.page-about {
  --about-warm-ink: #101725;
  --about-warm-text: #3b3225;
  --about-warm-dim: #7a6a52;
  --about-grid-line: rgba(138, 155, 176, 0.14);
  --about-paper-shadow: 0 20px 48px rgba(0, 0, 0, 0.34);
  color: var(--fb-white);
  overflow-x: hidden;
}

.page-about .fb-crumbs {
  padding-top: clamp(84px, 12vw, 132px);
}

.page-about a {
  overflow-wrap: anywhere;
}

/* ---------- 首屏 ---------- */
.page-about .about-hero {
  position: relative;
  padding: clamp(20px, 4vw, 40px) 0 clamp(34px, 6vw, 68px);
}

.page-about .about-hero::before {
  content: "";
  position: absolute;
  inset: -40px -10vw auto -10vw;
  height: 130%;
  background:
    radial-gradient(circle at 78% 6%, rgba(45, 226, 230, 0.16), transparent 52%),
    radial-gradient(circle at 8% 92%, rgba(255, 122, 26, 0.13), transparent 48%);
  pointer-events: none;
  z-index: 0;
}

.page-about .about-hero__inner {
  position: relative;
  z-index: 1;
  display: grid;
  gap: 14px;
  max-width: 980px;
}

.page-about .about-hero__title {
  margin: 0;
  font-size: clamp(38px, 8vw, 76px);
  line-height: 1.02;
  letter-spacing: -0.03em;
  font-weight: 800;
  text-wrap: balance;
}

.page-about .about-hero__lead {
  margin: 0;
  max-width: 64ch;
  font-size: clamp(15.5px, 2vw, 18px);
  line-height: 1.78;
  color: var(--fb-mist);
}

.page-about .about-hero__marks {
  list-style: none;
  display: flex;
  flex-wrap: wrap;
  gap: 10px;
  padding: 0;
  margin: 10px 0 0;
}

/* ---------- 章节骨架 ---------- */
.page-about .about-block {
  padding: clamp(38px, 6vw, 82px) 0;
  position: relative;
}

.page-about .about-chapter {
  display: grid;
  grid-template-columns: minmax(0, 1fr);
  gap: 18px;
}

.page-about .about-chapter__rail {
  display: flex;
  align-items: center;
  gap: 12px;
}

.page-about .about-chapter__no {
  font-family: var(--fb-font-mono);
  font-size: 13px;
  letter-spacing: 0.18em;
  color: var(--fb-cyan);
}

.page-about .about-chapter__band {
  flex: 1 1 auto;
  height: 2px;
  max-width: 120px;
  background: linear-gradient(90deg, var(--fb-cyan), rgba(45, 226, 230, 0));
}

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

/* ---------- 01 品牌起源 ---------- */
.page-about .about-origin__paper {
  padding: clamp(22px, 4vw, 46px);
  border-radius: var(--fb-radius);
  box-shadow: var(--about-paper-shadow);
  color: var(--about-warm-text);
}

.page-about .about-origin__paper .fb-section__title {
  color: var(--about-warm-ink);
}

.page-about .about-origin__paper .fb-kicker {
  color: var(--about-warm-dim);
}

.page-about .about-origin__paper p {
  color: var(--about-warm-text);
}

.page-about .about-origin__figure {
  margin: 26px 0;
}

.page-about .about-origin__figure .fb-figure__frame {
  display: block;
  border-radius: 10px;
  overflow: hidden;
  border: 1px solid rgba(16, 23, 37, 0.16);
}

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

.page-about .about-origin__figure img {
  aspect-ratio: 16 / 9;
}

.page-about .about-origin__figure .fb-figure__cap {
  color: var(--about-warm-dim);
}

.page-about .about-origin__quote {
  margin: 26px 0;
  padding: 18px 20px;
  border-left: 4px solid var(--fb-orange);
  background: rgba(255, 122, 26, 0.09);
  border-radius: 0 10px 10px 0;
}

.page-about .about-origin__quote p {
  margin: 0;
  font-size: clamp(16px, 2.2vw, 19px);
  line-height: 1.7;
  font-weight: 600;
  color: var(--about-warm-ink);
}

/* ---------- 02 工作方式 ---------- */
.page-about .about-flow {
  background:
    repeating-linear-gradient(135deg, var(--about-grid-line) 0 1px, transparent 1px 14px),
    linear-gradient(180deg, rgba(16, 23, 37, 0) 0%, rgba(16, 23, 37, 0.86) 45%, rgba(7, 11, 20, 0) 100%);
}

.page-about .about-flow__grid {
  display: grid;
  grid-template-columns: minmax(0, 1fr);
  gap: 16px;
  margin-top: 28px;
}

