:root{--bg:#0b0b0d;--panel:#16161a;--line:#2a2a31;--text:#f3f3f5;--muted:#a3a3ad;--accent:#ff2a4a;--accent-2:#c8102e;--ok:#35d07f;--r:14px}
*{box-sizing:border-box}
html{-webkit-text-size-adjust:100%}
body{margin:0;background:var(--bg);color:var(--text);font:16px/1.5 system-ui,-apple-system,"Segoe UI",Roboto,sans-serif;padding-bottom:env(safe-area-inset-bottom)}
a{color:inherit}
.skip{position:absolute;left:-999px;top:0;background:#fff;color:#000;padding:.6rem 1rem;z-index:10}
.skip:focus{left:8px;top:8px}
.top{display:flex;flex-wrap:wrap;align-items:center;gap:.5rem 1rem;padding:.75rem 1rem;padding-top:calc(.75rem + env(safe-area-inset-top));border-bottom:1px solid var(--line);position:sticky;top:0;background:rgba(11,11,13,.92);backdrop-filter:blur(8px);z-index:5}
.brand{font-weight:800;text-decoration:none;letter-spacing:.3px;margin-right:auto}
.nav,.langs{display:flex;gap:.25rem}
.nav a,.langs a{min-height:44px;min-width:44px;display:inline-flex;align-items:center;justify-content:center;padding:0 .75rem;border-radius:10px;text-decoration:none;color:var(--muted)}
.nav a[aria-current],.langs a[aria-current]{color:var(--text);background:var(--panel)}
.langs a{font-weight:700;font-size:.85rem;border:1px solid var(--line)}
main{max-width:720px;margin:0 auto;padding:1.25rem 1rem 3rem}
h1{font-size:clamp(1.7rem,6vw,2.4rem);line-height:1.15;margin:.5rem 0}
h2{font-size:1.2rem;margin:2rem 0 .75rem}
.lead{color:var(--muted);font-size:1.05rem}
.hero{padding:1.5rem 0 .5rem}
.btn{display:inline-flex;align-items:center;justify-content:center;min-height:48px;padding:0 1.4rem;border-radius:var(--r);border:1px solid var(--line);background:var(--panel);color:var(--text);font:inherit;font-weight:700;cursor:pointer;text-decoration:none;touch-action:manipulation}
.btn:focus-visible,.step:focus-visible,select:focus-visible,input:focus-visible,a:focus-visible{outline:3px solid #fff;outline-offset:2px}
.btn-primary{background:var(--accent);border-color:var(--accent);color:#fff}
.btn-primary:active{background:var(--accent-2)}
.btn-big{min-height:64px;font-size:1.25rem;flex:2}
.btn-tap{min-height:64px;flex:1;font-size:1.05rem;user-select:none;-webkit-user-select:none}
.btn-tap:active{background:#24242b}
.is-on{background:#333;border-color:#555}
.cards{list-style:none;padding:0;margin:0;display:grid;gap:.75rem}
.card{background:var(--panel);border:1px solid var(--line);border-radius:var(--r);padding:1rem 1.1rem}
.card h3{margin:0 0 .25rem;font-size:1.1rem}
.card p{margin:0;color:var(--muted)}
.card-soon{opacity:.7}
.badge{font-size:.7rem;font-weight:700;background:#2a2a31;color:var(--muted);padding:.15rem .5rem;border-radius:99px;vertical-align:middle}
.display{display:flex;align-items:center;justify-content:space-between;gap:.75rem;margin:1.25rem 0 .5rem}
.bpm-box{text-align:center;flex:1}
.bpm{display:block;font-size:clamp(4.5rem,24vw,7.5rem);font-weight:800;line-height:1;font-variant-numeric:tabular-nums}
.bpm-label{display:block;color:var(--muted);letter-spacing:3px;font-weight:700}
