/* ============================================================
   品牌沿革 /culture/
   左侧纵向节点轴 + 右侧叠层纸张卡片，由密到疏
   ============================================================ */

.page-about {
  --about-axis-w: 152px;
  --about-shell-gap: 40px;
  --about-lift: 7px;
}

/* ---------- 面包屑 ---------- */
.page-about .breadcrumb {
  padding-top: 18px;
  padding-bottom: 14px;
}

/* ---------- 首屏 ---------- */
.page-about .about-hero {
  position: relative;
  overflow: hidden;
  padding-bottom: 44px;
  background:
    linear-gradient(180deg, var(--abyss-950) 0%, var(--abyss-900) 58%, var(--abyss-950) 100%);
}

.page-about .about-hero::after {
  content: "";
  position: absolute;
  inset: 0;
  background-image:
    linear-gradient(var(--grid-line) 1px, transparent 1px),
    linear-gradient(90deg, var(--grid-line) 1px, transparent 1px);
  background-size: 52px 52px;
  -webkit-mask-image: linear-gradient(180deg, #000 0%, transparent 86%);
  mask-image: linear-gradient(180deg, #000 0%, transparent 86%);
  pointer-events: none;
}

.page-about .about-hero__slab {
  position: absolute;
  top: -14%;
  right: -22%;
  width: 78%;
  height: 76%;
  background: linear-gradient(158deg, rgba(53, 224, 214, 0.17), rgba(18, 167, 156, 0.02) 70%);
  clip-path: polygon(20% 0, 100% 0, 100% 100%, 0 76%);
  pointer-events: none;
}

.page-about .about-hero__glow {
  position: absolute;
  left: 6%;
  top: 10%;
  width: 340px;
  height: 340px;
  background: radial-gradient(circle, rgba(53, 224, 214, 0.13), transparent 68%);
  pointer-events: none;
}

.page-about .about-hero__inner {
  position: relative;
  z-index: 1;
  padding-top: 8px;
}

.page-about .about-hero__eyebrow {
  margin: 0;
  font-size: 11.5px;
  letter-spacing: 0.2em;
  text-transform: uppercase;
  color: var(--neon-400);
}

.page-about .about-hero__title {
  margin: 14px 0 0;
  max-width: 15ch;
  font-family: var(--font-display);
  font-weight: 800;
  font-size: clamp(30px, 7.6vw, 54px);
  line-height: 1.1;
  letter-spacing: -0.02em;
  color: var(--paper-50);
}

.page-about .about-hero__lead {
  margin: 20px 0 0;
  max-width: 60ch;
  color: rgba(243, 241, 234, 0.76);
}

.page-about .about-hero__stats {
  list-style: none;
  margin: 30px 0 0;
  padding: 20px 0 0;
  border-top: 1px solid var(--hair);
  display: grid;
  grid-template-columns: repeat(2, minmax(0, 1fr));
  gap: 20px 18px;
}

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

.page-about .about-hero__num {
  font-size: 30px;
  line-height: 1;
  color: var(--amber-400);
  font-variant-numeric: tabular-nums;
}

.page-about .about-hero__cap {
  font-size: 13px;
  line-height: 1.5;
  color: var(--stone-400);
}

.page-about .about-hero__figure {
  position: relative;
  z-index: 1;
  margin: 38px 0 0;
}

/* ---------- 主体：左轴 + 右流 ---------- */
.page-about .about-shell {
  display: grid;
  grid-template-columns: minmax(0, 1fr);
  gap: 28px;
  padding-top: 42px;
  padding-bottom: 64px;
}

/* ---------- 左侧节点轴 ---------- */
.page-about .about-axis {
  position: sticky;
  top: calc(var(--topbar-h) + 6px);
  z-index: 4;
  padding: 10px 0 12px;
  background: var(--abyss-950);
  border-bottom: 1px solid var(--hair);
}

.page-about .about-axis__caption {
  margin: 0 0 10px;
  font-size: 11px;
  letter-spacing: 0.2em;
  color: var(--stone-400);
}

.page-about .about-axis__list {
  list-style: none;
  margin: 0;
  padding: 0 0 2px;
  display: flex;
  gap: 6px;
  overflow-x: auto;
  scrollbar-width: none;
  -webkit-overflow-scrolling: touch;
}

