.page-about {
  --about-cut: 18px;
  --about-hair: rgba(47, 214, 255, .18);
  position: relative;
  overflow-x: clip;
}

/* ---------- 面包屑 ---------- */
.page-about .about-crumbs {
  padding: clamp(20px, 4vw, 40px) 0 0;
}
.page-about .breadcrumbs ol {
  display: flex;
  flex-wrap: wrap;
  align-items: center;
  gap: 6px;
  margin: 0;
  padding: 0;
  list-style: none;
  font-size: 13px;
  color: var(--c-mist);
}
.page-about .breadcrumbs li + li::before {
  content: "/";
  margin-right: 6px;
  color: rgba(154, 179, 204, .6);
}
.page-about .breadcrumbs a {
  color: var(--c-mist);
  text-decoration: none;
}
.page-about .breadcrumbs a:hover,
.page-about .breadcrumbs a:focus-visible {
  color: var(--c-orange);
}
.page-about .breadcrumbs [aria-current="page"] {
  color: var(--c-ice);
}

/* ---------- 首屏 ---------- */
.page-about .about-hero {
  padding: clamp(28px, 6vw, 54px) 0 clamp(16px, 3vw, 26px);
}
.page-about .about-hero__grid {
  display: grid;
  gap: clamp(28px, 5vw, 56px);
}
.page-about .about-hero__title {
  font-size: clamp(38px, 8.6vw, 90px);
  line-height: .98;
  letter-spacing: -.015em;
  margin: 14px 0 20px;
}
.page-about .about-hero__actions {
  display: flex;
  flex-wrap: wrap;
  gap: 12px;
  margin-top: 26px;
}
.page-about .about-hero__rail {
  display: grid;
  gap: 14px;
  align-content: start;
  padding: clamp(20px, 3vw, 28px);
  background: linear-gradient(180deg, rgba(18, 42, 71, .95), rgba(10, 26, 47, .7));
  border: 1px solid var(--about-hair);
  border-left: 3px solid var(--c-orange);
  clip-path: polygon(0 0, 100% 0, 100% calc(100% - var(--about-cut)), calc(100% - var(--about-cut)) 100%, 0 100%);
}
.page-about .about-fact {
  display: flex;
  align-items: baseline;
  gap: 12px;
  padding-bottom: 10px;
  border-bottom: 1px dashed rgba(47, 214, 255, .14);
}
.page-about .about-fact:last-of-type {
  border-bottom: 0;
}
.page-about .about-fact__num {
  font-family: var(--font-mono);
  font-size: clamp(24px, 4vw, 32px);
  font-weight: 700;
  line-height: 1;
  color: var(--c-ice);
}
.page-about .about-fact__num--live {
  color: var(--c-neon);
}
.page-about .about-fact__label {
  font-size: 13px;
  color: var(--c-mist);
}

/* ---------- 章节索引 ---------- */
.page-about .about-index {
  margin-top: clamp(28px, 5vw, 52px);
  border-top: 1px solid var(--about-hair);
  border-bottom: 1px solid rgba(47, 214, 255, .1);
  background: linear-gradient(90deg, rgba(18, 42, 71, .5), transparent 72%);
}
.page-about .about-index ol {
  display: flex;
  gap: clamp(14px, 3vw, 34px);
  overflow-x: auto;
  margin: 0;
  padding: 14px 0 12px;
  list-style: none;
}
.page-about .about-index a {
  display: inline-flex;
  align-items: baseline;
  gap: 8px;
  white-space: nowrap;
  font-size: 14px;
  color: var(--c-mist);
  text-decoration: none;
  transition: color .2s var(--ease);
}
.page-about .about-index a:hover,
.page-about .about-index a:focus-visible {
  color: var(--c-orange);
}
.page-about .about-index .num {
  font-family: var(--font-mono);
  font-size: 12px;
  letter-spacing: .06em;
  color: var(--c-orange);
}

/* ---------- 章节骨架 ---------- */
.page-about .about-chapter {
  position: relative;
  padding: clamp(48px, 8vw, 100px) 0;
}
.page-about .about-chapter + .about-chapter::before {
  content: "";
  position: absolute;
  top: 0;
  left: 4%;
  right: 4%;
  height: 2px;
  transform: rotate(-.7deg);
  background: linear-gradient(90deg, transparent, rgba(255, 107, 44, .55) 22%, rgba(47, 214, 255, .45) 78%, transparent);
}
.page-about .about-chapter__head {
  display: grid;
  gap: 6px;
  margin-bottom: clamp(24px, 4vw, 42px);
}
.page-about .about-chapter__no {
  font-family: var(--font-mono);
  font-size: clamp(34px, 7vw, 76px);
  font-weight: 700;
  line-height: 1;
  letter-spacing: .04em;
  color: rgba(255, 107, 44, .2);
  -webkit-text-stroke: 1px rgba(255, 107, 44, .55);
}
.page-about .about-chapter__body {
  display: grid;
  gap: clamp(24px, 4vw, 48px);
}
.page-about .about-chapter__main {
  min-width: 0;
  display: grid;
  gap: clamp(20px, 3vw, 30px);
  align-content: start;
}

