/* =========================================================
   page-about — 品牌历程
   ========================================================= */

.page-about {
  --node: var(--silver-dim);
  --rail-w: 0px;
  --rail-gap: 0px;
  --content-offset: 0px;

  position: relative;
  background: var(--void);
  color: var(--silver);
  overflow-x: clip;
  font-family: var(--font-body);
  line-height: 1.85;
}

.page-about .about-hero__kicker,
.page-about .about-chapter__eyebrow,
.page-about .stat__label,
.page-about .season-line__season,
.page-about .team-split__num,
.page-about .next-list__num {
  font-family: var(--font-mono);
}

/* ---------------- HERO ---------------- */

.page-about .about-hero {
  position: relative;
  padding-block: clamp(24px, 4vw, 48px) clamp(52px, 8vw, 104px);
  isolation: isolate;
}

.page-about .about-hero::before {
  content: "";
  position: absolute;
  top: -34%;
  right: -18%;
  width: min(880px, 96vw);
  height: min(720px, 78vw);
  background: radial-gradient(closest-side, rgba(255, 107, 44, 0.18), transparent 72%);
  z-index: -1;
  pointer-events: none;
}

.page-about .about-hero::after {
  content: "";
  position: absolute;
  left: 0;
  right: 0;
  bottom: 0;
  height: 1px;
  background: linear-gradient(90deg, transparent, var(--line-strong) 26%, transparent 94%);
  pointer-events: none;
}

.page-about .about-hero__grid {
  display: grid;
  grid-template-columns: 1fr;
  gap: clamp(30px, 5vw, 52px);
  margin-top: clamp(24px, 4vw, 48px);
}

.page-about .about-hero__kicker {
  margin: 0;
  font-size: 11.5px;
  letter-spacing: 0.2em;
  color: var(--silver-dim);
}

.page-about .about-hero__title {
  font-family: var(--font-display);
  font-size: clamp(34px, 7.2vw, 78px);
  line-height: 1.04;
  letter-spacing: -0.018em;
  font-weight: 800;
  color: var(--white);
  margin: 14px 0 22px;
}

.page-about .about-hero__intro {
  max-width: 58ch;
  margin: 0 0 30px;
  font-size: clamp(15px, 1.35vw, 17px);
  color: var(--silver);
}

.page-about .about-hero__stats {
  list-style: none;
  margin: 0;
  padding: 22px 0 0;
  display: grid;
  grid-template-columns: repeat(3, minmax(0, 1fr));
  gap: 16px;
  border-top: 1px solid var(--line);
}

.page-about .about-hero__stat {
  display: flex;
  flex-direction: column;
  gap: 6px;
  min-width: 0;
}

.page-about .about-hero__stat .num-xl {
  font-family: var(--font-mono);
  font-size: clamp(22px, 3.4vw, 38px);
  line-height: 1;
  letter-spacing: -0.03em;
  font-weight: 600;
  color: var(--white);
}

.page-about .about-hero__stat .num-xl.is-signal { color: var(--signal); }
.page-about .about-hero__stat .num-xl.is-mint { color: var(--mint); }

.page-about .stat__label {
  font-size: 11.5px;
  letter-spacing: 0.08em;
  color: var(--silver-dim);
  line-height: 1.5;
}

/* ---------------- CHAPTER SHELL ---------------- */

.page-about .about-chapter {
  position: relative;
  padding-block: clamp(42px, 6.5vw, 92px);
}

.page-about .about-chapter--timeline {
  background: linear-gradient(180deg, transparent, rgba(14, 26, 51, 0.7) 18%, rgba(14, 26, 51, 0.7) 82%, transparent);
}

.page-about .about-chapter__grid {
  display: grid;
  grid-template-columns: 1fr;
  gap: clamp(12px, 2.6vw, 24px);
}

.page-about .about-chapter__rail {
  display: flex;
  align-items: baseline;
  gap: 14px;
}

.page-about .chapter__index {
  display: block;
  font-family: var(--font-mono);
  font-size: clamp(26px, 4vw, 42px);
  line-height: 1;
  letter-spacing: -0.03em;
  color: rgba(138, 148, 166, 0.5);
  transition: color 0.4s ease;
}

.page-about [data-chapter-index].is-active {
  color: var(--signal);
}

.page-about .about-chapter__eyebrow {
  margin: 0;
  font-size: 11px;
  letter-spacing: 0.2em;
  text-transform: uppercase;
  color: var(--silver-dim);
  white-space: nowrap;
}