.page-about .about-axis__list::-webkit-scrollbar {
  display: none;
}

.page-about .about-axis__node {
  display: inline-flex;
  align-items: baseline;
  gap: 7px;
  padding: 7px 11px;
  border: 1px solid var(--hair);
  color: var(--stone-400);
  font-size: 13px;
  line-height: 1.3;
  text-decoration: none;
  white-space: nowrap;
  transition: color 160ms var(--ease), border-color 160ms var(--ease);
}

.page-about .about-axis__idx {
  font-size: 11px;
  color: var(--neon-600);
  transition: color 160ms var(--ease);
}

.page-about .about-axis__node:hover,
.page-about .about-axis__node:focus-visible {
  color: var(--neon-400);
  border-color: var(--neon-line);
  outline: none;
}

.page-about .about-axis__node:hover .about-axis__idx,
.page-about .about-axis__node:focus-visible .about-axis__idx {
  color: var(--neon-400);
}

/* ---------- 右侧内容流 ---------- */
.page-about .about-stream {
  display: flex;
  flex-direction: column;
  gap: 34px;
  min-width: 0;
}

/* ---------- 阶段卡片（叠层纸张） ---------- */
.page-about .stage {
  position: relative;
  padding: 24px 20px 26px;
  border: 1px solid var(--hair);
  background: linear-gradient(155deg, var(--abyss-900) 0%, var(--abyss-700) 128%);
  box-shadow: 5px 5px 0 -1px var(--abyss-950), 5px 5px 0 0 var(--hair);
  scroll-margin-top: calc(var(--topbar-h) + 96px);
}

.page-about .stage--paper {
  background: var(--paper-50);
  border-color: rgba(11, 20, 24, 0.16);
  box-shadow: 5px 5px 0 -1px var(--abyss-950), 5px 5px 0 0 rgba(140, 154, 166, 0.34);
}

.page-about .stage__head {
  display: flex;
  align-items: flex-start;
  gap: 13px;
  padding-bottom: 14px;
  margin-bottom: 18px;
  border-bottom: 1px solid var(--hair);
}

.page-about .stage--paper .stage__head {
  border-bottom-color: rgba(11, 20, 24, 0.14);
}

.page-about .stage__code {
  flex: none;
  padding: 3px 7px;
  font-size: 12px;
  color: var(--neon-400);
  border: 1px solid var(--neon-line);
  font-variant-numeric: tabular-nums;
}

.page-about .stage--paper .stage__code {
  color: var(--ink-900);
  border-color: rgba(11, 20, 24, 0.26);
}

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

.page-about .stage__time {
  margin: 0 0 5px;
  font-size: 11px;
  letter-spacing: 0.16em;
  color: var(--stone-400);
}

.page-about .stage--paper .stage__time {
  color: rgba(11, 20, 24, 0.55);
}

.page-about .stage__title {
  margin: 0;
  font-family: var(--font-display);
  font-weight: 800;
  font-size: clamp(20px, 4.4vw, 26px);
  line-height: 1.3;
  letter-spacing: -0.01em;
  color: var(--paper-50);
}

.page-about .stage--paper .stage__title {
  color: var(--ink-900);
}

.page-about .stage__text {
  margin: 0 0 15px;
  max-width: 62ch;
  font-size: 16px;
  line-height: 1.78;
  color: rgba(243, 241, 234, 0.78);
}

.page-about .stage--paper .stage__text {
  color: rgba(11, 20, 24, 0.8);
}

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

.page-about .stage__figure {
  margin: 22px 0 0;
}

.page-about .text-link {
  color: var(--neon-600);
  text-decoration: underline;
  text-underline-offset: 3px;
  text-decoration-thickness: 1px;
}

.page-about .stage--paper .text-link {
  color: var(--clay-500);
  text-decoration-color: var(--clay-line);
}

.page-about .text-link:hover,
.page-about .text-link:focus-visible {
  color: var(--neon-400);
  outline: none;
}

