*{box-sizing:border-box}html{scroll-behavior:smooth}body{margin:0;background:radial-gradient(ellipse at 75% -10%,#293f77 0,transparent 35%),radial-gradient(ellipse at 2% 40%,#18295c 0,transparent 50%),#080d21;color:#f0f5ff;font-family:system-ui,-apple-system,"Segoe UI",sans-serif;line-height:1.7}a{color:#7df0df;text-underline-offset:3px}a:hover{color:#b7fff5}.shell{max-width:1150px;margin:0 auto;padding:0 23px}.skip{position:absolute;transform:translateY(-200%);background:white;color:black;padding:6px;z-index:20}.skip:focus{transform:none}.site-top{border-bottom:1px solid #8dabdd2b;background:#0e1733bf}.topline{display:flex;justify-content:space-between;gap:24px;align-items:center;min-height:76px;flex-wrap:wrap}.logo{text-decoration:none;font-size:19px;color:#fff;font-weight:900;letter-spacing:-.8px}.logo span{color:#60efdc}.topline nav{display:flex;flex-wrap:wrap;gap:11px 20px;font-size:13px}.topline nav a{text-decoration:none;color:#bfd4ea}.crumb{padding:25px 0 12px;color:#9db4d2;font-size:12px}.crumb span{padding:0 7px}.intro{padding:22px 0 27px;max-width:850px}.eyebrow{font-size:11px;letter-spacing:1.8px;font-weight:850;color:#71f4da}.intro h1{font-size:clamp(35px,5vw,55px);letter-spacing:-1.9px;line-height:1.11;margin:10px 0 20px}.lead{color:#bed0e7;font-size:18px}.primary{display:inline-block;padding:11px 18px;border-radius:13px;text-decoration:none;background:linear-gradient(115deg,#5af0db,#92aaff);color:#09223e;font-size:14px;font-weight:850;margin:10px 0}.cols{display:grid;grid-template-columns:minmax(0,1fr) 320px;gap:45px;align-items:start;margin:30px 0}.lesson section{margin-bottom:32px}.lesson h2,.box h2,.related h2{font-size:24px;line-height:1.25;letter-spacing:-.5px;margin:0 0 11px}.lesson p,.box p{color:#c4d1e7;margin:0 0 12px}.lesson h3{font-size:17px;margin:19px 0 4px}.box{background:#132245eb;border:1px solid #6179a757;padding:21px;border-radius:20px;margin-bottom:18px}.box h2{font-size:21px}.missions{padding-left:20px}.missions li{margin-bottom:10px}.fine{font-size:12px;color:#a8badd!important}.related{border-top:1px solid #627aa64d;padding:24px 0 50px}.related-links{display:flex;gap:10px;flex-wrap:wrap}.related-links a{display:inline-block;background:#1a2a4c;border:1px solid #324c70;padding:8px 12px;border-radius:9px;font-size:13px;text-decoration:none}.foot{border-top:1px solid #52668d66;padding:22px 0 40px;color:#b0bed8;font-size:12px}.foot span{display:block;margin-top:4px}a:focus-visible{outline:3px solid #ffd78e;outline-offset:3px}@media(max-width:840px){.cols{grid-template-columns:1fr;gap:10px}.topline{padding-top:14px;padding-bottom:15px}.intro{padding-top:11px}.lesson h2{font-size:22px}}@media(prefers-reduced-motion:reduce){html{scroll-behavior:auto}}