.page-about {
  --about-num-size: clamp(2.2rem, 6vw, 4.2rem);
  display: block;
}

.page-about .about-crumb {
  padding-block: 18px 0;
}

/* ---------- 首屏 ---------- */
.page-about .about-hero {
  position: relative;
  overflow: hidden;
  padding-block: clamp(28px, 5vw, 56px) clamp(48px, 8vw, 96px);
}

.page-about .about-hero__slant {
  position: absolute;
  inset-block-start: -14%;
  inset-inline-end: -22%;
  width: min(600px, 70vw);
  aspect-ratio: 3 / 4;
  background: linear-gradient(150deg, rgba(0, 229, 208, .18), rgba(255, 106, 43, .12) 56%, transparent 76%);
  clip-path: polygon(30% 0, 100% 0, 100% 100%, 0 100%);
  pointer-events: none;
  z-index: 0;
}

.page-about .about-hero__inner {
  position: relative;
  z-index: 1;
  display: grid;
  gap: clamp(26px, 5vw, 56px);
}

.page-about .about-hero__title {
  margin: .28em 0 0;
  font-family: var(--font-sans);
  font-weight: 900;
  font-size: clamp(2.3rem, 6.6vw, 4.6rem);
  line-height: 1.06;
  letter-spacing: .02em;
  color: var(--paper);
}

.page-about .about-hero__accent {
  color: var(--cyan);
}

.page-about .about-hero__lede {
  margin: 0 0 clamp(22px, 4vw, 32px);
  color: var(--mist);
  max-width: 36em;
}

.page-about .about-hero__stats {
  list-style: none;
  margin: 0 0 clamp(20px, 4vw, 28px);
  padding: 16px 0 0;
  display: grid;
  grid-template-columns: repeat(3, minmax(0, 1fr));
  gap: 10px;
  border-top: 1px solid var(--line-strong);
}

.page-about .about-stat {
  display: grid;
  gap: 4px;
}

.page-about .about-stat__num {
  font-family: var(--font-mono);
  font-size: clamp(1.05rem, 3.2vw, 1.5rem);
  letter-spacing: .02em;
  color: var(--cyan);
}

.page-about .about-stat__label {
  font-size: clamp(.66rem, 2.2vw, .8rem);
  color: var(--steel);
  letter-spacing: .04em;
}

@media (min-width: 900px) {
  .page-about .about-hero__inner {
    grid-template-columns: minmax(0, 1.15fr) minmax(0, .85fr);
    align-items: end;
  }
  .page-about .about-stat__label {
    font-size: .8rem;
  }
}

/* ---------- 章节索引 ---------- */
.page-about .about-index {
  position: sticky;
  top: 0;
  z-index: 1;
  background: var(--ink-800);
  border-block: 1px solid var(--line);
}

.page-about .about-index__inner {
  display: flex;
  gap: clamp(14px, 3vw, 34px);
  overflow-x: auto;
  padding-block: 12px;
  scrollbar-width: thin;
}

.page-about .about-index__link {
  display: inline-flex;
  align-items: baseline;
  gap: .5em;
  white-space: nowrap;
  flex: 0 0 auto;
  padding-bottom: 2px;
  border-bottom: 1px solid transparent;
  color: var(--mist);
  text-decoration: none;
  font-size: .84rem;
  transition: color var(--dur) var(--ease), border-color var(--dur) var(--ease);
}

.page-about .about-index__link .mono {
  font-size: .72rem;
  color: var(--steel);
}

.page-about .about-index__link:hover,
.page-about .about-index__link:focus-visible {
  color: var(--paper);
  border-bottom-color: var(--cyan-line);
}

.page-about .about-index__link:hover .mono,
.page-about .about-index__link:focus-visible .mono {
  color: var(--cyan);
}

/* ---------- 章节骨架 ---------- */
.page-about .about-chapter {
  display: grid;
  gap: clamp(14px, 2.6vw, 26px);
  padding-block: clamp(46px, 8vw, 92px);
  border-top: 1px solid var(--line);
}

