/* ================= page: about ================= */
.page-about {
  position: relative;
  display: block;
  background: var(--ink);
  color: var(--paper);
  font-family: var(--font-body);
  font-size: 16px;
  line-height: 1.75;
  padding-top: calc(var(--header-h, 68px) + 16px);
  padding-bottom: 64px;
  overflow-x: clip;
}

.page-about h1,
.page-about h2,
.page-about h3 {
  font-family: var(--font-display);
  letter-spacing: -0.01em;
}

.page-about h1 {
  font-size: clamp(2.1rem, 6.4vw, 3.3rem);
  font-weight: 900;
  line-height: 1.08;
  letter-spacing: -0.02em;
  margin: 0.18em 0 0.45em;
}

.page-about h2 {
  font-size: clamp(1.45rem, 3.6vw, 1.62rem);
  font-weight: 800;
  line-height: 1.32;
  margin: 0 0 12px;
}

.page-about h3 {
  font-size: 1.15rem;
  font-weight: 700;
  line-height: 1.42;
  margin: 0 0 6px;
}

.page-about p {
  margin: 0 0 1.2em;
}

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

.page-about .lead {
  font-size: 1.0625rem;
  line-height: 1.75;
  color: var(--mute);
  max-width: 36em;
}

.page-about .tnum {
  font-variant-numeric: tabular-nums;
}

.page-about .eyebrow {
  font-family: var(--font-mono);
  font-size: 12px;
  letter-spacing: 0.1em;
  text-transform: uppercase;
  color: var(--cyan);
  margin: 0 0 6px;
}

.page-about :is(.about-audience, .about-flow-section, .about-lines, .about-seasons, .about-source, .about-promise) {
  padding-block: 52px;
}

/* ---------- 滚动进度刻度 ---------- */
.page-about .about-progress {
  display: none;
}

/* ---------- 首屏 ---------- */
.page-about .about-hero__grid {
  display: grid;
  grid-template-columns: minmax(0, 1fr);
  gap: 28px;
  padding-block: 20px 8px;
}

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

.page-about .about-hero__lede .breadcrumbs {
  margin-bottom: 20px;
}

.page-about .about-hero__actions {
  display: flex;
  flex-wrap: wrap;
  gap: 12px;
  margin: 26px 0 0;
}

.page-about .about-hero__stats {
  list-style: none;
  margin: 28px 0 0;
  padding: 20px 0 0;
  border-top: 1px solid var(--rule);
  display: grid;
  grid-template-columns: repeat(3, minmax(0, 1fr));
  gap: 14px;
}

.page-about .about-hero__stats .stat-num {
  display: block;
  font-family: var(--font-mono);
  font-size: 1.3rem;
  font-weight: 700;
  line-height: 1.2;
  color: var(--lime);
  font-variant-numeric: tabular-nums;
}

.page-about .about-hero__stats .stat-label {
  display: block;
  margin-top: 4px;
  font-size: 13px;
  line-height: 1.5;
  color: var(--mute);
}

.page-about .about-hero__media {
  margin: 0;
  overflow: hidden;
  border-radius: 0 28px 0 28px;
  background: var(--ink-2);
}

.page-about .about-hero__media img {
  display: block;
  width: 100%;
  height: auto;
  aspect-ratio: 16 / 9;
  object-fit: cover;
  filter: saturate(0.85) contrast(1.06);
}

.page-about .media-frame__cap {
  display: block;
  padding: 12px 16px 14px;
  font-size: 13px;
  line-height: 1.6;
  color: var(--mute);
  background: var(--ink-2);
}

/* ---------- 区块标题 ---------- */
.page-about .about-head {
  max-width: 46em;
  margin-bottom: 30px;
}

/* ---------- 三类使用者 ---------- */
.page-about .about-audience {
  background: var(--ink-2);
  border-radius: 0 44px 0 44px;
  margin-top: 24px;
}

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

.page-about .about-audience__item {
  display: grid;
  grid-template-columns: 44px minmax(0, 1fr);
  grid-template-areas:
    "idx title"
    "idx body";
  gap: 4px 16px;
  padding: 24px 0;
  border-bottom: 1px solid var(--rule);
}

