:root{color-scheme:dark;--bg:#10141d;--panel:#191f2b;--ink:#edf0f6;--dim:#aeb8ca;--line:#343e50;--accent:#f2b62d;--teal:#61dabd;font-family:system-ui,-apple-system,BlinkMacSystemFont,"Segoe UI",sans-serif;font-size:16px}
*{box-sizing:border-box}body{margin:0;background:var(--bg);color:var(--ink);line-height:1.6}a{color:var(--teal);text-underline-offset:.25em}a:hover{color:var(--ink)}button,a{-webkit-tap-highlight-color:transparent}a:focus-visible,button:focus-visible,summary:focus-visible{outline:3px solid var(--accent);outline-offset:5px}.wrap{max-width:1060px;margin:auto;padding:0 max(22px,env(safe-area-inset-right)) 30px max(22px,env(safe-area-inset-left))}header{display:flex;align-items:center;justify-content:space-between;gap:1rem;min-height:88px;border-bottom:1px solid var(--line)}header a{display:inline-flex;align-items:center;min-height:44px}.brand{font-weight:650;color:var(--ink);text-decoration:none;font-size:1.1rem}nav a{font-size:.95rem}.lesson-head{padding:32px 0 26px}.eyebrow,.section-label{font-family:ui-monospace,SFMono-Regular,monospace;font-size:.88rem;letter-spacing:.09em;text-transform:uppercase;color:var(--accent);margin:0 0 8px}h1{font-family:Georgia,serif;font-size:clamp(2.4rem,8vw,3.8rem);line-height:1.15;font-weight:400;letter-spacing:-.035em;margin:0}h2{font-size:1.35rem;line-height:1.35;margin:0 0 18px}h3{font-size:1.15rem;line-height:1.4;margin:0 0 5px}p{margin:6px 0 12px}.muted,.composer{color:var(--dim)}.layout{display:grid;gap:30px;align-items:start}.technique{background:var(--panel);border-top:3px solid var(--accent);padding:24px;border-radius:0 0 12px 12px}.exercise{padding:16px 0;border-bottom:1px solid var(--line)}.exercise:first-of-type{padding-top:0}.exercise:last-child{border-bottom:0;padding-bottom:0}.piece{padding:22px 0;border-bottom:1px solid var(--line)}.piece:first-of-type{padding-top:0}.book{font-family:ui-monospace,SFMono-Regular,monospace;font-size:.88rem;color:var(--teal);margin-bottom:7px}.pages{font-size:.95rem;color:var(--dim);margin:3px 0 7px}.hand{display:inline-block;border:1px solid var(--line);border-radius:5px;padding:2px 9px;font-size:.88rem;color:var(--ink);margin:4px 0}.notes{margin:8px 0 0;padding-left:20px}.notes li+li{margin-top:5px}.teacher{margin-top:24px;border-left:3px solid var(--teal);padding-left:20px}.teacher p{font-family:Georgia,serif;font-size:1.4rem;margin:0}.teacher h2{font-family:ui-monospace,monospace;font-size:.88rem;color:var(--dim);font-weight:400;margin-bottom:10px}.review{border:1px solid var(--accent);border-radius:10px;padding:20px;margin-bottom:26px}.review h2{color:var(--accent)}.review li{margin:12px 0;overflow-wrap:anywhere}.helpers{margin-top:32px}.helper{background:var(--panel);padding:22px;border-radius:12px;margin-bottom:16px}.helper img,.helper canvas{display:block;max-width:100%;height:auto;border-radius:6px;background:white;margin-top:14px}.history-list{list-style:none;padding:0}.history-list a{display:flex;justify-content:space-between;flex-wrap:wrap;gap:12px;padding:22px 0;border-bottom:1px solid var(--line);font-size:1.1rem}.history-list span{color:var(--accent);font-size:.9rem}details{margin-top:26px;border-top:1px solid var(--line);padding-top:16px}summary{cursor:pointer;min-height:44px;color:var(--dim)}pre{white-space:pre-wrap;overflow-wrap:anywhere;font:inherit;color:var(--dim)}footer{color:var(--dim);font-family:Georgia,serif;font-style:italic;font-size:1rem;margin-top:46px;padding-top:22px;border-top:1px solid var(--line)}button{font:inherit;color:var(--bg);background:var(--accent);border:0;border-radius:6px;padding:10px 18px;min-height:44px;cursor:pointer}.error{padding:32px 0}.back{display:inline-flex;align-items:center;min-height:44px;margin-top:12px}.extra{margin-top:24px}.extra h2{font-size:1.1rem}.extra p{color:var(--dim)}
@media(min-width:760px){.layout{grid-template-columns:minmax(260px,.85fr) minmax(0,1.5fr);gap:48px}.lesson-head{padding:40px 0 36px}.technique{padding:28px}.piece h3{font-size:1.3rem}}
@media(prefers-reduced-motion:no-preference){main{animation:appear .2s ease-out}@keyframes appear{from{opacity:.4}to{opacity:1}}}
@media print{body{background:white;color:black}header nav,footer,details{display:none}:root{--ink:#111;--dim:#444;--panel:#fff;--line:#aaa;--teal:#164d42;--accent:#695013}.wrap{max-width:none}.layout{grid-template-columns:1fr 1.5fr}.piece,.exercise{break-inside:avoid}}
.scale-list{display:flex;flex-wrap:wrap;gap:4px 18px;margin-top:8px;padding-left:0;list-style:none}.scale-list li{margin:0}.scale-list li+li{margin-top:0}.scale{margin:0;border-top:0;padding-top:0}.scale[open]{flex-basis:100%}.scale summary{display:inline-flex;align-items:center;gap:6px;min-height:24px;color:var(--ink);font-weight:600;list-style:none}.scale summary::-webkit-details-marker{display:none}.scale summary::after{content:'+';color:var(--accent);font-size:.9rem;font-weight:700}.scale[open] summary::after{content:'-'}.scale-content{padding:1px 0 6px;color:var(--dim);font-size:.95rem}.scale-content p{margin:1px 0}.scale-content strong{color:var(--dim);font-size:.9rem}