.page-about .about-chapter--last {
  padding-bottom: clamp(56px, 10vw, 110px);
}

.page-about .about-chapter__rail {
  display: flex;
  align-items: flex-start;
}

.page-about .about-chapter__num {
  font-size: var(--about-num-size);
  line-height: .9;
  letter-spacing: .04em;
  color: rgba(0, 229, 208, .34);
  position: relative;
  padding-inline-end: 14px;
}

.page-about .about-chapter__num::after {
  content: "";
  position: absolute;
  inset-block-start: 0;
  inset-inline-end: 0;
  width: 3px;
  height: 1.1em;
  background: var(--amber);
  border-radius: 2px;
}

@media (min-width: 880px) {
  .page-about .about-chapter {
    grid-template-columns: 96px minmax(0, 1fr);
    column-gap: clamp(26px, 5vw, 72px);
  }
  .page-about .about-chapter__num {
    position: sticky;
    top: 72px;
  }
}

.page-about .section-head__title {
  margin: .1em 0 .5em;
  font-size: clamp(1.5rem, 3.6vw, 2.3rem);
  line-height: 1.24;
  letter-spacing: .01em;
  color: var(--paper);
}

.page-about .about-copy {
  margin: 0 0 1.1em;
  max-width: 36em;
  color: var(--mist);
  line-height: 1.85;
}

.page-about .about-inline-link {
  display: inline-block;
  font-size: .92rem;
  text-decoration: none;
  border-bottom: 1px solid var(--cyan-line);
  padding-bottom: 2px;
}

/* ---------- 品牌原则 ---------- */
.page-about .about-principles {
  list-style: none;
  margin: clamp(24px, 4vw, 36px) 0 0;
  padding: 0;
  display: grid;
  gap: 14px;
}

.page-about .about-principle {
  position: relative;
  padding: 22px 22px 24px;
  border-radius: var(--r-lg);
  background:
    radial-gradient(120% 90% at 0% 0%, rgba(0, 229, 208, .12), transparent 62%),
    var(--ink-700);
  border: 1px solid var(--line);
}

.page-about .about-principle:nth-child(2) {
  background:
    radial-gradient(120% 90% at 0% 0%, rgba(255, 106, 43, .14), transparent 62%),
    var(--ink-700);
}

.page-about .about-principle:nth-child(3) {
  background:
    radial-gradient(120% 90% at 0% 0%, rgba(43, 217, 166, .13), transparent 62%),
    var(--ink-700);
  border-radius: var(--r-lg) var(--r-lg) var(--r-lg) var(--r-sm);
}

.page-about .about-principle__title {
  margin: 0 0 8px;
  font-size: 1.02rem;
  font-weight: 700;
  letter-spacing: .02em;
  color: var(--paper);
}

.page-about .about-principle__text {
  margin: 0;
  font-size: .9rem;
  line-height: 1.75;
  color: var(--mist);
}

@media (min-width: 760px) {
  .page-about .about-principles {
    grid-template-columns: repeat(3, minmax(0, 1fr));
  }
}

/* ---------- 历程 ---------- */
.page-about .about-band {
  padding-block: clamp(46px, 8vw, 92px);
}

.page-about .about-band--steel {
  background: var(--ink-800);
  border-block: 1px solid var(--line);
}

.page-about .about-band__head {
  max-width: 44em;
}

.page-about .about-band__head .about-copy {
  margin-bottom: 0;
}

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

.page-about .about-track__figure {
  margin: clamp(24px, 4vw, 36px) 0 clamp(26px, 4vw, 40px);
  max-height: 340px;
  overflow: hidden;
}

.page-about .about-track__figure img {
  max-height: 340px;
}

.page-about .about-timeline {
  list-style: none;
  margin: 0;
  padding: 0 0 12px;
  display: flex;
  gap: 16px;
  overflow-x: auto;
  scroll-snap-type: x mandatory;
  scrollbar-width: thin;
}

.page-about .about-timeline__item {
  position: relative;
  flex: 0 0 min(300px, 84vw);
  scroll-snap-align: start;
  padding-top: 22px;
}

