.page-about {
  --about-cut: 18px;
  --about-gap: clamp(18px, 3.4vw, 36px);
  background:
    radial-gradient(110% 70% at 88% -8%, rgba(30, 91, 255, 0.2), transparent 62%),
    radial-gradient(80% 55% at -8% 102%, rgba(255, 106, 26, 0.12), transparent 60%),
    var(--void);
  color: var(--mist);
  font-family: var(--font-body);
}

.page-about *,
.page-about *::before,
.page-about *::after {
  box-sizing: border-box;
}

.page-about img {
  display: block;
  max-width: 100%;
  height: auto;
}

.page-about .about-crumb {
  padding-top: clamp(14px, 2.4vw, 26px);
}

.page-about .about-bignum {
  margin: 0 0 8px;
  font-family: var(--font-mono);
  font-size: clamp(44px, 8vw, 86px);
  line-height: 0.9;
  letter-spacing: -0.04em;
  color: rgba(34, 245, 212, 0.16);
  -webkit-text-stroke: 1px rgba(34, 245, 212, 0.55);
}

.page-about .about-h2 {
  margin: 12px 0 0;
  font-family: var(--font-display);
  font-weight: 800;
  font-size: clamp(24px, 3.6vw, 38px);
  line-height: 1.18;
  letter-spacing: -0.015em;
  color: var(--white);
}

.page-about .about-lede {
  margin: 16px 0 0;
  font-size: clamp(15px, 1.6vw, 16.5px);
  line-height: 1.78;
  color: var(--mist);
  max-width: 40em;
}

.page-about .about-section {
  position: relative;
  padding: clamp(38px, 6vw, 80px) 0;
}

/* 首屏 */
.page-about .about-hero {
  position: relative;
  padding: clamp(18px, 3vw, 30px) 0 clamp(38px, 6vw, 72px);
}

.page-about .about-hero__bg {
  position: absolute;
  inset: 0;
  z-index: 0;
  overflow: hidden;
  pointer-events: none;
}

.page-about .about-hero__bg img {
  width: 100%;
  height: 100%;
  object-fit: cover;
  opacity: 0.3;
}

.page-about .about-hero__bg::before {
  content: "";
  position: absolute;
  inset: 0;
  background: linear-gradient(105deg, var(--void) 22%, rgba(7, 11, 18, 0.78) 55%, rgba(7, 11, 18, 0.42) 100%);
}

.page-about .about-hero__bg::after {
  content: "";
  position: absolute;
  inset: 0;
  background-image:
    linear-gradient(rgba(42, 59, 85, 0.32) 1px, transparent 1px),
    linear-gradient(90deg, rgba(42, 59, 85, 0.32) 1px, transparent 1px);
  background-size: 64px 64px;
  opacity: 0.5;
}

.page-about .about-hero__grid {
  position: relative;
  z-index: 1;
  display: grid;
  gap: clamp(24px, 4vw, 44px);
  grid-template-columns: minmax(0, 1fr);
}

.page-about .about-hero h1 {
  margin: 14px 0 0;
  font-family: var(--font-display);
  font-weight: 900;
  font-size: clamp(30px, 6.2vw, 58px);
  line-height: 1.1;
  letter-spacing: -0.02em;
  color: var(--white);
  max-width: 16em;
}

.page-about .about-hero__lede {
  margin: 18px 0 0;
  font-size: clamp(15px, 1.6vw, 17px);
  line-height: 1.8;
  color: var(--mist);
  max-width: 34em;
}

.page-about .about-hero__acts,
.page-about .about-contact__acts {
  display: flex;
  flex-wrap: wrap;
  gap: 12px;
  margin-top: 26px;
}

.page-about .about-hero__card {
  position: relative;
  padding: clamp(18px, 2.6vw, 26px);
  background: linear-gradient(160deg, rgba(16, 26, 43, 0.95), rgba(12, 21, 34, 0.9));
  border: 1px solid var(--line);
  clip-path: polygon(0 0, 100% 0, 100% calc(100% - var(--about-cut)), calc(100% - var(--about-cut)) 100%, 0 100%);
}

.page-about .about-hero__card::before {
  content: "";
  position: absolute;
  left: 0;
  top: 0;
  width: 64px;
  height: 3px;
  background: var(--orange);
}

.page-about .about-hero__card-title {
  margin: 0;
  font-family: var(--font-mono);
  font-size: 12px;
  letter-spacing: 0.14em;
  color: var(--cyan);
}

.page-about .about-facts {
  margin: 18px 0 0;
  padding: 0;
  display: grid;
  gap: 12px;
}

