.page-about {
  background: var(--bg);
  color: var(--fg);
  font-family: var(--ff-body);
  font-size: var(--fs-body);
  line-height: 1.75;
}

/* ---------- 首屏 ---------- */
.page-about .about-hero {
  position: relative;
  overflow: hidden;
  padding: calc(var(--header-h) + clamp(36px, 5vw, 68px)) 0 clamp(36px, 5vw, 60px);
  border-bottom: 2px solid var(--line-strong);
  background-color: var(--ice-abyss);
  background-image:
    radial-gradient(circle at 78% 12%, rgba(30, 90, 125, 0.55), transparent 58%),
    linear-gradient(to right, rgba(127, 212, 240, 0.07) 1px, transparent 1px),
    linear-gradient(to bottom, rgba(127, 212, 240, 0.07) 1px, transparent 1px);
  background-size: auto, 64px 64px, 64px 64px;
}

.page-about .about-hero__grid {
  display: grid;
  grid-template-columns: 1fr;
  gap: clamp(28px, 4vw, 48px);
  align-items: start;
}

.page-about .about-kicker {
  display: flex;
  align-items: center;
  gap: 10px;
  margin: 0 0 18px;
  color: var(--ice-light);
  font-size: 0.76rem;
}
.page-about .about-kicker::before {
  content: "";
  width: 28px;
  height: 2px;
  background: var(--neon);
}

.page-about .about-hero h1 {
  margin: 0 0 22px;
  font-family: var(--ff-display);
  font-size: var(--fs-h1);
  font-weight: 900;
  line-height: 1.03;
  letter-spacing: -0.02em;
  color: var(--ice-white);
}

.page-about .about-hero__lede {
  margin: 0 0 1.1em;
  max-width: 56ch;
  color: var(--ice-pale);
  font-size: var(--fs-body);
  line-height: 1.8;
}
.page-about .about-hero__lede:last-of-type {
  margin-bottom: 0;
}

.page-about .about-hero__actions {
  display: flex;
  flex-wrap: wrap;
  gap: 12px;
  margin-top: 28px;
}

.page-about .about-preview {
  border: 2px solid var(--line-strong);
  background: rgba(11, 34, 55, 0.86);
  box-shadow: var(--shadow-hard);
  padding: 18px 18px 6px;
}

.page-about .about-preview__title {
  margin: 0;
  color: var(--steel);
  font-size: 0.72rem;
}

.page-about .about-preview ol {
  list-style: none;
  margin: 12px 0 0;
  padding: 0;
}

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

.page-about .about-preview a {
  display: grid;
  grid-template-columns: 30px minmax(0, 1fr);
  gap: 10px;
  padding: 11px 0;
  color: var(--ice-white);
  text-decoration: none;
  font-weight: 700;
  font-size: 0.94rem;
  transition: color var(--dur) linear;
}
.page-about .about-preview a .num {
  color: var(--neon);
  font-size: 0.82rem;
  font-weight: 500;
  padding-top: 2px;
}
.page-about .about-preview a em {
  display: block;
  margin-top: 3px;
  font-style: normal;
  font-weight: 400;
  font-size: 0.8rem;
  line-height: 1.55;
  color: var(--steel);
}
.page-about .about-preview a:hover,
.page-about .about-preview a:focus-visible {
  color: var(--neon);
}

/* ---------- 数据条 ---------- */
.page-about .about-statline {
  background: var(--ice-deep);
  border-bottom: 2px solid var(--line-strong);
}

.page-about .about-statline__grid {
  display: grid;
  grid-template-columns: repeat(2, minmax(0, 1fr));
  gap: 1px;
  background: var(--line);
}

.page-about .about-stat {
  background: var(--ice-deep);
  padding: 18px 14px;
}

.page-about .about-stat__num {
  display: block;
  font-family: var(--ff-mono);
  font-size: clamp(1.4rem, 3vw, 2rem);
  font-weight: 700;
  line-height: 1;
  color: var(--neon);
  letter-spacing: 0.01em;
}

.page-about .about-stat__label {
  display: block;
  margin-top: 9px;
  font-size: 0.78rem;
  line-height: 1.5;
  color: var(--steel);
  letter-spacing: 0.03em;
}

/* ---------- 主体两栏 ---------- */
.page-about .about-shell {
  display: grid;
  grid-template-columns: minmax(0, 1fr);
  gap: 0;
  padding-top: clamp(28px, 4vw, 52px);
  padding-bottom: clamp(48px, 6vw, 84px);
}

