.page-about {
  --about-cut: 14px;
  --about-sticky-top: calc(var(--strip-h, 52px) + 24px);
  position: relative;
}

/* ---------- Hero ---------- */
.page-about .about-hero {
  position: relative;
  padding: 40px 0 72px;
  overflow: hidden;
}

.page-about .about-hero::before {
  content: "";
  position: absolute;
  top: -32%;
  right: -22%;
  width: 78vw;
  height: 78vw;
  max-width: 900px;
  max-height: 900px;
  background: radial-gradient(circle, rgba(76, 224, 179, 0.14), rgba(76, 224, 179, 0) 62%);
  pointer-events: none;
  z-index: 0;
}

.page-about .about-hero__inner {
  position: relative;
  z-index: 1;
  display: grid;
  grid-template-columns: 1fr;
  gap: 28px;
}

.page-about .about-hero__rail {
  display: none;
}

.page-about .about-hero__body h1 {
  margin: 10px 0 0;
  font-family: var(--font-display);
  font-weight: 700;
  font-size: clamp(32px, 5.6vw, 62px);
  line-height: 1.14;
  letter-spacing: -0.01em;
  color: var(--text);
}

.page-about .about-hero__lede {
  margin: 22px 0 0;
  max-width: 62ch;
  font-size: 16.5px;
  line-height: 1.85;
  color: var(--muted);
}

.page-about .about-hero__stats {
  margin: 40px 0 0;
  padding: 0;
  list-style: none;
  display: grid;
  grid-template-columns: repeat(2, minmax(0, 1fr));
  gap: 1px;
  background: var(--line);
  border: 1px solid var(--line);
}

.page-about .about-hero__stats li {
  background: var(--panel);
  padding: 18px 16px 20px;
  display: flex;
  flex-direction: column;
  gap: 6px;
  min-width: 0;
}

.page-about .about-hero__num {
  font-family: var(--font-mono);
  font-size: clamp(24px, 3vw, 32px);
  font-weight: 600;
  font-variant-numeric: tabular-nums;
  color: var(--text);
  line-height: 1.1;
}

.page-about .about-hero__stats li:nth-child(1) .about-hero__num { color: var(--cyan); }
.page-about .about-hero__stats li:nth-child(2) .about-hero__num { color: var(--amber); }
.page-about .about-hero__stats li:nth-child(3) .about-hero__num { color: var(--orange); }

.page-about .about-hero__tag {
  font-size: 12px;
  letter-spacing: 0.1em;
  color: var(--muted);
}

/* ---------- Section shell ---------- */
.page-about .about-section {
  position: relative;
  padding: clamp(56px, 8vw, 112px) 0;
}

.page-about .about-section + .about-section {
  border-top: 1px solid var(--line);
}

.page-about .about-section::after {
  content: "";
  position: absolute;
  left: 0;
  right: 0;
  top: -1px;
  height: 14px;
  background: linear-gradient(100deg, rgba(76, 224, 179, 0.12), rgba(255, 122, 41, 0) 70%);
  transform: skewY(-8deg);
  transform-origin: left top;
  pointer-events: none;
}

.page-about .about-split {
  display: grid;
  grid-template-columns: 1fr;
  gap: 24px;
}

.page-about .about-rail {
  display: flex;
  flex-direction: row;
  align-items: center;
  gap: 14px;
}

.page-about .about-rail__num {
  font-family: var(--font-display);
  font-size: clamp(40px, 7vw, 76px);
  font-weight: 700;
  line-height: 0.9;
  letter-spacing: -0.03em;
  color: transparent;
  -webkit-text-stroke: 1px rgba(76, 224, 179, 0.55);
}

.page-about .about-rail__label {
  font-size: 12px;
  letter-spacing: 0.28em;
  color: var(--muted);
  white-space: nowrap;
}

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

.page-about .about-body h2 {
  margin: 8px 0 22px;
  font-family: var(--font-display);
  font-weight: 700;
  font-size: clamp(25px, 3.4vw, 40px);
  line-height: 1.22;
  letter-spacing: -0.01em;
  color: var(--text);
}

