.page-about {
  --about-rail: 208px;
  --about-soft: #4C5D55;
  --about-on-dark: #C3D2CA;
  background: var(--paper);
  color: var(--ink);
}

/* ---------- 首屏 ---------- */
.page-about .about-hero {
  position: relative;
  overflow: hidden;
  background:
    radial-gradient(1100px 460px at 84% -12%, rgba(43, 232, 176, 0.16), transparent 62%),
    linear-gradient(160deg, var(--pitch-800), var(--pitch-900));
  color: var(--white);
  padding: 30px 0 46px;
}
.page-about .about-hero::after {
  content: "";
  position: absolute;
  left: 0;
  right: 0;
  bottom: 0;
  height: 3px;
  background: linear-gradient(90deg, var(--red) 0 9%, var(--yellow) 9% 17%, var(--teal) 17% 33%, rgba(43, 232, 176, 0) 33%);
  opacity: 0.85;
}
.page-about .about-crumbs {
  margin-bottom: 22px;
}
.page-about .about-crumbs .breadcrumbs__item,
.page-about .about-crumbs .breadcrumbs__sep {
  color: rgba(255, 255, 255, 0.6);
}
.page-about .about-crumbs a {
  color: var(--teal);
  text-decoration: none;
}
.page-about .about-hero__grid {
  display: grid;
  grid-template-columns: minmax(0, 1fr);
  gap: 26px;
}
.page-about .about-eyebrow {
  color: var(--teal);
  margin: 0 0 12px;
}
.page-about .about-hero h1 {
  font-family: var(--font-display);
  font-size: clamp(30px, 6.2vw, 54px);
  line-height: 1.04;
  letter-spacing: -0.02em;
  font-weight: 800;
  margin: 0 0 16px;
  max-width: 15ch;
}
.page-about .about-hero__lede {
  font-size: 16px;
  line-height: 1.78;
  color: var(--about-on-dark);
  margin: 0;
  max-width: 46ch;
}
.page-about .about-hero__facts {
  list-style: none;
  margin: 26px 0 0;
  padding: 0;
  display: flex;
  flex-wrap: wrap;
  gap: 10px 26px;
}
.page-about .about-hero__facts li {
  display: flex;
  align-items: baseline;
  gap: 7px;
  font-size: 13px;
  color: var(--about-on-dark);
}
.page-about .about-hero__facts .num {
  font-size: 22px;
  font-weight: 600;
  color: var(--teal);
}
.page-about .about-hero__media {
  border: 1px solid var(--pitch-600);
  border-radius: var(--radius-organic);
  overflow: hidden;
  margin: 0;
}
.page-about .media img {
  display: block;
  width: 100%;
  height: 100%;
  object-fit: cover;
  max-width: 100%;
}
.page-about .about-hero__media .media__caption {
  color: rgba(255, 255, 255, 0.72);
}

/* ---------- 左轨 + 主体 ---------- */
.page-about .about-shell {
  display: grid;
  grid-template-columns: minmax(0, 1fr);
  gap: 0;
  padding-top: 8px;
  padding-bottom: 64px;
}
.page-about .about-body {
  min-width: 0;
}
.page-about .about-rail {
  display: none;
}
.page-about .about-sec {
  padding: 30px 0 36px;
  border-top: 1px dotted var(--line);
}
.page-about .about-sec:first-child {
  border-top: 0;
  padding-top: 18px;
}

/* ---------- 章节头 ---------- */
.page-about .sec-head {
  display: flex;
  align-items: baseline;
  gap: 12px;
  padding-bottom: 12px;
  margin-bottom: 18px;
  border-bottom: 1px solid var(--line);
}
.page-about .sec-head__no {
  font-size: 12px;
  letter-spacing: 0.1em;
  color: var(--teal-ink);
  flex: none;
}
.page-about .sec-head__title {
  font-family: var(--font-display);
  font-size: clamp(21px, 3.4vw, 31px);
  line-height: 1.16;
  letter-spacing: -0.01em;
  font-weight: 800;
  margin: 0;
  color: var(--ink);
}

