:root{color-scheme:dark;font-family:ui-sans-serif,system-ui,-apple-system,BlinkMacSystemFont,"Segoe UI",sans-serif;color:#f5eefb;background:#100a19;font-synthesis:none}
*{box-sizing:border-box}body{margin:0;background:radial-gradient(ellipse 100% 600px at 80% 0,#42206480,transparent),#100a19}a{color:#dfbaff;text-underline-offset:4px}a:hover{color:#fff}a:focus-visible,summary:focus-visible{outline:3px solid #d8a4ff;outline-offset:5px;border-radius:4px}
.skip{position:absolute;left:16px;top:8px;padding:12px;background:#251537;transform:translateY(-180%);z-index:5}.skip:focus{transform:none}
.site{max-width:1180px;margin:auto;min-height:86px;padding:16px 28px;display:flex;gap:28px;align-items:center;justify-content:space-between;border-bottom:1px solid #4e345e}.brand{display:flex;align-items:center;gap:10px;color:#fff;text-decoration:none;font-size:21px;font-weight:850;letter-spacing:.09em}
.site nav{display:flex;gap:24px;align-items:center;font-size:14px}.site nav a{padding:10px 0;text-decoration:none}.brand img{object-fit:contain}
main{max-width:1180px;margin:0 auto;padding:28px 28px 60px}.breadcrumbs{display:flex;flex-wrap:wrap;gap:10px;font-size:13px;line-height:1.7;color:#c5b3d4;margin-bottom:34px}.breadcrumbs a{padding:4px 0}
.hero{max-width:900px;margin:0 0 36px}.eyebrow{font-size:11px;letter-spacing:.11em;font-weight:800;color:#dca8ff;text-transform:uppercase}.hero h1{font-size:clamp(30px,4.5vw,52px);line-height:1.13;letter-spacing:-.035em;margin:16px 0 22px;text-wrap:balance}
.lead{font-size:19px;line-height:1.75;color:#e4d6ef}.byline{font-size:13px;line-height:1.7;color:#c8b7d5}.byline a{color:inherit}
.layout{display:grid;grid-template-columns:minmax(0,1fr) 265px;gap:30px;align-items:start}.content{min-width:0}.content section{scroll-margin-top:22px;margin:0 0 24px;padding:28px;border:1px solid #4a315e;border-radius:20px;background:linear-gradient(125deg,#25172fd9,#181120eb)}
h2{font-size:24px;line-height:1.3;letter-spacing:-.02em;margin:0 0 18px}h3{font-size:17px;line-height:1.5;margin:24px 0 10px}p,li{font-size:16px;line-height:1.85;color:#e1d5eb}p{margin:0 0 17px}p:last-child{margin-bottom:0}ul{padding-left:24px}li{margin-bottom:12px}li::marker{color:#c383ff}
.example{border-top:2px solid #a65ee5!important}.prompt{font-size:18px;color:#fff;padding:18px 20px;background:#120c1bb3;border-radius:13px;border:1px solid #4c3260;margin-bottom:24px}
.solution{list-style:none;counter-reset:steps;padding:0;margin:0}.solution>li{counter-increment:steps;position:relative;padding-left:45px;margin:0 0 23px}.solution>li:before{content:counter(steps);position:absolute;left:0;top:1px;width:29px;height:29px;display:grid;place-items:center;font-size:13px;font-weight:800;background:#6835a3;color:#fff;border-radius:10px}.solution h3{margin:0 0 8px}.solution p{margin-bottom:10px}
.equation{max-width:100%;overflow:auto;padding:12px 6px;color:#fff}.equation math{margin:0;font-size:1.18em}math{font-family:"Cambria Math","STIX Two Math",math;font-size:1.06em}
.answer{border:1px solid #4d9d89;border-radius:13px;padding:16px 20px;background:#15352f80;margin:12px 0 16px}.answer>span{display:block;font-size:11px;font-weight:800;color:#9ce8d2;text-transform:uppercase;letter-spacing:.09em;margin-bottom:8px}.answer p{color:#e5fff7;font-weight:650;font-size:18px;margin:0}.explanation{font-size:14px;color:#d2c2e0}
details>summary{cursor:pointer;min-height:46px;padding:12px 0;color:#dfbaff;font-weight:750;font-size:15px;line-height:1.6}details[open]>summary{margin-bottom:22px}
.takeaway{padding:20px;border-left:3px solid #b173ee;background:#6f39962e;border-radius:0 12px 12px 0;margin-top:22px}.takeaway h3{color:#e0b9ff;margin:0 0 8px}.takeaway p{margin:0}
aside{position:sticky;top:24px;display:grid;gap:20px}aside>nav,aside>.practice{padding:22px;background:#281a35e6;border:1px solid #57366d;border-radius:18px}aside h2{font-size:17px;line-height:1.5}aside nav a{display:block;padding:9px 0;font-size:14px;text-decoration:none}aside p{font-size:14px;line-height:1.7}.practice>a{display:block;font-size:14px;margin-top:15px}.practice .cta{padding:13px 14px;text-align:center;border-radius:10px;background:linear-gradient(120deg,#a936d6,#7633dc);color:#fff;font-weight:750;text-decoration:none}
.related{margin-top:40px}.related>div{display:grid;grid-template-columns:repeat(2,minmax(0,1fr));gap:18px}.related a{display:flex;flex-direction:column;text-decoration:none;border:1px solid #57366d;border-radius:18px;background:#21152e;padding:24px}.related h3{color:#fff;margin:0 0 12px;font-size:20px}.related p{font-size:14px}.related span{font-size:14px;font-weight:700;margin-top:auto}
footer{max-width:1124px;margin:auto;padding:30px 0 38px;border-top:1px solid #4e345e}footer>a{font-weight:850;letter-spacing:.1em;text-decoration:none}footer p{font-size:13px;color:#c8b7d5;margin:14px 0}footer nav{display:flex;gap:24px;flex-wrap:wrap}footer nav a{font-size:13px;padding:8px 0}
@media(max-width:850px){.layout{grid-template-columns:1fr}aside{position:static;grid-row:1;grid-template-columns:1fr 1fr}.site{padding-inline:22px}main{padding-inline:22px}footer{margin-inline:22px}.hero h1{font-size:38px}}
@media(max-width:560px){.site{gap:12px;flex-wrap:wrap;padding:18px}.site nav{gap:22px}.site nav a{font-size:13px}.brand{font-size:19px}main{padding:22px 16px 40px}.hero h1{font-size:31px}.lead{font-size:17px}.layout{gap:20px}aside{grid-template-columns:1fr}aside>nav{display:none}.content section{padding:23px 18px}.prompt{padding:15px;font-size:17px}.solution>li{padding-left:38px}.solution>li:before{width:26px;height:26px}.answer{padding:16px}.related>div{grid-template-columns:1fr}h2{font-size:22px}p,li{font-size:16px}.breadcrumbs{font-size:12px;margin-bottom:26px}footer{margin-inline:18px}}
@media print{body{background:#fff;color:#111}.site nav,aside,.related,footer,.skip{display:none}.layout{display:block}main{max-width:none}.content section,.prompt{background:#fff;border-color:#aaa;break-inside:avoid}.hero h1,h2,h3,p,li,.prompt,.equation{color:#111}.answer{background:#eee;border-color:#777}.answer p,.answer span{color:#111}a{color:#111}.example{border-top-color:#777!important}}