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

.page-about .about-chapter__body .t-title {
  font-family: var(--font-display);
  font-size: clamp(23px, 3.3vw, 39px);
  line-height: 1.16;
  letter-spacing: -0.012em;
  font-weight: 700;
  color: var(--white);
  margin: 4px 0 18px;
}

.page-about .about-chapter__body > p {
  margin: 0 0 16px;
  font-size: clamp(14.5px, 1.25vw, 16.5px);
  color: var(--silver);
  max-width: 68ch;
}

.page-about .about-chapter__cta {
  margin-top: clamp(20px, 3vw, 32px);
  font-size: 15px;
  color: var(--silver-dim);
}

.page-about .about-link {
  color: var(--signal-soft);
  text-decoration: none;
  border-bottom: 1px solid rgba(255, 178, 122, 0.38);
  transition: color 0.24s ease, border-color 0.24s ease;
}

.page-about .about-link:hover,
.page-about .about-link:focus-visible {
  color: var(--signal);
  border-bottom-color: var(--signal);
}

/* ---------------- MEDIA ---------------- */

.page-about .about-media {
  margin: clamp(26px, 4vw, 44px) 0 0;
  border: 1px solid var(--line);
  border-radius: var(--radius);
  overflow: hidden;
  background: var(--deep);
}

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

.page-about .about-media .media-frame__caption {
  padding: 12px 16px 14px;
  font-size: 12.5px;
  line-height: 1.65;
  color: var(--silver-dim);
  background: rgba(14, 26, 51, 0.85);
  border-top: 1px solid var(--line);
}

/* ---------------- 02 时间线 ---------------- */

.page-about .season-line {
  list-style: none;
  margin: clamp(30px, 4.5vw, 52px) 0 0;
  padding: 0;
  position: relative;
  display: grid;
  gap: clamp(16px, 2.6vw, 26px);
}

.page-about .season-line::before {
  content: "";
  position: absolute;
  left: 6px;
  top: 10px;
  bottom: 10px;
  width: 2px;
  border-radius: 2px;
  background: linear-gradient(
    180deg,
    rgba(201, 210, 224, 0.22) 0%,
    var(--mint-deep) 26%,
    var(--mint) 46%,
    var(--signal-soft) 72%,
    var(--signal) 100%
  );
}

.page-about .season-line__node {
  position: relative;
  padding-left: 38px;
  min-width: 0;
}

.page-about .season-line__dot {
  position: absolute;
  left: 0;
  top: 26px;
  width: 14px;
  height: 14px;
  border-radius: 50%;
  background: var(--void);
  border: 2px solid var(--node);
  box-shadow: 0 0 0 4px rgba(7, 14, 31, 0.92);
}

.page-about .season-line__node:nth-child(1) { --node: rgba(201, 210, 224, 0.48); }
.page-about .season-line__node:nth-child(2) { --node: #1B9E7C; }
.page-about .season-line__node:nth-child(3) { --node: #4FE0B5; }
.page-about .season-line__node:nth-child(4) { --node: #FFB27A; }
.page-about .season-line__node:nth-child(5) { --node: #FF8A4C; }
.page-about .season-line__node:nth-child(6) { --node: #FF6B2C; }

.page-about .season-line__card {
  padding: 20px 22px 22px;
  border: 1px solid var(--line);
  border-radius: var(--radius);
  background: var(--glass-bg);
  backdrop-filter: blur(8px);
  transition: border-color 0.3s ease, transform 0.3s ease, background 0.3s ease;
}

.page-about .season-line__node:hover .season-line__card,
.page-about .season-line__node:focus-within .season-line__card {
  border-color: var(--node);
  background: rgba(23, 40, 74, 0.78);
  transform: translateY(-3px);
}

.page-about .season-line__season {
  margin: 0;
  font-size: 12.5px;
  letter-spacing: 0.14em;
  color: var(--node);
}

.page-about .season-line__title {
  font-family: var(--font-display);
  font-size: clamp(18px, 1.9vw, 21px);
  line-height: 1.3;
  color: var(--white);
  margin: 8px 0 8px;
}

.page-about .season-line__card > p {
  margin: 0;
  font-size: 14.5px;
  line-height: 1.78;
  color: var(--silver-dim);
}