/* ---------- 正文 ---------- */
.page-about .sec-text p {
  font-size: 16px;
  line-height: 1.8;
  color: var(--about-soft);
  margin: 0 0 14px;
  max-width: 66ch;
}
.page-about .sec-text p:last-child {
  margin-bottom: 0;
}
.page-about .sec-text--dark p {
  color: var(--about-on-dark);
}
.page-about .sec-foot {
  margin: 18px 0 0;
  font-size: 14px;
  line-height: 1.75;
  color: var(--moss-ink);
  max-width: 66ch;
}
.page-about .sec-note {
  margin-top: 20px;
  padding: 18px 18px 18px 20px;
  background: var(--white);
  border: 1px solid var(--line);
  border-left: 3px solid var(--teal-ink);
  border-radius: 2px 14px 2px 14px;
}
.page-about .sec-note__k {
  margin: 0 0 8px;
  font-size: 11px;
  letter-spacing: 0.12em;
  text-transform: uppercase;
  color: var(--teal-ink);
}
.page-about .sec-note__v {
  margin: 0;
  font-size: 15px;
  line-height: 1.7;
  color: var(--ink);
  font-weight: 600;
}
.page-about .about-link {
  display: inline-block;
  margin-top: 14px;
  font-size: 15px;
  font-weight: 600;
  color: var(--teal-ink);
  text-decoration: none;
  border-bottom: 1px solid currentColor;
  padding-bottom: 2px;
}
.page-about .about-link:hover,
.page-about .about-link:focus-visible {
  color: var(--pitch-800);
}
.page-about .sec-foot .about-link {
  margin-top: 0;
  margin-left: 4px;
}

/* ---------- 深色章节 ---------- */
.page-about .about-sec--dark {
  position: relative;
  overflow: hidden;
  margin: 16px 0;
  padding: 28px 20px 32px;
  border: 0;
  background: linear-gradient(158deg, var(--pitch-800), var(--pitch-900));
  color: var(--white);
  border-radius: var(--radius-organic);
}
.page-about .about-sec--deep {
  background: linear-gradient(158deg, var(--pitch-900), var(--pitch-800) 78%);
}
.page-about .about-sec--dark .sec-head {
  border-bottom-color: rgba(255, 255, 255, 0.16);
}
.page-about .about-sec--dark .sec-head__no {
  color: var(--teal);
}
.page-about .about-sec--dark .sec-head__title {
  color: var(--white);
}
.page-about .ver__ghost {
  position: absolute;
  right: -4px;
  top: -16px;
  font-size: 120px;
  line-height: 1;
  font-weight: 700;
  letter-spacing: -0.05em;
  color: var(--white);
  opacity: 0.06;
  pointer-events: none;
}