/* ---------- 三层编号清单 ---------- */
.page-about .tier {
  margin: 20px 0 18px;
  padding: 16px 0 4px;
  border-top: 1px solid var(--hair);
  border-bottom: 1px solid var(--hair);
}

.page-about .tier__caption {
  margin: 0 0 12px;
  font-size: 11px;
  letter-spacing: 0.2em;
  color: var(--stone-400);
}

.page-about .tier__list {
  list-style: none;
  margin: 0;
  padding: 0;
}

.page-about .tier__item {
  display: flex;
  flex-direction: column;
  gap: 4px;
  padding: 10px 0 10px 14px;
  border-left: 2px solid var(--neon-600);
  margin-bottom: 8px;
}

.page-about .tier__key {
  font-size: 13px;
  letter-spacing: 0.06em;
  color: var(--neon-400);
}

.page-about .tier__desc {
  font-size: 14.5px;
  line-height: 1.6;
  color: var(--stone-400);
}

/* ---------- 可复制编号 ---------- */
.page-about .stage__codecopy {
  display: flex;
  flex-wrap: wrap;
  align-items: center;
  gap: 12px;
  margin: 0 0 20px;
}

.page-about .code-chip {
  font-family: var(--font-mono);
  font-size: 15px;
  font-weight: 500;
  letter-spacing: 0.08em;
  color: var(--amber-400);
  background: rgba(232, 176, 75, 0.08);
  border: 1px dashed var(--amber-line);
  padding: 8px 14px;
  cursor: pointer;
  transition: background 160ms var(--ease), border-color 160ms var(--ease);
}

.page-about .code-chip:hover,
.page-about .code-chip:focus-visible {
  background: rgba(232, 176, 75, 0.18);
  border-color: var(--amber-400);
  outline: 2px solid var(--amber-400);
  outline-offset: 2px;
}

.page-about .stage__hint {
  font-size: 11.5px;
  letter-spacing: 0.08em;
  color: var(--stone-400);
}

/* ---------- 双端时段对照 ---------- */
.page-about .duo {
  display: grid;
  grid-template-columns: minmax(0, 1fr);
  gap: 14px;
  margin: 4px 0 18px;
}

.page-about .duo__col {
  padding: 14px 16px;
  border: 1px solid rgba(11, 20, 24, 0.16);
  border-left: 3px solid var(--clay-500);
  background: rgba(11, 20, 24, 0.035);
}

.page-about .duo__label {
  margin: 0 0 6px;
  font-size: 11.5px;
  letter-spacing: 0.14em;
  color: var(--ink-900);
}

.page-about .duo__text {
  margin: 0;
  font-size: 15px;
  line-height: 1.7;
  color: rgba(11, 20, 24, 0.78);
}

/* ---------- 团队分工折叠卡 ---------- */
.page-about .duties {
  display: flex;
  flex-direction: column;
  gap: 10px;
  margin: 4px 0 20px;
}

.page-about .duty {
  border: 1px solid var(--hair);
  background: rgba(243, 241, 234, 0.03);
}

.page-about .duty[open] {
  border-color: var(--neon-line);
  background: rgba(53, 224, 214, 0.05);
}

.page-about .duty__summary {
  display: flex;
  align-items: center;
  gap: 12px;
  padding: 13px 16px;
  cursor: pointer;
  list-style: none;
}

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

.page-about .duty__summary::after {
  content: "+";
  margin-left: auto;
  font-family: var(--font-mono);
  font-size: 15px;
  color: var(--neon-400);
  transition: transform 200ms var(--ease);
}

.page-about .duty[open] .duty__summary::after {
  content: "−";
}

.page-about .duty__summary:focus-visible {
  outline: 2px solid var(--neon-400);
  outline-offset: -2px;
}

.page-about .duty__name {
  font-size: 15.5px;
  color: var(--paper-50);
}

.page-about .duty__size {
  font-size: 12px;
  letter-spacing: 0.08em;
  color: var(--amber-400);
}

.page-about .duty__body {
  padding: 0 16px 14px;
}

.page-about .duty__list {
  margin: 0;
  padding: 0;
  list-style: none;
}

.page-about .duty__list li {
  position: relative;
  padding: 5px 0 5px 16px;
  font-size: 14.5px;
  line-height: 1.7;
  color: var(--stone-400);
}

