.page-about {
  background: var(--char);
  color: var(--white);
  overflow-x: hidden;
}

/* ---------- 首屏 ---------- */
.page-about .about-hero {
  position: relative;
  isolation: isolate;
  padding: clamp(32px, 5vw, 56px) 0 clamp(44px, 6vw, 72px);
  background: var(--green-deep);
  border-bottom: 1px solid var(--line);
  overflow: hidden;
}

.page-about .about-hero__media {
  position: absolute;
  inset: 0;
  z-index: -1;
}

.page-about .about-hero__img {
  display: block;
  width: 100%;
  height: 100%;
  object-fit: cover;
  object-position: center 40%;
  opacity: 0.38;
}

.page-about .about-hero__media::after {
  content: "";
  position: absolute;
  inset: 0;
  background: linear-gradient(180deg, rgba(14, 15, 13, 0.55) 0%, rgba(11, 59, 36, 0.72) 46%, var(--char) 100%);
}

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

.page-about .breadcrumb {
  margin-bottom: clamp(28px, 4vw, 48px);
}

.page-about .breadcrumb__list {
  display: flex;
  flex-wrap: wrap;
  align-items: center;
  gap: 10px;
  margin: 0;
  padding: 0;
  list-style: none;
  font-family: var(--font-mono);
  font-size: 0.6875rem;
  letter-spacing: 0.16em;
  text-transform: uppercase;
  color: var(--gray);
}

.page-about .breadcrumb__item + .breadcrumb__item::before {
  content: "/";
  margin-right: 10px;
  color: var(--line-strong);
}

.page-about .breadcrumb__link {
  color: var(--gray);
  text-decoration: none;
  border-bottom: 1px solid transparent;
}

.page-about .breadcrumb__link:hover,
.page-about .breadcrumb__link:focus-visible {
  color: var(--lime);
  border-bottom-color: var(--lime);
}

.page-about .breadcrumb__current {
  color: var(--white);
}

.page-about .about-hero__eyebrow {
  margin: 0 0 18px;
  font-family: var(--font-mono);
  font-size: 0.6875rem;
  letter-spacing: 0.2em;
  text-transform: uppercase;
  color: var(--lime);
}

.page-about .about-hero__title {
  margin: 0 0 24px;
  max-width: 15ch;
  font-family: var(--font-sans);
  font-size: clamp(2rem, 5.6vw, 4.25rem);
  font-weight: 900;
  line-height: 1.05;
  letter-spacing: -0.02em;
  color: var(--white);
}

.page-about .about-hero__lead {
  max-width: 62ch;
  margin: 0 0 32px;
  font-size: clamp(1rem, 1.15vw, 1.125rem);
  line-height: 1.85;
  color: rgba(242, 245, 239, 0.82);
}

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

/* ---------- 主体骨架 ---------- */
.page-about .about-shell {
  display: grid;
  grid-template-columns: minmax(0, 1fr);
  gap: 32px;
  padding-top: clamp(40px, 6vw, 72px);
  padding-bottom: clamp(48px, 7vw, 88px);
}

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

/* ---------- 左侧轨道 ---------- */
.page-about .about-rail__head {
  margin: 0 0 12px;
  font-family: var(--font-mono);
  font-size: 0.625rem;
  letter-spacing: 0.2em;
  text-transform: uppercase;
  color: var(--gray);
}

.page-about .about-rail__list {
  display: flex;
  gap: 8px;
  margin: 0;
  padding: 0 0 6px;
  list-style: none;
  overflow-x: auto;
  scrollbar-width: none;
  -webkit-overflow-scrolling: touch;
}

.page-about .about-rail__list::-webkit-scrollbar {
  display: none;
}

.page-about .about-rail__item {
  flex: none;
}

.page-about .about-rail__link {
  display: block;
  padding: 10px 14px;
  border: 1px solid var(--line);
  color: var(--gray);
  font-size: 0.8125rem;
  line-height: 1.3;
  text-decoration: none;
  white-space: nowrap;
  transition: color 180ms var(--ease), border-color 180ms var(--ease), background 180ms var(--ease);
}

