.page-about {
  --about-hair: 1px solid var(--line);
  --about-pad: clamp(18px, 3.4vw, 34px);
  --about-gap: clamp(28px, 4vw, 48px);
}

/* ---------- HERO ---------- */
.page-about .about-hero {
  position: relative;
  overflow: hidden;
  padding: clamp(38px, 6vw, 76px) 0 clamp(54px, 7vw, 100px);
}

.page-about .about-hero::before {
  content: "";
  position: absolute;
  top: -32%;
  right: -12%;
  width: min(620px, 78vw);
  height: min(620px, 78vw);
  background: radial-gradient(circle at 34% 34%, rgba(34, 224, 210, 0.16), rgba(124, 92, 255, 0.12) 46%, transparent 72%);
  pointer-events: none;
}

.page-about .about-hero::after {
  content: "";
  position: absolute;
  right: -12vw;
  bottom: -22%;
  width: min(460px, 62vw);
  height: min(460px, 62vw);
  background: linear-gradient(142deg, rgba(255, 122, 41, 0.22), rgba(255, 122, 41, 0) 68%);
  clip-path: polygon(42% 0, 100% 0, 100% 100%, 0 100%);
  pointer-events: none;
}

.page-about .about-hero > .shell {
  position: relative;
  z-index: 1;
}

.page-about .about-hero__grid {
  display: grid;
  grid-template-columns: minmax(0, 1fr);
  gap: clamp(30px, 4.4vw, 52px);
  margin-top: clamp(26px, 4vw, 46px);
}

.page-about .about-hero__title {
  margin: 16px 0 0;
  font-family: var(--font-display);
  font-weight: 200;
  font-size: clamp(33px, 6.6vw, 74px);
  line-height: 1.14;
  letter-spacing: 0.045em;
  max-width: 15em;
}

.page-about .about-hero__intro {
  margin: 22px 0 0;
  max-width: 44ch;
  font-size: 16px;
  line-height: 1.85;
  color: var(--text-muted);
}

.page-about .about-facts {
  display: grid;
  grid-template-columns: repeat(3, minmax(0, 1fr));
  gap: 1px;
  background: var(--line);
  border: var(--about-hair);
  align-self: end;
}

.page-about .about-fact {
  background: rgba(12, 20, 36, 0.82);
  padding: 16px 14px 18px;
}

.page-about .about-fact__num {
  margin: 0;
  font-family: var(--font-mono);
  font-weight: 400;
  font-size: clamp(19px, 5vw, 32px);
  line-height: 1.1;
  letter-spacing: 0.01em;
  color: var(--cyan);
  font-variant-numeric: tabular-nums;
}

.page-about .about-fact:nth-child(2) .about-fact__num {
  color: var(--orange);
}

.page-about .about-fact:nth-child(3) .about-fact__num {
  color: var(--violet);
}

.page-about .about-fact__label {
  margin: 9px 0 0;
  font-size: 11.5px;
  letter-spacing: 0.14em;
  color: var(--text-muted);
  line-height: 1.5;
}

/* ---------- FRAME ---------- */
.page-about .about-frame {
  display: grid;
  grid-template-columns: minmax(0, 1fr);
  gap: clamp(34px, 5vw, 60px);
  padding-bottom: clamp(64px, 8vw, 132px);
}

.page-about .about-flow {
  display: grid;
  gap: clamp(62px, 8vw, 116px);
  min-width: 0;
}

/* ---------- INDEX ---------- */
.page-about .about-index {
  display: none;
}

.page-about .about-index__label {
  margin: 0 0 16px;
  padding-bottom: 12px;
  border-bottom: var(--about-hair);
  font-family: var(--font-mono);
  font-size: 11px;
  letter-spacing: 0.26em;
  text-transform: uppercase;
  color: var(--text-muted);
}

.page-about .about-index ol {
  list-style: none;
  margin: 0;
  padding: 0;
  display: grid;
  gap: 1px;
}

.page-about .about-index a {
  display: flex;
  align-items: baseline;
  gap: 10px;
  padding: 9px 0;
  border-bottom: 1px solid transparent;
  font-size: 13.5px;
  letter-spacing: 0.04em;
  color: var(--text-muted);
  text-decoration: none;
  transition: color 0.25s var(--ease), border-color 0.25s var(--ease);
}