.page-about .about-flow__card {
  border-top: 3px solid var(--fb-cyan);
  display: flex;
  flex-direction: column;
}

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

.page-about .about-flow__card:nth-child(3) {
  border-top-color: var(--fb-amber);
}

.page-about .about-flow__phase {
  margin: 0 0 8px;
  font-family: var(--fb-font-mono);
  font-size: 12px;
  letter-spacing: 0.2em;
  color: var(--fb-mist);
}

.page-about .about-flow__list {
  list-style: none;
  margin: 16px 0 0;
  padding: 0;
  display: grid;
  gap: 9px;
}

.page-about .about-flow__list li {
  position: relative;
  padding-left: 16px;
  font-size: 14.5px;
  line-height: 1.62;
  color: var(--fb-mist);
}

.page-about .about-flow__list li::before {
  content: "";
  position: absolute;
  left: 0;
  top: 0.72em;
  width: 7px;
  height: 1px;
  background: currentColor;
  opacity: 0.7;
}

/* ---------- 03 团队 ---------- */
.page-about .about-team__grid {
  display: grid;
  grid-template-columns: minmax(0, 1fr);
  gap: 26px;
  margin-top: 26px;
}

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

.page-about .about-team__figure .fb-figure__frame {
  display: block;
  border-radius: var(--fb-radius);
  overflow: hidden;
  border: 1px solid var(--fb-line);
}

.page-about .about-team__figure img {
  aspect-ratio: 3 / 2;
}

.page-about .about-team__body p {
  margin: 0;
  line-height: 1.78;
  color: var(--fb-mist);
}

.page-about .about-team__roles {
  list-style: none;
  margin: 22px 0 0;
  padding: 0;
  display: grid;
  gap: 12px;
}

.page-about .about-team__role {
  display: grid;
  gap: 5px;
  padding: 14px 16px;
  background: var(--fb-ink);
  border-left: 3px solid var(--fb-cyan);
  border-radius: 0 10px 10px 0;
}

.page-about .about-team__role strong {
  font-size: 15px;
  letter-spacing: 0.02em;
}

.page-about .about-team__role span {
  font-size: 14.5px;
  line-height: 1.62;
  color: var(--fb-mist);
}

.page-about .about-team__body .fb-note {
  margin-top: 18px;
  color: var(--fb-mist);
}

/* ---------- 04 赛季迭代 ---------- */
.page-about .about-timeline {
  list-style: none;
  margin: 28px 0 0;
  padding: 0;
}

.page-about .about-timeline__item {
  position: relative;
  padding: 0 0 30px 28px;
  border-left: 1px solid var(--fb-line);
}

.page-about .about-timeline__item:last-child {
  border-left-color: transparent;
  padding-bottom: 0;
}

.page-about .about-timeline__dot {
  position: absolute;
  left: -5px;
  top: 6px;
  width: 9px;
  height: 9px;
  border-radius: 50%;
  background: var(--fb-cyan);
  box-shadow: 0 0 0 4px rgba(45, 226, 230, 0.14);
}

.page-about .about-timeline__item--now .about-timeline__dot {
  background: var(--fb-orange);
  box-shadow: 0 0 0 4px rgba(255, 122, 26, 0.16);
}

.page-about .about-timeline__era {
  margin: 0 0 6px;
  font-family: var(--fb-font-mono);
  font-size: 12px;
  letter-spacing: 0.16em;
  color: var(--fb-cyan);
}

.page-about .about-timeline__item--now .about-timeline__era {
  color: var(--fb-orange);
}

.page-about .about-timeline__title {
  margin: 0 0 8px;
  font-size: clamp(18px, 2.4vw, 22px);
  line-height: 1.3;
}

.page-about .about-timeline__text {
  margin: 0;
  max-width: 68ch;
  line-height: 1.72;
  color: var(--fb-mist);
}

.page-about .about-timeline__more {
  margin-top: 12px;
  border-left: 2px solid var(--fb-line-strong);
  padding-left: 12px;
}

.page-about .about-timeline__more summary {
  cursor: pointer;
  font-size: 13px;
  letter-spacing: 0.06em;
  color: var(--fb-cyan);
  list-style: none;
}

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

.page-about .about-timeline__more summary::before {
  content: "+ ";
  font-family: var(--fb-font-mono);
}

.page-about .about-timeline__more[open] summary::before {
  content: "– ";
}

.page-about .about-timeline__more p {
  margin: 8px 0 0;
  font-size: 14.5px;
  line-height: 1.7;
  color: var(--fb-mist);
}

.page-about .about-iter__figure {
  margin: 30px 0 0;
}

.page-about .about-iter__figure .fb-figure__frame {
  display: block;
  border-radius: var(--fb-radius);
  overflow: hidden;
  border: 1px solid var(--fb-line);
}