.page-about .about-body > p {
  max-width: 64ch;
  font-size: 16px;
  line-height: 1.85;
  color: var(--muted);
}

.page-about .about-body > p + p {
  margin-top: 16px;
}

.page-about .about-body a {
  color: var(--cyan);
  text-decoration: none;
  border-bottom: 1px solid rgba(76, 224, 179, 0.4);
  transition: border-color 0.16s var(--ease), color 0.16s var(--ease);
}

.page-about .about-body a:hover,
.page-about .about-body a:focus-visible {
  color: var(--amber);
  border-bottom-color: var(--amber);
}

/* ---------- Scenarios ---------- */
.page-about .about-scenarios {
  margin-top: 36px;
  display: grid;
  grid-template-columns: 1fr;
  gap: 1px;
  background: var(--line);
  border: 1px solid var(--line);
  clip-path: polygon(0 0, calc(100% - var(--about-cut)) 0, 100% var(--about-cut), 100% 100%, var(--about-cut) 100%, 0 calc(100% - var(--about-cut)));
}

.page-about .about-scenario {
  background: var(--panel);
  padding: 22px 20px 26px;
  display: flex;
  flex-direction: column;
  gap: 12px;
  min-width: 0;
}

.page-about .about-scenario h3 {
  margin: 0;
  font-size: 17px;
  font-weight: 700;
  line-height: 1.45;
  color: var(--text);
}

.page-about .about-scenario p {
  margin: 0;
  font-size: 14.5px;
  line-height: 1.8;
  color: var(--muted);
}

/* ---------- Figures ---------- */
.page-about .about-figure {
  margin: 0 0 28px;
}

.page-about .about-figure--end {
  margin: 40px 0 0;
}

.page-about .about-figure--wide {
  margin: 44px 0 0;
}

.page-about .about-figure img {
  display: block;
  width: 100%;
  height: auto;
  object-fit: cover;
  border: 1px solid var(--line);
  background: var(--panel);
}

.page-about .about-figure figcaption {
  margin-top: 10px;
  font-size: 12px;
  letter-spacing: 0.06em;
  line-height: 1.7;
  color: var(--muted);
}

/* ---------- Quote ---------- */
.page-about .about-quote {
  margin: 36px 0 0;
  padding: 24px 24px 26px 28px;
  background: var(--cream);
  color: var(--cream-ink);
  border-left: 4px solid var(--orange);
  clip-path: polygon(0 0, calc(100% - var(--about-cut)) 0, 100% var(--about-cut), 100% 100%, var(--about-cut) 100%, 0 calc(100% - var(--about-cut)));
}

.page-about .about-quote p {
  margin: 0;
  font-size: 17px;
  line-height: 1.8;
  font-weight: 600;
  color: var(--cream-ink);
}

.page-about .about-quote cite {
  display: block;
  margin-top: 12px;
  font-style: normal;
  font-size: 12px;
  letter-spacing: 0.12em;
  color: #6F5C46;
}

/* ---------- Steps ---------- */
.page-about .about-steps {
  margin: 36px 0 0;
  padding: 0;
  list-style: none;
}

.page-about .about-step {
  position: relative;
  padding: 0 0 30px 32px;
}

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

.page-about .about-step::before {
  content: "";
  position: absolute;
  left: 7px;
  top: 20px;
  bottom: 0;
  width: 1px;
  background: linear-gradient(to bottom, var(--line), rgba(36, 65, 58, 0) 92%);
}

.page-about .about-step:last-child::before {
  display: none;
}

.page-about .about-step__dot {
  position: absolute;
  left: 0;
  top: 5px;
  width: 15px;
  height: 15px;
  border-radius: 50%;
  border: 1px solid var(--cyan);
  background: var(--bg);
  transition: background 0.16s var(--ease);
}

.page-about .about-step__dot::after {
  content: "";
  position: absolute;
  inset: 4px;
  border-radius: 50%;
  background: var(--cyan);
}

