.page-about {
  --about-rail: 34px;
  background: var(--frost);
  color: var(--graphite);
  overflow-x: clip;
}

@media (min-width: 720px) {
  .page-about {
    --about-rail: 56px;
  }
}

/* 面包屑 */
.page-about .about-crumb {
  padding-top: clamp(14px, 2.5vw, 26px);
  font-size: 12px;
}

/* 首屏 */
.page-about .about-hero {
  display: grid;
  gap: clamp(22px, 4vw, 44px);
  padding-block: clamp(20px, 3vw, 34px) clamp(30px, 5vw, 56px);
}

@media (min-width: 900px) {
  .page-about .about-hero {
    grid-template-columns: minmax(0, 1.05fr) minmax(0, 0.95fr);
    align-items: center;
    gap: clamp(32px, 4vw, 56px);
  }
}

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

.page-about .about-hero h1 {
  margin: 0 0 18px;
  font-family: var(--font-display);
  font-size: clamp(29px, 5.4vw, 54px);
  line-height: 1.1;
  font-weight: 800;
  letter-spacing: -0.02em;
  color: var(--ink);
}

.page-about .about-hero .lede {
  margin: 0;
  max-width: 60ch;
}

.page-about .about-hero__fig {
  margin: 0;
  position: relative;
}

.page-about .about-hero__fig img {
  display: block;
  width: 100%;
  height: auto;
  aspect-ratio: 16 / 9;
  object-fit: cover;
  border-radius: var(--radius);
}

@media (min-width: 900px) {
  .page-about .about-hero__fig img {
    aspect-ratio: 16 / 10;
    clip-path: polygon(0 7%, 100% 0, 100% 93%, 0 100%);
    border-radius: 0;
  }
}

/* 页面索引刻度 */
.page-about .about-index {
  display: flex;
  gap: clamp(14px, 2.6vw, 30px);
  overflow-x: auto;
  padding: 14px 0 12px;
  border-top: 1px solid var(--mist);
  border-bottom: 1px solid var(--mist);
  scrollbar-width: none;
}

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

.page-about .about-index a {
  flex: none;
  display: inline-flex;
  align-items: baseline;
  gap: 7px;
  padding-bottom: 3px;
  border-bottom: 2px solid transparent;
  font-family: var(--font-mono);
  font-size: 12px;
  letter-spacing: 0.1em;
  color: var(--brand);
  text-decoration: none;
  white-space: nowrap;
  transition: color 0.2s var(--ease), border-color 0.2s var(--ease);
}

.page-about .about-index a:hover,
.page-about .about-index a:focus-visible {
  color: var(--ink);
  border-bottom-color: var(--gold);
}

.page-about .about-index__no {
  font-size: 10px;
  color: var(--line-cyan);
}

/* 纵向时间轴 */
.page-about .about-flow {
  position: relative;
  padding-top: clamp(36px, 6vw, 72px);
}

.page-about .about-flow::before {
  content: "";
  position: absolute;
  top: 0;
  bottom: clamp(40px, 8vw, 88px);
  left: calc(var(--about-rail) / 2);
  width: 1px;
  background: linear-gradient(180deg, var(--line-cyan) 0%, var(--mist) 58%, rgba(220, 230, 233, 0) 100%);
}

.page-about .tl-sec {
  display: grid;
  grid-template-columns: var(--about-rail) minmax(0, 1fr);
  column-gap: clamp(14px, 3vw, 36px);
  padding-bottom: clamp(44px, 7vw, 88px);
  scroll-margin-top: 96px;
}

.page-about .tl-sec--last {
  padding-bottom: clamp(20px, 4vw, 40px);
}

.page-about .tl-rail {
  display: flex;
  flex-direction: column;
  align-items: center;
  gap: 9px;
  padding-top: 3px;
}

.page-about .tl-tag {
  max-width: 100%;
  font-family: var(--font-mono);
  font-size: 9px;
  line-height: 1.3;
  letter-spacing: 0.04em;
  text-align: center;
  color: var(--line-cyan);
  overflow-wrap: anywhere;
}

.page-about .tl-dot {
  flex: none;
  width: 9px;
  height: 9px;
  border-radius: 50%;
  background: var(--gold);
  box-shadow: 0 0 0 3px var(--frost);
}

.page-about .tl-body {
  min-width: 0;
}

.page-about .tl-body h2 {
  margin: 8px 0 14px;
  font-family: var(--font-display);
  font-size: clamp(21px, 3.4vw, 33px);
  line-height: 1.22;
  font-weight: 700;
  letter-spacing: -0.01em;
  color: var(--ink);
}

.page-about .tl-body > p:not([class]) {
  max-width: 62ch;
  margin: 0 0 14px;
  font-size: 16px;
  line-height: 1.85;
}

.page-about .tl-body > p:not([class]) a {
  color: var(--line-cyan);
  text-underline-offset: 3px;
}

