:root{--ink:#193e3a;--text:#304641;--muted:#687770;--paper:#f7f6f0;--line:#dce1d8;--accent:#cce19f}*{box-sizing:border-box}body{margin:0;background:var(--paper);color:var(--text);font:16px/1.65 Arial,sans-serif}main{max-width:1160px;margin:auto;padding:32px 24px 64px}a{color:var(--ink)}h1{font:clamp(34px,5vw,60px)/1.1 Georgia,serif;color:var(--ink);max-width:900px;margin:28px 0 18px}h2{color:var(--ink);font-size:24px}h3{line-height:1.4}small,.muted{color:var(--muted)}.eyebrow{font-size:11px;letter-spacing:1.5px;text-transform:uppercase;margin-top:32px}.grid{display:grid;grid-template-columns:repeat(3,1fr);gap:16px;margin:32px 0}.card{border:1px solid var(--line);background:#fff;border-radius:8px;padding:23px 24px 19px;min-height:214px;display:flex;flex-direction:column;text-decoration:none}.card[href]:hover{transform:translateY(-3px);border-color:#9bb28a;box-shadow:0 8px 24px #193e3a12}.card-top{display:flex;justify-content:space-between;gap:12px;margin-bottom:20px;font-size:10px;letter-spacing:1.5px;text-transform:uppercase}.available{color:#4f712f;font-size:9px}.card h3{font-size:18px;font-weight:500;margin:0 0 23px}.card-bottom{border-top:1px solid #edf0e8;padding-top:14px;margin-top:auto;display:flex;justify-content:space-between;font-size:11px;color:var(--muted)}nav,.actions{display:flex;gap:10px;flex-wrap:wrap;margin:24px 0}button,.button,select,input{font:inherit}button,.button{display:inline-block;padding:10px 18px;border:1px solid var(--line);border-radius:6px;background:#fff;color:var(--ink);cursor:pointer;text-decoration:none}button.primary,button[aria-pressed=true],button[aria-current=page]{background:var(--ink);color:#fff}button:disabled{opacity:.5;cursor:default}button:hover:not(:disabled),.button:hover{border-color:#6c8a62}button:focus-visible,a:focus-visible,select:focus-visible,input:focus-visible{outline:3px solid #71964a;outline-offset:3px}.panel,details{border:1px solid var(--line);border-radius:8px;background:white;padding:24px;margin:18px 0}summary{cursor:pointer;font-weight:bold;color:var(--ink)}details h3{font-size:17px}li{margin-bottom:9px}img{max-width:100%;height:auto}figure{margin:24px 0}figcaption{font-size:13px;color:var(--muted)}.flash{min-height:220px;display:grid;place-items:center;text-align:center;font-size:22px;padding:30px;width:100%}.flash small{display:block;font-size:13px;margin-top:18px}.options{display:grid;gap:12px}.options button{text-align:left}.correct{border-color:#426b30;background:#f0f7e7}.incorrect{border-color:#ac4f40;background:#fff1ed}.feedback{padding:16px;border-left:4px solid #71964a;background:#f0f3e9;margin:18px 0}.settings{display:flex;gap:20px;flex-wrap:wrap;align-items:end}.settings label{display:grid;gap:6px}select,input[type=search]{padding:10px;border:1px solid var(--line);border-radius:5px;background:#fff;max-width:100%}footer{margin-top:40px;padding-top:20px;border-top:1px solid var(--line);font-size:13px;color:var(--muted)}[hidden]{display:none!important}@media(max-width:850px){.grid{grid-template-columns:repeat(2,1fr)}}@media(max-width:590px){main{padding:24px 16px 44px}.grid{grid-template-columns:1fr}.panel,details{padding:18px}h1{font-size:36px}}

/* Shared chapter-card proportions used by the main study room. */
.grid{display:grid;grid-template-columns:repeat(3,1fr);gap:16px}.card{border:1px solid var(--line);background:#fff;border-radius:8px;padding:23px 24px 19px;text-decoration:none;min-height:214px;display:flex;flex-direction:column;transition:transform .18s,border-color .18s,box-shadow .18s}.card[href]:hover{transform:translateY(-3px);border-color:#9bb28a;box-shadow:0 6px 20px #153c3010}.card-top{display:flex;align-items:center;justify-content:space-between;margin-bottom:20px}.chapter-num{font-size:10px;text-transform:uppercase;letter-spacing:1.5px;color:var(--muted)}.available{font-size:9px;color:#50734d;display:flex;align-items:center;gap:5px}.available .dot{width:4px;height:4px}.card h3{color:var(--ink);font-size:18px;font-weight:500;letter-spacing:-.5px;line-height:1.3;margin:0 0 23px;max-width:260px}.card-bottom{border-top:1px solid #edf0e8;padding-top:14px;margin-top:auto;display:flex;align-items:center;justify-content:space-between;font-size:10px;color:var(--muted)}.arrow{font-size:19px;color:var(--ink);line-height:1}
.card-top{gap:12px;letter-spacing:normal;text-transform:none}.chapter-num{white-space:nowrap}.card-top>.available{letter-spacing:normal;text-transform:none}.card[aria-disabled=true]{opacity:.72}.card[aria-disabled=true]:hover{transform:none;box-shadow:none;border-color:var(--line)}
@media(max-width:850px){.grid{grid-template-columns:repeat(2,1fr)}}@media(max-width:590px){.grid{grid-template-columns:1fr;gap:12px}.card{min-height:174px;padding:20px}.card h3{max-width:none;margin-bottom:18px}.card-top{margin-bottom:15px}}
@media(prefers-reduced-motion:reduce){.card{transition:none}}

.available .dot{display:inline-block;border-radius:50%;background:#56825a}