body{margin:0;background:#070b15;color:#eef4ff;font-family:Inter,system-ui,sans-serif}
.shell{width:min(980px,calc(100% - 2rem));margin:1rem auto;display:grid;gap:.8rem}
.panel{border:1px solid rgba(140,170,220,.35);background:#0f1629;border-radius:14px;padding:.9rem}
.kicker{margin:0;color:#66e2ff;font-size:12px;letter-spacing:.12em}
h1{margin:.35rem 0;font-size:clamp(24px,4.6vw,40px)}
.subtitle{margin:0;color:#9fb3d8;line-height:1.55}
.chips,.map,.tabs{display:flex;gap:.45rem;flex-wrap:wrap;margin-top:.65rem}
.chip,.node,.tab{border:1px solid rgba(140,170,220,.35);background:#141f38;color:#e6efff;border-radius:999px;padding:.3rem .65rem;font-size:.8rem}
.node{cursor:default}
.tab{cursor:pointer}
.tab.active{background:#66e2ff;color:#041320;border-color:transparent;font-weight:600}
.chapter-body{margin-top:.65rem;border:1px solid rgba(140,170,220,.35);background:#121d34;border-radius:10px;padding:.7rem;line-height:1.58}
.chapter-body h3{margin:.1rem 0 .35rem}
.chapter-body p{margin:.35rem 0;color:#dce8ff}
.grid-2{display:grid;grid-template-columns:1fr 1fr;gap:.7rem}
.cards{display:grid;gap:.5rem;margin-top:.55rem}
.card{border:1px solid rgba(140,170,220,.35);background:#121d34;border-radius:10px;padding:.6rem}
.card h3{margin:0 0 .25rem;color:#66e2ff;font-size:.92rem}
.card p{margin:0;color:#dce8ff;line-height:1.5;font-size:.9rem}
@media(max-width:820px){.grid-2{grid-template-columns:1fr}}