.page-about .about-audience__item:last-child {
  border-bottom: 0;
  padding-bottom: 4px;
}

.page-about .about-idx {
  grid-area: idx;
  align-self: start;
  padding-top: 2px;
  font-family: var(--font-mono);
  font-size: 13px;
  font-weight: 700;
  letter-spacing: 0.06em;
  color: var(--cyan);
  font-variant-numeric: tabular-nums;
}

.page-about .about-audience__title {
  grid-area: title;
  margin: 0 0 8px;
}

.page-about .about-audience__body {
  grid-area: body;
  min-width: 0;
}

.page-about .about-audience__body p {
  color: var(--mute);
  font-size: 15px;
  max-width: 40em;
}

.page-about .about-todo {
  list-style: none;
  margin: 14px 0 0;
  padding: 0;
  display: grid;
  gap: 8px;
}

.page-about .about-todo li {
  position: relative;
  padding-left: 20px;
  font-size: 14px;
  line-height: 1.65;
  color: var(--paper);
}

.page-about .about-todo li::before {
  content: "";
  position: absolute;
  left: 0;
  top: 0.68em;
  width: 10px;
  height: 2px;
  background: var(--cyan);
}

/* ---------- 流转流程 ---------- */
.page-about .about-flow {
  list-style: none;
  margin: 0 0 0 8px;
  padding: 0;
  border-left: 2px solid var(--rule);
}

.page-about .about-flow__step {
  position: relative;
  padding: 0 0 28px 26px;
}

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

.page-about .about-flow__step::before {
  content: "";
  position: absolute;
  left: -8px;
  top: 9px;
  width: 10px;
  height: 10px;
  border-radius: 50%;
  background: var(--ink);
  border: 2px solid var(--mist);
  transition: background var(--speed) var(--ease), border-color var(--speed) var(--ease);
}

.page-about .about-flow__step:hover::before,
.page-about .about-flow__step:focus-within::before {
  background: var(--cyan);
  border-color: var(--cyan);
}

.page-about .about-flow__step h3 {
  color: var(--paper);
}

.page-about .about-flow__step p {
  color: var(--mute);
  font-size: 15px;
  max-width: 40em;
}

.page-about .about-flow__media {
  margin: 34px 0 0;
  overflow: hidden;
  border-radius: 24px 0 24px 0;
  background: var(--ink-2);
}

.page-about .about-flow__media img {
  display: block;
  width: 100%;
  height: auto;
  object-fit: cover;
  filter: saturate(0.9);
}

/* ---------- 四条工作线 ---------- */
.page-about .about-lines__grid {
  display: grid;
  grid-template-columns: minmax(0, 1fr);
  gap: 32px;
}

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

.page-about .about-lines__bar {
  display: flex;
  flex-wrap: wrap;
  gap: 8px;
  margin-bottom: 10px;
}

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

.page-about .about-lines__item {
  display: grid;
  grid-template-columns: 72px minmax(0, 1fr);
  grid-template-areas:
    "count name"
    "count desc";
  gap: 4px 16px;
  padding: 22px 0;
  border-bottom: 1px solid var(--rule);
  transition: opacity var(--speed) var(--ease), transform var(--speed) var(--ease);
}

.page-about .about-lines__item[hidden] {
  display: none;
}

.page-about .about-lines__count {
  grid-area: count;
  align-self: start;
  padding-top: 2px;
  font-family: var(--font-mono);
  font-size: 14px;
  font-weight: 700;
  color: var(--amber);
  font-variant-numeric: tabular-nums;
  letter-spacing: 0.02em;
}

.page-about .about-lines__name {
  grid-area: name;
  margin: 0;
}

.page-about .about-lines__desc {
  grid-area: desc;
  margin: 4px 0 0;
  font-size: 15px;
  line-height: 1.75;
  color: var(--mute);
  max-width: 42em;
}

.page-about .about-lines__media {
  margin: 0;
  overflow: hidden;
  border-radius: 28px 0 28px 0;
  background: var(--ink-2);
}

.page-about .about-lines__media img {
  display: block;
  width: 100%;
  height: auto;
  aspect-ratio: 3 / 4;
  object-fit: cover;
  filter: saturate(0.85) contrast(1.05);
}

