.page-about {
  --about-line: rgba(36, 50, 64, 0.5);
  --about-green-soft: rgba(182, 255, 60, 0.14);
  --about-orange-soft: rgba(255, 122, 26, 0.12);
  --about-cyan-soft: rgba(77, 225, 242, 0.1);
  background: var(--c-base);
  color: var(--c-ink);
  overflow-x: hidden;
}

/* ---------- 首屏 ---------- */
.page-about .about-hero {
  position: relative;
  isolation: isolate;
  padding: clamp(26px, 5vw, 56px) 0 clamp(34px, 6vw, 72px);
  background-color: var(--c-base);
  background-image:
    linear-gradient(var(--about-line) 1px, transparent 1px),
    linear-gradient(90deg, var(--about-line) 1px, transparent 1px);
  background-size: 96px 96px;
  border-bottom: 1px solid var(--c-line);
  overflow: hidden;
}

.page-about .about-hero::before,
.page-about .about-hero::after {
  content: "";
  position: absolute;
  z-index: -1;
  pointer-events: none;
}

.page-about .about-hero::before {
  width: min(440px, 68vw);
  aspect-ratio: 1.15;
  top: -16%;
  right: -10%;
  border-radius: 44% 56% 62% 38% / 54% 42% 58% 46%;
  background: radial-gradient(circle at 42% 40%, var(--about-green-soft), transparent 68%);
}

.page-about .about-hero::after {
  width: min(340px, 58vw);
  aspect-ratio: 1;
  bottom: -26%;
  left: -12%;
  border-radius: 58% 42% 46% 54% / 42% 56% 44% 58%;
  background: radial-gradient(circle at 50% 50%, var(--about-orange-soft), transparent 70%);
}

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

.page-about .about-hero .breadcrumbs {
  margin-bottom: clamp(16px, 3vw, 26px);
  font-size: var(--step--1);
}

.page-about .about-hero .eyebrow {
  margin: 0 0 12px;
}

.page-about .about-hero__title {
  margin: 0 0 18px;
  max-width: 16ch;
  font-family: var(--font-display);
  font-weight: 900;
  letter-spacing: -0.02em;
  line-height: 1.08;
}

.page-about .about-hero__lede {
  max-width: 58ch;
  margin: 0 0 clamp(26px, 4.5vw, 44px);
  font-size: clamp(1rem, 1.9vw, 1.125rem);
}

/* 首屏章节索引 */
.page-about .hero-index {
  display: grid;
  gap: 1px;
  background: var(--c-line);
  border: 1px solid var(--c-line);
  border-radius: var(--r-m);
  overflow: hidden;
}

.page-about .hero-index__item {
  display: flex;
  flex-direction: column;
  gap: 6px;
  padding: 16px 18px;
  background: var(--c-panel);
  text-decoration: none;
  color: var(--c-ink);
  transition: background var(--dur) var(--ease), box-shadow var(--dur) var(--ease);
}

.page-about .hero-index__item:hover,
.page-about .hero-index__item:focus-visible {
  background: var(--c-raised);
  box-shadow: inset 3px 0 0 var(--c-green);
}

.page-about .hero-index__item:focus-visible {
  outline: 2px solid var(--c-cyan);
  outline-offset: -2px;
}

.page-about .hero-index__idx {
  font-size: var(--step--2);
  letter-spacing: 0.14em;
  color: var(--c-green);
}

.page-about .hero-index__label {
  font-family: var(--font-display);
  font-size: 1.0625rem;
  font-weight: 800;
  letter-spacing: -0.01em;
}

.page-about .hero-index__desc {
  font-size: var(--step--1);
  line-height: 1.6;
  color: var(--c-mute);
}

@media (min-width: 700px) {
  .page-about .hero-index {
    grid-template-columns: repeat(3, 1fr);
  }
}

/* ---------- 通用区块 ---------- */
.page-about .about-block {
  position: relative;
  border-bottom: 1px solid var(--c-line);
}

.page-about .about-block__intro {
  max-width: 62ch;
  margin: 0 0 clamp(22px, 3.5vw, 36px);
  color: var(--c-mute);
  font-size: var(--step-0);
}

.page-about .about-block__tail {
  margin: clamp(20px, 3vw, 32px) 0 0;
  max-width: 64ch;
  color: var(--c-mute);
  font-size: var(--step--1);
  line-height: 1.85;
}

.page-about .about-block h2.h-section {
  margin: 8px 0 clamp(16px, 2.6vw, 26px);
  font-family: var(--font-display);
  font-weight: 800;
  letter-spacing: -0.015em;
  line-height: 1.2;
  max-width: 24ch;
}

