------- */
@media (min-width: 640px) {
  .page-about .hero-facts {
    grid-template-columns: repeat(4, minmax(0, 1fr));
  }
}

@media (min-width: 860px) {
  .page-about .scale-grid {
    grid-template-columns: repeat(6, minmax(0, 1fr));
  }

  .page-about .scale-card--lead {
    grid-column: span 3;
  }

  .page-about .scale-card--cream {
    grid-column: span 3;
  }

  .page-about .scale-card--pair {
    grid-column: span 6;
    grid-template-columns: minmax(0, auto) minmax(0, 1fr);
    align-items: center;
    column-gap: clamp(24px, 4vw, 56px);
  }

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

  .page-about .stay-list > li:first-child {
    grid-column: 1 / -1;
    display: grid;
    grid-template-columns: minmax(0, 1fr) minmax(0, 1fr);
    grid-template-areas:
      "tag copy"
      "title copy";
    align-content: center;
    gap: 6px clamp(24px, 4vw, 44px);
  }

  .page-about .stay-list > li:first-child .stay-list__tag {
    grid-area: tag;
    margin-bottom: 0;
  }

  .page-about .stay-list > li:first-child h3 {
    grid-area: title;
    margin-bottom: 0;
  }

  .page-about .stay-list > li:first-child p {
    grid-area: copy;
    align-self: center;
  }
}

@media (min-width: 960px) {
  .page-about .hero-grid {
    grid-template-columns: minmax(0, 1.55fr) minmax(280px, 0.85fr);
    align-items: end;
    gap: clamp(28px, 4vw, 56px);
  }

  .page-about .origin-grid {
    grid-template-columns: minmax(0, 1.45fr) minmax(280px, 0.8fr);
    gap: clamp(24px, 4vw, 56px);
    align-items: start;
  }

  .page-about .desk-grid {
    grid-template-columns: minmax(0, 1.05fr) minmax(0, 1fr);
    align-items: start;
  }

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

  .page-about .service-grid {
    grid-template-columns: minmax(0, 1fr) minmax(0, 0.95fr);
    align-items: start;
  }

  .page-about .chapter__head {
    align-items: end;
  }
}

@media (min-width: 1024px) {
  .page-about .timeline {
    position: relative;
    grid-template-columns: repeat(4, minmax(0, 1fr));
    gap: clamp(14px, 1.7vw, 22px);
  }

  .page-about .timeline::before {
    content: "";
    position: absolute;
    left: 0;
    right: 0;
    top: 7px;
    height: 2px;
    border-radius: var(--radius-pill);
    background: linear-gradient(90deg, var(--orange), var(--amber) 34%, var(--mint) 68%, var(--violet));
    opacity: 0.55;
  }

  .page-about .timeline__node {
    padding-left: 0;
    padding-top: 42px;
  }

  .page-about .timeline__node::before {
    display: none;
  }

  .page-about .timeline__dot {
    left: 0;
    top: 0;
    width: 16px;
    height: 16px;
    border-color: var(--amber);
    box-shadow: 0 0 0 5px rgba(255, 197, 61, 0.12);
  }

  .page-about .timeline__node:nth-child(2) .timeline__dot {
    border-color: var(--mint);
    box-shadow: 0 0 0 5px rgba(94, 242, 214, 0.12);
  }

  .page-about .timeline__node:nth-child(3) .timeline__dot {
    border-color: var(--orange);
    box-shadow: 0 0 0 5px rgba(255, 90, 43, 0.14);
  }

  .page-about .timeline__node:nth-child(4) .timeline__dot {
    border-color: var(--violet);
    box-shadow: 0 0 0 5px rgba(138, 43, 226, 0.16);
  }
}

@media (prefers-reduced-motion: reduce) {
  .page-about .chapter__num,
  .page-about .tl-item {
    transition: none;
  }
}