:root{--bg:#f7f6f2;--card:#fff;--ink:#1d1f23;--soft:#585d66;--line:#dcdad3;--acc:#b8430f;--acc-l:#fbe9df;--ok:#1d7a3e;--ok-l:#e2f3e7}
*{box-sizing:border-box}
html{-webkit-text-size-adjust:100%}
body{margin:0;background:var(--bg);color:var(--ink);font:18px/1.6 system-ui,-apple-system,"Segoe UI",Roboto,Helvetica,Arial,sans-serif}
a{color:var(--acc)}
.wrap{max-width:1080px;margin:0 auto;padding:0 16px}
.skip{position:absolute;left:-999px}.skip:focus{left:8px;top:8px;background:#fff;padding:8px;z-index:9}
.sr{position:absolute;width:1px;height:1px;overflow:hidden;clip:rect(0 0 0 0);white-space:nowrap}
.top{background:var(--card);border-bottom:1px solid var(--line)}
.top .wrap{display:flex;align-items:center;justify-content:space-between;min-height:54px;gap:12px;flex-wrap:wrap}
.brand{font-weight:700;font-size:19px;color:var(--ink);text-decoration:none;display:flex;align-items:center;gap:8px;padding:8px 0}
.brand span{color:var(--acc)}
.top nav{display:flex;gap:4px 16px;flex-wrap:wrap;font-size:16px}
.top nav a{text-decoration:none;color:var(--ink);padding:10px 0;display:inline-block}
.top nav a[aria-current]{color:var(--acc);font-weight:600}
@media (max-width:640px){.top .wrap{flex-direction:column;align-items:flex-start;gap:0}.top nav{gap:0 14px;font-size:15px}.top nav a{padding:6px 0 10px}}
.crumbs{font-size:15px;color:var(--soft);margin:12px 0 0}.crumbs a{color:var(--soft)}
h1{font-size:30px;line-height:1.2;margin:16px 0 6px}
h2{font-size:24px;line-height:1.25;margin:34px 0 8px}
h3{font-size:19px;margin:22px 0 4px}
.lead{font-size:18px;color:var(--soft);margin:0 0 16px;max-width:68ch}
.card{background:var(--card);border:1px solid var(--line);border-radius:14px;padding:16px;margin:0 0 18px}
.card-h{font-size:20px;margin:0 0 10px}
.btn{font:inherit;font-size:18px;font-weight:600;min-height:48px;padding:8px 20px;border-radius:10px;border:2px solid var(--acc);background:var(--acc);color:#fff;cursor:pointer}
.btn-sec{font:inherit;font-size:16px;min-height:44px;padding:6px 14px;border-radius:10px;border:1px solid var(--acc);background:#fff;color:var(--acc);cursor:pointer}
.btn:disabled{opacity:.55;cursor:default}
.btn-row{display:flex;gap:10px;flex-wrap:wrap;align-items:center;margin:8px 0}
select,input[type=range]{font:inherit;font-size:17px;accent-color:var(--acc)}
select{min-height:44px;padding:6px 10px;border:1px solid var(--line);border-radius:9px;background:#fff;color:var(--ink);max-width:100%}
.field{display:flex;flex-wrap:wrap;gap:6px 12px;align-items:center;margin:0 0 10px}
.lab{font-size:16px;color:var(--soft);margin:10px 0 4px}
.why{background:var(--acc-l);border-radius:10px;padding:10px 14px;font-size:16px;margin:0 0 10px}
.why b{display:block}
.why p{margin:4px 0 0}
.t-display{display:grid;grid-template-columns:minmax(0,1fr);gap:4px;justify-items:center;text-align:center;margin:8px 0}
@media (min-width:760px){.t-display{grid-template-columns:minmax(0,1.2fr) minmax(0,1fr);align-items:center}}
.gauge{width:100%;max-width:340px;aspect-ratio:300/175;display:block}
.gauge .arc{fill:none;stroke:var(--line);stroke-width:10;stroke-linecap:round}
.gauge .zone{fill:none;stroke:var(--ok);stroke-width:14}
.gauge .tick{stroke:#9a9ea6;stroke-width:2}
.gauge .lbl{font-size:13px;fill:var(--soft)}
.gauge .needle line{stroke:var(--ink);stroke-width:4;stroke-linecap:round}
.gauge .hub{fill:var(--ink)}
[data-state=ok] .gauge .needle line,[data-state=ok] .gauge .hub{stroke:var(--ok);fill:var(--ok)}
.t-notebox{margin:0;font-size:64px;font-weight:700;line-height:1;min-height:64px}
.t-oct{font-size:22px;color:var(--soft);font-weight:500}
[data-state=ok] .t-note{color:var(--ok)}
.t-cents{margin:4px 0 0;font-size:22px;font-weight:600;min-height:1.5em}
.t-hz{margin:0;font-size:15px;color:var(--soft);min-height:3.2em}
.t-msg{text-align:center;font-size:19px;font-weight:600;min-height:3.2em;margin:4px 0;padding:6px;border-radius:9px}
