/* ===== ABOUT ===== */
.about { position: relative; }
.about__head { max-width: 1000px; margin-bottom: 80px; }
.about__title { font-size: clamp(40px, 5.5vw, 84px); line-height: 1.18; margin: 16px 0 0; font-weight: 500; letter-spacing: 0.005em; }
.about__title em { font-family: var(--serif-en-display); font-style: italic; font-weight: 500; color: var(--accent); }

.about__lede-block { padding: 36px 0 72px; border-top: 1px solid var(--paper-line); border-bottom: 1px solid var(--paper-line); margin-bottom: 80px; position: relative; }
.about__lede { font-size: clamp(18px, 1.6vw, 22px); line-height: 2.1; color: var(--on-paper); padding-left: 56px; max-width: 980px; font-weight: 400; }
.about__lede em { font-family: var(--serif-en-display); font-style: italic; color: var(--accent-deep); font-weight: 500; }

.about__pillars {
  display: grid;
  grid-template-columns: repeat(3, 1fr);
  gap: 0;
  border-top: 1px solid var(--paper-line);
  border-bottom: 1px solid var(--paper-line);
  margin-bottom: 80px;
}
.about__pillar {
  padding: 48px 36px;
  border-right: 1px solid var(--paper-line);
  display: flex;
  flex-direction: column;
  gap: 16px;
}
.about__pillar:last-child { border-right: none; }
.about__pillar .tag-num { color: var(--chrome); }
.about__pillar h3 { font-family: var(--serif-jp); font-size: 22px; font-weight: 500; margin: 8px 0 4px; line-height: 1.4; }
.about__pillar p { font-family: var(--sans-jp); font-size: 13.5px; line-height: 1.95; color: var(--on-paper-mute); margin: 0; font-feature-settings: "palt"; }
.about__pillar-list { list-style: none; padding: 0; margin: 0; display: flex; flex-direction: column; gap: 12px; }
.about__pillar-list li { display: grid; grid-template-columns: 90px 1fr; gap: 12px; padding-bottom: 10px; border-bottom: 1px solid var(--paper-line); font-size: 13px; color: var(--on-paper-mute); align-items: baseline; font-feature-settings: "palt"; }
.about__pillar-list li:last-child { border-bottom: none; padding-bottom: 0; }
.about__pillar-list li strong { font-family: var(--serif-jp); font-weight: 500; color: var(--on-paper); font-size: 14px; }

.about__manifesto {
  text-align: center;
  max-width: 920px;
  margin: 0 auto;
  padding: 60px 0;
  border-top: 1px solid var(--paper-line);
}
.about__manifesto .kicker-en { color: var(--chrome); display: block; margin-bottom: 24px; }
.about__manifesto-text { font-family: var(--serif-jp); font-weight: 500; font-size: clamp(28px, 3.6vw, 44px); line-height: 1.5; margin: 0 0 24px; letter-spacing: 0.02em; }
.about__manifesto-text em { font-family: var(--serif-en-display); font-style: normal; color: var(--accent); font-size: 1.4em; vertical-align: -0.05em; margin: 0 6px; }
.about__manifesto-sub { font-family: var(--sans-jp); font-size: 14px; line-height: 2; color: var(--on-paper-mute); margin: 0; }

/* ===== AI NATIVE ===== */
.ai-native { position: relative; }
.ai-native__head {
  display: grid;
  grid-template-columns: 1.4fr 1fr;
  gap: 80px;
  align-items: end;
  margin-bottom: 80px;
}
.ai-native__title { font-size: clamp(40px, 5vw, 76px); line-height: 1.2; margin: 16px 0 0; font-weight: 500; }
.ai-native__title em { font-family: var(--serif-jp); font-style: normal; font-weight: 500; color: var(--accent); border-bottom: 1px solid var(--accent); padding-bottom: 4px; }
.ai-native__lede { font-size: 16px; line-height: 2; color: var(--on-paper-mute); margin: 0; }