.page-about .about-step__head {
  display: flex;
  flex-wrap: wrap;
  align-items: baseline;
  gap: 8px 14px;
  margin-bottom: 8px;
}

.page-about .about-step__no {
  font-family: var(--font-mono);
  font-size: 13px;
  font-weight: 600;
  letter-spacing: 0.14em;
  color: var(--amber);
}

.page-about .about-step__title {
  margin: 0;
  font-size: 18px;
  font-weight: 700;
  line-height: 1.4;
  color: var(--text);
}

.page-about .about-step__meta {
  font-size: 12px;
  letter-spacing: 0.06em;
  color: var(--muted);
}

.page-about .about-step__text {
  margin: 0;
  max-width: 62ch;
  font-size: 15px;
  line-height: 1.8;
  color: var(--muted);
}

.page-about .about-step:hover .about-step__dot {
  background: rgba(76, 224, 179, 0.18);
}

/* ---------- Rhythm ---------- */
.page-about .about-rhythm {
  margin-top: 36px;
  display: grid;
  grid-template-columns: 1fr;
  gap: 14px;
}

.page-about .about-rhythm__item {
  background: var(--panel);
  border: 1px solid var(--line);
  padding: 20px 20px 22px;
  display: flex;
  flex-direction: column;
  gap: 8px;
  min-width: 0;
  clip-path: polygon(0 0, calc(100% - var(--about-cut)) 0, 100% var(--about-cut), 100% 100%, var(--about-cut) 100%, 0 calc(100% - var(--about-cut)));
  transition: transform 0.16s var(--ease), border-color 0.16s var(--ease);
}

.page-about .about-rhythm__item:hover {
  transform: translateY(-2px);
  border-color: var(--cyan);
}

.page-about .about-rhythm__label {
  font-size: 12px;
  letter-spacing: 0.12em;
  color: var(--muted);
}

.page-about .about-rhythm__value {
  font-family: var(--font-mono);
  font-size: clamp(22px, 2.6vw, 28px);
  font-weight: 600;
  font-variant-numeric: tabular-nums;
  line-height: 1.15;
  color: var(--cyan);
}

.page-about .about-rhythm__item:nth-child(2) .about-rhythm__value { color: var(--orange); }
.page-about .about-rhythm__item:nth-child(3) .about-rhythm__value { color: var(--amber); }
.page-about .about-rhythm__item:nth-child(4) .about-rhythm__value { color: var(--text); }

.page-about .about-rhythm__note {
  margin: 0;
  font-size: 14px;
  line-height: 1.75;
  color: var(--muted);
}

/* ---------- Stages ---------- */
.page-about .about-stages {
  margin-top: 36px;
  display: grid;
  grid-template-columns: 1fr;
  gap: 16px;
}

.page-about .about-stage {
  position: relative;
  padding: 22px 20px 24px;
  background: var(--panel);
  border: 1px solid var(--line);
  min-width: 0;
  clip-path: polygon(0 0, calc(100% - var(--about-cut)) 0, 100% var(--about-cut), 100% 100%, var(--about-cut) 100%, 0 calc(100% - var(--about-cut)));
  transition: transform 0.16s var(--ease), border-color 0.16s var(--ease);
}

.page-about .about-stage:hover {
  transform: translateY(-2px);
  border-color: var(--cyan);
}

.page-about .about-stage__year {
  display: inline-block;
  font-family: var(--font-mono);
  font-size: 13px;
  font-weight: 600;
  letter-spacing: 0.16em;
  color: var(--orange);
  border: 1px solid rgba(255, 122, 41, 0.4);
  padding: 3px 8px;
  margin-bottom: 14px;
}

.page-about .about-stage h3 {
  margin: 0 0 10px;
  font-size: 17px;
  font-weight: 700;
  line-height: 1.45;
  color: var(--text);
}

.page-about .about-stage p {
  margin: 0;
  font-size: 14.5px;
  line-height: 1.8;
  color: var(--muted);
}

/* ---------- Corrections ---------- */
.page-about .about-error {
  margin-top: 32px;
  display: grid;
  grid-template-columns: 1fr;
  gap: 14px;
}