.page-about .about-block p {
  line-height: 1.85;
}

/* ---------- 图文错位分栏 ---------- */
.page-about .about-split {
  display: grid;
  gap: clamp(22px, 4vw, 46px);
  align-items: start;
}

.page-about .about-split__copy > p {
  margin: 0 0 16px;
  color: var(--c-mute);
}

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

@media (min-width: 900px) {
  .page-about .about-split--7-5 {
    grid-template-columns: 7fr 5fr;
  }

  .page-about .about-split--5-7 {
    grid-template-columns: 5fr 7fr;
  }
}

/* 图框 */
.page-about .shot {
  margin: 0;
  border: 1px solid var(--c-line);
  border-radius: var(--r-l);
  overflow: hidden;
  background: var(--c-panel);
}

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

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

.page-about .shot--tall img {
  aspect-ratio: 14 / 9;
}

.page-about .shot--wide {
  margin: clamp(24px, 4vw, 40px) 0 0;
}

.page-about .shot--wide img {
  aspect-ratio: 3 / 2;
}

.page-about .shot__cap {
  padding: 12px 16px 14px;
  border-top: 1px solid var(--c-line);
  font-size: var(--step--1);
  line-height: 1.6;
  color: var(--c-mute);
}

/* ---------- 资料 / 数据 ---------- */
.page-about .facts {
  display: grid;
  gap: clamp(16px, 2.4vw, 26px);
  margin-bottom: clamp(20px, 3vw, 30px);
}

@media (min-width: 860px) {
  .page-about .facts {
    grid-template-columns: 5fr 7fr;
    align-items: stretch;
  }
}

.page-about .facts__lead {
  position: relative;
  padding: clamp(22px, 3vw, 34px);
  border: 1px solid rgba(182, 255, 60, 0.35);
  border-radius: var(--r-l) var(--r-m) var(--r-l) var(--r-m);
  background:
    radial-gradient(circle at 88% 12%, rgba(182, 255, 60, 0.2), transparent 58%),
    linear-gradient(150deg, rgba(182, 255, 60, 0.1), rgba(77, 225, 242, 0.05));
}

.page-about .facts__big {
  margin: 0;
  font-family: var(--font-mono);
  font-size: clamp(3rem, 9vw, 4.8rem);
  font-weight: 700;
  line-height: 0.95;
  letter-spacing: -0.04em;
  color: var(--c-green);
}

.page-about .facts__biglabel {
  margin: 10px 0 14px;
  font-family: var(--font-display);
  font-size: clamp(1.0625rem, 2vw, 1.25rem);
  font-weight: 800;
  color: var(--c-ink);
}

.page-about .facts__note {
  margin: 0;
  font-size: var(--step--1);
  line-height: 1.75;
  color: var(--c-mute);
}

.page-about .facts__list {
  margin: 0;
  padding: 0;
  list-style: none;
  display: grid;
  gap: 1px;
  background: var(--c-line);
  border: 1px solid var(--c-line);
  border-radius: var(--r-m);
  overflow: hidden;
}

.page-about .facts__row {
  display: grid;
  grid-template-columns: minmax(76px, auto) 1fr;
  align-items: baseline;
  gap: 14px;
  padding: 15px 18px;
  background: var(--c-panel);
  transition: background var(--dur) var(--ease);
}

.page-about .facts__row:hover {
  background: var(--c-raised);
}

.page-about .facts__num {
  font-family: var(--font-mono);
  font-size: clamp(1.25rem, 3vw, 1.6rem);
  font-weight: 700;
  line-height: 1;
  color: var(--c-cyan);
  letter-spacing: -0.02em;
}

.page-about .facts__row:nth-child(3) .facts__num {
  color: var(--c-orange);
}

.page-about .facts__row:nth-child(4) .facts__num {
  color: var(--c-green);
}

.page-about .facts__text {
  font-size: var(--step--1);
  line-height: 1.65;
  color: var(--c-mute);
}

/* ---------- 团队 ---------- */
.page-about .roles {
  display: grid;
  gap: 12px;
}

@media (min-width: 900px) {
  .page-about .roles {
    grid-template-columns: repeat(3, 1fr);
    align-items: start;
  }
}

.page-about .role {
  border: 1px solid var(--c-line);
  border-radius: var(--r-m);
  background: var(--c-panel);
  overflow: hidden;
  transition: border-color var(--dur) var(--ease), background var(--dur) var(--ease);
}

