.page-about {
  color: var(--mist-100);
}

.page-about .about-crumb {
  padding-top: clamp(16px, 3vw, 28px);
}

/* ---------- 首屏 ---------- */
.page-about .about-hero {
  position: relative;
  padding-block: clamp(28px, 6vw, 72px) clamp(40px, 7vw, 88px);
  border-bottom: 1px solid var(--ink-700);
  overflow: hidden;
}

.page-about .about-hero::after {
  content: "";
  position: absolute;
  top: 0;
  right: 0;
  bottom: 0;
  width: min(34%, 380px);
  background-image: repeating-linear-gradient(
    135deg,
    transparent 0 14px,
    rgba(61, 242, 192, 0.11) 14px 15px
  );
  -webkit-mask-image: linear-gradient(90deg, transparent, #000 70%);
  mask-image: linear-gradient(90deg, transparent, #000 70%);
  pointer-events: none;
}

.page-about .about-hero__title {
  position: relative;
  z-index: 1;
  margin: clamp(14px, 2vw, 22px) 0 0;
  max-width: 13em;
  font-family: var(--font-display);
  font-size: clamp(36px, 7.2vw, 92px);
  font-weight: 700;
  line-height: 0.96;
  letter-spacing: -0.015em;
  text-wrap: balance;
  overflow-wrap: break-word;
}

.page-about .about-hero__lead {
  position: relative;
  z-index: 1;
  margin: clamp(20px, 3vw, 32px) 0 0;
  max-width: 36em;
  font-size: clamp(16px, 1.6vw, 19px);
  line-height: 1.78;
  color: var(--mist-100);
}

.page-about .about-hero__meta {
  position: relative;
  z-index: 1;
  display: grid;
  grid-template-columns: repeat(2, minmax(0, 1fr));
  gap: 20px;
  margin: clamp(28px, 4vw, 46px) 0 0;
  padding: clamp(16px, 2.4vw, 22px) 0 0;
  list-style: none;
  border-top: 1px solid var(--ink-700);
}

.page-about .about-hero__k {
  display: block;
  font-family: var(--font-mono);
  font-size: 12px;
  letter-spacing: 0.08em;
  color: var(--steel-400);
}

.page-about .about-hero__v {
  display: block;
  margin-top: 8px;
  font-family: var(--font-display);
  font-size: clamp(24px, 3.2vw, 36px);
  line-height: 1;
  color: var(--mist-100);
}

.page-about .about-hero__v small {
  margin-left: 4px;
  font-family: var(--font-body);
  font-size: 13px;
  font-weight: 400;
  color: var(--steel-400);
}

/* ---------- 通用区块节奏 ---------- */
.page-about .section {
  padding-block: clamp(40px, 6.5vw, 88px);
}

.page-about .about-split__title {
  margin: 0 0 clamp(16px, 2.4vw, 26px);
  max-width: 16em;
  font-family: var(--font-display);
  font-size: clamp(27px, 4.2vw, 50px);
  font-weight: 700;
  line-height: 1.08;
  letter-spacing: -0.01em;
  text-wrap: balance;
}

/* ---------- 问题 ---------- */
.page-about .about-split {
  display: grid;
  grid-template-columns: minmax(0, 1fr);
  gap: clamp(26px, 4vw, 52px);
}

.page-about .about-split__main p {
  max-width: 36em;
  margin: 0 0 1.1em;
  font-size: 17px;
  line-height: 1.78;
  color: var(--steel-400);
}

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

.page-about .about-pain {
  padding: clamp(20px, 3vw, 30px);
  background: var(--ink-800);
  clip-path: polygon(0 0, calc(100% - 24px) 0, 100% 24px, 100% 100%, 0 100%);
}

.page-about .about-pain__label {
  margin: 0;
  font-family: var(--font-mono);
  font-size: 12px;
  letter-spacing: 0.06em;
  color: var(--signal);
}

.page-about .about-pain ul {
  display: flex;
  flex-direction: column;
  gap: 16px;
  margin: 16px 0 0;
  padding: 0;
  list-style: none;
}

.page-about .about-pain li {
  position: relative;
  padding-left: 20px;
  font-size: 15px;
  line-height: 1.72;
  color: var(--mist-100);
}

.page-about .about-pain li::before {
  content: "";
  position: absolute;
  left: 0;
  top: 0.6em;
  width: 8px;
  height: 8px;
  background: var(--track);
  transform: rotate(45deg);
}