.page-about .about-iter__figure img {
  aspect-ratio: 16 / 9;
}

/* ---------- 05 校验与合作 ---------- */
.page-about .about-check__grid {
  display: grid;
  grid-template-columns: minmax(0, 1fr);
  gap: 28px;
  margin-top: 28px;
}

.page-about .about-check__flow-wrap {
  padding: 18px;
  background: var(--fb-ink);
  border: 1px solid var(--fb-line);
  border-radius: var(--fb-radius);
}

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

.page-about .about-check__steps {
  display: grid;
  gap: 10px;
}

.page-about .about-check__step {
  padding: 12px 14px;
  background: rgba(16, 23, 37, 0.78);
  border: 1px solid var(--fb-line);
  border-radius: 10px;
}

.page-about .about-check__step summary {
  cursor: pointer;
  font-size: 15px;
  font-weight: 600;
  color: var(--fb-white);
  list-style: none;
}

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

.page-about .about-check__step summary::after {
  content: "展开";
  float: right;
  font-family: var(--fb-font-mono);
  font-size: 11px;
  letter-spacing: 0.14em;
  color: var(--fb-cyan);
  font-weight: 400;
}

.page-about .about-check__step[open] summary::after {
  content: "收起";
}

.page-about .about-check__step p {
  margin: 10px 0 0;
  font-size: 14.5px;
  line-height: 1.72;
  color: var(--fb-mist);
}

.page-about .about-check__note {
  margin: 18px 0 0;
  line-height: 1.72;
}

.page-about .about-check__note a {
  color: var(--fb-cyan);
  text-decoration: none;
  border-bottom: 1px solid rgba(45, 226, 230, 0.4);
}

.page-about .about-partner {
  margin-top: 34px;
  padding: clamp(20px, 3.4vw, 34px);
  border-radius: var(--fb-radius);
  background:
    linear-gradient(135deg, rgba(45, 226, 230, 0.1), rgba(255, 122, 26, 0.1)),
    var(--fb-ink);
  border: 1px solid var(--fb-line-strong);
}

.page-about .about-partner__title {
  margin: 0 0 12px;
  font-size: clamp(19px, 2.6vw, 25px);
}

.page-about .about-partner__text {
  margin: 0;
  max-width: 74ch;
  line-height: 1.78;
  color: var(--fb-mist);
}

/* ---------- 结尾入口 ---------- */
.page-about .about-cta {
  padding: clamp(36px, 5vw, 72px) 0 clamp(52px, 8vw, 104px);
}

.page-about .about-cta__inner {
  display: grid;
  grid-template-columns: minmax(0, 1fr);
  gap: 22px;
  padding: clamp(22px, 4vw, 42px);
  background: var(--fb-ink);
  border-top: 3px solid var(--fb-orange);
  border-radius: var(--fb-radius);
  box-shadow: var(--fb-shadow);
}

.page-about .about-cta__title {
  margin: 0 0 10px;
  font-size: clamp(20px, 3vw, 30px);
}

.page-about .about-cta__text {
  margin: 0;
  max-width: 62ch;
  line-height: 1.74;
  color: var(--fb-mist);
}

.page-about .about-cta__links {
  display: flex;
  flex-wrap: wrap;
  gap: 10px;
}

/* ---------- 平板与桌面 ---------- */
@media (min-width: 760px) {
  .page-about .about-flow__grid {
    grid-template-columns: repeat(3, minmax(0, 1fr));
    gap: 18px;
  }

  .page-about .about-chapter {
    grid-template-columns: 78px minmax(0, 1fr);
    gap: 34px;
  }

  .page-about .about-chapter__rail {
    flex-direction: column;
    align-items: flex-start;
    padding-top: 8px;
  }

  .page-about .about-chapter__band {
    flex: 0 0 auto;
    width: 2px;
    max-width: none;
    height: 96px;
    background: linear-gradient(180deg, var(--fb-cyan), rgba(45, 226, 230, 0));
  }

  .page-about .about-cta__inner {
    grid-template-columns: minmax(0, 1.35fr) auto;
    align-items: center;
    gap: 30px;
  }

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

@media (min-width: 960px) {
  .page-about .about-team__grid {
    grid-template-columns: minmax(0, 1fr) minmax(0, 1.05fr);
    align-items: center;
    gap: 40px;
  }

  .page-about .about-check__grid {
    grid-template-columns: minmax(0, 1.08fr) minmax(0, 1fr);
    gap: 34px;
    align-items: start;
  }

  .page-about .about-timeline {
    margin-top: 34px;
  }

  .page-about .about-timeline__item {
    padding-left: 34px;
  }
}

@media (prefers-reduced-motion: reduce) {
  .page-about .about-timeline__dot {
    box-shadow: none;
  }
}