.tempo-name{display:block;color:var(--accent);font-style:italic;min-height:1.5em}
.step{width:64px;height:64px;border-radius:50%;border:1px solid var(--line);background:var(--panel);color:var(--text);font-size:2rem;cursor:pointer;touch-action:manipulation;flex:none}
.step:active{background:#24242b}
input[type=range]{accent-color:var(--accent)}
.range{width:100%;height:44px;accent-color:var(--accent);margin:.25rem 0 1rem;touch-action:manipulation}
.beats{display:flex;justify-content:center;flex-wrap:wrap;gap:.6rem;margin:.5rem 0 1.25rem;min-height:32px}
.dot{width:28px;height:28px;border-radius:50%;background:#26262d;border:2px solid #3a3a43;transition:background .05s}
.dot-first{border-color:var(--accent)}
.dot.on{background:var(--ok);border-color:var(--ok)}
.dot-first.on{background:var(--accent);border-color:var(--accent)}
.actions{display:flex;gap:.75rem}
.hint{color:var(--muted);font-size:.9rem;text-align:center;margin:.5rem 0}
.opts{display:grid;grid-template-columns:1fr 1fr;gap:.75rem;margin-top:1.25rem}
.field{display:flex;flex-direction:column;gap:.25rem;font-size:.9rem;color:var(--muted)}
.field-range{grid-column:1/-1}
select{min-height:48px;border-radius:12px;background:var(--panel);color:var(--text);border:1px solid var(--line);padding:0 .75rem;font:inherit}
.check{grid-column:1/-1;display:flex;align-items:center;gap:.6rem;min-height:44px;color:var(--text)}
.check input{width:24px;height:24px;accent-color:var(--accent)}
.how ol{padding-left:1.25rem}
.tip{background:var(--panel);border-left:4px solid var(--accent);padding:.75rem 1rem;border-radius:8px}
.foot{border-top:1px solid var(--line);padding:1.25rem 1rem;text-align:center;color:var(--muted);font-size:.85rem}
.foot p{margin:.2rem 0}
@media (min-width:640px){.cards{grid-template-columns:repeat(3,1fr)}.opts{grid-template-columns:repeat(3,1fr)}.field-range{grid-column:auto}.keys{display:block}}
@media (max-width:639px){.keys{display:none}}
@media (prefers-reduced-motion:reduce){*{transition:none!important}}

/* Ferramentas: afinador, escalas, acordes */
.nav{flex-wrap:wrap}
.opts-2{grid-template-columns:1fr 1fr}
.num{min-height:48px;border-radius:12px;background:var(--panel);color:var(--text);border:1px solid var(--line);padding:0 .75rem;font:inherit;width:100%}
.h2-small{font-size:1rem;color:var(--muted);margin:1.5rem 0 .6rem}
.gauge{margin:1.25rem 0;padding:1rem;background:var(--panel);border:1px solid var(--line);border-radius:var(--r);text-align:center;border-left:6px solid var(--line)}
.gauge.ok{border-left-color:var(--ok)} .gauge.flat{border-left-color:#4aa3ff} .gauge.sharp{border-left-color:#ffb020}
.needle-wrap{position:relative;height:84px;margin:0 auto;max-width:280px}
.needle{position:absolute;left:50%;bottom:0;width:4px;height:78px;margin-left:-2px;background:var(--accent);border-radius:3px;transform-origin:50% 100%;transition:transform .12s linear}
.gauge.ok .needle{background:var(--ok)}
.ticks{position:absolute;inset:auto 0 0 0;height:2px;background:linear-gradient(90deg,transparent,#444 15%,#444 85%,transparent)}
.tn-note{font-size:clamp(3.5rem,18vw,5.5rem);font-weight:800;line-height:1.1;min-height:1.1em}
