.page-about {
  --about-rail: 84px;
  --about-sticky: calc(var(--header-h) + 20px);
  display: block;
}

/* ---------- 首屏 ---------- */
.page-about .about-hero {
  position: relative;
  padding: calc(var(--header-h) + 44px) 0 0;
  background:
    radial-gradient(120% 90% at 86% -10%, rgba(184, 255, 60, 0.13), transparent 58%),
    radial-gradient(90% 70% at 4% 100%, rgba(58, 160, 255, 0.10), transparent 60%),
    linear-gradient(180deg, var(--ink) 0%, var(--ink-2) 100%);
  overflow: hidden;
}

.page-about .about-hero::before {
  content: "";
  position: absolute;
  inset: 0;
  background-image:
    repeating-linear-gradient(0deg, rgba(255, 255, 255, 0.035) 0 1px, transparent 1px 72px),
    repeating-linear-gradient(90deg, rgba(255, 255, 255, 0.035) 0 1px, transparent 1px 72px);
  pointer-events: none;
}

.page-about .about-hero__inner {
  position: relative;
  z-index: 1;
}

.page-about .breadcrumb {
  display: flex;
  flex-wrap: wrap;
  gap: 8px;
  align-items: center;
  margin-bottom: 22px;
  font-size: 13px;
  color: var(--fg-dim);
}

.page-about .breadcrumb__item {
  color: var(--fg-dim);
  text-decoration: none;
}

.page-about a.breadcrumb__item:hover {
  color: var(--lime);
}

.page-about .about-hero__title {
  margin: 14px 0 0;
  font-size: clamp(34px, 7.4vw, 88px);
  line-height: 1.02;
  letter-spacing: -0.02em;
  font-weight: 900;
  color: var(--fg);
  max-width: 18ch;
}

.page-about .about-hero__lede {
  margin-top: 24px;
  max-width: 42ch;
  color: var(--fg-dim);
  font-size: 16px;
  line-height: 1.75;
}

.page-about .about-figures {
  list-style: none;
  margin: 40px 0 0;
  padding: 0;
  display: grid;
  grid-template-columns: repeat(2, minmax(0, 1fr));
  gap: 1px;
  background: var(--line);
  border: 1px solid var(--line);
}

.page-about .about-figure {
  background: var(--ink);
  padding: 18px 16px;
  display: flex;
  flex-direction: column;
  gap: 6px;
}

.page-about .about-figure__num {
  font-size: clamp(26px, 4.6vw, 40px);
  font-weight: 700;
  color: var(--lime);
  letter-spacing: -0.02em;
  line-height: 1;
}

.page-about .about-figure__label {
  font-size: 13px;
  color: var(--fg-dim);
  letter-spacing: 0.04em;
}

/* ---------- 章节索引 ---------- */
.page-about .about-index {
  display: grid;
  grid-template-columns: 1fr;
  gap: 1px;
  background: var(--line);
  margin-top: 48px;
  border-top: 1px solid var(--line);
}

.page-about .about-index__item {
  display: flex;
  align-items: baseline;
  gap: 14px;
  padding: 16px 16px;
  background: var(--ink);
  color: var(--fg);
  text-decoration: none;
  transition: background 0.24s var(--ease), color 0.24s var(--ease);
}

.page-about .about-index__num {
  font-size: 13px;
  color: var(--fg-dim);
  transition: color 0.24s var(--ease);
}

.page-about .about-index__text {
  font-size: 15px;
  line-height: 1.5;
}

.page-about .about-index__item:hover,
.page-about .about-index__item:focus-visible {
  background: var(--ink-3);
}

.page-about .about-index__item:hover .about-index__num,
.page-about .about-index__item.is-current .about-index__num {
  color: var(--lime);
}

.page-about .about-index__item.is-current {
  background: var(--ink-3);
}

/* ---------- 通用区块 ---------- */
.page-about .about-block {
  padding-top: 72px;
  padding-bottom: 72px;
  border-top: 1px solid var(--line);
}

.page-about .about-block--alt {
  background: var(--ink-2);
}

.page-about .about-head {
  display: flex;
  flex-direction: column;
  gap: 10px;
  margin-bottom: 36px;
}