/* ---------- 正文 ---------- */
.page-about .about-prose {
  max-width: 62ch;
  font-size: clamp(16px, 1.6vw, 17.5px);
  line-height: 1.85;
  color: var(--c-ice);
}
.page-about .about-prose p {
  margin: 0 0 1.05em;
}
.page-about .about-prose p:last-child {
  margin-bottom: 0;
}

/* ---------- 窄栏注释 ---------- */
.page-about .about-rail {
  display: grid;
  gap: 14px;
  align-content: start;
}
.page-about .about-rail__card {
  padding: 16px 18px;
  background: rgba(18, 42, 71, .66);
  border-left: 2px solid rgba(255, 107, 44, .75);
  font-size: 14px;
  line-height: 1.8;
  color: var(--c-ice);
}
.page-about .about-rail__card p {
  margin: 0;
}
.page-about .about-rail__card p + p {
  margin-top: 8px;
}
.page-about .about-rail p.about-rail__label {
  margin: 0 0 6px;
  font-family: var(--font-mono);
  font-size: 11.5px;
  letter-spacing: .16em;
  text-transform: uppercase;
  color: var(--c-orange);
}

/* ---------- 团队角色卡 ---------- */
.page-about .about-roles {
  display: grid;
  gap: 14px;
}
.page-about .about-role {
  padding: 20px 20px 22px;
  background: linear-gradient(160deg, rgba(30, 58, 95, .72), rgba(18, 42, 71, .45));
  border: 1px solid var(--about-hair);
  clip-path: polygon(var(--about-cut) 0, 100% 0, 100% 100%, 0 100%, 0 var(--about-cut));
  transition: transform .24s var(--ease), border-color .24s var(--ease);
}
.page-about .about-role:hover {
  transform: translateY(-6px);
  border-color: rgba(255, 107, 44, .6);
}
.page-about .about-role__title {
  margin: 0 0 10px;
  font-size: 18px;
  font-weight: 700;
  color: #ffffff;
}
.page-about .about-role__title::before {
  content: "";
  display: inline-block;
  width: 18px;
  height: 2px;
  margin-right: 10px;
  vertical-align: middle;
  background: var(--c-orange);
}
.page-about .about-role p {
  margin: 0;
  font-size: 14.5px;
  line-height: 1.8;
  color: var(--c-mist);
}

/* ---------- 图片容器 ---------- */
.page-about .about-figure,
.page-about .about-banner {
  margin: 0;
}
.page-about .about-banner {
  margin-bottom: clamp(28px, 4vw, 48px);
}
.page-about .about-figure img,
.page-about .about-banner img {
  display: block;
  width: 100%;
  max-width: 100%;
  height: auto;
  object-fit: cover;
}
.page-about .about-figure .figure__caption,
.page-about .about-banner .figure__caption {
  margin-top: 10px;
  font-size: 13px;
  color: var(--c-mist);
}

/* ---------- 比分链路 ---------- */
.page-about .about-flow {
  list-style: none;
  margin: 0;
  padding: 0;
  display: grid;
  gap: 12px;
}
.page-about .about-flow li {
  display: grid;
  grid-template-columns: auto minmax(0, 1fr);
  gap: 14px;
  padding: 16px 18px;
  background: rgba(18, 42, 71, .5);
  border-left: 2px solid rgba(47, 214, 255, .35);
  transition: border-color .22s var(--ease), background .22s var(--ease);
}
.page-about .about-flow li:hover {
  border-left-color: var(--c-neon);
  background: rgba(18, 42, 71, .78);
}
.page-about .about-flow__step {
  padding-top: 2px;
  font-family: var(--font-mono);
  font-size: 13px;
  color: var(--c-orange);
}
.page-about .about-flow__title {
  margin: 0 0 6px;
  font-size: 16px;
  font-weight: 700;
  color: #ffffff;
}
.page-about .about-flow li p {
  margin: 0;
  font-size: 14.5px;
  line-height: 1.78;
  color: var(--c-mist);
}
.page-about .about-chart {
  padding: clamp(16px, 3vw, 24px);
  background: rgba(10, 26, 47, .72);
  border: 1px solid var(--about-hair);
}
.page-about .about-chart__title {
  margin: 0 0 14px;
  font-family: var(--font-mono);
  font-size: 12.5px;
  letter-spacing: .1em;
  color: var(--c-mist);
}
.page-about .about-chart svg {
  display: block;
  width: 100%;
  height: auto;
}
.page-about .about-chart .chart-axis {
  stroke: rgba(154, 179, 204, .28);
  stroke-width: 1;
}
.page-about .about-chart .chart-area {
  fill: rgba(47, 214, 255, .12);
  stroke: none;
}
.page-about .about-chart .chart-line {
  fill: none;
  stroke: var(--c-cyan);
  stroke-width: 2.5;
  stroke-linecap: round;
  stroke-linejoin: round;
}
.page-about .about-chart .chart-dot {
  fill: var(--c-arena);
  stroke: var(--c-neon);
  stroke-width: 2;
}
.page-about .about-chart .chart-label {
  fill: var(--c-mist);
  font-family: var(--font-mono);
  font-size: 11px;
}
.page-about .about-chart .note {
  margin-top: 12px;
}