.page-about .about-rail {
  display: flex;
  gap: 6px;
  overflow-x: auto;
  padding-bottom: 10px;
  margin-bottom: 22px;
  border-bottom: 1px solid var(--line);
  -webkit-overflow-scrolling: touch;
}

.page-about .about-rail__link {
  flex: 0 0 auto;
  display: inline-flex;
  align-items: baseline;
  gap: 7px;
  padding: 7px 11px;
  border: 1px solid var(--line);
  color: var(--steel);
  text-decoration: none;
  font-size: 0.8rem;
  white-space: nowrap;
  transition: color var(--dur) linear, border-color var(--dur) linear;
}
.page-about .about-rail__link .num {
  font-size: 0.72rem;
  color: var(--ice-bright);
}
.page-about .about-rail__link:hover,
.page-about .about-rail__link:focus-visible {
  color: var(--ice-white);
  border-color: var(--line-strong);
}
.page-about .about-rail__link[aria-current="true"] {
  color: var(--neon);
  border-color: var(--neon);
  background: rgba(182, 255, 60, 0.07);
}
.page-about .about-rail__link[aria-current="true"] .num {
  color: var(--neon);
}

/* ---------- 章节骨架 ---------- */
.page-about .about-section {
  border-top: 1px solid var(--line);
  padding: clamp(26px, 4vw, 48px) 0;
}
.page-about .about-section:first-child {
  border-top: 0;
  padding-top: 0;
}

.page-about .about-section__head {
  display: grid;
  grid-template-columns: minmax(0, 1fr);
  gap: 8px;
  margin-bottom: 20px;
}

.page-about .about-no {
  font-family: var(--ff-mono);
  font-size: 0.95rem;
  letter-spacing: 0.16em;
  color: var(--ice-bright);
}

.page-about .about-section h2 {
  margin: 0;
  font-family: var(--ff-display);
  font-size: var(--fs-h2);
  font-weight: 900;
  line-height: 1.14;
  letter-spacing: -0.015em;
  color: var(--ice-white);
}

.page-about .about-section__body p {
  max-width: 68ch;
  margin: 0 0 1.15em;
  color: var(--ice-pale);
}

.page-about .about-section__body h3 {
  margin: 0 0 8px;
  font-size: var(--fs-h3);
  font-weight: 800;
  line-height: 1.3;
  color: var(--ice-white);
}

/* ---------- 三条准则 ---------- */
.page-about .about-codes {
  display: grid;
  grid-template-columns: minmax(0, 1fr);
  gap: 1px;
  margin-top: 26px;
  background: var(--line);
  border: 2px solid var(--line-strong);
}

.page-about .about-code {
  background: var(--ice-deep);
  padding: 20px 18px;
}

.page-about .about-code__k {
  font-family: var(--ff-mono);
  font-size: 0.72rem;
  letter-spacing: 0.16em;
  color: var(--neon);
}

.page-about .about-code p {
  margin: 0;
  font-size: 0.93rem;
  line-height: 1.72;
  color: var(--ice-pale);
}

.page-about .about-code__time {
  display: block;
  margin-top: 16px;
  padding-top: 12px;
  border-top: 1px solid var(--line);
  font-family: var(--ff-mono);
  font-size: 0.76rem;
  line-height: 1.6;
  letter-spacing: 0.02em;
  color: var(--orange);
}

/* ---------- 反色区块 ---------- */
.page-about .about-section.about-halt {
  position: relative;
  overflow: hidden;
  margin: 10px 0;
  padding: clamp(30px, 4.5vw, 56px) clamp(16px, 3vw, 34px);
  border-top: 2px solid var(--line-strong);
  border-bottom: 2px solid var(--line-strong);
  background: var(--ice-deep);
}

.page-about .about-halt__bg {
  position: absolute;
  inset: 0;
  width: 100%;
  height: 100%;
  object-fit: cover;
  opacity: 0.16;
  pointer-events: none;
}

.page-about .about-halt .about-section__head,
.page-about .about-halt .about-section__body {
  position: relative;
  z-index: 1;
}

/* ---------- 流水线 ---------- */
.page-about .about-flow {
  display: grid;
  grid-template-columns: minmax(0, 1fr);
  gap: 12px;
  margin-top: 24px;
}