.page-about .season-line__facts {
  list-style: none;
  margin: 14px 0 0;
  padding: 12px 0 0;
  border-top: 1px dashed var(--line);
  display: flex;
  flex-wrap: wrap;
  gap: 8px 20px;
}

.page-about .season-line__facts li {
  font-family: var(--font-mono);
  font-size: 11.5px;
  letter-spacing: 0.06em;
  color: var(--silver-dim);
}

.page-about .season-line__facts b {
  color: var(--white);
  font-weight: 600;
  margin-left: 4px;
}

.page-about .about-chapter--timeline .about-media {
  margin-top: clamp(30px, 4.5vw, 52px);
}

/* ---------------- 03 团队 ---------------- */

.page-about .team-split {
  display: grid;
  grid-template-columns: 1fr;
  gap: 16px;
  margin: clamp(24px, 4vw, 40px) 0 0;
}

.page-about .team-split__item {
  position: relative;
  padding: 24px 22px 26px;
  border: 1px solid var(--line);
  border-radius: var(--radius);
  background: linear-gradient(180deg, rgba(23, 40, 74, 0.6), rgba(14, 26, 51, 0.5));
  transition: border-color 0.3s ease, transform 0.3s ease;
}

.page-about .team-split__item::before {
  content: "";
  position: absolute;
  top: -1px;
  left: 22px;
  width: 46px;
  height: 2px;
  background: var(--mint);
  opacity: 0.75;
}

.page-about .team-split__item:nth-child(2)::before { background: var(--signal-soft); }
.page-about .team-split__item:nth-child(3)::before { background: var(--silver-dim); }

.page-about .team-split__item:hover {
  border-color: var(--signal);
  transform: translateY(-4px);
}

.page-about .team-split__num {
  margin: 0;
  font-size: clamp(30px, 4.4vw, 44px);
  line-height: 1;
  letter-spacing: -0.04em;
  font-weight: 600;
  color: var(--mint);
}

.page-about .team-split__title {
  font-family: var(--font-display);
  font-size: 18px;
  line-height: 1.35;
  color: var(--white);
  margin: 12px 0 8px;
}

.page-about .team-split__item > p:last-child {
  margin: 0;
  font-size: 14.5px;
  line-height: 1.78;
  color: var(--silver-dim);
}

/* ---------------- 04 奖项战报演进 ---------------- */

.page-about .award-stages {
  list-style: none;
  margin: clamp(24px, 4vw, 40px) 0 0;
  padding: 0;
  counter-reset: award;
}

.page-about .award-stages__item {
  position: relative;
  counter-increment: award;
  padding: 22px 0 24px 58px;
  border-top: 1px solid var(--line);
}

.page-about .award-stages__item:last-child {
  border-bottom: 1px solid var(--line);
}

.page-about .award-stages__item::before {
  content: "0" counter(award);
  position: absolute;
  left: 0;
  top: 24px;
  font-family: var(--font-mono);
  font-size: 18px;
  letter-spacing: -0.02em;
  color: var(--signal-soft);
}

.page-about .award-stages__item::after {
  content: "";
  position: absolute;
  left: 40px;
  top: 22px;
  bottom: 22px;
  width: 1px;
  background: var(--line);
}

.page-about .award-stages__title {
  font-family: var(--font-display);
  font-size: 19px;
  line-height: 1.35;
  color: var(--white);
  margin: 0 0 6px;
}

.page-about .award-stages__item > p {
  margin: 0;
  font-size: 14.5px;
  line-height: 1.78;
  color: var(--silver-dim);
  max-width: 60ch;
}

/* ---------------- 05 共建 ---------------- */

.page-about .partner-cards {
  display: grid;
  grid-template-columns: 1fr;
  gap: 16px;
  margin: clamp(24px, 4vw, 40px) 0 0;
}

.page-about .partner-cards__item {
  position: relative;
  padding: 24px 22px 26px;
  border: 1px solid var(--line);
  border-radius: var(--radius);
  background: var(--glass-bg);
  backdrop-filter: blur(6px);
  transition: border-color 0.3s ease, background 0.3s ease;
}

.page-about .partner-cards__item:hover {
  border-color: var(--signal);
  background: rgba(23, 40, 74, 0.84);
}

.page-about .partner-cards__title {
  font-family: var(--font-display);
  font-size: 19px;
  line-height: 1.35;
  color: var(--white);
  margin: 14px 0 8px;
}

.page-about .partner-cards__item > p {
  margin: 0;
  font-size: 14.5px;
  line-height: 1.78;
  color: var(--silver-dim);
}