.ai-native__diagram {
  display: grid;
  grid-template-columns: 1fr auto 1.4fr auto 1fr;
  gap: 24px;
  align-items: stretch;
  padding: 48px;
  border: 1px solid var(--paper-line);
  background: var(--paper);
  margin-bottom: 80px;
}
.ai-native__node {
  display: flex;
  flex-direction: column;
  gap: 8px;
  padding: 28px;
  border: 1px solid var(--paper-line);
  background: var(--paper);
  color: var(--on-paper);
}
.ai-native__node--center {
  border-color: var(--chrome);
  background: linear-gradient(180deg, rgba(31, 30, 29, 0.06), transparent);
}
.ai-native__node .kicker-en { color: var(--chrome); font-size: 11px; }
.ai-native__node strong { font-family: var(--serif-jp); font-weight: 500; font-size: 22px; margin-top: 4px; color: var(--on-paper); }
.ai-native__node em { font-style: normal; font-family: var(--mono); font-size: 12px; color: var(--on-paper-mute); letter-spacing: 0.05em; }
.ai-native__node-list { list-style: none; padding: 16px 0 0; margin: 12px 0 0; border-top: 1px solid var(--paper-line); display: flex; flex-direction: column; gap: 8px; font-size: 13px; color: var(--on-paper); font-family: var(--sans-jp); }
.ai-native__node-list li { padding-left: 14px; position: relative; }
.ai-native__node-list li::before { content: ""; position: absolute; left: 0; top: 0.7em; width: 6px; height: 1px; background: var(--chrome); }

.ai-native__flow { display: flex; flex-direction: column; align-items: center; gap: 8px; min-width: 80px; }
.ai-native__flow-line { width: 100%; height: 1px; background: linear-gradient(90deg, transparent, var(--chrome), transparent); position: relative; }
.ai-native__flow-line::after {
  content: "";
  position: absolute;
  right: -2px;
  top: -3px;
  width: 7px;
  height: 7px;
  border-top: 1px solid var(--chrome);
  border-right: 1px solid var(--chrome);
  transform: rotate(45deg);
}
.ai-native__flow-label { font-family: var(--mono); font-size: 10px; letter-spacing: 0.2em; text-transform: uppercase; color: var(--on-paper-mute); }

.ai-native__pillars {
  display: grid;
  grid-template-columns: repeat(4, 1fr);
  gap: 0;
  border-top: 1px solid var(--paper-line);
  border-bottom: 1px solid var(--paper-line);
}
.ai-native__pillar {
  padding: 40px 28px;
  border-right: 1px solid var(--paper-line);
  display: flex;
  flex-direction: column;
  gap: 12px;
}
.ai-native__pillar:last-child { border-right: none; }
.ai-native__pillar .tag-num { color: var(--chrome); }
.ai-native__pillar h3 { font-family: var(--serif-jp); font-size: 20px; font-weight: 500; margin: 6px 0 4px; line-height: 1.4; color: var(--on-paper); }
.ai-native__pillar p { font-family: var(--sans-jp); font-size: 13px; line-height: 1.95; color: var(--on-paper-mute); margin: 0; font-feature-settings: "palt"; }

@media (max-width: 1100px) {
  .about__pillars { grid-template-columns: 1fr; }
  .about__pillar { border-right: none; border-bottom: 1px solid var(--paper-line); }
  .about__pillar:last-child { border-bottom: none; }
  .ai-native__head { grid-template-columns: 1fr; gap: 32px; }
  .ai-native__diagram { grid-template-columns: 1fr; padding: 32px; }
  .ai-native__flow { flex-direction: row; min-height: 50px; min-width: auto; }
  .ai-native__flow-line { width: 1px; height: 50px; background: linear-gradient(180deg, transparent, var(--chrome), transparent); }
  .ai-native__flow-line::after { right: auto; left: -3px; top: auto; bottom: -2px; transform: rotate(135deg); }
  .ai-native__pillars { grid-template-columns: 1fr 1fr; }
  .ai-native__pillar { border-right: 1px solid var(--paper-line); border-bottom: 1px solid var(--paper-line); }
  .ai-native__pillar:nth-child(2n) { border-right: none; }
  .ai-native__pillar:nth-last-child(-n+2) { border-bottom: none; }
}
@media (max-width: 720px) {
  .about__head { margin-bottom: 48px; }
  .about__title { font-size: clamp(28px, 7vw, 40px); line-height: 1.28; }
  .about__lede-block { padding: 24px 0 36px; margin-bottom: 48px; }
  .about__lede { padding-left: 0; font-size: 15px; line-height: 1.95; }
  .about__pillars { margin-bottom: 48px; }
  .about__pillar { padding: 32px 24px; }
  .about__pillar h3 { font-size: 19px; }
  .about__pillar p { font-size: 13px; }
  .about__pillar-list li { grid-template-columns: 70px 1fr; gap: 10px; font-size: 12px; }

  .about__manifesto { padding: 40px 0; }
  .about__manifesto-text { font-size: clamp(20px, 5.5vw, 28px); }
}
@media (max-width: 700px) {
  .ai-native__pillars { grid-template-columns: 1fr; }
  .ai-native__pillar { border-right: none; }
  .ai-native__pillar:nth-child(n) { border-right: none; }
  .ai-native__node { padding: 20px; }
  .ai-native__diagram { padding: 24px; gap: 16px; }
}