.page-about .about-step {
  border: 2px solid var(--line-strong);
  background: rgba(6, 18, 31, 0.82);
  transition: border-color var(--dur) linear;
}
.page-about .about-step[open] {
  border-color: var(--neon);
  box-shadow: var(--shadow-neon);
}

.page-about .about-step summary {
  display: block;
  padding: 14px 14px 12px;
  cursor: pointer;
  list-style: none;
}
.page-about .about-step summary::-webkit-details-marker {
  display: none;
}

.page-about .about-step__time {
  display: block;
  font-family: var(--ff-mono);
  font-size: 0.76rem;
  letter-spacing: 0.06em;
  color: var(--orange);
}

.page-about .about-step__title {
  display: block;
  margin-top: 7px;
  font-weight: 800;
  font-size: 0.97rem;
  line-height: 1.4;
  color: var(--ice-white);
}

.page-about .about-step__body {
  padding: 0 14px 15px;
}
.page-about .about-step__body p {
  margin: 0;
  padding-top: 12px;
  border-top: 1px solid var(--line);
  max-width: none;
  font-size: 0.88rem;
  line-height: 1.72;
  color: var(--ice-pale);
}

/* ---------- 团队 ---------- */
.page-about .about-team {
  display: grid;
  grid-template-columns: minmax(0, 1fr);
  gap: 22px;
  margin-top: 24px;
}

.page-about .about-team__item {
  border-left: 2px solid var(--ice-bright);
  padding-left: 16px;
}

.page-about .about-team__num {
  display: block;
  font-family: var(--ff-mono);
  font-size: clamp(1.5rem, 3vw, 2.1rem);
  font-weight: 700;
  line-height: 1;
  color: var(--ice-light);
  margin-bottom: 8px;
}

.page-about .about-team__item p {
  margin: 0;
  font-size: 0.93rem;
  line-height: 1.72;
  color: var(--ice-pale);
}

.page-about .about-note {
  margin-top: 26px;
  padding: 16px 18px;
  border: 1px dashed var(--line-strong);
  background: rgba(18, 58, 87, 0.34);
  font-size: 0.9rem;
  line-height: 1.75;
  color: var(--ice-pale);
  max-width: none;
}

/* ---------- 版本时间轴 ---------- */
.page-about .about-version-img {
  display: block;
  width: 100%;
  height: auto;
  margin-bottom: 26px;
  border: 2px solid var(--line-strong);
}

.page-about .about-timeline {
  position: relative;
  margin-top: 26px;
  padding-left: 26px;
}
.page-about .about-timeline::before {
  content: "";
  position: absolute;
  left: 5px;
  top: 8px;
  bottom: 8px;
  width: 2px;
  background: linear-gradient(to bottom, var(--neon), var(--ice-bright) 42%, var(--line));
}

.page-about .about-vnode {
  position: relative;
  padding-bottom: 24px;
}
.page-about .about-vnode:last-child {
  padding-bottom: 0;
}
.page-about .about-vnode::before {
  content: "";
  position: absolute;
  left: -26px;
  top: 7px;
  width: 12px;
  height: 12px;
  border: 2px solid var(--neon);
  border-radius: var(--radius);
  background: var(--ice-deep);
}
.page-about .about-vnode:hover::before {
  background: var(--neon);
}

.page-about .about-vnode__ver {
  display: block;
  font-family: var(--ff-mono);
  font-size: 0.8rem;
  letter-spacing: 0.08em;
  color: var(--neon);
}

.page-about .about-vnode h3 {
  margin: 5px 0 7px;
  font-size: 1.05rem;
  font-weight: 800;
  color: var(--ice-white);
}

.page-about .about-vnode p {
  margin: 0;
  max-width: 62ch;
  font-size: 0.93rem;
  line-height: 1.75;
  color: var(--ice-pale);
}

/* ---------- 覆盖与合作 ---------- */
.page-about .about-cover {
  display: grid;
  grid-template-columns: minmax(0, 1fr);
  gap: 26px;
  align-items: start;
}

.page-about .about-leagues {
  display: flex;
  flex-wrap: wrap;
  gap: 8px;
  list-style: none;
  margin: 20px 0 22px;
  padding: 0;
}
.page-about .about-leagues li {
  padding: 6px 12px;
  border: 1px solid var(--line-strong);
  font-family: var(--ff-mono);
  font-size: 0.78rem;
  letter-spacing: 0.02em;
  color: var(--ice-light);
}