.page-about .about-rail__link:hover,
.page-about .about-rail__link:focus-visible {
  color: var(--lime);
  border-color: var(--lime-line);
}

/* ---------- 章节通用 ---------- */
.page-about .about-sec {
  position: relative;
  padding-bottom: clamp(44px, 6vw, 76px);
}

.page-about .about-sec + .about-sec {
  margin-top: clamp(44px, 6vw, 76px);
  border-top: 1px solid var(--line);
  padding-top: clamp(40px, 5vw, 64px);
}

.page-about .about-sec + .about-sec::before {
  content: "";
  position: absolute;
  top: -1px;
  left: 0;
  width: min(220px, 55%);
  height: 2px;
  background: linear-gradient(90deg, var(--lime), rgba(200, 255, 61, 0));
}

.page-about .about-sec__head {
  margin-bottom: clamp(24px, 3vw, 36px);
}

.page-about .about-sec__code {
  margin: 0 0 12px;
  font-family: var(--font-mono);
  font-size: 0.6875rem;
  letter-spacing: 0.2em;
  text-transform: uppercase;
  color: var(--lime);
}

.page-about .about-sec__title {
  margin: 0;
  max-width: 24ch;
  font-size: clamp(1.5rem, 3vw, 2.25rem);
  font-weight: 800;
  line-height: 1.22;
  letter-spacing: -0.01em;
  color: var(--white);
}

.page-about .about-sec__lead {
  max-width: 62ch;
  margin: 16px 0 0;
  font-size: 0.9375rem;
  line-height: 1.8;
  color: var(--gray);
}

.page-about .about-prose p {
  max-width: 70ch;
  margin: 0 0 18px;
  font-size: 1rem;
  line-height: 1.85;
  color: rgba(242, 245, 239, 0.8);
}

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

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

.page-about .about-prose a:hover,
.page-about .about-prose a:focus-visible {
  border-bottom-color: var(--lime);
}

/* ---------- 数据锚点 ---------- */
.page-about .about-anchors {
  display: grid;
  grid-template-columns: minmax(0, 1fr);
  gap: 1px;
  margin-top: clamp(28px, 4vw, 40px);
  background: var(--line);
  border: 1px solid var(--line);
}

.page-about .about-anchor {
  background: var(--char);
  padding: 22px 20px 24px;
}

.page-about .about-anchor__num {
  display: block;
  font-family: var(--font-cond);
  font-size: clamp(2.25rem, 5vw, 3.5rem);
  font-weight: 900;
  line-height: 1;
  letter-spacing: -0.01em;
  color: var(--lime);
}

.page-about .about-anchor__unit {
  margin-left: 6px;
  font-family: var(--font-sans);
  font-size: 0.875rem;
  font-weight: 600;
  letter-spacing: 0.02em;
}

.page-about .about-anchor__label {
  display: block;
  margin-top: 12px;
  font-size: 0.8125rem;
  line-height: 1.7;
  color: var(--gray);
}

/* ---------- 版本演进 ---------- */
.page-about .about-roadmap {
  margin: 0;
  padding: 0;
  list-style: none;
  border-top: 1px solid var(--line);
}

.page-about .about-roadmap__item {
  display: grid;
  grid-template-columns: minmax(0, 1fr);
  gap: 10px;
  padding: 26px 0;
  border-bottom: 1px solid var(--line);
}

.page-about .about-roadmap__v {
  font-family: var(--font-cond);
  font-size: clamp(1.875rem, 4vw, 2.75rem);
  font-weight: 900;
  line-height: 0.9;
  letter-spacing: 0.02em;
  color: rgba(200, 255, 61, 0.34);
  transition: color 180ms var(--ease);
}

.page-about .about-roadmap__item:hover .about-roadmap__v {
  color: var(--lime);
}

.page-about .about-roadmap__name {
  margin: 0 0 10px;
  font-size: 1.0625rem;
  font-weight: 700;
  line-height: 1.4;
  color: var(--white);
}

.page-about .about-roadmap__body p {
  max-width: 66ch;
  margin: 0;
  font-size: 0.9375rem;
  line-height: 1.85;
  color: rgba(242, 245, 239, 0.76);
}