/* ---------- 三条内容线 ---------- */
.page-about .about-lines__intro {
  max-width: 34em;
  margin: 0;
  font-size: 16px;
  line-height: 1.75;
  color: var(--steel-400);
}

.page-about .about-lines__grid {
  display: grid;
  grid-template-columns: minmax(0, 1fr);
  gap: 1px;
  margin-top: clamp(24px, 4vw, 44px);
  background: var(--ink-700);
}

.page-about .about-line {
  display: flex;
  flex-direction: column;
  gap: 12px;
  padding: clamp(22px, 3vw, 34px);
  background: var(--ink-900);
}

.page-about .about-line__num {
  font-family: var(--font-mono);
  font-size: 12px;
  letter-spacing: 0.1em;
  color: var(--signal);
}

.page-about .about-line h3 {
  margin: 0;
  font-family: var(--font-display);
  font-size: clamp(20px, 2.3vw, 26px);
  font-weight: 700;
  line-height: 1.2;
}

.page-about .about-line p {
  margin: 0;
  font-size: 15px;
  line-height: 1.75;
  color: var(--steel-400);
}

.page-about .about-line__facts {
  display: flex;
  flex-direction: column;
  gap: 9px;
  margin: 4px 0 0;
  padding: 0;
  list-style: none;
  font-family: var(--font-mono);
  font-size: 13px;
  line-height: 1.5;
  color: var(--mist-100);
}

.page-about .about-line__facts li {
  display: flex;
  align-items: baseline;
  gap: 10px;
}

.page-about .about-line__facts li::before {
  content: "";
  flex: none;
  width: 14px;
  height: 1px;
  background: var(--teal-700);
}

.page-about .about-line .link-track {
  margin-top: auto;
  padding-top: 8px;
  align-self: flex-start;
  font-family: var(--font-mono);
  font-size: 13px;
}

/* ---------- 生产流程 ---------- */
.page-about .about-flow__grid {
  display: grid;
  grid-template-columns: minmax(0, 1fr);
  gap: clamp(26px, 4vw, 52px);
}

.page-about .about-flow__lead {
  max-width: 34em;
  margin: 0;
  font-size: 16px;
  line-height: 1.78;
  color: var(--steel-400);
}

.page-about .about-steps {
  display: flex;
  flex-direction: column;
  gap: 1px;
  margin: clamp(20px, 3vw, 32px) 0 0;
  padding: 0;
  list-style: none;
  background: var(--ink-700);
}

.page-about .about-steps > li {
  background: var(--ink-900);
}

.page-about .about-steps details {
  padding: clamp(16px, 2.4vw, 24px);
  transition: background var(--dur) var(--ease);
}

.page-about .about-steps details[open] {
  background: var(--ink-800);
}

.page-about .about-steps summary {
  display: flex;
  align-items: baseline;
  gap: 14px;
  cursor: pointer;
  list-style: none;
  font-family: var(--font-display);
  font-size: clamp(18px, 2.2vw, 24px);
  font-weight: 700;
  color: var(--mist-100);
  transition: color var(--dur) var(--ease), transform var(--dur) var(--ease);
}

.page-about .about-steps summary::-webkit-details-marker {
  display: none;
}

.page-about .about-steps summary:hover {
  color: var(--signal);
  transform: translateX(2px);
}

.page-about .about-steps summary:focus-visible {
  outline: 2px solid var(--signal);
  outline-offset: 3px;
}

.page-about .about-steps__num {
  font-family: var(--font-mono);
  font-size: 12px;
  font-weight: 400;
  letter-spacing: 0.08em;
  color: var(--track);
}

.page-about .about-steps details p {
  margin: 12px 0 0;
  padding-left: 34px;
  max-width: 34em;
  font-size: 15px;
  line-height: 1.75;
  color: var(--steel-400);
}

.page-about .about-flow__media {
  margin: 0;
}

.page-about .about-flow__media img {
  display: block;
  width: 100%;
  height: auto;
  aspect-ratio: 3 / 4;
  object-fit: cover;
}

/* ---------- 团队 ---------- */
.page-about .about-team__figure {
  display: flex;
  flex-wrap: wrap;
  align-items: baseline;
  gap: clamp(12px, 2vw, 26px);
  margin: clamp(4px, 1vw, 12px) 0 clamp(24px, 3.5vw, 36px);
  padding-bottom: clamp(16px, 2.4vw, 24px);
  border-bottom: 1px solid var(--ink-700);
}