/* ---------------- 06 下一阶段 ---------------- */

.page-about .about-chapter--next::before {
  content: "";
  position: absolute;
  top: 0;
  left: 0;
  width: min(320px, 42vw);
  height: 3px;
  background: linear-gradient(90deg, var(--signal), transparent);
}

.page-about .next-list {
  list-style: none;
  margin: clamp(22px, 3.6vw, 38px) 0 0;
  padding: 0;
}

.page-about .next-list__item {
  display: grid;
  grid-template-columns: 48px minmax(0, 1fr);
  gap: 16px;
  padding: 20px 0 22px;
  border-top: 1px solid var(--line);
}

.page-about .next-list__item:last-child {
  border-bottom: 1px solid var(--line);
}

.page-about .next-list__num {
  font-size: clamp(20px, 2.4vw, 26px);
  line-height: 1;
  letter-spacing: -0.03em;
  color: var(--signal);
  padding-top: 2px;
}

.page-about .next-list__item h3 {
  font-family: var(--font-display);
  font-size: 18px;
  line-height: 1.35;
  color: var(--white);
  margin: 0 0 6px;
}

.page-about .next-list__item p {
  margin: 0;
  font-size: 14.5px;
  line-height: 1.78;
  color: var(--silver-dim);
  max-width: 62ch;
}

/* ---------------- 响应式 ---------------- */

@media (min-width: 640px) {
  .page-about .about-media img {
    max-height: 520px;
  }
}

@media (min-width: 900px) {
  .page-about {
    --rail-w: 128px;
    --rail-gap: clamp(32px, 6vw, 88px);
    --content-offset: calc(var(--rail-w) + var(--rail-gap));
  }

  .page-about .about-hero__grid {
    grid-template-columns: minmax(0, 1fr) minmax(230px, 300px);
    align-items: end;
    gap: clamp(36px, 6vw, 88px);
  }

  .page-about .about-hero__stats {
    grid-template-columns: 1fr;
    gap: 22px;
    padding: 0 0 0 26px;
    border-top: 0;
    border-left: 1px solid var(--line);
  }

  .page-about .about-chapter__grid {
    grid-template-columns: var(--rail-w) minmax(0, 1fr);
    gap: var(--rail-gap);
    align-items: start;
  }

  .page-about .about-chapter__rail {
    position: sticky;
    top: 132px;
    display: block;
  }

  .page-about .about-chapter__eyebrow {
    margin-top: 10px;
  }

  .page-about .season-line,
  .page-about .about-chapter--timeline .about-media {
    margin-left: var(--content-offset);
  }

  .page-about .season-line__node:nth-child(even) {
    margin-left: clamp(20px, 5vw, 72px);
  }

  .page-about .team-split {
    grid-template-columns: repeat(12, minmax(0, 1fr));
    column-gap: clamp(16px, 2.4vw, 26px);
    row-gap: 18px;
  }

  .page-about .team-split__item:nth-child(1) { grid-column: 1 / span 7; }
  .page-about .team-split__item:nth-child(2) { grid-column: 8 / span 5; }
  .page-about .team-split__item:nth-child(3) { grid-column: 3 / span 6; }

  .page-about .partner-cards {
    grid-template-columns: repeat(12, minmax(0, 1fr));
    column-gap: clamp(16px, 2.4vw, 26px);
    row-gap: 18px;
  }

  .page-about .partner-cards__item:nth-child(1) { grid-column: 1 / span 5; }
  .page-about .partner-cards__item:nth-child(2) { grid-column: 6 / span 7; }
  .page-about .partner-cards__item:nth-child(3) { grid-column: 3 / span 7; }

  .page-about .award-stages__item {
    padding-left: 72px;
  }

  .page-about .award-stages__item::after {
    left: 52px;
  }

  .page-about .about-media img {
    max-height: 620px;
  }
}

@media (min-width: 1200px) {
  .page-about .about-chapter__body > p {
    font-size: 16.5px;
  }
}

@media (prefers-reduced-motion: reduce) {
  .page-about .season-line__card,
  .page-about .team-split__item,
  .page-about .partner-cards__item,
  .page-about [data-chapter-index] {
    transition: none;
  }

  .page-about .season-line__node:hover .season-line__card,
  .page-about .season-line__node:focus-within .season-line__card,
  .page-about .team-split__item:hover {
    transform: none;
  }
}