/* ---------- 版本切换 ---------- */
.page-about .ver {
  position: relative;
  margin-top: 18px;
}
.page-about .ver__radio {
  position: absolute;
  width: 1px;
  height: 1px;
  margin: -1px;
  padding: 0;
  overflow: hidden;
  clip: rect(0 0 0 0);
  white-space: nowrap;
  border: 0;
}
.page-about .ver__tabs {
  display: flex;
  flex-wrap: wrap;
  gap: 8px;
  margin-bottom: 18px;
}
.page-about .ver__tab {
  display: inline-flex;
  align-items: center;
  gap: 8px;
  padding: 8px 14px;
  font-size: 13px;
  color: var(--about-on-dark);
  border: 1px solid rgba(255, 255, 255, 0.26);
  border-radius: 999px;
  cursor: pointer;
  transition: background-color 0.2s var(--ease), border-color 0.2s var(--ease), color 0.2s var(--ease);
}
.page-about .ver__tab .num {
  font-size: 12px;
  letter-spacing: 0.06em;
}
.page-about .ver__tab:hover {
  border-color: var(--teal);
  color: var(--white);
}
.page-about #ver10:checked ~ .ver__tabs .ver__tab[for="ver10"],
.page-about #ver15:checked ~ .ver__tabs .ver__tab[for="ver15"],
.page-about #ver20:checked ~ .ver__tabs .ver__tab[for="ver20"] {
  background: var(--teal);
  border-color: var(--teal);
  color: var(--pitch-900);
  font-weight: 600;
}
.page-about .ver__panel {
  display: none;
}
.page-about #ver10:checked ~ .ver__panels .ver__panel--v10,
.page-about #ver15:checked ~ .ver__panels .ver__panel--v15,
.page-about #ver20:checked ~ .ver__panels .ver__panel--v20 {
  display: block;
}
.page-about .ver__title {
  font-family: var(--font-display);
  font-size: 19px;
  font-weight: 700;
  line-height: 1.3;
  margin: 0 0 10px;
  color: var(--white);
}
.page-about .ver__text {
  margin: 0;
  font-size: 15px;
  line-height: 1.78;
  color: var(--about-on-dark);
  max-width: 62ch;
}
.page-about .dep {
  display: flex;
  flex-wrap: wrap;
  align-items: center;
  gap: 8px;
  margin-top: 16px;
}
.page-about .dep__sq {
  width: 26px;
  height: 8px;
  border-radius: 2px;
  background: rgba(255, 255, 255, 0.14);
}
.page-about .dep__sq--on {
  background: var(--teal);
}
.page-about .dep__note {
  font-family: var(--font-mono);
  font-size: 12px;
  letter-spacing: 0.04em;
  color: var(--moss);
}

/* ---------- 团队 ---------- */
.page-about .team {
  display: grid;
  grid-template-columns: minmax(0, 1fr);
  gap: 22px;
}
.page-about .team-bar {
  display: grid;
  grid-template-columns: 1fr auto;
  gap: 8px 12px;
  padding: 14px 0;
  border-bottom: 1px dotted var(--line);
}
.page-about .team-bar:first-child {
  border-top: 1px dotted var(--line);
}
.page-about .team-bar__name {
  font-size: 14px;
  font-weight: 600;
  color: var(--ink);
}
.page-about .team-bar__n {
  font-size: 16px;
  color: var(--teal-ink);
}
.page-about .team-bar__track {
  grid-column: 1 / -1;
  display: block;
  height: 6px;
  border-radius: 3px;
  background: var(--line);
  overflow: hidden;
}
.page-about .team-bar__fill {
  display: block;
  height: 100%;
  border-radius: 3px;
  background: linear-gradient(90deg, var(--teal-ink), var(--teal));
}
.page-about .team-bar__fill--a {
  width: 35%;
}
.page-about .team-bar__fill--b {
  width: 42%;
}
.page-about .team-bar__fill--c {
  width: 23%;
}
.page-about .team__media {
  margin: 26px 0 0;
  border: 1px solid var(--line);
  border-radius: 2px 16px 2px 16px;
  overflow: hidden;
}

/* ---------- 赛事分级 ---------- */
.page-about .tiers {
  list-style: none;
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(210px, 1fr));
  gap: 10px;
  margin: 18px 0 0;
  padding: 0;
}
.page-about .tier {
  display: grid;
  grid-template-columns: auto 1fr;
  grid-template-areas: "idx name" "idx desc";
  gap: 3px 12px;
  padding: 14px 16px;
  background: var(--white);
  border: 1px solid var(--line);
  border-radius: 10px 2px 10px 2px;
  transition: border-color 0.2s var(--ease), background-color 0.2s var(--ease);
}
.page-about .tier:hover {
  border-color: var(--teal-ink);
  background: #FBFCFA;
}
.page-about .tier__idx {
  grid-area: idx;
  align-self: center;
  font-size: 12px;
  letter-spacing: 0.08em;
  color: var(--teal-ink);
}
.page-about .tier__name {
  grid-area: name;
  font-size: 15px;
  font-weight: 700;
  color: var(--ink);
}
.page-about .tier__desc {
  grid-area: desc;
  font-size: 13px;
  line-height: 1.6;
  color: var(--moss-ink);
}