.page-about .tl-note {
  margin: 20px 0 0;
  padding-left: 12px;
  border-left: 2px solid var(--mist);
  font-size: 14px;
  line-height: 1.8;
  color: var(--brand);
}

.page-about .tl-note a {
  color: var(--line-cyan);
  text-underline-offset: 3px;
}

.page-about .tl-note a:hover {
  color: var(--ink);
}

/* 从终场到回看：阶梯技能树 */
.page-about .flow-stage {
  margin-top: clamp(20px, 3vw, 28px);
  padding: clamp(16px, 3.4vw, 34px);
  border-radius: var(--radius);
  background-color: var(--ink);
  background-image: linear-gradient(118deg, rgba(31, 122, 148, 0.4), rgba(11, 33, 48, 0) 64%);
}

.page-about .steps {
  list-style: none;
  margin: 0;
  padding: 0;
  display: grid;
  gap: 12px;
}

.page-about .step {
  position: relative;
  background: var(--glass-white);
  border-left: 3px solid var(--line-cyan);
  border-radius: var(--radius);
  padding: 16px clamp(14px, 2.6vw, 22px);
  transition: transform 0.25s var(--ease), border-left-color 0.25s var(--ease);
}

.page-about .step:hover,
.page-about .step:focus-within {
  transform: translateX(4px);
  border-left-color: var(--gold);
}

@media (min-width: 760px) {
  .page-about .step:nth-child(2) {
    margin-left: 5%;
  }
  .page-about .step:nth-child(3) {
    margin-left: 10%;
  }
  .page-about .step:nth-child(4) {
    margin-left: 15%;
  }
}

.page-about .step__no {
  display: inline-block;
  font-family: var(--font-mono);
  font-size: 11px;
  font-weight: 700;
  letter-spacing: 0.14em;
  color: var(--line-cyan);
}

.page-about .step__title {
  margin: 4px 0 8px;
  font-family: var(--font-display);
  font-size: 18px;
  font-weight: 700;
  color: var(--ink);
}

.page-about .step__text {
  margin: 0;
  max-width: 58ch;
  font-size: 15px;
  line-height: 1.8;
  color: var(--graphite);
}

.page-about .step__meta {
  display: flex;
  flex-wrap: wrap;
  gap: 8px;
  margin: 12px 0 0;
}

.page-about .step__meta span {
  padding: 3px 9px;
  border-radius: 999px;
  background: var(--mist);
  font-family: var(--font-mono);
  font-size: 11px;
  letter-spacing: 0.06em;
  color: var(--brand);
}

/* 图片 */
.page-about .about-media {
  margin: clamp(20px, 3vw, 30px) 0;
}

.page-about .about-media img {
  display: block;
  width: 100%;
  height: auto;
  aspect-ratio: 3 / 2;
  object-fit: cover;
  border-radius: var(--radius);
}

.page-about .about-media--wide img {
  aspect-ratio: 4 / 3;
}

.page-about .about-media figcaption {
  margin-top: 10px;
  font-family: var(--font-mono);
  font-size: 11px;
  line-height: 1.7;
  letter-spacing: 0.06em;
  color: var(--line-cyan);
}

/* 班次筛选 */
.page-about .shift-scope {
  margin-top: clamp(18px, 3vw, 26px);
}

.page-about .shift-bar {
  display: flex;
  flex-wrap: wrap;
  gap: 8px;
  margin-bottom: 12px;
}

.page-about .shift-bar .filterbar__btn {
  padding: 7px 14px;
  border: 1px solid var(--mist);
  border-radius: 999px;
  background: transparent;
  font-family: var(--font-mono);
  font-size: 12px;
  letter-spacing: 0.06em;
  color: var(--brand);
  cursor: pointer;
  transition: background 0.2s var(--ease), border-color 0.2s var(--ease), color 0.2s var(--ease);
}

.page-about .shift-bar .filterbar__btn:hover {
  border-color: var(--line-cyan);
}

.page-about .shift-bar .filterbar__btn[aria-pressed="true"] {
  background: var(--brand);
  border-color: var(--brand);
  color: var(--frost);
}

.page-about .filterbar__status {
  margin: 0 0 12px;
  font-family: var(--font-mono);
  font-size: 11px;
  letter-spacing: 0.08em;
  color: var(--line-cyan);
}

.page-about .shifts {
  list-style: none;
  margin: 0;
  padding: 0;
  border-top: 1px solid var(--mist);
}

.page-about .shift {
  display: grid;
  grid-template-columns: 60px minmax(0, 1fr);
  gap: 4px 12px;
  align-items: baseline;
  padding: 14px 0;
  border-bottom: 1px solid var(--mist);
}

@media (min-width: 640px) {
  .page-about .shift {
    grid-template-columns: 68px 104px minmax(0, 1fr);
    gap: 4px 14px;
  }
}