[data-state=ok]~.t-msg{background:var(--ok-l);color:var(--ok)}
.t-strings,.r-strings,.chbtns{display:flex;flex-wrap:wrap;gap:8px}
.sbtn,.chbtn{font:inherit;font-size:16px;min-height:44px;min-width:58px;padding:6px 10px;border-radius:9px;border:1px solid var(--line);background:#fff;color:var(--ink);cursor:pointer}
.sbtn[aria-pressed=true],.chbtn[aria-pressed=true]{border-color:var(--acc);background:var(--acc);color:#fff}
.sbtn.hit{box-shadow:0 0 0 3px var(--acc) inset}
.rbtn{font:inherit;display:flex;flex-direction:column;align-items:center;min-width:92px;min-height:64px;padding:6px 10px;border-radius:10px;border:1px solid var(--line);background:#fff;color:var(--ink);cursor:pointer}
.rbtn b{font-size:22px}.rbtn span{font-size:13px;color:var(--soft)}
.rbtn.on{background:var(--acc);border-color:var(--acc);color:#fff}.rbtn.on span{color:#fff}
.chk{display:flex;gap:8px;align-items:center;font-size:16px}
.two{display:flex;flex-wrap:wrap;gap:10px 24px;align-items:center;margin-top:10px}
.privacy-note{font-size:15px;color:var(--soft);margin:10px 0 0}
.t-err{border:2px solid var(--acc);border-radius:10px;padding:10px 14px;margin:12px 0 0;font-size:16px;background:#fff}
.t-err details{margin:6px 0}.t-err summary{cursor:pointer;font-weight:600;min-height:32px}
details summary{cursor:pointer}
.answer{background:var(--card);border-left:4px solid var(--acc);padding:10px 14px;border-radius:6px;max-width:72ch;font-size:17px;margin:0 0 16px}
.prose{max-width:72ch}
.table-wrap{overflow-x:auto}
table{border-collapse:collapse;font-size:16px;background:#fff;min-width:100%}
th,td{border:1px solid var(--line);padding:6px 8px;text-align:left;vertical-align:top}
caption{text-align:left;font-weight:600;padding:6px 0}
.faq details{background:#fff;border:1px solid var(--line);border-radius:10px;padding:10px 14px;margin:8px 0;max-width:72ch}
.faq summary{font-weight:600}
.rel{display:grid;grid-template-columns:repeat(auto-fill,minmax(220px,1fr));gap:10px;padding:0;list-style:none}
.rel a{display:block;background:#fff;border:1px solid var(--line);border-radius:10px;padding:10px 14px;text-decoration:none;min-height:44px}
.rel small{display:block;color:var(--soft)}
.updated{font-size:15px;color:var(--soft)}
/* virtual guitar */
.fb-scroll{overflow-x:auto;-webkit-overflow-scrolling:touch;border-radius:10px;background:#5b3a22;padding:8px 6px}
.fb{min-width:760px;display:flex;flex-direction:column;gap:3px;touch-action:manipulation;user-select:none;-webkit-user-select:none}
.fr{display:grid;grid-template-columns:52px repeat(12,minmax(0,1fr));gap:3px}
.fc{font:inherit;font-size:14px;min-height:40px;border:0;border-radius:5px;background:#e9dccb;color:#3a2a1c;cursor:pointer;padding:0}
.fc.open{background:#fff8ef;font-weight:700}
.fc.ch{background:var(--acc);color:#fff;font-weight:700}
.fc.mute{background:#c9bfb3;color:#7a6e62;text-decoration:line-through}
.fc.hit{outline:3px solid #ffd27a;outline-offset:-3px}
.fnums{display:grid;grid-template-columns:52px repeat(12,minmax(0,1fr));gap:3px;font-size:12px;color:#f3e6d6;text-align:center;min-width:760px}
.g-now{min-height:1.6em;font-weight:600;margin:8px 0 0}
.chords{display:grid;grid-template-columns:repeat(auto-fill,minmax(130px,1fr));gap:10px;list-style:none;padding:0}
.chords li{background:#fff;border:1px solid var(--line);border-radius:10px;padding:8px;text-align:center}
.chords svg{width:110px;height:auto;display:block;margin:0 auto}
.chords small{color:var(--soft);font-size:14px}
footer{margin-top:40px;background:var(--card);border-top:1px solid var(--line);font-size:15px;color:var(--soft);padding:18px 0 28px}
footer ul{list-style:none;padding:0;display:flex;flex-wrap:wrap;gap:4px 16px;margin:0 0 10px}
footer a{display:inline-block;padding:6px 0}
@media (max-width:420px){h1{font-size:26px}.t-notebox{font-size:56px}}
@media (prefers-reduced-motion:no-preference){.gauge .needle{transition:transform .12s linear}}
@media print{.top,footer,.tool{display:none}}