/* ---------- 三步流程 ---------- */
.page-about .flow {
  margin-top: 18px;
}
.page-about .flow__svg {
  display: none;
  width: 100%;
  height: auto;
}
.page-about .flow__line {
  fill: none;
  stroke: rgba(43, 232, 176, 0.5);
  stroke-width: 1.5;
  stroke-dasharray: 6 8;
}
.page-about .flow__dot {
  fill: var(--teal);
}
.page-about .flow__ring {
  fill: none;
  stroke: rgba(43, 232, 176, 0.4);
  stroke-width: 1.5;
}
.page-about .flow__t {
  font-family: var(--font-display);
  font-size: 22px;
  font-weight: 700;
  fill: var(--white);
}
.page-about .flow__s {
  font-family: var(--font-body);
  font-size: 15px;
  fill: var(--about-on-dark);
}
.page-about .flow__list {
  list-style: none;
  display: grid;
  gap: 12px;
  margin: 0;
  padding: 0;
}
.page-about .flow__list li {
  display: grid;
  grid-template-columns: auto 1fr;
  gap: 2px 12px;
  padding: 14px 16px;
  background: rgba(255, 255, 255, 0.06);
  border-left: 2px solid var(--teal);
  border-radius: 2px 12px 2px 12px;
}
.page-about .flow__list-no {
  grid-row: 1 / 3;
  align-self: start;
  font-size: 12px;
  letter-spacing: 0.06em;
  color: var(--teal);
}
.page-about .flow__list strong {
  font-size: 15px;
  color: var(--white);
}
.page-about .flow__list span:last-child {
  font-size: 13px;
  line-height: 1.65;
  color: var(--about-on-dark);
}
.page-about .flow__note {
  margin: 16px 0 0;
  padding-left: 12px;
  border-left: 2px solid var(--yellow);
  font-size: 13px;
  line-height: 1.72;
  color: var(--about-on-dark);
  max-width: 60ch;
}

/* ---------- 每周三 ---------- */
.page-about .split {
  display: grid;
  grid-template-columns: minmax(0, 1fr);
  gap: 22px;
  margin-top: 4px;
}
.page-about .tagrow {
  list-style: none;
  display: flex;
  flex-wrap: wrap;
  gap: 8px;
  margin: 16px 0 0;
  padding: 0;
}
.page-about .tag {
  font-size: 12px;
  letter-spacing: 0.06em;
  padding: 5px 11px;
  border: 1px solid var(--line);
  border-radius: 999px;
  color: var(--moss-ink);
  background: var(--white);
}
.page-about .split__media {
  margin: 0;
  border: 1px solid var(--line);
  border-radius: 2px 16px 2px 16px;
  overflow: hidden;
}

/* ---------- 更正 ---------- */
.page-about .fix {
  padding: 20px 20px 22px;
  background: var(--white);
  border: 1px solid var(--line);
  border-top: 3px solid var(--red);
  border-radius: 2px 16px 2px 16px;
}
.page-about .fix .ng-btn {
  margin-top: 16px;
}

/* ---------- 平板 ---------- */
@media (min-width: 700px) {
  .page-about .about-hero {
    padding: 38px 0 54px;
  }
  .page-about .team {
    grid-template-columns: minmax(0, 1.15fr) minmax(0, 0.85fr);
    gap: 32px;
    align-items: start;
  }
  .page-about .about-sec {
    padding: 36px 0 42px;
  }
}