.page-about .shift__band {
  justify-self: start;
  padding: 3px 7px;
  border-radius: 2px;
  font-family: var(--font-mono);
  font-size: 10px;
  letter-spacing: 0.1em;
  color: var(--frost);
  background: var(--line-cyan);
}

.page-about .shift__band--late {
  background: var(--brand);
}

.page-about .shift__band--night {
  background: var(--ink);
}

.page-about .shift__role {
  font-size: 15px;
  font-weight: 700;
  color: var(--ink);
}

.page-about .shift__desc {
  grid-column: 2 / -1;
  font-size: 14px;
  line-height: 1.75;
  color: var(--graphite);
}

@media (min-width: 640px) {
  .page-about .shift__desc {
    grid-column: 3 / -1;
  }
}

/* 协作双栏 */
.page-about .about-pair {
  margin-top: clamp(18px, 3vw, 26px);
  gap: clamp(12px, 2vw, 20px);
}

.page-about .about-pair__item {
  padding: 18px clamp(14px, 2.4vw, 20px);
  border-top: 2px solid var(--line-cyan);
  border-radius: var(--radius);
  background: var(--glass-white);
  box-shadow: 0 1px 0 var(--mist);
}

.page-about .about-pair__item h3 {
  margin: 0 0 8px;
  font-size: 17px;
  font-weight: 700;
  color: var(--ink);
}

.page-about .about-pair__item p {
  margin: 0;
  font-size: 15px;
  line-height: 1.8;
}

/* 赛季节奏 */
.page-about .seasons {
  list-style: none;
  margin: clamp(18px, 3vw, 28px) 0 0;
  padding: 0;
  display: grid;
  gap: 10px;
}

@media (min-width: 820px) {
  .page-about .seasons {
    grid-template-columns: repeat(5, minmax(0, 1fr));
  }
}

.page-about .season {
  display: flex;
  flex-direction: column;
  gap: 6px;
  padding: 14px;
  border-radius: var(--radius);
  background: var(--mist);
  border-top: 3px solid rgba(31, 122, 148, 0.45);
}

.page-about .season:nth-child(4) {
  border-top-color: var(--gold);
}

.page-about .season:nth-child(5) {
  border-top-color: var(--lake);
}

.page-about .season__no {
  font-family: var(--font-mono);
  font-size: 11px;
  letter-spacing: 0.12em;
  color: var(--line-cyan);
}

.page-about .season h3 {
  margin: 0;
  font-size: 15px;
  font-weight: 700;
  color: var(--ink);
}

.page-about .season p {
  margin: 0;
  font-size: 14px;
  line-height: 1.75;
  color: var(--graphite);
}

/* 规则清单 */
.page-about .ledger {
  list-style: none;
  margin: clamp(16px, 3vw, 26px) 0 0;
  padding: 0;
}

.page-about .ledger__item {
  display: grid;
  grid-template-columns: 38px minmax(0, 1fr);
  gap: 12px;
  padding: 16px 0;
  border-top: 1px solid var(--mist);
}

.page-about .ledger__item:last-child {
  border-bottom: 1px solid var(--mist);
}

.page-about .ledger__no {
  padding-top: 3px;
  font-family: var(--font-mono);
  font-size: 12px;
  font-weight: 700;
  letter-spacing: 0.1em;
  color: var(--line-cyan);
}

.page-about .ledger__body h3 {
  margin: 0 0 6px;
  font-size: 16px;
  font-weight: 700;
  color: var(--ink);
}

.page-about .ledger__body p {
  margin: 0;
  max-width: 58ch;
  font-size: 15px;
  line-height: 1.8;
}

/* 合作入口 */
.page-about .join {
  padding: clamp(22px, 4vw, 40px);
  border-top: 3px solid var(--gold);
  border-radius: var(--radius);
  color: var(--frost);
  background-color: var(--brand);
  background-image: linear-gradient(122deg, rgba(53, 169, 140, 0.3), rgba(16, 70, 92, 0) 62%);
}

.page-about .join__title {
  margin: 0 0 12px;
  font-family: var(--font-display);
  font-size: clamp(20px, 3vw, 28px);
  font-weight: 700;
  letter-spacing: -0.01em;
  color: var(--frost);
}

.page-about .join p {
  margin: 0;
  max-width: 56ch;
  font-size: 15px;
  line-height: 1.85;
  color: rgba(244, 247, 248, 0.86);
}

.page-about .join__actions {
  display: flex;
  flex-wrap: wrap;
  gap: 12px;
  margin-top: 20px;
}

.page-about .join__actions .btn--line {
  border-color: rgba(244, 247, 248, 0.5);
  color: var(--frost);
}

.page-about .join__actions .btn--line:hover,
.page-about .join__actions .btn--line:focus-visible {
  border-color: var(--gold);
  color: var(--gold);
}
<<<END>>>