.page-about .about-index a:hover,
.page-about .about-index a:focus-visible {
  color: var(--text);
  border-bottom-color: var(--cyan);
}

.page-about .about-index__num {
  font-family: var(--font-mono);
  font-size: 11px;
  letter-spacing: 0.1em;
  color: var(--cyan);
}

/* ---------- CHAPTER ---------- */
.page-about .about-chapter {
  min-width: 0;
  scroll-margin-top: calc(var(--header-h) + 34px);
}

.page-about .about-chapter__head {
  border-top: var(--about-hair);
  padding-top: clamp(20px, 2.6vw, 30px);
}

.page-about .about-chapter__title {
  margin: 12px 0 0;
  font-family: var(--font-display);
  font-weight: 200;
  font-size: clamp(25px, 3.6vw, 40px);
  line-height: 1.26;
  letter-spacing: 0.05em;
  max-width: 22em;
}

.page-about .about-text {
  margin: 20px 0 0;
  max-width: 62ch;
  font-size: 16px;
  line-height: 1.85;
  color: var(--text-muted);
}

.page-about .about-text + .about-text {
  margin-top: 14px;
}

/* ---------- TROUBLE ---------- */
.page-about .trouble-list {
  list-style: none;
  margin: var(--about-gap) 0 0;
  padding: 0;
}

.page-about .trouble {
  display: grid;
  grid-template-columns: auto minmax(0, 1fr);
  gap: 4px 18px;
  padding: 22px 0;
  border-top: var(--about-hair);
}

.page-about .trouble:last-child {
  border-bottom: var(--about-hair);
}

.page-about .trouble__idx {
  margin: 0;
  padding-top: 4px;
  font-family: var(--font-mono);
  font-size: 12px;
  letter-spacing: 0.2em;
  color: var(--orange);
}

.page-about .trouble__title {
  margin: 0;
  font-size: 17.5px;
  font-weight: 500;
  letter-spacing: 0.03em;
  color: var(--text);
}

.page-about .trouble__body {
  grid-column: 2;
  margin: 8px 0 0;
  max-width: 60ch;
  font-size: 15.5px;
  line-height: 1.8;
  color: var(--text-muted);
}

/* ---------- ZONE STRIP ---------- */
.page-about .zone-strip {
  list-style: none;
  margin: var(--about-gap) 0 0;
  padding: 0;
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(148px, 1fr));
  gap: 1px;
  background: var(--line);
  border: var(--about-hair);
}

.page-about .zone {
  position: relative;
  background: var(--ink-800);
  padding: 18px 16px 20px;
  border-top: 2px solid transparent;
  transition: background 0.3s var(--ease), border-color 0.3s var(--ease);
}

.page-about .zone:hover,
.page-about .zone:focus-within {
  background: #101B2F;
  border-top-color: var(--cyan);
}

.page-about .zone__tag {
  display: block;
  font-family: var(--font-mono);
  font-size: 13px;
  letter-spacing: 0.16em;
  color: var(--text);
}

.page-about .zone__duty {
  margin: 10px 0 0;
  font-size: 13px;
  line-height: 1.7;
  color: var(--text-muted);
  transition: color 0.3s var(--ease);
}

.page-about .zone:hover .zone__duty,
.page-about .zone:focus-within .zone__duty {
  color: var(--text);
}

/* ---------- FIGURE ---------- */
.page-about .about-figure {
  position: relative;
  margin: var(--about-gap) 0 0;
  border: var(--about-hair);
  overflow: hidden;
  background: var(--ink-800);
}

.page-about .about-figure::before {
  content: "";
  position: absolute;
  top: 0;
  left: 0;
  width: 72px;
  height: 2px;
  background: var(--cyan);
  z-index: 1;
}

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

.page-about .about-figure figcaption {
  padding: 12px 16px;
  border-top: var(--about-hair);
  background: rgba(12, 20, 36, 0.72);
  font-size: 12.5px;
  line-height: 1.6;
  letter-spacing: 0.06em;
  color: var(--text-muted);
}