/* ---------- 会员档位 ---------- */
.page-about .about-tiers {
  display: grid;
  grid-auto-flow: column;
  grid-auto-columns: minmax(250px, 80%);
  gap: 14px;
  overflow-x: auto;
  padding-bottom: 10px;
  scroll-snap-type: x mandatory;
}
.page-about .about-tier {
  scroll-snap-align: start;
  display: grid;
  gap: 12px;
  align-content: start;
  padding: 22px 20px 24px;
  background: linear-gradient(165deg, rgba(30, 58, 95, .78), rgba(18, 42, 71, .5));
  border: 1px solid var(--about-hair);
  clip-path: polygon(var(--about-cut) 0, 100% 0, 100% 100%, 0 100%, 0 var(--about-cut));
}
.page-about .about-tier--stable {
  border-color: rgba(255, 176, 32, .55);
  background: linear-gradient(165deg, rgba(74, 20, 48, .9), rgba(18, 42, 71, .62));
}
.page-about .about-tier__name {
  margin: 0;
  font-size: 19px;
  font-weight: 700;
  color: #ffffff;
}
.page-about .about-tier__desc {
  margin: 0;
  font-size: 14.5px;
  line-height: 1.8;
  color: var(--c-ice);
}
.page-about .about-tier__list {
  list-style: none;
  margin: 0;
  padding: 0;
  display: grid;
  gap: 8px;
  font-size: 14px;
  color: var(--c-mist);
}
.page-about .about-tier__list li {
  position: relative;
  padding-left: 16px;
  line-height: 1.7;
}
.page-about .about-tier__list li::before {
  content: "";
  position: absolute;
  left: 0;
  top: .62em;
  width: 6px;
  height: 6px;
  border-radius: 50%;
  background: var(--c-orange);
}
.page-about .about-tier--stable .about-tier__list li::before {
  background: var(--c-neon);
}

/* ---------- 版本时间线 ---------- */
.page-about .about-versions {
  position: relative;
  list-style: none;
  margin: 0;
  padding: 0 0 0 26px;
  display: grid;
  gap: 26px;
}
.page-about .about-versions::before {
  content: "";
  position: absolute;
  left: 7px;
  top: 6px;
  bottom: 6px;
  width: 2px;
  background: linear-gradient(180deg, var(--c-orange), rgba(47, 214, 255, .55) 55%, rgba(47, 214, 255, 0));
}
.page-about .ver {
  position: relative;
}
.page-about .ver::before {
  content: "";
  position: absolute;
  left: -24px;
  top: 5px;
  width: 12px;
  height: 12px;
  border-radius: 50%;
  background: var(--c-arena);
  border: 2px solid var(--c-orange);
  transition: border-color .22s var(--ease), box-shadow .22s var(--ease);
}
.page-about .ver--live::before {
  border-color: var(--c-neon);
  box-shadow: 0 0 0 5px rgba(57, 255, 20, .14);
}
.page-about .ver__tag {
  margin: 0 0 6px;
  font-family: var(--font-mono);
  font-size: 12px;
  letter-spacing: .1em;
  color: var(--c-orange);
}
.page-about .ver__title {
  margin: 0 0 6px;
  font-size: 17px;
  font-weight: 700;
  color: #ffffff;
}
.page-about .ver__note {
  margin: 0;
  font-size: 14.5px;
  line-height: 1.8;
  color: var(--c-mist);
  transition: color .22s var(--ease), transform .22s var(--ease);
}