.page-about .about-timeline__item::before {
  content: "";
  position: absolute;
  inset-block-start: 0;
  inset-inline-start: 0;
  width: 9px;
  height: 9px;
  border-radius: 50%;
  background: var(--amber);
  box-shadow: 0 0 0 4px rgba(255, 106, 43, .18);
}

.page-about .about-timeline__item::after {
  content: "";
  position: absolute;
  inset-block-start: 4px;
  inset-inline-start: 15px;
  width: calc(100% - 15px);
  height: 1px;
  background: var(--line-strong);
}

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

.page-about .about-node {
  height: 100%;
  padding: 18px 18px 20px;
  border-radius: var(--r-md);
  background: var(--ink-900);
  border: 1px solid var(--line-strong);
  transition: border-color var(--dur) var(--ease);
}

.page-about .about-node[open] {
  border-color: var(--amber-line);
}

.page-about .about-node__summary {
  list-style: none;
  cursor: pointer;
  display: grid;
  gap: 8px;
}

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

.page-about .about-node__year {
  font-size: 1.28rem;
  letter-spacing: .07em;
  color: var(--amber);
}

.page-about .about-node__title {
  font-size: .98rem;
  font-weight: 700;
  color: var(--paper);
}

.page-about .about-node__hint {
  font-family: var(--font-mono);
  font-size: .7rem;
  letter-spacing: .1em;
  color: var(--steel);
}

.page-about .about-node[open] .about-node__hint {
  color: var(--cyan);
}

.page-about .about-node__text {
  margin: 12px 0 0;
  font-size: .9rem;
  line-height: 1.78;
  color: var(--mist);
}

/* ---------- 规模 ---------- */
.page-about .about-scale {
  display: grid;
  gap: clamp(22px, 4vw, 44px);
}

.page-about .about-scale__stats {
  margin: 0;
  border-top: 1px solid var(--line-strong);
}

.page-about .about-scale__row {
  display: grid;
  gap: 2px;
  padding: 14px 0;
  border-bottom: 1px solid var(--line);
}

.page-about .about-scale__row dt {
  font-size: .8rem;
  letter-spacing: .04em;
  color: var(--steel);
}

.page-about .about-scale__row dd {
  margin: 0;
  font-family: var(--font-mono);
  font-size: clamp(1.5rem, 4.4vw, 2rem);
  letter-spacing: .02em;
  color: var(--cyan);
}

.page-about .about-scale__figure {
  margin: clamp(26px, 4vw, 40px) 0 0;
  border-radius: var(--r-md);
  overflow: hidden;
}

@media (min-width: 560px) {
  .page-about .about-scale__stats {
    display: grid;
    grid-template-columns: repeat(2, minmax(0, 1fr));
    column-gap: 32px;
  }
}

@media (min-width: 920px) {
  .page-about .about-scale {
    grid-template-columns: minmax(0, 1fr) minmax(0, 1.02fr);
    align-items: start;
  }
  .page-about .about-scale__figure {
    margin-top: clamp(26px, 4vw, 40px);
  }
}

/* ---------- 品质 ---------- */
.page-about .about-quality {
  display: grid;
  gap: clamp(22px, 4vw, 40px);
}

.page-about .about-quality__figure {
  margin: 0;
  border-radius: var(--r-md);
  overflow: hidden;
}

.page-about .about-quality__figure img {
  aspect-ratio: 1 / 1;
}

.page-about .about-cert {
  list-style: none;
  margin: clamp(20px, 3vw, 28px) 0 0;
  padding: 0;
  display: grid;
  gap: 14px;
}

.page-about .about-cert__item {
  display: grid;
  gap: 10px;
  padding: 18px 18px 20px;
  border-radius: var(--r-md);
  background: var(--ink-700);
  border: 1px solid var(--line);
}

.page-about .about-cert__item .pill {
  justify-self: start;
}

.page-about .about-cert__title {
  margin: 0 0 6px;
  font-size: .96rem;
  font-weight: 700;
  letter-spacing: .01em;
  color: var(--paper);
}

.page-about .about-cert__text {
  margin: 0;
  font-size: .87rem;
  line-height: 1.72;
  color: var(--mist);
}