.page-about .about-error__card {
  background: var(--panel-soft);
  border: 1px solid var(--line);
  padding: 20px 20px 22px;
  display: flex;
  flex-direction: column;
  gap: 8px;
  min-width: 0;
  clip-path: polygon(0 0, calc(100% - var(--about-cut)) 0, 100% var(--about-cut), 100% 100%, var(--about-cut) 100%, 0 calc(100% - var(--about-cut)));
}

.page-about .about-error__label {
  font-size: 12px;
  letter-spacing: 0.12em;
  color: var(--muted);
}

.page-about .about-error__value {
  font-family: var(--font-mono);
  font-size: clamp(22px, 2.6vw, 28px);
  font-weight: 600;
  font-variant-numeric: tabular-nums;
  line-height: 1.15;
  color: var(--cyan);
}

.page-about .about-error__card:nth-child(2) .about-error__value {
  color: var(--amber);
}

.page-about .about-error__card p {
  margin: 0;
  font-size: 14px;
  line-height: 1.75;
  color: var(--muted);
}

.page-about .about-actions {
  margin-top: 28px;
  display: flex;
  flex-wrap: wrap;
  gap: 12px;
}

.page-about .about-mail {
  margin-top: 20px;
  font-size: 14px;
  line-height: 1.9;
  color: var(--muted);
}

.page-about .about-mail .mono {
  font-family: var(--font-mono);
  font-size: 13.5px;
  color: var(--text);
  word-break: break-all;
}

/* ---------- Responsive ---------- */
@media (min-width: 640px) {
  .page-about .about-scenarios {
    grid-template-columns: repeat(3, minmax(0, 1fr));
  }

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

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

@media (min-width: 880px) {
  .page-about .about-hero {
    padding: 56px 0 96px;
  }

  .page-about .about-hero__inner {
    grid-template-columns: minmax(72px, 96px) minmax(0, 1fr);
    gap: 48px;
    align-items: start;
  }

  .page-about .about-hero__rail {
    display: flex;
    flex-direction: column;
    align-items: center;
    gap: 18px;
    padding-top: 14px;
    min-height: 320px;
  }

  .page-about .about-hero__badge {
    writing-mode: vertical-rl;
    font-size: 12px;
    letter-spacing: 0.42em;
    color: var(--cyan);
    border: 1px solid var(--line);
    padding: 10px 6px;
  }

  .page-about .about-hero__line {
    flex: 1;
    width: 1px;
    background: linear-gradient(to bottom, rgba(76, 224, 179, 0.5), rgba(76, 224, 179, 0));
  }

  .page-about .about-hero__vlabel {
    writing-mode: vertical-rl;
    transform: rotate(180deg);
    font-size: 12px;
    letter-spacing: 0.3em;
    color: var(--muted);
    white-space: nowrap;
  }

  .page-about .about-split {
    grid-template-columns: minmax(88px, 4fr) minmax(0, 8fr);
    gap: 56px;
  }

  .page-about .about-rail {
    flex-direction: column;
    align-items: center;
    gap: 20px;
    position: sticky;
    top: var(--about-sticky-top);
    height: max-content;
    padding-top: 8px;
  }

  .page-about .about-rail__label {
    writing-mode: vertical-rl;
    transform: rotate(180deg);
    letter-spacing: 0.3em;
  }

  .page-about .about-stages {
    grid-template-columns: repeat(3, minmax(0, 1fr));
    gap: 20px;
  }

  .page-about .about-figure--wide figcaption {
    text-align: right;
  }
}

@media (min-width: 1080px) {
  .page-about .about-hero__lede,
  .page-about .about-body > p,
  .page-about .about-step__text {
    font-size: 17px;
  }
}

@media (prefers-reduced-motion: reduce) {
  .page-about .about-rhythm__item,
  .page-about .about-stage,
  .page-about .about-step__dot {
    transition: none;
  }

  .page-about .about-rhythm__item:hover,
  .page-about .about-stage:hover {
    transform: none;
  }
}