.page-about .about-facts__row {
  display: flex;
  align-items: baseline;
  justify-content: space-between;
  gap: 14px;
  padding-bottom: 10px;
  border-bottom: 1px dashed rgba(42, 59, 85, 0.9);
}

.page-about .about-facts dt {
  font-size: 13px;
  color: var(--mist);
}

.page-about .about-facts dd {
  margin: 0;
  font-family: var(--font-mono);
  font-size: 13px;
  letter-spacing: 0.04em;
  color: var(--white);
  white-space: nowrap;
}

.page-about .about-facts__num {
  margin-right: 2px;
  font-size: 22px;
  color: var(--orange);
}

.page-about .about-hero__card-note {
  margin: 18px 0 0;
  font-size: 13px;
  line-height: 1.7;
  color: var(--mist);
}

/* 分屏结构 */
.page-about .about-split {
  display: grid;
  gap: clamp(22px, 4vw, 48px);
  grid-template-columns: minmax(0, 1fr);
}

.page-about .about-aside {
  margin: 14px 0 0;
  font-size: 14px;
  line-height: 1.75;
  color: var(--mist);
  max-width: 26em;
}

.page-about .about-body p {
  margin: 0 0 16px;
  font-size: clamp(15px, 1.6vw, 16.5px);
  line-height: 1.82;
  color: var(--mist);
  max-width: 38em;
}

.page-about .about-points {
  list-style: none;
  margin: 24px 0 0;
  padding: 0;
  display: grid;
  gap: 12px;
}

.page-about .about-points li {
  position: relative;
  padding: 14px 16px 14px 42px;
  background: rgba(16, 26, 43, 0.72);
  border-left: 2px solid var(--blue);
  font-size: 14px;
  line-height: 1.72;
  color: var(--mist);
}

.page-about .about-points li::before {
  content: "";
  position: absolute;
  left: 17px;
  top: 21px;
  width: 8px;
  height: 8px;
  background: var(--cyan);
  transform: rotate(45deg);
}

.page-about .about-points strong {
  display: block;
  margin-bottom: 3px;
  font-weight: 700;
  color: var(--white);
}

/* 内容线标签 */
.page-about .about-lines__head {
  display: grid;
  gap: 16px;
  grid-template-columns: minmax(0, 1fr);
}

.page-about .line-tabs {
  position: relative;
  margin-top: clamp(20px, 3vw, 34px);
}

.page-about .line-tabs__input {
  position: absolute;
  width: 1px;
  height: 1px;
  opacity: 0;
  pointer-events: none;
}

.page-about .line-tabs__labels {
  display: flex;
  flex-wrap: wrap;
  gap: 8px;
}

.page-about .line-tabs__labels label {
  flex: 1 1 auto;
  min-width: 132px;
  text-align: center;
  cursor: pointer;
  padding: 10px 16px;
  font-family: var(--font-mono);
  font-size: 12.5px;
  letter-spacing: 0.06em;
  color: var(--mist);
  background: var(--panel-2);
  border: 1px solid var(--line);
  clip-path: polygon(0 0, 100% 0, 100% calc(100% - 10px), calc(100% - 10px) 100%, 0 100%);
  transition: color 0.18s var(--ease), background 0.18s var(--ease), border-color 0.18s var(--ease);
}

.page-about .line-tabs__labels label:hover {
  color: var(--white);
  border-color: var(--blue);
}

.page-about #about-line-1:checked ~ .line-tabs__labels label[for="about-line-1"],
.page-about #about-line-2:checked ~ .line-tabs__labels label[for="about-line-2"],
.page-about #about-line-3:checked ~ .line-tabs__labels label[for="about-line-3"],
.page-about #about-line-4:checked ~ .line-tabs__labels label[for="about-line-4"] {
  background: var(--blue);
  border-color: var(--blue);
  color: var(--white);
}

.page-about .line-tabs__input:focus-visible ~ .line-tabs__labels label {
  outline: 2px solid var(--cyan);
  outline-offset: 2px;
}

.page-about .line-tabs__panels {
  margin-top: clamp(18px, 2.6vw, 26px);
}

.page-about .line-tabs__panel {
  display: none;
}

.page-about #about-line-1:checked ~ .line-tabs__panels > .line-tabs__panel:nth-child(1),
.page-about #about-line-2:checked ~ .line-tabs__panels > .line-tabs__panel:nth-child(2),
.page-about #about-line-3:checked ~ .line-tabs__panels > .line-tabs__panel:nth-child(3),
.page-about #about-line-4:checked ~ .line-tabs__panels > .line-tabs__panel:nth-child(4) {
  display: block;
}