/* ---------- 四条内容线 ---------- */
.page-about .about-lines {
  display: grid;
  grid-template-columns: minmax(0, 1fr);
  border-top: 1px solid var(--line);
}

.page-about .about-line {
  display: grid;
  grid-template-columns: minmax(0, 1fr);
  gap: 10px;
  padding: 26px 0;
  border-bottom: 1px solid var(--line);
}

.page-about .about-line__num {
  font-family: var(--font-cond);
  font-size: 1.75rem;
  font-weight: 900;
  line-height: 1;
  letter-spacing: 0.04em;
  color: var(--lime);
}

.page-about .about-line__name {
  margin: 0 0 10px;
  font-size: 1.0625rem;
  font-weight: 700;
  color: var(--white);
}

.page-about .about-line__name::before {
  content: "";
  display: inline-block;
  width: 18px;
  height: 2px;
  margin-right: 10px;
  vertical-align: middle;
  background: var(--lime);
}

.page-about .about-line__desc {
  max-width: 66ch;
  margin: 0 0 10px;
  font-size: 0.9375rem;
  line-height: 1.85;
  color: rgba(242, 245, 239, 0.76);
}

.page-about .about-line__meta {
  margin: 0;
  font-family: var(--font-mono);
  font-size: 0.6875rem;
  letter-spacing: 0.12em;
  text-transform: uppercase;
  color: var(--gray);
}

.page-about .about-line--profile .about-line__num {
  color: rgba(242, 245, 239, 0.7);
}

.page-about .about-line--profile .about-line__name::before {
  background: var(--white);
}

.page-about .about-line--fans .about-line__num {
  color: var(--blue);
}

.page-about .about-line--fans .about-line__name::before {
  background: var(--blue);
}

.page-about .about-line--calendar .about-line__num {
  color: var(--orange);
}

.page-about .about-line--calendar .about-line__name::before {
  background: var(--orange);
}

/* ---------- 图像 ---------- */
.page-about .about-media {
  display: block;
  margin: 0 0 clamp(24px, 3vw, 32px);
  position: relative;
  overflow: hidden;
  border: 1px solid var(--line);
  background: var(--graphite);
}

.page-about .about-media--16x9 {
  aspect-ratio: 16 / 9;
}

.page-about .about-media--blue {
  border-color: rgba(30, 111, 217, 0.45);
  margin-top: clamp(24px, 3vw, 32px);
  margin-bottom: 0;
}

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

/* ---------- 团队 ---------- */
.page-about .about-team__stats {
  display: flex;
  flex-wrap: wrap;
  gap: 20px 40px;
  margin-top: clamp(24px, 3vw, 32px);
  padding-top: clamp(20px, 3vw, 28px);
  border-top: 1px solid var(--line);
}

.page-about .about-team__stat {
  display: flex;
  align-items: baseline;
  gap: 8px;
}

.page-about .about-team__num {
  font-family: var(--font-cond);
  font-size: 1.875rem;
  font-weight: 900;
  line-height: 1;
  color: var(--lime);
}

.page-about .about-team__cap {
  font-size: 0.8125rem;
  line-height: 1.5;
  color: var(--gray);
}

/* ---------- 上海球迷分会 ---------- */
.page-about .about-fans {
  position: relative;
  padding: clamp(22px, 3vw, 32px) clamp(18px, 2.4vw, 28px);
  background: linear-gradient(150deg, rgba(30, 111, 217, 0.18) 0%, rgba(14, 15, 13, 0) 68%);
  border-left: 2px solid var(--blue);
}

.page-about .about-fans p {
  max-width: 68ch;
  margin: 0 0 16px;
  font-size: 0.9375rem;
  line-height: 1.85;
  color: rgba(242, 245, 239, 0.82);
}

.page-about .about-fans__lead {
  font-size: 1rem !important;
  font-weight: 600;
  color: var(--white) !important;
}