/* ---------- TIER ---------- */
.page-about .tier-list {
  margin: var(--about-gap) 0 0;
  border-top: var(--about-hair);
}

.page-about .tier {
  border-bottom: var(--about-hair);
}

.page-about .tier > summary {
  display: flex;
  flex-wrap: wrap;
  align-items: baseline;
  gap: 10px 16px;
  padding: 18px 0;
  cursor: pointer;
  list-style: none;
}

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

.page-about .tier > summary::after {
  content: "";
  margin-left: auto;
  align-self: center;
  width: 9px;
  height: 9px;
  border-right: 1.5px solid var(--text-muted);
  border-bottom: 1.5px solid var(--text-muted);
  transform: rotate(45deg);
  transition: transform 0.3s var(--ease), border-color 0.3s var(--ease);
}

.page-about .tier[open] > summary::after {
  transform: rotate(-135deg);
  border-color: var(--cyan);
}

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

.page-about .tier__num {
  font-family: var(--font-mono);
  font-size: 12px;
  letter-spacing: 0.2em;
  color: var(--cyan);
}

.page-about .tier__name {
  font-size: 17px;
  letter-spacing: 0.05em;
  color: var(--text);
  transition: color 0.25s var(--ease);
}

.page-about .tier__meta {
  font-size: 12.5px;
  letter-spacing: 0.1em;
  color: var(--text-muted);
}

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

.page-about .tier__body p {
  margin: 0;
  max-width: 62ch;
  font-size: 15.5px;
  line-height: 1.8;
  color: var(--text-muted);
}

/* ---------- RANK RULES ---------- */
.page-about .rank-rules {
  list-style: none;
  margin: var(--about-gap) 0 0;
  padding: 0;
}

.page-about .rank-rule {
  display: grid;
  grid-template-columns: 3px minmax(0, 1fr);
  gap: 18px;
  padding: 20px 0;
  border-top: var(--about-hair);
}

.page-about .rank-rule:last-child {
  border-bottom: var(--about-hair);
}

.page-about .rank-rule__mark {
  display: block;
  background: var(--cyan);
}

.page-about .rank-rule:nth-child(2) .rank-rule__mark {
  background: var(--orange);
}

.page-about .rank-rule:nth-child(3) .rank-rule__mark {
  background: var(--violet);
}

.page-about .rank-rule__title {
  display: flex;
  align-items: center;
  gap: 8px;
  margin: 0;
  font-size: 17px;
  font-weight: 500;
  letter-spacing: 0.03em;
  color: var(--text);
}

.page-about .rank-rule__body {
  margin: 9px 0 0;
  max-width: 60ch;
  font-size: 15.5px;
  line-height: 1.8;
  color: var(--text-muted);
}

.page-about .delta-mark {
  flex: none;
  width: 13px;
  height: 13px;
  color: var(--cyan);
}

.page-about .delta-mark--down {
  color: var(--alert);
}

.page-about .about-note {
  margin: var(--about-gap) 0 0;
  padding: 18px 20px;
  max-width: 62ch;
  border-left: 2px solid var(--orange);
  background: rgba(255, 122, 41, 0.06);
  font-size: 15px;
  line-height: 1.8;
  color: var(--text);
}

/* ---------- PHASES ---------- */
.page-about .phase-track {
  list-style: none;
  margin: var(--about-gap) 0 0;
  padding: 0 0 0 22px;
  position: relative;
}

.page-about .phase-track::before {
  content: "";
  position: absolute;
  left: 4px;
  top: 8px;
  bottom: 8px;
  width: 1px;
  background: var(--line);
}

.page-about .phase {
  position: relative;
  padding-bottom: clamp(26px, 3.6vw, 40px);
}

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

.page-about .phase::before {
  content: "";
  position: absolute;
  left: -22px;
  top: 9px;
  width: 9px;
  height: 9px;
  background: var(--ink-900);
  border: 1px solid var(--cyan);
  transform: rotate(45deg);
}