/* ---------- 赛季版本时间轴 ---------- */
.page-about .about-seasons {
  background: var(--ink-2);
  border-radius: 44px 0 44px 0;
}

.page-about .about-seasons__grid {
  display: grid;
  grid-template-columns: minmax(0, 1fr);
  gap: 30px;
}

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

.page-about .about-seasons__side .muted {
  font-size: 15px;
  color: var(--mute);
  max-width: 34em;
}

.page-about .about-tl {
  list-style: none;
  margin: 0 0 0 6px;
  padding: 0;
  border-left: 2px solid var(--rule);
  min-width: 0;
}

.page-about .about-tl__item {
  position: relative;
  padding-left: 22px;
}

.page-about .about-tl__item::before {
  content: "";
  position: absolute;
  left: -8px;
  top: 20px;
  width: 10px;
  height: 10px;
  border-radius: 50%;
  background: var(--ink-2);
  border: 2px solid var(--cyan);
}

.page-about .about-tl__card {
  border: 0;
}

.page-about .about-tl__card > summary {
  list-style: none;
  cursor: pointer;
  display: grid;
  grid-template-columns: 56px minmax(0, 1fr);
  gap: 2px 14px;
  align-items: baseline;
  padding: 14px 0;
  border-bottom: 1px solid var(--rule);
}

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

.page-about .about-tl__ver {
  font-family: var(--font-mono);
  font-size: 13px;
  font-weight: 700;
  letter-spacing: 0.05em;
  color: var(--mute);
  font-variant-numeric: tabular-nums;
  transition: color var(--speed) var(--ease);
}

.page-about .about-tl__card[open] .about-tl__ver {
  color: var(--cyan);
}

.page-about .about-tl__sum {
  font-family: var(--font-display);
  font-size: 1.05rem;
  font-weight: 700;
  color: var(--paper);
  transition: color var(--speed) var(--ease);
}

.page-about .about-tl__card > summary:hover .about-tl__sum {
  color: var(--cyan);
}

.page-about .about-tl__panel {
  padding: 16px 0 22px;
}

.page-about .about-tl__panel p {
  margin: 0;
  font-size: 15px;
  line-height: 1.78;
  color: var(--mute);
  max-width: 42em;
}

/* ---------- 内容来源 ---------- */
.page-about .about-source {
  background: var(--ink-3);
  border-radius: 0 44px 0 44px;
}

.page-about .about-source__grid {
  display: grid;
  grid-template-columns: minmax(0, 1fr);
  gap: 28px;
}

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

.page-about .about-source__items {
  display: grid;
  grid-template-columns: minmax(0, 1fr);
  gap: 24px;
}

.page-about .about-source__item {
  padding-top: 20px;
  border-top: 1px solid var(--rule);
}

.page-about .about-source__num {
  display: block;
  font-family: var(--font-mono);
  font-size: 2.4rem;
  font-weight: 700;
  line-height: 1;
  color: var(--lime);
  font-variant-numeric: tabular-nums;
  margin-bottom: 12px;
}

.page-about .about-source__item p {
  font-size: 15px;
  line-height: 1.78;
  color: var(--mute);
  max-width: 34em;
}

/* ---------- 收束 ---------- */
.page-about .about-promise__list {
  list-style: none;
  margin: 26px 0 0;
  padding: 0;
  display: grid;
  grid-template-columns: minmax(0, 1fr);
  gap: 0;
  border-top: 1px solid var(--rule);
}

.page-about .about-promise__list > li {
  padding: 24px 0;
  border-bottom: 1px solid var(--rule);
}

.page-about .about-promise__list > li:last-child {
  border-bottom: 0;
}

.page-about .about-promise__list p {
  font-size: 15px;
  line-height: 1.78;
  color: var(--mute);
  max-width: 32em;
  margin-bottom: 16px;
}

.page-about .about-promise__foot {
  margin: 26px 0 0;
  font-size: 15px;
  color: var(--mute);
}

.page-about .about-promise__foot a {
  color: var(--cyan);
  text-decoration: none;
  border-bottom: 1px solid var(--cyan-deep);
}