.page-about .about-head .section-num {
  color: var(--lime);
}

.page-about .about-head .h2 {
  max-width: 22ch;
}

.page-about .about-head__lede {
  max-width: 46ch;
  color: var(--fg-dim);
}

.page-about .about-split {
  display: grid;
  grid-template-columns: 1fr;
  gap: 36px;
}

.page-about .about-split__main p + p {
  margin-top: 18px;
}

/* ---------- 角色列表 ---------- */
.page-about .about-role-list {
  list-style: none;
  margin: 18px 0 0;
  padding: 0;
  display: grid;
  gap: 1px;
  background: var(--line);
  border: 1px solid var(--line);
}

.page-about .about-role {
  background: var(--ink);
  padding: 16px;
  display: flex;
  flex-direction: column;
  gap: 8px;
}

.page-about .about-role__tag {
  align-self: flex-start;
  font-size: 12px;
  letter-spacing: 0.08em;
  color: var(--lime);
  border: 1px solid rgba(184, 255, 60, 0.4);
  padding: 3px 8px;
  border-radius: var(--radius);
}

.page-about .about-role p {
  margin: 0;
  font-size: 14px;
  line-height: 1.7;
  color: var(--fg-dim);
}

/* ---------- 图片 ---------- */
.page-about .about-media {
  margin: 0 0 40px;
  border: 1px solid var(--line);
  background: var(--ink-3);
}

.page-about .about-media img,
.page-about .tl-media img,
.page-about .check-figure img {
  display: block;
  width: 100%;
  max-width: 100%;
  height: auto;
  object-fit: cover;
  filter: saturate(0.86) contrast(1.06);
}

.page-about .about-media .media__cap,
.page-about .tl-media .media__cap,
.page-about .check-figure .media__cap {
  display: block;
  padding: 10px 14px;
  font-size: 12px;
  line-height: 1.6;
  color: var(--fg-dim);
  border-top: 1px solid var(--line);
}

/* ---------- 三条线面板 ---------- */
.page-about .line-panels {
  display: grid;
  grid-template-columns: 1fr;
  gap: 18px;
}

.page-about .line-panel {
  position: relative;
  padding: 24px 20px 26px;
  border: 1px solid var(--line);
  border-radius: var(--radius);
  background: var(--glass);
  backdrop-filter: blur(6px);
  transition: transform 0.24s var(--ease), border-color 0.24s var(--ease);
}

.page-about .line-panel::after {
  content: "";
  position: absolute;
  left: 20px;
  right: 20px;
  top: 0;
  height: 2px;
  background: var(--lime);
  opacity: 0.35;
  transition: opacity 0.24s var(--ease);
}

.page-about .line-panel:hover {
  transform: translateY(-2px);
  border-color: rgba(184, 255, 60, 0.42);
}

.page-about .line-panel:hover::after {
  opacity: 1;
}

.page-about .line-panel__num {
  display: block;
  font-size: 12px;
  letter-spacing: 0.12em;
  color: var(--fg-dim);
  margin-bottom: 12px;
}

.page-about .line-panel .h3 {
  margin: 0 0 12px;
  color: var(--fg);
}

.page-about .line-panel > p {
  margin: 0;
  font-size: 15px;
  line-height: 1.75;
  color: var(--fg-dim);
}

.page-about .line-panel__list {
  list-style: none;
  margin: 18px 0 0;
  padding: 16px 0 0;
  border-top: 1px dashed var(--line);
  display: grid;
  gap: 10px;
}

.page-about .line-panel__list li {
  position: relative;
  padding-left: 18px;
  font-size: 13px;
  line-height: 1.6;
  color: var(--fg-dim);
}

.page-about .line-panel__list li::before {
  content: "";
  position: absolute;
  left: 0;
  top: 8px;
  width: 8px;
  height: 2px;
  background: var(--lime-deep);
}

/* ---------- 时间轴 ---------- */
.page-about .about-timeline {
  position: relative;
}

.page-about .tl-list {
  list-style: none;
  margin: 0;
  padding: 0;
  display: grid;
  gap: 34px;
}

.page-about .tl-item {
  display: grid;
  grid-template-columns: 1fr;
  gap: 12px;
  position: relative;
  padding-left: 18px;
}

.page-about .tl-item::before {
  content: "";
  position: absolute;
  left: 0;
  top: 6px;
  bottom: -34px;
  width: 2px;
  background: linear-gradient(180deg, var(--line), transparent);
}