.page-about .duty__list li::before {
  content: "";
  position: absolute;
  left: 0;
  top: 14px;
  width: 6px;
  height: 1px;
  background: var(--neon-600);
}

/* ---------- 三档节奏时间线 ---------- */
.page-about .cadence {
  list-style: none;
  margin: 4px 0 0;
  padding: 0 0 0 20px;
  border-left: 1px solid rgba(11, 20, 24, 0.18);
}

.page-about .cadence__item {
  position: relative;
  padding: 0 0 22px;
}

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

.page-about .cadence__dot {
  position: absolute;
  left: -25px;
  top: 6px;
  width: 9px;
  height: 9px;
  border-radius: 50%;
  background: var(--paper-50);
  box-shadow: inset 0 0 0 2px var(--clay-500);
}

.page-about .cadence__item:first-child .cadence__dot {
  box-shadow: inset 0 0 0 2px var(--amber-400);
}

.page-about .cadence__when {
  margin: 0 0 4px;
  font-size: 12px;
  letter-spacing: 0.14em;
  color: var(--clay-500);
}

.page-about .cadence__what {
  margin: 0 0 6px;
  font-family: var(--font-display);
  font-weight: 700;
  font-size: 18px;
  line-height: 1.4;
  color: var(--ink-900);
}

.page-about .cadence__how {
  margin: 0;
  max-width: 58ch;
  font-size: 15px;
  line-height: 1.75;
  color: rgba(11, 20, 24, 0.76);
}

/* ---------- 结构调整卡片 ---------- */
.page-about .adj-grid {
  display: grid;
  grid-template-columns: minmax(0, 1fr);
  gap: 14px;
  margin: 4px 0 22px;
}

.page-about .adj {
  position: relative;
  padding: 16px 16px 15px;
  border: 1px solid var(--hair);
  background: rgba(14, 44, 69, 0.55);
  transition: border-color 160ms var(--ease);
}

.page-about .adj::before {
  content: "";
  position: absolute;
  left: -1px;
  top: 14px;
  width: 2px;
  height: 18px;
  background: var(--neon-600);
  transition: background 160ms var(--ease);
}

.page-about .adj:hover {
  border-color: var(--neon-line);
}

.page-about .adj:hover::before {
  background: var(--neon-400);
}

.page-about .adj__title {
  margin: 0 0 8px;
  font-family: var(--font-display);
  font-weight: 700;
  font-size: 17px;
  line-height: 1.35;
  color: var(--paper-50);
}

.page-about .adj__desc {
  margin: 0 0 10px;
  font-size: 14.5px;
  line-height: 1.7;
  color: rgba(243, 241, 234, 0.7);
}

.page-about .adj__merge {
  margin: 0;
  font-size: 11.5px;
  letter-spacing: 0.06em;
  color: var(--neon-400);
  opacity: 0.42;
  transition: opacity 200ms var(--ease);
}

.page-about .adj:hover .adj__merge {
  opacity: 1;
}

/* ---------- 收束链接 ---------- */
.page-about .about-links {
  display: grid;
  grid-template-columns: minmax(0, 1fr);
  gap: 12px;
  margin: 6px 0 20px;
}

.page-about .about-link {
  position: relative;
  display: flex;
  flex-direction: column;
  gap: 5px;
  padding: 16px 40px 16px 16px;
  border: 1px solid rgba(11, 20, 24, 0.18);
  background: rgba(255, 255, 255, 0.5);
  text-decoration: none;
  transition: border-color 160ms var(--ease), background 160ms var(--ease);
}

.page-about .about-link:hover,
.page-about .about-link:focus-visible {
  border-color: var(--clay-500);
  background: rgba(180, 105, 79, 0.07);
  outline: none;
}

.page-about .about-link__go {
  position: absolute;
  right: 15px;
  top: 16px;
  font-size: 15px;
  color: var(--clay-500);
  transition: transform 160ms var(--ease);
}

.page-about .about-link:hover .about-link__go {
  transform: translateX(3px);
}

.page-about .about-link__name {
  font-family: var(--font-display);
  font-weight: 700;
  font-size: 17px;
  letter-spacing: -0.01em;
  color: var(--ink-900);
}