.page-about .about-fans__facts {
  display: grid;
  grid-template-columns: minmax(0, 1fr);
  gap: 1px;
  margin: 22px 0 0;
  padding: 0;
  list-style: none;
  background: rgba(30, 111, 217, 0.28);
  border: 1px solid rgba(30, 111, 217, 0.28);
}

.page-about .about-fans__facts li {
  background: var(--char);
  padding: 14px 16px;
  font-size: 0.8125rem;
  line-height: 1.6;
  color: var(--gray);
}

.page-about .about-fans__facts li span {
  display: block;
  font-family: var(--font-cond);
  font-size: 1.5rem;
  font-weight: 900;
  line-height: 1.1;
  color: var(--blue);
}

/* ---------- 分段控件与步骤 ---------- */
.page-about .about-steps {
  margin-top: clamp(26px, 3vw, 34px);
}

.page-about .about-steps .segmented {
  display: flex;
  flex-wrap: wrap;
  gap: 1px;
  width: fit-content;
  max-width: 100%;
  margin-bottom: 16px;
  background: rgba(30, 111, 217, 0.34);
  border: 1px solid rgba(30, 111, 217, 0.34);
}

.page-about .about-steps .segmented__btn {
  appearance: none;
  min-height: 44px;
  padding: 10px 16px;
  border: 0;
  background: var(--char);
  color: var(--gray);
  font-family: var(--font-sans);
  font-size: 0.8125rem;
  font-weight: 600;
  cursor: pointer;
  transition: background 180ms var(--ease), color 180ms var(--ease);
}

.page-about .about-steps .segmented__btn:hover {
  color: var(--white);
}

.page-about .about-steps .segmented__btn[aria-selected="true"] {
  background: var(--lime);
  color: var(--char);
}

.page-about .about-steps .segmented__btn:focus-visible {
  outline: 2px solid var(--lime);
  outline-offset: 2px;
}

.page-about .about-step {
  border: 1px solid rgba(30, 111, 217, 0.34);
  background: rgba(30, 111, 217, 0.07);
  padding: 20px 20px 22px;
}

.page-about .about-step + .about-step {
  margin-top: 8px;
}

.page-about .about-step h3 {
  margin: 0 0 8px;
  font-size: 1rem;
  font-weight: 700;
  color: var(--white);
}

.page-about .about-step p {
  margin: 0;
  max-width: 62ch;
  font-size: 0.875rem;
  line-height: 1.8;
  color: rgba(242, 245, 239, 0.76);
}

/* ---------- 合作与授权 ---------- */
.page-about .about-partners {
  display: grid;
  grid-template-columns: minmax(0, 1fr);
  gap: 1px;
  margin-top: clamp(26px, 3vw, 34px);
  background: var(--line);
  border: 1px solid var(--line);
}

.page-about .about-partners__item {
  background: var(--char);
  padding: 24px 20px 26px;
}

.page-about .about-partners__num {
  display: block;
  font-family: var(--font-cond);
  font-size: 3rem;
  font-weight: 900;
  line-height: 1;
  color: var(--lime);
}

.page-about .about-partners__label {
  display: block;
  margin: 8px 0 12px;
  font-size: 0.875rem;
  font-weight: 700;
  letter-spacing: 0.04em;
  color: var(--white);
}

.page-about .about-partners__item p {
  margin: 0;
  font-size: 0.8125rem;
  line-height: 1.75;
  color: var(--gray);
}

/* ---------- 下一步 ---------- */
.page-about .about-next {
  margin: 0;
  padding: 0;
  list-style: none;
  display: grid;
  grid-template-columns: minmax(0, 1fr);
  gap: 1px;
  background: var(--line);
  border-block: 1px solid var(--line);
}

.page-about .about-next__item {
  display: grid;
  grid-template-columns: 44px minmax(0, 1fr);
  gap: 16px;
  align-items: start;
  padding: 24px 0;
  background: var(--char);
}

.page-about .about-next__idx {
  font-family: var(--font-cond);
  font-size: 1.5rem;
  font-weight: 900;
  line-height: 1.1;
  letter-spacing: 0.06em;
  color: var(--lime);
}

