:root{--scale:1;--green:#1d5b45;--green2:#2c7b5b;--light:#edf5f0;--ink:#17221d;--muted:#65736c;--line:#dfe7e2;--paper:#fff;--bg:#fafcfb}*{box-sizing:border-box}html{scroll-behavior:smooth}body{margin:0;font-family:Arial,sans-serif;color:var(--ink);background:var(--bg);font-size:calc(16px * var(--scale));line-height:1.65}button,input,select{font:inherit}.app-header{display:flex;align-items:center;gap:22px;padding:15px 4vw;background:#fff;border-bottom:1px solid var(--line);position:sticky;top:0;z-index:20}.brand{font-weight:800;color:var(--green);text-decoration:none;white-space:nowrap}.main-nav{display:flex;gap:14px;flex:1;overflow:auto}.main-nav a{color:var(--ink);text-decoration:none;padding:6px 2px;border-bottom:2px solid transparent}.main-nav a.active{color:var(--green);border-color:var(--green)}.font-controls{display:flex;gap:5px}.font-controls button,.btn{border:1px solid #ccd8d1;background:#fff;border-radius:8px;padding:7px 10px;cursor:pointer}.btn.primary{background:var(--green);color:#fff;border-color:var(--green)}.app-main{min-height:75vh}.hero{padding:58px 7vw;background:var(--light)}.eyebrow{font-size:.82em;font-weight:800;color:var(--green);text-transform:uppercase;letter-spacing:.06em}.hero h1{font-size:2.5em;line-height:1.1;margin:.3em 0}.hero p{max-width:760px}.page{max-width:1180px;margin:auto;padding:34px 5vw}.page h1{margin:.1em 0}.muted{color:var(--muted)}.grid{display:grid;grid-template-columns:repeat(auto-fit,minmax(235px,1fr));gap:16px}.card{background:var(--paper);border:1px solid var(--line);border-radius:14px;padding:20px}.card h2,.card h3{margin-top:0}.tag{display:inline-block;background:var(--light);color:var(--green);border-radius:999px;padding:4px 9px;font-size:.78em}.metric{font-size:2em;font-weight:800;color:var(--green)}.library-tools{display:flex;gap:10px;flex-wrap:wrap;margin-bottom:18px}.library-tools input,.library-tools select{padding:9px 11px;border:1px solid var(--line);border-radius:8px;background:#fff;min-width:260px}.concept-list{display:grid;gap:9px}.concept-row{display:grid;grid-template-columns:80px 1fr auto;align-items:center;gap:12px;background:#fff;border:1px solid var(--line);border-radius:10px;padding:13px 15px}.concept-row a{color:var(--ink);text-decoration:none;font-weight:700}.concept-row a:hover{color:var(--green)}.learn-state{font-size:.75em;color:var(--green);background:var(--light);border-radius:999px;padding:4px 8px}.reader{max-width:850px;margin:auto;background:#fff;border:1px solid var(--line);border-radius:14px;padding:32px}.learner-reader{max-width:800px}.concept-meta{display:flex;gap:10px;align-items:center;flex-wrap:wrap;color:var(--muted);font-size:.86em;margin-bottom:22px}.lead-copy{font-size:1.18em;line-height:1.75;color:#33473e}.reader h2{margin-top:30px}.example-box{background:#f6f9f7;border-left:3px solid var(--green2);padding:16px 18px;border-radius:0 10px 10px 0}.caution-box{background:#fff8e8;border-left:3px solid #d3a33c;padding:14px 17px;margin:24px 0}.caution-box p{margin:.3em 0 0}.learning-steps li{margin:7px 0}.reader-actions{display:flex;gap:8px;flex-wrap:wrap;margin-top:18px}.context{border-bottom:2px dotted var(--green);cursor:pointer}.glossary{display:grid;gap:12px}.gloss-entry{background:#fff;border-bottom:1px solid var(--line);padding:15px 4px}.glossary dt{font-weight:800;color:var(--green);font-size:1.03em}.glossary dd{margin:5px 0 0;max-width:850px}.gloss-more{font-size:.84em;margin-top:5px}.gloss-more a{color:var(--green)}.lesson-section{padding:18px 0;border-top:1px solid var(--line)}.check{background:#f8faf9;border:1px solid var(--line);border-radius:10px;padding:15px;margin:12px 0}.check label{display:block;margin:7px 0}.feedback{margin-top:8px;font-weight:700}.app-footer{padding:24px 5vw;color:var(--muted);border-top:1px solid var(--line)}@media(max-width:760px){.app-header{flex-wrap:wrap}.main-nav{order:3;width:100%}.hero h1{font-size:2em}.concept-row{grid-template-columns:65px 1fr}.concept-row .learn-state{grid-column:2}.reader{padding:22px}.library-tools input,.library-tools select{min-width:100%}}