@media (min-width: 760px) {
  .page-about .flow__svg {
    display: block;
    margin: 4px 0 2px;
  }
  .page-about .flow__list {
    display: none;
  }
  .page-about .about-sec--dark {
    padding: 34px 34px 38px;
    margin: 22px 0;
  }
  .page-about .ver__ghost {
    font-size: 160px;
    top: -24px;
  }
}

/* ---------- 桌面 ---------- */
@media (min-width: 900px) {
  .page-about .about-hero__grid {
    grid-template-columns: minmax(0, 1.02fr) minmax(0, 0.98fr);
    align-items: end;
    gap: 44px;
  }
  .page-about .about-hero h1 {
    max-width: 12ch;
  }
  .page-about .about-shell {
    grid-template-columns: var(--about-rail) minmax(0, 1fr);
    gap: 52px;
    padding-top: 16px;
  }
  .page-about .about-rail {
    display: block;
    position: sticky;
    top: calc(var(--header-h) + 34px);
    align-self: start;
    padding-top: 22px;
  }
  .page-about .about-rail__label {
    margin: 0 0 16px;
    font-size: 11px;
    letter-spacing: 0.14em;
    text-transform: uppercase;
    color: var(--moss-ink);
  }
  .page-about .about-rail__list {
    list-style: none;
    margin: 0;
    padding: 0;
    position: relative;
  }
  .page-about .about-rail__list::before {
    content: "";
    position: absolute;
    left: 5px;
    top: 8px;
    bottom: 8px;
    width: 1px;
    background: linear-gradient(var(--line), var(--teal-ink));
  }
  .page-about .about-rail__item {
    position: relative;
  }
  .page-about .about-rail__link {
    position: relative;
    display: flex;
    align-items: baseline;
    gap: 10px;
    padding: 7px 0 7px 22px;
    font-size: 13px;
    color: var(--moss-ink);
    text-decoration: none;
    transition: color 0.18s var(--ease);
  }
  .page-about .about-rail__link::before {
    content: "";
    position: absolute;
    left: 2px;
    top: 12px;
    width: 7px;
    height: 7px;
    border-radius: 50%;
    background: var(--paper);
    border: 1px solid var(--line);
    transition: background-color 0.18s var(--ease), border-color 0.18s var(--ease);
  }
  .page-about .about-rail__link:hover,
  .page-about .about-rail__link:focus-visible {
    color: var(--pitch-800);
  }
  .page-about .about-rail__link:hover::before,
  .page-about .about-rail__link:focus-visible::before {
    background: var(--teal);
    border-color: var(--teal-ink);
  }
  .page-about .about-rail__no {
    font-size: 11px;
    color: var(--teal-ink);
  }
  .page-about .about-rail__name {
    font-weight: 600;
  }
  .page-about .about-rail__foot {
    display: flex;
    align-items: center;
    gap: 8px;
    margin: 24px 0 0;
    font-size: 11px;
    letter-spacing: 0.1em;
    color: var(--moss-ink);
  }
  .page-about .about-rail__dot {
    width: 6px;
    height: 6px;
    border-radius: 50%;
    background: var(--red);
    box-shadow: 0 0 0 3px rgba(230, 57, 70, 0.16);
  }
  .page-about .sec-cols {
    display: grid;
    grid-template-columns: minmax(0, 1.6fr) minmax(0, 1fr);
    gap: 38px;
    align-items: start;
  }
  .page-about .sec-note {
    margin-top: 4px;
  }
  .page-about .split {
    grid-template-columns: minmax(0, 1.05fr) minmax(0, 0.95fr);
    gap: 34px;
    align-items: start;
  }
  .page-about .about-sec {
    padding: 42px 0 50px;
  }
  .page-about .about-sec--dark {
    padding: 42px 42px 46px;
    margin: 26px 0;
  }
}

@media (prefers-reduced-motion: reduce) {
  .page-about .ver__tab,
  .page-about .tier,
  .page-about .about-rail__link,
  .page-about .about-rail__link::before {
    transition: none;
  }
}
</main>