:root{--ink:#172522;--paper:#f4f5ef;--line:#d8ded7;--muted:#6b7770;--green:#1d6d5c;--mint:#d9eadc;--gold:#f0d27a}*{box-sizing:border-box}html{scroll-behavior:smooth}body{margin:0;background:var(--paper);color:var(--ink);font-family:Arial,sans-serif}a{text-decoration:none;color:inherit}.hero{max-width:1200px;margin:auto;padding:25px 6vw 95px}nav{display:flex;justify-content:space-between;align-items:center;border-bottom:1px solid var(--line);padding-bottom:22px;font-size:12px;letter-spacing:.12em}.brand{font-weight:700}.brand em{font-style:normal;color:var(--muted);font-weight:400}.hero-grid{display:grid;grid-template-columns:1fr 1fr;gap:60px;align-items:center;padding-top:85px}.eyebrow{font-size:10px;letter-spacing:.18em;color:#5e7469;font-weight:700}.hero h1{font:normal clamp(55px,7vw,92px)/.9 Georgia;margin:20px 0;letter-spacing:-.06em}.hero h1 i,h2 i{color:var(--green)}.lede{font:18px/1.6 Arial;color:var(--muted);max-width:520px;margin-bottom:32px}.button{display:inline-block;background:var(--green);color:#fff;padding:15px 20px;font-size:12px;letter-spacing:.08em}.hero-art{height:380px;display:flex;justify-content:center;align-items:center;position:relative}.orb{width:190px;height:190px;border-radius:50%;background:var(--green);color:white;display:flex;flex-direction:column;align-items:center;justify-content:center;font:italic 28px Georgia}.orb small{font:10px Arial;color:#d9eadc;margin-top:8px}.node{position:absolute;background:var(--paper);border:1px solid var(--line);padding:10px;font-size:10px;letter-spacing:.1em}.n1{top:18%;left:12%;color:#a67316}.n2{top:30%;right:6%;color:var(--green)}.n3{bottom:15%;right:20%;color:#bd6745}.intro,.curriculum,.workspace{max-width:1200px;margin:auto;padding:85px 6vw}.intro{border-top:1px solid var(--line);display:grid;grid-template-columns:1fr 1fr;gap:60px}.intro h2{font:normal 46px/.98 Georgia;margin:15px 0}.intro>p:last-child{color:var(--muted);line-height:1.7;max-width:420px}.section-head,.workspace-head{display:flex;justify-content:space-between;align-items:end;gap:30px}.section-head h2,.workspace-head h2{font:normal 50px Georgia;margin:15px 0 0}.filters{display:flex;gap:8px;border-bottom:1px solid var(--line)}.filters button{border:0;background:none;padding:12px 15px;color:var(--muted);cursor:pointer}.filters button.active{color:var(--ink);border-bottom:2px solid var(--green)}.cards{display:grid;grid-template-columns:repeat(3,1fr);gap:13px;margin-top:45px}.card{text-align:left;background:transparent;border:1px solid var(--line);padding:22px;min-height:190px;cursor:pointer;position:relative;color:var(--ink)}.card:hover,.card.selected{background:#e7eee6;border-color:#8bad9a;transform:translateY(-2px)}.pill{display:inline-block;background:var(--mint);padding:6px 8px;font-size:10px;letter-spacing:.08em}.card h3{font:normal 25px Georgia;margin:28px 0 8px}.card p{font-size:13px;line-height:1.5;color:var(--muted);max-width:270px}.arrow{position:absolute;right:20px;bottom:18px;color:var(--green);font-size:22px}.workspace{padding-top:20px;background:#e8eee7}.workspace-head{padding-bottom:30px;border-bottom:1px solid #c7d5c9}.workspace-head h2{font-size:46px}.lesson-grid{display:grid;grid-template-columns:1.2fr .8fr;gap:80px;padding:45px 0}.outcome{font:23px/1.45 Georgia;color:var(--green);max-width:650px}.loop{display:flex;gap:12px;align-items:center;margin:30px 0;flex-wrap:wrap}.loop span{background:#f4f5ef;border:1px solid #b9cdbd;padding:12px;font:italic 16px Georgia}.loop b{color:var(--green)}.actions{display:flex;gap:22px;align-items:center;margin-top:35px}.text-link{color:var(--green);border-bottom:1px solid var(--green);font-size:12px}.source{display:flex;gap:12px;border-bottom:1px solid #c7d5c9;padding:12px 0;font-size:13px}.source span{color:var(--green)}.quiz-link{display:block;color:var(--green);font-weight:700;font-size:13px;margin-top:30px}footer{background:var(--ink);color:#d9eadc;padding:25px 6vw;display:flex;justify-content:space-between;font-size:11px;letter-spacing:.1em}footer a{color:#abd1b8}@media(max-width:760px){.hero-grid,.intro,.lesson-grid{grid-template-columns:1fr}.hero-art{height:280px}.cards{grid-template-columns:1fr}.section-head,.workspace-head{display:block}.filters{margin-top:25px;overflow:auto}.actions{flex-wrap:wrap}footer{gap:15px;flex-wrap:wrap}}
.progress{grid-column:1/-1;color:var(--muted);font-size:11px;letter-spacing:.12em;text-transform:uppercase}.complete{margin-top:30px;border:1px solid var(--green);background:transparent;color:var(--green);padding:11px 15px;cursor:pointer}.complete:hover{background:var(--mint)}
.lesson-tabs{display:flex;gap:10px;border-bottom:1px solid #c7d5c9;margin-top:30px}.lesson-tabs button{border:0;background:transparent;padding:13px 16px;color:var(--muted);cursor:pointer}.lesson-tabs button.active{color:var(--ink);border-bottom:2px solid var(--green)}
.oneplus-brand{display:flex;align-items:center;gap:12px;margin-top:18px;padding-top:15px;border-top:1px solid rgba(255,255,255,.2);font-size:10px;letter-spacing:.06em}.oneplus-brand img{width:32px;height:32px;object-fit:contain;background:#fff;border-radius:50%;padding:3px}.oneplus-brand a{color:#d9eadc}.oneplus-brand span{color:#b8cfc0}@media(max-width:760px){.oneplus-brand{flex-wrap:wrap}}