.page-about .about-team__num {
  font-family: var(--font-mono);
  font-size: clamp(64px, 13vw, 150px);
  font-weight: 700;
  line-height: 0.82;
  letter-spacing: -0.04em;
  color: var(--mist-100);
}

.page-about .about-team__unit {
  font-size: 15px;
  line-height: 1.7;
  color: var(--steel-400);
}

.page-about .about-roles {
  display: grid;
  grid-template-columns: minmax(0, 1fr);
  gap: 1px;
  background: var(--ink-700);
}

.page-about .about-role {
  display: flex;
  flex-direction: column;
  gap: 10px;
  padding: clamp(20px, 3vw, 30px);
  background: var(--ink-900);
  transition: background var(--dur) var(--ease), transform var(--dur) var(--ease);
}

.page-about .about-role:hover,
.page-about .about-role:focus-within {
  background: var(--ink-800);
  transform: translateY(-2px);
}

.page-about .about-role h3 {
  margin: 0;
  font-family: var(--font-display);
  font-size: clamp(18px, 2.2vw, 22px);
  font-weight: 700;
  line-height: 1.25;
}

.page-about .about-role p {
  margin: 0;
  font-size: 15px;
  line-height: 1.72;
  color: var(--steel-400);
}

.page-about .about-role ul {
  display: flex;
  flex-direction: column;
  gap: 8px;
  margin: 4px 0 0;
  padding: 12px 0 0;
  list-style: none;
  border-top: 1px solid var(--ink-700);
  font-size: 14px;
  line-height: 1.6;
  color: var(--mist-100);
}

.page-about .about-role li {
  position: relative;
  padding-left: 16px;
}

.page-about .about-role li::before {
  content: "";
  position: absolute;
  left: 0;
  top: 0.55em;
  width: 6px;
  height: 6px;
  background: var(--teal-700);
  transform: rotate(45deg);
}

/* ---------- 版本 ---------- */
.page-about .about-version__media {
  margin: 0 0 clamp(28px, 4vw, 48px);
}

.page-about .about-version__media img {
  display: block;
  width: 100%;
  height: auto;
  aspect-ratio: 16 / 7;
  object-fit: cover;
}

.page-about .about-version__body {
  max-width: 40em;
}

.page-about .about-version__body > p {
  margin: 0;
  font-size: 16px;
  line-height: 1.78;
  color: var(--steel-400);
}

.page-about .about-timeline {
  position: relative;
  margin: clamp(24px, 3.5vw, 40px) 0 0;
  padding: 0;
  list-style: none;
}

.page-about .about-timeline::before {
  content: "";
  position: absolute;
  left: 7px;
  top: 8px;
  bottom: 8px;
  width: 1px;
  background: linear-gradient(180deg, var(--signal), var(--ink-700));
}

.page-about .about-timeline__item {
  position: relative;
  padding-left: 38px;
  padding-bottom: clamp(24px, 3.4vw, 36px);
}

.page-about .about-timeline__item:last-child {
  padding-bottom: 0;
}

.page-about .about-timeline__item::before {
  content: "";
  position: absolute;
  left: 0;
  top: 8px;
  width: 15px;
  height: 15px;
  background: var(--ink-900);
  border: 1px solid var(--signal);
  transform: rotate(45deg);
  transition: background var(--dur) var(--ease);
}

.page-about .about-timeline__item:hover::before {
  background: var(--signal);
}

.page-about .about-timeline__item--current::before {
  background: var(--signal);
}

.page-about .about-timeline__tag {
  display: inline-flex;
  align-items: center;
  gap: 8px;
  font-size: 12px;
  letter-spacing: 0.1em;
  color: var(--signal);
}

.page-about .about-timeline__now {
  padding: 2px 7px;
  background: var(--signal);
  color: var(--ink-900);
  font-family: var(--font-body);
  font-size: 11px;
  letter-spacing: 0;
}

.page-about .about-timeline__item h3 {
  margin: 10px 0 8px;
  font-family: var(--font-display);
  font-size: clamp(18px, 2.2vw, 24px);
  font-weight: 700;
  line-height: 1.25;
}

.page-about .about-timeline__item p {
  margin: 0;
  max-width: 34em;
  font-size: 15px;
  line-height: 1.78;
  color: var(--steel-400);
}

.page-about .about-version__note {
  margin-top: clamp(24px, 3vw, 34px);
  padding-top: clamp(16px, 2.2vw, 22px);
  border-top: 1px solid var(--ink-700);
}