.page-about .about-cover__figure {
  margin: 0;
}
.page-about .about-cover__figure img {
  display: block;
  width: 100%;
  height: auto;
  border: 2px solid var(--line-strong);
  box-shadow: var(--shadow-hard);
}
.page-about .about-cover__caption {
  display: block;
  margin-top: 10px;
  font-size: 0.72rem;
  color: var(--steel);
}

/* ---------- 纠错 ---------- */
.page-about .about-fix {
  display: grid;
  grid-template-columns: minmax(0, 1fr);
  gap: 14px;
  margin-top: 22px;
}

.page-about .about-fix__item {
  border: 2px solid var(--line-strong);
  background: var(--ice-deep);
  padding: 18px 16px;
}
.page-about .about-fix__item:hover {
  border-color: var(--orange);
}
.page-about .about-fix__item h3 {
  margin: 0 0 8px;
  font-size: 1rem;
  font-weight: 800;
  color: var(--ice-white);
}
.page-about .about-fix__item p {
  margin: 0;
  max-width: none;
  font-size: 0.9rem;
  line-height: 1.72;
  color: var(--ice-pale);
}

/* ---------- 结尾引导 ---------- */
.page-about .about-cta {
  display: grid;
  grid-template-columns: minmax(0, 1fr);
  gap: 22px;
  margin-top: clamp(28px, 4vw, 52px);
  padding: clamp(22px, 3.5vw, 38px);
  border: 2px solid var(--neon);
  background:
    linear-gradient(135deg, rgba(182, 255, 60, 0.12), transparent 62%),
    var(--ice-deep);
}

.page-about .about-cta h2 {
  margin: 0 0 10px;
  font-family: var(--ff-display);
  font-size: var(--fs-h3);
  font-weight: 900;
  line-height: 1.25;
  color: var(--ice-white);
}
.page-about .about-cta p {
  margin: 0;
  max-width: 52ch;
  font-size: 0.93rem;
  line-height: 1.75;
  color: var(--ice-pale);
}

.page-about .about-cta__links {
  display: flex;
  flex-wrap: wrap;
  gap: 10px;
  align-content: start;
}

/* ---------- 响应式 ---------- */
@media (min-width: 640px) {
  .page-about .about-statline__grid {
    grid-template-columns: repeat(4, minmax(0, 1fr));
  }
  .page-about .about-flow {
    grid-template-columns: repeat(2, minmax(0, 1fr));
  }
  .page-about .about-fix {
    grid-template-columns: repeat(2, minmax(0, 1fr));
  }
}

@media (min-width: 900px) {
  .page-about .about-hero__grid {
    grid-template-columns: minmax(0, 1.15fr) minmax(0, 0.85fr);
    gap: clamp(32px, 4vw, 56px);
  }
  .page-about .about-section__head {
    grid-template-columns: 62px minmax(0, 1fr);
    gap: 0 20px;
    align-items: start;
  }
  .page-about .about-codes {
    grid-template-columns: repeat(3, minmax(0, 1fr));
  }
  .page-about .about-team {
    grid-template-columns: repeat(3, minmax(0, 1fr));
    gap: 20px;
  }
  .page-about .about-cover {
    grid-template-columns: minmax(0, 1fr) minmax(0, 0.85fr);
    gap: 34px;
  }
  .page-about .about-cta {
    grid-template-columns: minmax(0, 1fr) auto;
    align-items: center;
  }
}

@media (min-width: 1024px) {
  .page-about .about-shell {
    grid-template-columns: 118px minmax(0, 1fr);
    gap: clamp(26px, 3.5vw, 54px);
  }
  .page-about .about-rail {
    position: sticky;
    top: calc(var(--header-h-compact) + 26px);
    align-self: start;
    flex-direction: column;
    gap: 2px;
    overflow: visible;
    margin-bottom: 0;
    padding-bottom: 0;
    border-bottom: 0;
  }
  .page-about .about-rail__link {
    border: 0;
    border-left: 2px solid transparent;
    padding: 8px 10px;
    font-size: 0.82rem;
  }
  .page-about .about-rail__link[aria-current="true"] {
    border-left-color: var(--neon);
    background: rgba(182, 255, 60, 0.07);
  }
  .page-about .about-flow {
    grid-template-columns: repeat(4, minmax(0, 1fr));
  }
}

@media (prefers-reduced-motion: reduce) {
  .page-about .about-preview a,
  .page-about .about-step,
  .page-about .about-rail__link {
    transition: none;
  }
}