@media (min-width: 480px) {
  .page-about .about-cert__item {
    grid-template-columns: auto minmax(0, 1fr);
    gap: 14px;
    align-items: start;
  }
}

@media (min-width: 920px) {
  .page-about .about-quality {
    grid-template-columns: minmax(0, .78fr) minmax(0, 1.22fr);
    align-items: start;
  }
}

/* ---------- 生态 ---------- */
.page-about .about-eco {
  display: grid;
  gap: clamp(22px, 4vw, 44px);
}

.page-about .about-eco__nums {
  list-style: none;
  margin: 0;
  padding: 0;
  display: grid;
  gap: 12px;
}

.page-about .about-eco__num-item {
  display: flex;
  align-items: baseline;
  gap: 12px;
  padding-bottom: 12px;
  border-bottom: 1px dashed var(--line-strong);
}

.page-about .about-eco__num {
  font-size: clamp(2.2rem, 6vw, 3.2rem);
  line-height: 1;
  letter-spacing: .02em;
  color: var(--cyan);
}

.page-about .about-eco__label {
  font-size: .88rem;
  color: var(--mist);
  letter-spacing: .04em;
}

.page-about .about-honor {
  margin: clamp(20px, 3vw, 28px) 0;
  padding: 18px 20px;
  border-inline-start: 3px solid var(--amber);
  border-radius: 0 var(--r-sm) var(--r-sm) 0;
  background: linear-gradient(100deg, rgba(255, 106, 43, .14), transparent 82%);
}

.page-about .about-honor__years {
  margin: 0 0 6px;
  font-size: .82rem;
  letter-spacing: .1em;
  color: var(--amber);
}

.page-about .about-honor__text {
  margin: 0;
  font-size: .96rem;
  color: var(--paper);
  line-height: 1.7;
}

@media (min-width: 920px) {
  .page-about .about-eco {
    grid-template-columns: minmax(0, .58fr) minmax(0, 1.42fr);
    align-items: start;
  }
}

/* ---------- 承诺与下一步 ---------- */
.page-about .about-quote {
  margin: clamp(20px, 3vw, 28px) 0 0;
  padding: clamp(24px, 4vw, 36px);
  background: var(--paper);
  color: var(--ink-900);
  border-radius: var(--r-lg) var(--r-lg) var(--r-lg) var(--r-sm);
}

.page-about .about-quote p {
  margin: 0;
  font-size: clamp(1.05rem, 2.6vw, 1.4rem);
  font-weight: 700;
  line-height: 1.62;
  letter-spacing: .01em;
  max-width: 26em;
}

.page-about .about-next {
  margin-top: clamp(20px, 3vw, 28px);
  display: grid;
  gap: 12px;
}

.page-about .about-next__link {
  display: grid;
  gap: 6px;
  padding: 20px 20px 22px;
  border: 1px solid var(--line-strong);
  border-radius: var(--r-md);
  background: linear-gradient(158deg, rgba(0, 229, 208, .1), transparent 68%);
  text-decoration: none;
  color: var(--paper);
  transition: border-color var(--dur) var(--ease), transform var(--dur) var(--ease), background var(--dur) var(--ease);
}

.page-about .about-next__link:hover,
.page-about .about-next__link:focus-visible {
  border-color: var(--cyan-line);
  transform: translateY(-3px);
  background: linear-gradient(158deg, rgba(0, 229, 208, .18), transparent 70%);
}

.page-about .about-next__label {
  font-size: .72rem;
  letter-spacing: .1em;
  color: var(--cyan);
}

.page-about .about-next__title {
  font-size: 1rem;
  font-weight: 700;
  letter-spacing: .01em;
}

.page-about .about-next__text {
  font-size: .85rem;
  line-height: 1.7;
  color: var(--mist);
}

@media (min-width: 760px) {
  .page-about .about-next {
    grid-template-columns: repeat(3, minmax(0, 1fr));
  }
}

@media (prefers-reduced-motion: reduce) {
  .page-about .about-next__link,
  .page-about .about-index__link,
  .page-about .about-node {
    transition: none;
  }
  .page-about .about-next__link:hover,
  .page-about .about-next__link:focus-visible {
    transform: none;
  }
}