.page-about .about-version__note .link-track {
  margin-left: 4px;
}

/* ---------- 合作与覆盖 ---------- */
.page-about .about-partner__grid {
  display: grid;
  grid-template-columns: minmax(0, 1fr);
  gap: clamp(24px, 4vw, 48px);
}

.page-about .about-partner__media {
  margin: 0;
}

.page-about .about-partner__media img {
  display: block;
  width: 100%;
  height: auto;
  aspect-ratio: 3 / 2;
  object-fit: cover;
}

.page-about .about-partner__text p {
  max-width: 34em;
  margin: 0 0 1em;
  font-size: 16px;
  line-height: 1.78;
  color: var(--steel-400);
}

.page-about .about-figures {
  display: grid;
  grid-template-columns: repeat(2, minmax(0, 1fr));
  gap: 18px 20px;
  margin: clamp(24px, 3vw, 32px) 0 0;
  padding: clamp(18px, 2.6vw, 26px) 0 0;
  list-style: none;
  border-top: 1px solid var(--ink-700);
}

.page-about .about-figures strong {
  display: block;
  font-family: var(--font-mono);
  font-size: clamp(24px, 3.4vw, 38px);
  font-weight: 700;
  line-height: 1;
  letter-spacing: -0.02em;
  color: var(--mist-100);
}

.page-about .about-figures small {
  margin-left: 3px;
  font-family: var(--font-body);
  font-size: 12px;
  font-weight: 400;
  color: var(--steel-400);
}

.page-about .about-figures span {
  display: block;
  margin-top: 8px;
  font-size: 13px;
  line-height: 1.5;
  color: var(--steel-400);
}

/* ---------- 后续入口 ---------- */
.page-about .about-next__list {
  display: grid;
  grid-template-columns: minmax(0, 1fr);
  gap: 1px;
  margin: clamp(8px, 2vw, 16px) 0 0;
  padding: 0;
  list-style: none;
  background: var(--ink-700);
}

.page-about .about-next__link {
  display: flex;
  flex-direction: column;
  gap: 8px;
  padding: clamp(20px, 3vw, 28px);
  background: var(--ink-900);
  color: inherit;
  text-decoration: none;
  transition: background var(--dur) var(--ease), transform var(--dur) var(--ease);
}

.page-about .about-next__link b {
  font-family: var(--font-display);
  font-size: clamp(18px, 2.1vw, 22px);
  font-weight: 700;
  line-height: 1.25;
}

.page-about .about-next__link span {
  font-size: 14px;
  line-height: 1.65;
  color: var(--steel-400);
}

.page-about .about-next__link::after {
  content: "→";
  margin-top: 6px;
  font-family: var(--font-mono);
  font-size: 14px;
  color: var(--track);
}

.page-about .about-next__link:hover,
.page-about .about-next__link:focus-visible {
  background: var(--ink-800);
  transform: translateX(2px);
}

.page-about .about-next__link:focus-visible {
  outline: 2px solid var(--signal);
  outline-offset: -2px;
}

/* ---------- 断点 ---------- */
@media (min-width: 720px) {
  .page-about .about-hero__meta {
    grid-template-columns: repeat(4, minmax(0, 1fr));
  }

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

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

@media (min-width: 760px) {
  .page-about .about-roles {
    grid-template-columns: repeat(3, minmax(0, 1fr));
  }
}

@media (min-width: 860px) {
  .page-about .about-lines__grid {
    grid-template-columns: repeat(3, minmax(0, 1fr));
  }
}

@media (min-width: 900px) {
  .page-about .about-split {
    grid-template-columns: minmax(0, 7fr) minmax(0, 4fr);
    align-items: start;
  }

  .page-about .about-flow__grid {
    grid-template-columns: minmax(0, 7fr) minmax(0, 4fr);
    align-items: start;
  }

  .page-about .about-partner__grid {
    grid-template-columns: minmax(0, 5fr) minmax(0, 6fr);
    align-items: center;
  }
}

@media (prefers-reduced-motion: reduce) {
  .page-about .about-steps summary,
  .page-about .about-role,
  .page-about .about-timeline__item::before,
  .page-about .about-next__link,
  .page-about .about-steps details {
    transition: none;
  }

  .page-about .about-steps summary:hover,
  .page-about .about-role:hover,
  .page-about .about-role:focus-within,
  .page-about .about-next__link:hover,
  .page-about .about-next__link:focus-visible {
    transform: none;
  }
}