.page-about .line-panel {
  padding: clamp(18px, 3vw, 30px);
  background: linear-gradient(150deg, rgba(16, 26, 43, 0.96), rgba(12, 21, 34, 0.9));
  border: 1px solid var(--line);
  clip-path: polygon(0 0, calc(100% - var(--about-cut)) 0, 100% var(--about-cut), 100% 100%, 0 100%);
}

.page-about .line-panel__meta {
  margin: 0;
  font-family: var(--font-mono);
  font-size: 11.5px;
  letter-spacing: 0.12em;
  color: var(--cyan);
}

.page-about .line-panel h3 {
  margin: 10px 0 0;
  font-family: var(--font-display);
  font-weight: 800;
  font-size: clamp(18px, 2.2vw, 23px);
  line-height: 1.3;
  color: var(--white);
}

.page-about .line-panel p {
  margin: 12px 0 0;
  font-size: 14.5px;
  line-height: 1.8;
  color: var(--mist);
  max-width: 42em;
}

.page-about .about-inline-link {
  display: inline-flex;
  align-items: center;
  gap: 8px;
  margin-top: 16px;
  padding-bottom: 3px;
  font-family: var(--font-mono);
  font-size: 12.5px;
  letter-spacing: 0.06em;
  color: var(--orange);
  text-decoration: none;
  border-bottom: 1px solid rgba(255, 106, 26, 0.55);
}

.page-about .about-inline-link:hover {
  color: var(--glow);
  border-color: var(--glow);
}

/* 会员服务 */
.page-about .about-member__grid {
  display: grid;
  gap: clamp(22px, 4vw, 44px);
  grid-template-columns: minmax(0, 1fr);
  align-items: center;
}

.page-about .about-member__figure {
  margin: 0;
  overflow: hidden;
  background: var(--panel-2);
  border: 1px solid var(--line);
  clip-path: polygon(0 0, 100% 0, 100% calc(100% - 24px), calc(100% - 24px) 100%, 0 100%);
}

.page-about .about-member__figure img {
  width: 100%;
  aspect-ratio: 10 / 7;
  object-fit: cover;
  opacity: 0.92;
}

.page-about .about-modules {
  list-style: none;
  margin: 24px 0 0;
  padding: 0;
  display: grid;
  gap: 12px;
}

.page-about .about-modules li {
  padding: 16px;
  background: rgba(16, 26, 43, 0.72);
  border: 1px solid var(--line);
  border-top: 2px solid rgba(30, 91, 255, 0.7);
}

.page-about .about-modules__no {
  font-family: var(--font-mono);
  font-size: 11px;
  letter-spacing: 0.1em;
  color: var(--cyan);
}

.page-about .about-modules strong {
  display: block;
  margin: 6px 0 4px;
  font-size: 15px;
  color: var(--white);
}

.page-about .about-modules p {
  margin: 0;
  font-size: 13.5px;
  line-height: 1.68;
  color: var(--mist);
}

.page-about .about-member__note {
  margin: 18px 0 0;
  padding-left: 14px;
  border-left: 2px solid var(--orange);
  font-size: 13.5px;
  line-height: 1.75;
  color: var(--mist);
}

/* 发展历程 */
.page-about .phase-list {
  list-style: none;
  margin: 0;
  padding: 0;
  position: relative;
}

.page-about .phase-list::before {
  content: "";
  position: absolute;
  left: 18px;
  top: 10px;
  bottom: 10px;
  width: 1px;
  background: linear-gradient(180deg, var(--blue), var(--cyan) 55%, var(--orange));
}

.page-about .phase {
  position: relative;
  padding-left: 48px;
  margin-bottom: 14px;
}

.page-about .phase::before {
  content: "";
  position: absolute;
  left: 12px;
  top: 22px;
  width: 13px;
  height: 13px;
  background: var(--void);
  border: 2px solid var(--cyan);
  transform: rotate(45deg);
  transition: border-color 0.18s var(--ease), background 0.18s var(--ease);
}

.page-about .phase:hover::before {
  border-color: var(--orange);
  background: var(--orange-soft);
}

.page-about .phase__detail {
  background: rgba(16, 26, 43, 0.78);
  border: 1px solid var(--line);
  border-left: 2px solid var(--blue);
}

.page-about .phase__detail[open] {
  background: rgba(16, 26, 43, 0.96);
  border-left-color: var(--orange);
}

.page-about .phase__summary {
  display: flex;
  align-items: center;
  gap: 12px;
  padding: 14px 16px;
  list-style: none;
  cursor: pointer;
}

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

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

.page-about .phase__name {
  font-family: var(--font-display);
  font-weight: 800;
  font-size: clamp(16px, 2vw, 19px);
  color: var(--white);
}