.page-about .phase:last-child::before {
  background: var(--cyan);
}

.page-about .phase__idx {
  margin: 0;
  font-family: var(--font-mono);
  font-size: 11px;
  letter-spacing: 0.24em;
  color: var(--cyan);
}

.page-about .phase__name {
  margin: 8px 0 0;
  font-size: 17px;
  font-weight: 500;
  letter-spacing: 0.03em;
  color: var(--text);
}

.page-about .phase__body {
  margin: 8px 0 0;
  max-width: 58ch;
  font-size: 15px;
  line-height: 1.8;
  color: var(--text-muted);
}

/* ---------- PLEDGE ---------- */
.page-about .pledge-list {
  list-style: none;
  margin: var(--about-gap) 0 0;
  padding: 0;
  border-top: var(--about-hair);
}

.page-about .pledge {
  display: grid;
  gap: 6px;
  padding: 20px 0;
  border-bottom: var(--about-hair);
}

.page-about .pledge__key {
  margin: 0;
  font-family: var(--font-mono);
  font-size: 11.5px;
  letter-spacing: 0.24em;
  color: var(--orange);
}

.page-about .pledge__val {
  margin: 0;
  max-width: 58ch;
  font-size: 15.5px;
  line-height: 1.8;
  color: var(--text-muted);
}

/* ---------- NEXT ---------- */
.page-about .about-next {
  margin-top: clamp(20px, 3vw, 36px);
  padding: clamp(26px, 4vw, 44px) clamp(20px, 3vw, 36px);
  border: var(--about-hair);
  background: linear-gradient(152deg, rgba(34, 224, 210, 0.08), rgba(124, 92, 255, 0.07) 52%, rgba(255, 122, 41, 0.05));
}

.page-about .about-next__title {
  margin: 0;
  font-family: var(--font-display);
  font-weight: 200;
  font-size: clamp(21px, 2.9vw, 30px);
  line-height: 1.3;
  letter-spacing: 0.05em;
}

.page-about .about-next__list {
  list-style: none;
  margin: 24px 0 0;
  padding: 0;
  display: grid;
  gap: 1px;
  background: var(--line);
  border: var(--about-hair);
}

.page-about .about-next__list li {
  background: rgba(5, 7, 14, 0.62);
}

.page-about .about-next__list a {
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 16px;
  padding: 16px 18px;
  font-size: 15px;
  letter-spacing: 0.03em;
  color: var(--text);
  text-decoration: none;
  transition: background 0.25s var(--ease), color 0.25s var(--ease);
}

.page-about .about-next__list a::after {
  content: "\2192";
  font-family: var(--font-mono);
  color: var(--cyan);
  flex: none;
}

.page-about .about-next__list a:hover,
.page-about .about-next__list a:focus-visible {
  background: rgba(34, 224, 210, 0.08);
  color: var(--cyan);
}

/* ---------- MEDIA QUERIES ---------- */
@media (min-width: 560px) {
  .page-about .about-next__list {
    grid-template-columns: repeat(2, minmax(0, 1fr));
  }
}

@media (min-width: 720px) {
  .page-about .pledge {
    grid-template-columns: 150px minmax(0, 1fr);
    align-items: baseline;
    gap: 24px;
  }
}

@media (min-width: 900px) {
  .page-about .about-hero__grid {
    grid-template-columns: minmax(0, 1.55fr) minmax(0, 1fr);
    align-items: end;
  }

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

  .page-about .about-fact {
    padding: 18px 20px 20px;
  }

  .page-about .about-fact__num {
    font-size: clamp(24px, 2.6vw, 34px);
  }
}

@media (min-width: 1000px) {
  .page-about .about-frame {
    grid-template-columns: 208px minmax(0, 1fr);
    gap: clamp(48px, 5vw, 88px);
  }

  .page-about .about-index {
    display: block;
    align-self: start;
    position: sticky;
    top: calc(var(--header-h) + 28px);
  }
}

@media (prefers-reduced-motion: reduce) {
  .page-about .zone,
  .page-about .zone__duty,
  .page-about .tier > summary::after,
  .page-about .tier__name,
  .page-about .about-next__list a,
  .page-about .about-index a {
    transition: none;
  }
}
<<<END>>>