.page-about .tl-item:last-child::before {
  display: none;
}

.page-about .tl-year {
  font-size: 20px;
  font-weight: 700;
  color: var(--lime);
  letter-spacing: 0.02em;
}

.page-about .tl-body .h3 {
  margin: 0 0 10px;
}

.page-about .tl-media {
  margin: 20px 0 0;
  border: 1px solid var(--line);
  background: var(--ink-3);
  max-width: 420px;
}

/* ---------- 三层校验 ---------- */
.page-about .about-check {
  display: grid;
  grid-template-columns: 1fr;
  gap: 32px;
}

.page-about .check-rings {
  display: flex;
  flex-direction: column;
  align-items: center;
  gap: 12px;
}

.page-about .check-rings__svg {
  width: min(240px, 68vw);
  height: auto;
  overflow: visible;
}

.page-about .ring {
  fill: none;
  stroke: var(--line);
  stroke-width: 3;
  transition: stroke 0.24s var(--ease), stroke-width 0.24s var(--ease);
}

.page-about .ring--2 {
  stroke: rgba(58, 160, 255, 0.45);
}

.page-about .ring--3 {
  stroke: rgba(184, 255, 60, 0.45);
}

.page-about .ring-core {
  fill: var(--lime);
  stroke: none;
}

.page-about .check-rings__cap {
  font-size: 12px;
  letter-spacing: 0.16em;
  color: var(--fg-dim);
}

.page-about .about-check:has(#chk-1[aria-expanded="true"]) .ring--1,
.page-about .about-check:has(#chk-2[aria-expanded="true"]) .ring--2,
.page-about .about-check:has(#chk-3[aria-expanded="true"]) .ring--3 {
  stroke: var(--lime);
  stroke-width: 5;
}

.page-about .check-folds {
  display: grid;
  gap: 1px;
  background: var(--line);
  border: 1px solid var(--line);
}

.page-about .check-fold {
  background: var(--ink);
}

.page-about .check-fold .fold__head {
  width: 100%;
  display: flex;
  align-items: center;
  gap: 12px;
  padding: 16px;
  background: transparent;
  border: 0;
  color: var(--fg);
  text-align: left;
  cursor: pointer;
  font: inherit;
  transition: background 0.24s var(--ease);
}

.page-about .check-fold .fold__head:hover {
  background: var(--ink-3);
}

.page-about .check-fold .fold__index {
  font-size: 12px;
  color: var(--lime);
}

.page-about .check-fold .fold__title {
  flex: 1;
  font-size: 15px;
  font-weight: 700;
}

.page-about .check-fold .fold__body {
  padding: 0 16px 18px 16px;
}

.page-about .check-fold .fold__body > p {
  margin: 0;
  font-size: 14px;
  line-height: 1.8;
  color: var(--fg-dim);
}

.page-about .check-fold .fold__head[aria-expanded="false"] + .fold__body {
  display: none;
}

.page-about .check-figure {
  margin: 0;
  border: 1px solid var(--line);
  background: var(--ink-3);
}

/* ---------- 资质徽章条 ---------- */
.page-about .trust-strip {
  list-style: none;
  display: flex;
  gap: 12px;
  margin: 0 0 36px;
  padding: 4px 4px 14px;
  overflow-x: auto;
  -webkit-overflow-scrolling: touch;
  scrollbar-width: thin;
}

.page-about .trust-badge {
  flex: 0 0 auto;
  min-width: 216px;
  display: flex;
  flex-direction: column;
  gap: 10px;
  padding: 18px 16px;
  border: 1px solid var(--line);
  border-left: 3px solid var(--lime);
  border-radius: var(--radius);
  background: var(--glass);
  transition: transform 0.24s var(--ease), border-color 0.24s var(--ease);
}

.page-about .trust-badge:hover {
  transform: translateY(-2px);
  border-color: rgba(184, 255, 60, 0.42);
  border-left-color: var(--lime);
}

.page-about .trust-badge__idx {
  font-size: 12px;
  letter-spacing: 0.12em;
  color: var(--fg-dim);
}

.page-about .trust-badge__name {
  font-size: 15px;
  line-height: 1.6;
  color: var(--fg);
}

.page-about .trust-notes {
  display: grid;
  grid-template-columns: 1fr;
  gap: 28px;
}