.page-about .about-promise__foot a:hover {
  border-bottom-color: var(--cyan);
}

/* ---------- 通用图片保护 ---------- */
.page-about .media-frame img {
  max-width: 100%;
  height: auto;
}

/* ================= 媒体查询 ================= */
@media (min-width: 620px) {
  .page-about .about-source__items {
    grid-template-columns: repeat(2, minmax(0, 1fr));
    gap: 28px;
  }
}

@media (min-width: 900px) {
  .page-about {
    padding-bottom: 88px;
  }

  .page-about :is(.about-audience, .about-flow-section, .about-lines, .about-seasons, .about-source, .about-promise) {
    padding-block: 76px;
  }

  .page-about .about-hero__grid {
    grid-template-columns: 38fr 62fr;
    gap: 48px;
    align-items: end;
    padding-block: 40px 24px;
  }

  .page-about .about-hero__media {
    border-radius: 0 40px 0 40px;
  }

  .page-about .about-hero__stats {
    gap: 24px;
  }

  .page-about .about-hero__stats .stat-num {
    font-size: 1.5rem;
  }

  .page-about .about-audience__item {
    grid-template-columns: 64px minmax(0, 0.9fr) minmax(0, 1.5fr);
    grid-template-areas: "idx title body";
    gap: 0 28px;
    align-items: start;
    padding: 28px 0;
  }

  .page-about .about-audience__title {
    margin-bottom: 0;
  }

  .page-about .about-flow {
    display: grid;
    grid-template-columns: repeat(5, minmax(0, 1fr));
    gap: 0 22px;
    border-left: 0;
    border-top: 2px solid var(--rule);
    margin-left: 0;
  }

  .page-about .about-flow__step {
    padding: 28px 0 0;
  }

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

  .page-about .about-flow__step::before {
    left: 0;
    top: -8px;
    background: var(--ink);
  }

  .page-about .about-flow__step p {
    font-size: 14.5px;
  }

  .page-about .about-flow__media {
    margin-top: 46px;
    border-radius: 32px 0 32px 0;
  }

  .page-about .about-lines__grid {
    grid-template-columns: minmax(0, 1.6fr) minmax(0, 0.9fr);
    gap: 48px;
    align-items: start;
  }

  .page-about .about-seasons__grid {
    grid-template-columns: minmax(0, 0.42fr) minmax(0, 1fr);
    gap: 56px;
    align-items: start;
  }

  .page-about .about-source__grid {
    grid-template-columns: minmax(0, 0.9fr) minmax(0, 1.1fr);
    gap: 48px;
    align-items: start;
  }

  .page-about .about-source__items {
    grid-template-columns: repeat(2, minmax(0, 1fr));
    gap: 32px;
  }

  .page-about .about-promise__list {
    grid-template-columns: repeat(3, minmax(0, 1fr));
    gap: 0 32px;
    border-top: 0;
  }

  .page-about .about-promise__list > li {
    border-top: 1px solid var(--rule);
    border-bottom: 0;
    padding: 26px 0 0;
  }
}

@media (min-width: 1200px) {
  .page-about .about-progress {
    display: block;
    position: fixed;
    right: 18px;
    top: calc(var(--header-h, 68px) + 40px);
    bottom: 44px;
    width: 2px;
    background: var(--rule);
    z-index: 5;
    pointer-events: none;
  }

  .page-about .about-progress__fill {
    display: block;
    width: 100%;
    height: calc(var(--scroll-progress, 0) * 100%);
    background: var(--cyan);
    transition: height 140ms linear;
  }

  .page-about .about-seasons__grid {
    grid-template-columns: minmax(0, 0.32fr) minmax(0, 1fr);
    gap: 72px;
  }

  .page-about .about-lines__grid {
    grid-template-columns: minmax(0, 1.7fr) minmax(0, 0.8fr);
    gap: 64px;
  }
}

@media (prefers-reduced-motion: reduce) {
  .page-about .about-progress__fill,
  .page-about .about-tl__sum,
  .page-about .about-tl__ver,
  .page-about .about-flow__step::before,
  .page-about .about-lines__item {
    transition: none;
  }
}