.page-about .phase__summary::after {
  content: "+";
  margin-left: auto;
  font-family: var(--font-mono);
  font-size: 16px;
  color: var(--orange);
}

.page-about .phase__detail[open] .phase__summary::after {
  content: "−";
}

.page-about .phase__body {
  margin: 0;
  padding: 0 16px 16px;
  font-size: 14px;
  line-height: 1.78;
  color: var(--mist);
}

/* 团队 */
.page-about .about-team__grid {
  display: grid;
  gap: clamp(20px, 3.4vw, 36px);
  grid-template-columns: minmax(0, 1fr);
  margin-top: clamp(20px, 3vw, 32px);
}

.page-about .about-team__figure {
  margin: 0;
  overflow: hidden;
  border: 1px solid var(--line);
  background: var(--panel-2);
  clip-path: polygon(0 0, 100% 0, 100% calc(100% - 24px), calc(100% - 24px) 100%, 0 100%);
}

.page-about .about-team__figure img {
  width: 100%;
  aspect-ratio: 3 / 2;
  object-fit: cover;
  opacity: 0.9;
}

.page-about .about-roles {
  list-style: none;
  margin: 0;
  padding: 0;
  display: grid;
  gap: 10px;
}

.page-about .about-roles li {
  display: grid;
  grid-template-columns: auto 1fr;
  gap: 4px 12px;
  padding: 14px 16px;
  background: var(--panel-2);
  border: 1px solid var(--line);
}

.page-about .about-roles__no {
  font-family: var(--font-mono);
  font-size: 11px;
  letter-spacing: 0.1em;
  color: var(--orange);
}

.page-about .about-roles strong {
  font-size: 15px;
  color: var(--white);
}

.page-about .about-roles p {
  grid-column: 2;
  margin: 0;
  font-size: 13.5px;
  line-height: 1.65;
  color: var(--mist);
}

.page-about .about-standards {
  display: grid;
  gap: 12px;
  margin-top: clamp(20px, 3vw, 32px);
}

.page-about .about-standards__item {
  padding: 18px 18px 20px;
  background: rgba(12, 21, 34, 0.82);
  border-top: 2px solid var(--blue);
}

.page-about .about-standards__item:nth-child(2) {
  border-top-color: var(--orange);
}

.page-about .about-standards__item:nth-child(3) {
  border-top-color: var(--cyan);
}

.page-about .about-standards__item h3 {
  margin: 0 0 8px;
  font-family: var(--font-display);
  font-weight: 800;
  font-size: 17px;
  color: var(--white);
}

.page-about .about-standards__item p {
  margin: 0;
  font-size: 13.5px;
  line-height: 1.7;
  color: var(--mist);
}

/* 联系 */
.page-about .about-contact {
  padding-bottom: clamp(52px, 8vw, 110px);
}

.page-about .about-contact__grid {
  display: grid;
  gap: clamp(22px, 4vw, 44px);
  grid-template-columns: minmax(0, 1fr);
}

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

.page-about .about-contact__list li {
  display: grid;
  gap: 5px;
  padding: 14px 0;
  border-bottom: 1px solid var(--line);
}

.page-about .about-contact__k {
  font-family: var(--font-mono);
  font-size: 11.5px;
  letter-spacing: 0.12em;
  color: var(--cyan);
}

.page-about .about-contact__v {
  font-size: 14.5px;
  line-height: 1.65;
  color: var(--white);
  overflow-wrap: anywhere;
}

/* 响应式 */
@media (min-width: 560px) {
  .page-about .about-modules {
    grid-template-columns: repeat(2, minmax(0, 1fr));
  }
}

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

  .page-about .about-lines__head {
    grid-template-columns: 7fr 5fr;
    align-items: end;
    gap: clamp(20px, 3vw, 40px);
  }

  .page-about .about-lines__head .about-lede {
    margin-top: 0;
  }
}

@media (min-width: 900px) {
  .page-about .about-hero__grid {
    grid-template-columns: 7fr 5fr;
    align-items: end;
  }

  .page-about .about-team__grid {
    grid-template-columns: 7fr 5fr;
    align-items: stretch;
  }

  .page-about .about-contact__grid {
    grid-template-columns: 7fr 5fr;
    align-items: start;
  }
}

@media (min-width: 960px) {
  .page-about .about-split {
    grid-template-columns: 5fr 7fr;
    align-items: start;
  }

  .page-about .about-member__grid {
    grid-template-columns: 5fr 7fr;
  }

  .page-about .about-sticky {
    position: sticky;
    top: 96px;
  }
}

@media (prefers-reduced-motion: reduce) {
  .page-about *,
  .page-about *::before,
  .page-about *::after {
    transition: none;
    animation: none;
  }
}