.page-about .trust-note .h3 {
  margin: 0 0 12px;
}

/* ---------- 使命 ---------- */
.page-about .about-block--mission {
  background:
    radial-gradient(80% 100% at 100% 0%, rgba(184, 255, 60, 0.09), transparent 62%),
    var(--ink);
}

.page-about .mission-grid {
  display: grid;
  grid-template-columns: 1fr;
  gap: 28px;
}

.page-about .mission-lead {
  margin: 0;
  font-size: clamp(22px, 4vw, 32px);
  line-height: 1.4;
  color: var(--lime);
}

.page-about .mission-list {
  list-style: none;
  margin: 0;
  padding: 0;
  display: grid;
  gap: 1px;
  background: var(--line);
  border: 1px solid var(--line);
}

.page-about .mission-item {
  background: var(--ink-2);
  padding: 20px 18px;
  display: grid;
  gap: 8px;
}

.page-about .mission-item__num {
  font-size: 12px;
  letter-spacing: 0.12em;
  color: var(--fg-dim);
}

.page-about .mission-item .h3 {
  margin: 0;
}

.page-about .mission-item p {
  margin: 0;
  font-size: 14px;
  line-height: 1.75;
  color: var(--fg-dim);
}

/* ---------- 收尾横条 ---------- */
.page-about .about-cta {
  border-top: 2px solid var(--lime);
  background: linear-gradient(100deg, rgba(184, 255, 60, 0.10), transparent 58%), var(--ink-2);
  padding: 44px 0 52px;
}

.page-about .about-cta__inner {
  display: grid;
  gap: 24px;
}

.page-about .about-cta__lead {
  margin: 0;
  font-size: clamp(22px, 4vw, 30px);
  font-weight: 800;
  letter-spacing: -0.01em;
  color: var(--fg);
}

.page-about .about-cta__sub {
  margin: 12px 0 0;
  max-width: 46ch;
  font-size: 15px;
  line-height: 1.75;
  color: var(--fg-dim);
}

.page-about .about-cta__actions {
  display: flex;
  flex-wrap: wrap;
  gap: 12px;
}

/* ---------- 响应式 ---------- */
@media (min-width: 720px) {
  .page-about .about-hero {
    padding-top: calc(var(--header-h) + 74px);
  }

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

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

  .page-about .about-split {
    grid-template-columns: minmax(0, 1.35fr) minmax(0, 1fr);
    gap: 48px;
    align-items: start;
  }

  .page-about .about-role-list {
    margin-top: 0;
  }

  .page-about .tl-item {
    grid-template-columns: var(--about-rail) minmax(0, 1fr);
    gap: 28px;
    padding-left: 0;
  }

  .page-about .tl-item::before {
    left: calc(var(--about-rail) + 8px);
  }

  .page-about .tl-year {
    position: sticky;
    top: var(--about-sticky);
    font-size: 22px;
  }

  .page-about .trust-notes {
    grid-template-columns: repeat(2, minmax(0, 1fr));
    gap: 40px;
  }

  .page-about .mission-grid {
    grid-template-columns: minmax(0, 0.55fr) minmax(0, 1.45fr);
    gap: 40px;
    align-items: start;
  }

  .page-about .about-cta__inner {
    grid-template-columns: minmax(0, 1fr) auto;
    align-items: center;
    gap: 32px;
  }

  .page-about .about-cta__actions {
    justify-content: flex-end;
  }
}

@media (min-width: 980px) {
  .page-about .about-block {
    padding-top: 92px;
    padding-bottom: 92px;
  }

  .page-about .line-panels {
    grid-template-columns: 1.1fr 0.98fr 0.86fr;
    gap: 20px;
    align-items: start;
  }

  .page-about .line-panel--a {
    margin-top: 0;
  }

  .page-about .line-panel--b {
    margin-top: 52px;
  }

  .page-about .line-panel--c {
    margin-top: 104px;
  }

  .page-about .about-check {
    grid-template-columns: 260px minmax(0, 1fr) 260px;
    gap: 36px;
    align-items: start;
  }

  .page-about .check-rings {
    position: sticky;
    top: var(--about-sticky);
  }

  .page-about .check-figure {
    align-self: start;
  }
}

@media (min-width: 1200px) {
  .page-about .about-hero__title {
    max-width: 16ch;
  }

  .page-about .about-media {
    margin-bottom: 52px;
  }
}