.page-about .role[open] {
  border-color: rgba(182, 255, 60, 0.32);
}

.page-about .role__summary {
  display: grid;
  grid-template-columns: auto 1fr auto;
  align-items: center;
  gap: 12px;
  padding: 16px 18px;
  cursor: pointer;
  list-style: none;
}

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

.page-about .role__summary:focus-visible {
  outline: 2px solid var(--c-cyan);
  outline-offset: -2px;
}

.page-about .role__idx {
  font-family: var(--font-mono);
  font-size: 1.5rem;
  font-weight: 700;
  line-height: 1;
  color: var(--c-green);
  letter-spacing: -0.03em;
}

.page-about .role:nth-child(2) .role__idx {
  color: var(--c-cyan);
}

.page-about .role:nth-child(3) .role__idx {
  color: var(--c-orange);
}

.page-about .role__name {
  font-family: var(--font-display);
  font-size: 1.0625rem;
  font-weight: 800;
  letter-spacing: -0.01em;
}

.page-about .role__mark {
  position: relative;
  width: 14px;
  height: 14px;
  flex: none;
}

.page-about .role__mark::before,
.page-about .role__mark::after {
  content: "";
  position: absolute;
  background: var(--c-mute);
  transition: transform var(--dur) var(--ease), background var(--dur) var(--ease);
}

.page-about .role__mark::before {
  left: 0;
  top: 6px;
  width: 14px;
  height: 2px;
}

.page-about .role__mark::after {
  top: 0;
  left: 6px;
  width: 2px;
  height: 14px;
}

.page-about .role[open] .role__mark::after {
  transform: scaleY(0);
}

.page-about .role[open] .role__mark::before {
  background: var(--c-green);
}

.page-about .role__body {
  padding: 0 18px 18px;
  border-top: 1px solid var(--c-line);
  padding-top: 14px;
}

.page-about .role__body p {
  margin: 0 0 10px;
  font-size: var(--step--1);
  line-height: 1.8;
  color: var(--c-mute);
}

.page-about .role__meta {
  margin: 0;
  font-size: var(--step--2);
  letter-spacing: 0.02em;
}

/* ---------- 历程时间线 ---------- */
.page-about .timeline {
  position: relative;
  margin: 0;
  padding: 0 0 0 38px;
  list-style: none;
}

.page-about .timeline::before {
  content: "";
  position: absolute;
  left: 11px;
  top: 8px;
  bottom: 12px;
  width: 1px;
  background: linear-gradient(180deg, var(--c-green), rgba(77, 225, 242, 0.4) 55%, rgba(182, 255, 60, 0) 100%);
}

.page-about .timeline__item {
  position: relative;
  padding-bottom: clamp(22px, 3.4vw, 34px);
}

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

.page-about .timeline__node {
  position: absolute;
  left: -31px;
  top: 6px;
  width: 15px;
  height: 15px;
  border-radius: 50%;
  border: 2px solid var(--c-green);
  background: var(--c-base);
}

.page-about .timeline__item:first-child .timeline__node {
  background: var(--c-green);
  box-shadow: 0 0 0 5px rgba(182, 255, 60, 0.14);
}

.page-about .timeline__node--orange {
  border-color: var(--c-orange);
}

.page-about .timeline__node--cyan {
  border-color: var(--c-cyan);
}

.page-about .timeline__step {
  margin: 0 0 6px;
  font-size: var(--step--2);
  letter-spacing: 0.14em;
  color: var(--c-mute);
  text-transform: uppercase;
}

.page-about .timeline__title {
  margin: 0 0 8px;
  font-family: var(--font-display);
  font-size: clamp(1.0625rem, 2.2vw, 1.3125rem);
  font-weight: 800;
  letter-spacing: -0.01em;
  line-height: 1.35;
  color: var(--c-ink);
}

.page-about .timeline__text {
  margin: 0;
  max-width: 62ch;
  font-size: var(--step--1);
  line-height: 1.85;
  color: var(--c-mute);
}

/* ---------- 合作 ---------- */
.page-about .about-split--reverse {
  direction: ltr;
}

.page-about .partner-list {
  margin: 0;
  padding: 0;
  list-style: none;
  display: grid;
  gap: 14px;
}

.page-about .partner-list__item {
  padding: 18px 20px;
  border: 1px solid var(--c-line);
  border-radius: var(--r-m);
  background:
    radial-gradient(circle at 100% 0%, rgba(77, 225, 242, 0.07), transparent 60%),
    var(--c-panel);
  transition: border-color var(--dur) var(--ease), transform var(--dur) var(--ease);
}