/* ---------- 服务与支持 ---------- */
.page-about .about-coverage {
  display: grid;
  gap: clamp(24px, 4vw, 44px);
}
.page-about .about-coverage__main {
  display: grid;
  gap: 18px;
  align-content: start;
  max-width: 62ch;
}
.page-about .about-coverage__main p {
  margin: 0;
  font-size: clamp(16px, 1.6vw, 17.5px);
  line-height: 1.85;
  color: var(--c-ice);
}
.page-about .about-contact-list {
  list-style: none;
  margin: 0;
  padding: 0;
  display: grid;
  gap: 10px;
}
.page-about .about-contact-list li {
  display: flex;
  flex-wrap: wrap;
  gap: 10px;
  padding-bottom: 10px;
  border-bottom: 1px dashed rgba(47, 214, 255, .14);
  font-size: 14.5px;
  color: var(--c-ice);
}
.page-about .about-contact-list__key {
  min-width: 84px;
  padding-top: 3px;
  font-family: var(--font-mono);
  font-size: 12px;
  letter-spacing: .1em;
  color: var(--c-orange);
}
.page-about .about-coverage__stats {
  display: grid;
  grid-template-columns: repeat(2, minmax(0, 1fr));
  gap: 12px;
  align-content: start;
}
.page-about .about-stat-card {
  display: grid;
  gap: 6px;
  padding: 18px;
  background: rgba(18, 42, 71, .6);
  border: 1px solid var(--about-hair);
  clip-path: polygon(0 0, 100% 0, 100% calc(100% - 12px), calc(100% - 12px) 100%, 0 100%);
}
.page-about .about-stat-card__num {
  font-family: var(--font-mono);
  font-size: clamp(26px, 5vw, 38px);
  font-weight: 700;
  line-height: 1;
  color: var(--c-neon);
}
.page-about .about-stat-card span:last-child {
  font-size: 13px;
  color: var(--c-mist);
}

/* ---------- 延伸入口 ---------- */
.page-about .about-next {
  padding: clamp(48px, 7vw, 92px) 0 clamp(64px, 9vw, 120px);
}
.page-about .about-next__grid {
  display: grid;
  gap: 14px;
  margin-top: clamp(22px, 3vw, 34px);
}
.page-about .about-next__item {
  display: grid;
  gap: 6px;
  padding: 20px 22px;
  background: rgba(18, 42, 71, .45);
  border-left: 2px solid rgba(255, 107, 44, .5);
  color: inherit;
  text-decoration: none;
  transition: transform .24s var(--ease), background .24s var(--ease), border-color .24s var(--ease);
}
.page-about .about-next__item:hover,
.page-about .about-next__item:focus-visible {
  transform: translateY(-6px);
  background: rgba(30, 58, 95, .75);
  border-left-color: var(--c-orange);
}
.page-about .about-next__k {
  font-family: var(--font-mono);
  font-size: 12px;
  color: var(--c-orange);
}
.page-about .about-next__t {
  font-size: 18px;
  font-weight: 700;
  color: #ffffff;
}
.page-about .about-next__d {
  font-size: 14px;
  line-height: 1.7;
  color: var(--c-mist);
}

/* ---------- 响应式 ---------- */
@media (min-width: 720px) {
  .page-about .about-roles {
    grid-template-columns: repeat(2, minmax(0, 1fr));
  }
  .page-about .about-next__grid {
    grid-template-columns: repeat(2, minmax(0, 1fr));
  }
  .page-about .about-flow li {
    padding: 18px 20px;
  }
}

@media (min-width: 900px) {
  .page-about .about-hero__grid {
    grid-template-columns: minmax(0, 1.55fr) minmax(280px, .9fr);
    gap: clamp(40px, 5vw, 72px);
    align-items: start;
  }
  .page-about .about-tiers {
    grid-auto-flow: row;
    grid-template-columns: repeat(3, minmax(0, 1fr));
    overflow: visible;
    padding-bottom: 0;
  }
  .page-about .about-coverage {
    grid-template-columns: minmax(0, 1.5fr) minmax(240px, .8fr);
  }
}

@media (min-width: 960px) {
  .page-about .about-chapter__head {
    grid-template-columns: auto minmax(0, 1fr);
    align-items: baseline;
    column-gap: 24px;
  }
  .page-about .about-chapter__body {
    grid-template-columns: minmax(0, 1.62fr) minmax(240px, .82fr);
    gap: clamp(32px, 4vw, 64px);
  }
  .page-about .about-chapter__body--flip {
    grid-template-columns: minmax(240px, .82fr) minmax(0, 1.62fr);
  }
  .page-about .about-chapter__body--flip > .about-rail {
    grid-column: 1;
    grid-row: 1;
  }
  .page-about .about-chapter__body--flip > .about-chapter__main {
    grid-column: 2;
    grid-row: 1;
  }
  .page-about .ver:hover .ver__note {
    color: var(--c-ice);
    transform: translateX(4px);
  }
  .page-about .ver:hover::before {
    border-color: var(--c-neon);
  }
}

@media (prefers-reduced-motion: reduce) {
  .page-about .about-role,
  .page-about .about-next__item,
  .page-about .about-flow li,
  .page-about .ver__note,
  .page-about .ver::before {
    transition: none;
  }
  .page-about .about-role:hover,
  .page-about .about-next__item:hover,
  .page-about .ver:hover .ver__note {
    transform: none;
  }
}