.page-about .about-link__desc {
  font-size: 14px;
  line-height: 1.65;
  color: rgba(11, 20, 24, 0.72);
}

/* ============================================================
   平板及以上
   ============================================================ */
@media (min-width: 700px) {
  .page-about .about-hero__stats {
    grid-template-columns: repeat(4, minmax(0, 1fr));
  }

  .page-about .stage {
    padding: 28px 28px 30px;
    box-shadow: 7px 7px 0 -1px var(--abyss-950), 7px 7px 0 0 var(--hair);
  }

  .page-about .stage--paper {
    box-shadow: 7px 7px 0 -1px var(--abyss-950), 7px 7px 0 0 rgba(140, 154, 166, 0.34);
  }

  .page-about .duo {
    grid-template-columns: repeat(2, minmax(0, 1fr));
    gap: 16px;
  }

  .page-about .about-links {
    grid-template-columns: repeat(3, minmax(0, 1fr));
  }

  .page-about .about-link {
    padding: 18px 38px 18px 16px;
  }

  .page-about .adj-grid {
    grid-template-columns: repeat(2, minmax(0, 1fr));
    gap: 18px 20px;
    padding-bottom: 18px;
  }

  .page-about .adj:nth-child(2n) {
    transform: translateY(20px);
  }

  .page-about .tier__item {
    flex-direction: row;
    align-items: baseline;
    gap: 16px;
  }

  .page-about .tier__key {
    flex: none;
    width: 108px;
  }
}

/* ============================================================
   桌面：左侧轴常驻 + 右侧内容
   ============================================================ */
@media (min-width: 980px) {
  .page-about .about-hero {
    padding-bottom: 56px;
  }

  .page-about .about-hero__inner {
    padding-top: 22px;
  }

  .page-about .about-shell {
    grid-template-columns: var(--about-axis-w) minmax(0, 1fr);
    gap: var(--about-shell-gap);
    padding-top: 56px;
    padding-bottom: 84px;
    align-items: start;
  }

  .page-about .about-axis {
    position: sticky;
    top: 32px;
    z-index: 2;
    padding: 0 0 0 2px;
    background: none;
    border-bottom: 0;
  }

  .page-about .about-axis__list {
    flex-direction: column;
    gap: 0;
    overflow: visible;
    padding: 0;
  }

  .page-about .about-axis__node {
    position: relative;
    display: flex;
    align-items: baseline;
    gap: 9px;
    padding: 11px 0 11px 15px;
    border: 0;
    border-left: 1px solid var(--hair);
    white-space: normal;
  }

  .page-about .about-axis__node::before {
    content: "";
    position: absolute;
    left: -4px;
    top: 16px;
    width: 7px;
    height: 7px;
    border-radius: 50%;
    background: var(--abyss-950);
    box-shadow: inset 0 0 0 1px var(--hair);
    transition: background 160ms var(--ease), box-shadow 160ms var(--ease);
  }

  .page-about .about-axis__node:hover::before,
  .page-about .about-axis__node:focus-visible::before {
    background: var(--neon-400);
    box-shadow: 0 0 9px var(--neon-line);
  }

  .page-about .about-stream {
    gap: 44px;
  }

  .page-about .stage {
    padding: 32px 36px 36px;
    scroll-margin-top: 40px;
  }

  .page-about .stage:nth-child(even) {
    margin-right: 34px;
  }

  .page-about .stage:nth-child(odd) {
    margin-left: 34px;
  }

  .page-about .adj:nth-child(2n) {
    transform: translateY(26px);
  }
}

/* ---------- 触屏：折叠卡与悬停信息始终可读 ---------- */
@media (hover: none) {
  .page-about .adj__merge {
    opacity: 1;
  }
}

@media (prefers-reduced-motion: reduce) {
  .page-about .about-axis__node,
  .page-about .about-link,
  .page-about .about-link__go,
  .page-about .adj,
  .page-about .adj__merge,
  .page-about .code-chip {
    transition: none;
  }

  .page-about .about-link:hover .about-link__go {
    transform: none;
  }

  .page-about .adj:nth-child(2n) {
    transform: none;
  }
}