.page-about .partner-list__item:hover {
  border-color: rgba(77, 225, 242, 0.36);
  transform: translateX(3px);
}

.page-about .partner-list__tag {
  display: inline-block;
  margin-bottom: 10px;
}

.page-about .partner-list__text {
  margin: 0;
  font-size: var(--step--1);
  line-height: 1.85;
  color: var(--c-mute);
}

/* ---------- 承诺 ---------- */
.page-about .pledge {
  margin: 0;
  padding: 0;
  list-style: none;
  display: grid;
  gap: 1px;
  background: var(--c-line);
  border: 1px solid var(--c-line);
  border-radius: var(--r-m);
  overflow: hidden;
}

.page-about .pledge__row {
  display: grid;
  grid-template-columns: 84px 1fr;
  gap: 16px;
  padding: 18px 20px;
  background: var(--c-panel);
  align-items: start;
  transition: background var(--dur) var(--ease);
}

.page-about .pledge__row:hover {
  background: var(--c-raised);
}

.page-about .pledge__key {
  font-size: var(--step--1);
  letter-spacing: 0.12em;
  color: var(--c-green);
  padding-top: 2px;
  border-left: 2px solid var(--c-green);
  padding-left: 10px;
}

.page-about .pledge__row:nth-child(2) .pledge__key {
  color: var(--c-orange);
  border-left-color: var(--c-orange);
}

.page-about .pledge__row:nth-child(3) .pledge__key {
  color: var(--c-cyan);
  border-left-color: var(--c-cyan);
}

.page-about .pledge__row:nth-child(4) .pledge__key {
  color: var(--c-mute);
  border-left-color: var(--c-mute);
}

.page-about .pledge__val {
  font-size: var(--step--1);
  line-height: 1.85;
  color: var(--c-mute);
}

/* ---------- 底部行动区 ---------- */
.page-about .about-cta {
  border-bottom: none;
}

.page-about .about-cta__box {
  display: grid;
  gap: clamp(20px, 3vw, 34px);
  padding: clamp(24px, 4vw, 44px);
  border: 1px solid var(--c-line);
  border-radius: var(--r-l);
  background:
    radial-gradient(circle at 92% 8%, rgba(182, 255, 60, 0.14), transparent 55%),
    radial-gradient(circle at 4% 100%, rgba(255, 122, 26, 0.12), transparent 55%),
    var(--c-panel);
}

@media (min-width: 860px) {
  .page-about .about-cta__box {
    grid-template-columns: 1fr auto;
    align-items: center;
  }
}

.page-about .about-cta__title {
  margin: 8px 0 12px;
  max-width: 22ch;
  font-family: var(--font-display);
  font-weight: 900;
  letter-spacing: -0.02em;
  line-height: 1.15;
}

.page-about .about-cta__text {
  margin: 0;
  max-width: 56ch;
  font-size: var(--step--1);
  line-height: 1.85;
}

.page-about .about-cta__actions {
  display: flex;
  flex-wrap: wrap;
  gap: 12px;
}

.page-about .about-cta__actions .btn {
  white-space: nowrap;
}

/* ---------- 小屏收敛 ---------- */
@media (max-width: 480px) {
  .page-about .about-hero {
    background-size: 64px 64px;
  }

  .page-about .about-hero__title {
    max-width: none;
  }

  .page-about .facts__row {
    grid-template-columns: 1fr;
    gap: 6px;
  }

  .page-about .pledge__row {
    grid-template-columns: 1fr;
    gap: 8px;
  }

  .page-about .pledge__key {
    border-left: none;
    padding-left: 0;
    border-bottom: 2px solid var(--c-green);
    padding-bottom: 6px;
    display: inline-block;
  }

  .page-about .pledge__row:nth-child(2) .pledge__key {
    border-bottom-color: var(--c-orange);
  }

  .page-about .pledge__row:nth-child(3) .pledge__key {
    border-bottom-color: var(--c-cyan);
  }

  .page-about .pledge__row:nth-child(4) .pledge__key {
    border-bottom-color: var(--c-mute);
  }

  .page-about .about-cta__actions .btn {
    flex: 1 1 100%;
    text-align: center;
  }
}

@media (prefers-reduced-motion: reduce) {
  .page-about .hero-index__item,
  .page-about .facts__row,
  .page-about .partner-list__item,
  .page-about .pledge__row,
  .page-about .role,
  .page-about .role__mark::before,
  .page-about .role__mark::after {
    transition: none;
  }

  .page-about .partner-list__item:hover {
    transform: none;
  }
}