.page-about .about-next__item h3 {
  margin: 0 0 8px;
  font-size: 1rem;
  font-weight: 700;
  color: var(--white);
}

.page-about .about-next__item p {
  margin: 0;
  max-width: 62ch;
  font-size: 0.875rem;
  line-height: 1.8;
  color: rgba(242, 245, 239, 0.76);
}

/* ---------- 收尾行动区 ---------- */
.page-about .about-cta-wrap {
  padding-bottom: clamp(48px, 7vw, 88px);
}

.page-about .about-cta {
  position: relative;
  overflow: hidden;
  padding: clamp(32px, 4.5vw, 52px) clamp(22px, 3.6vw, 44px);
  background: var(--green-deep);
  border: 1px solid var(--lime-line);
}

.page-about .about-cta::after {
  content: "";
  position: absolute;
  right: -70px;
  bottom: -90px;
  width: 240px;
  height: 240px;
  border: 1px solid var(--lime-line);
  transform: rotate(45deg);
  pointer-events: none;
}

.page-about .about-cta__title {
  margin: 0 0 14px;
  max-width: 22ch;
  font-size: clamp(1.375rem, 2.6vw, 2rem);
  font-weight: 800;
  line-height: 1.24;
  color: var(--white);
}

.page-about .about-cta__text {
  max-width: 62ch;
  margin: 0 0 26px;
  font-size: 0.9375rem;
  line-height: 1.85;
  color: rgba(242, 245, 239, 0.8);
}

.page-about .about-cta__acts {
  display: flex;
  flex-wrap: wrap;
  gap: 12px;
  margin-bottom: 22px;
}

.page-about .about-cta__note {
  margin: 0;
  font-size: 0.8125rem;
  line-height: 1.8;
  color: var(--gray);
}

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

.page-about .about-cta__note a:hover,
.page-about .about-cta__note a:focus-visible {
  border-bottom-color: var(--lime);
}

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

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

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

@media (min-width: 768px) {
  .page-about .about-roadmap__item {
    grid-template-columns: 96px minmax(0, 1fr);
    gap: 28px;
    padding: 30px 0;
  }

  .page-about .about-line {
    grid-template-columns: 88px minmax(0, 1fr);
    gap: 28px;
    padding: 30px 0;
  }

  .page-about .about-line:nth-child(even) {
    padding-left: 48px;
  }

  .page-about .about-fans__facts {
    grid-template-columns: repeat(4, minmax(0, 1fr));
  }
}

@media (min-width: 900px) {
  .page-about .about-shell {
    grid-template-columns: 168px minmax(0, 1fr);
    gap: 56px;
  }

  .page-about .about-rail {
    position: sticky;
    top: 104px;
    align-self: start;
  }

  .page-about .about-rail__item {
    flex: initial;
  }

  .page-about .about-rail__list {
    display: block;
    position: relative;
    padding: 0 0 0 22px;
    overflow: visible;
  }

  .page-about .about-rail__list::before {
    content: "";
    position: absolute;
    left: 4px;
    top: 10px;
    bottom: 10px;
    width: 1px;
    background: var(--line-strong);
  }

  .page-about .about-rail__link {
    position: relative;
    border: 0;
    padding: 10px 0;
    white-space: normal;
    line-height: 1.5;
    font-size: 0.875rem;
  }

  .page-about .about-rail__link::before {
    content: "";
    position: absolute;
    left: -22px;
    top: 15px;
    width: 9px;
    height: 9px;
    background: var(--graphite);
    border: 1px solid var(--line-strong);
    transition: background 180ms var(--ease), border-color 180ms var(--ease);
  }

  .page-about .about-rail__link:hover::before,
  .page-about .about-rail__link:focus-visible::before {
    background: var(--lime);
    border-color: var(--lime);
  }
}

@media (min-width: 1200px) {
  .page-about .about-shell {
    grid-template-columns: 196px minmax(0, 1fr);
    gap: 76px;
  }
}

@media (prefers-reduced-motion: reduce) {
  .page-about .about-rail__link,
  .page-about .about-roadmap__v,
  .page-about .about-steps .segmented__btn {
    transition: none;
  }
}