:root{color:#1f2933;background:#f5f7f9;font-family:Inter,ui-sans-serif,system-ui,-apple-system,BlinkMacSystemFont,Segoe UI,Noto Sans TC,sans-serif;font-synthesis:none;text-rendering:optimizeLegibility;-webkit-font-smoothing:antialiased;--ink: #1f2933;--muted: #697586;--line: #d9e2ec;--panel: #ffffff;--surface: #eef3f7;--root: #ef6f61;--third: #3b82c4;--fifth: #1f9d8a;--seventh: #8a6fcb;--scale: #7b8794;--shadow-sm: 0 1px 2px rgba(31, 41, 51, .05);--shadow-md: 0 12px 34px rgba(31, 41, 51, .08)}*{box-sizing:border-box}body{margin:0;min-width:1120px;background:linear-gradient(180deg,#f8fafc,#eef3f7)}button,select,input{font:inherit}button,select{cursor:pointer}.app-shell{min-height:100vh;padding:22px clamp(20px,2vw,34px) 34px}.hero{display:flex;justify-content:space-between;gap:24px;align-items:center;margin:0 auto 14px;max-width:1680px;padding:0 2px}.hero h1{margin:3px 0 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p{margin:0;color:var(--muted);font-size:13px;line-height:1.65}@media(min-width:1520px){.app-shell{padding-top:24px}.workspace{grid-template-columns:minmax(1120px,1fr) 380px}.fret-cell{min-height:68px}}@media(max-width:1320px){.control-bar{grid-template-columns:110px minmax(230px,1fr) minmax(380px,1.25fr)}.control-group:last-child{grid-column:1 / -1}.workspace{grid-template-columns:minmax(880px,1fr) 340px}}@media(max-width:1180px){body{min-width:0}.app-shell{padding:20px}.hero,.workspace{display:grid;grid-template-columns:1fr}.control-bar{grid-template-columns:1fr;position:static}.fretboard-card{overflow-x:auto}.side-panel{grid-template-columns:repeat(2,minmax(0,1fr));position:static;max-height:none;overflow:visible}.practice-panel{grid-column:1 / -1}}