:root{color-scheme:light;--ink:#292b2d;--brass:#916e22;--paper:#fff;--soft:#f4f1e9}*{box-sizing:border-box}body{margin:0;background:var(--soft);color:var(--ink);font:16px/1.7 system-ui,sans-serif}main{max-width:940px;margin:auto;padding:18px}header{margin-bottom:22px}h1{font-size:28px;margin:12px 0 0}h2{font-size:22px;margin-top:0}p{margin:8px 0 14px}a{color:#755610;text-underline-offset:3px}.card{background:var(--paper);border:1px solid #d9d2c0;border-radius:14px;padding:20px;margin-bottom:18px}.selectors{display:grid;grid-template-columns:1fr 1fr;gap:12px}label{display:block;font-weight:600}select,textarea,input{font:inherit;color:inherit;background:white;border:1px solid #aaa;border-radius:8px;padding:10px;width:100%;margin:5px 0 12px;min-width:0}button{font:inherit;border:1px solid #b6ac90;border-radius:8px;padding:9px 12px;background:#faf8f2;color:inherit;cursor:pointer;min-height:42px}button:disabled{opacity:.45;cursor:default}button:focus-visible,a:focus-visible,select:focus-visible,textarea:focus-visible,input:focus-visible{outline:3px solid #ac841f;outline-offset:2px}.actions{display:flex;flex-wrap:wrap;gap:8px;margin-top:14px}.steps{display:flex;gap:7px;overflow-x:auto;padding:3px 0 10px;margin-bottom:10px}.steps button{flex:0 0 auto;font-size:14px}.steps .active,#learnCheck{background:var(--brass);color:white;border-color:var(--brass)}pre{margin:12px 0;padding:16px;border-radius:10px;background:#20262c;color:#e8f2ee;white-space:pre-wrap;overflow-wrap:anywhere;font:14px/1.75 ui-monospace,monospace;tab-size:4;max-height:420px;overflow:auto}textarea{min-height:170px;resize:vertical;font:14px/1.7 ui-monospace,monospace;tab-size:4;white-space:pre;overflow:auto}#learnFeedback{padding:10px;border-radius:8px;white-space:pre-wrap}#learnFeedback:empty{display:none}#learnFeedback.good{color:#165c35;background:#e8f5ec}#learnFeedback.bad{color:#8e2a24;background:#fff0ed}.explanation{padding:14px;background:#f8f5ed;border-left:3px solid #b18a39;white-space:pre-wrap;overflow-wrap:anywhere}.topic-nav{justify-content:space-between;border-top:1px solid #eee;padding-top:14px}.changes li{overflow-wrap:anywhere}#learnSaveStatus{font-size:13px;color:#6e5e3b}.line-notes li{margin:8px 0}.line-notes code{background:#f2efe7;padding:2px 4px;overflow-wrap:anywhere}#learnProgress{font-weight:600;font-size:14px}details{margin-top:14px}summary{cursor:pointer;font-weight:600}@media(max-width:600px){main{padding:12px}.card{padding:16px}h1{font-size:24px}h2{font-size:19px}.actions button{flex:1 1 auto;font-size:14px}pre{font-size:13px;padding:12px}textarea{font-size:14px}.steps button{font-size:13px}#learnIntro{font-size:14px}}