.tn-cents{color:var(--muted);min-height:1.5em;font-variant-numeric:tabular-nums}
.tn-status{margin:.5rem 0 0;min-height:1.5em;color:var(--muted)}
.gauge.ok .tn-status{color:var(--ok);font-weight:700}
.strs{display:flex;flex-wrap:wrap;gap:.5rem}
.str{min-width:56px;min-height:56px;border-radius:12px;border:1px solid var(--line);background:var(--panel);color:var(--text);font:inherit;font-weight:700;cursor:pointer;touch-action:manipulation}
.str.on{background:var(--accent);border-color:var(--accent)}
.fb-wrap{overflow-x:auto;margin:1rem -1rem 0;padding:0 1rem;-webkit-overflow-scrolling:touch}
.fb{display:block;max-width:none}
.fb-fret{stroke:#4a4a55;stroke-width:1.5} .fb-nut{stroke:#d8d8df;stroke-width:5} .fb-string{stroke:#9a9aa5}
.fb-mark{fill:#2a2a31} .fb-num{fill:var(--muted);font-size:11px}
.fb-dot{fill:#3b82f6} .fb-root{fill:var(--accent)} .fb-lbl{fill:#fff;font-size:11px;font-weight:700;pointer-events:none}
.facts{display:grid;gap:.25rem;margin:1rem 0}
.facts dt{color:var(--muted);font-size:.9rem;margin-top:.5rem} .facts dd{margin:0;font-size:1.1rem;letter-spacing:.5px}
.chord-name{font-size:2.2rem;margin:1.25rem 0 .25rem}
.facts-line{color:var(--muted);margin:.25rem 0}
.cd-list{list-style:none;padding:0;margin:0;display:grid;grid-template-columns:repeat(auto-fill,minmax(150px,1fr));gap:.75rem}
.cd-card{background:var(--panel);border:1px solid var(--line);border-radius:var(--r);padding:.75rem;display:flex;flex-direction:column;align-items:center;gap:.5rem}
.cd{height:auto;max-width:100%}
.cd-fret{stroke:#555;stroke-width:1} .cd-nut{stroke:#ddd;stroke-width:4} .cd-string{stroke:#888;stroke-width:1}
.cd-dot{fill:var(--accent)} .cd-open{fill:none;stroke:#ddd;stroke-width:1.5} .cd-mark{fill:#ddd;font-size:14px;font-weight:700} .cd-base{fill:var(--muted);font-size:12px}
.cd-cap{color:var(--muted);font-size:.8rem;letter-spacing:2px}
.btn-small{min-height:44px;padding:0 1rem;font-size:.9rem}
@media (min-width:640px){.opts{grid-template-columns:repeat(3,1fr)}.fb-wrap{margin:1rem 0;padding:0}}
/* corrige grade que estourava a largura em telas estreitas */
.opts>*,.opts-2>*{min-width:0}
.field select,.field .num{width:100%;max-width:100%;min-width:0}
.nav{gap:.1rem}
.nav a{padding:0 .6rem}
html,body{overflow-x:hidden}

/* Curso Básico (rascunho) */
.course{max-width:720px}
.cr-draft{background:#3a2a05;border:1px solid #b88a1a;color:#ffd77a;padding:.6rem .9rem;border-radius:10px;font-size:.9rem}
.cr-head{margin:1.25rem 0 1rem}.cr-sub{color:var(--accent);font-weight:700;margin:.25rem 0}
.cr-toc{background:var(--panel);border:1px solid var(--line);border-radius:var(--r);padding:.5rem 1rem 1rem;margin:1rem 0}
.cr-toc h2{font-size:1rem;margin:.75rem 0 .4rem}.cr-toc ol{margin:0;padding-left:1.25rem}
.cr-toc a{display:inline-block;min-height:44px;line-height:44px}
.cr-lesson{border-top:1px solid var(--line);margin-top:2.5rem;padding-top:1.5rem;scroll-margin-top:90px}
.cr-num{color:var(--accent);font-weight:800;letter-spacing:1px;margin:0;text-transform:uppercase;font-size:.8rem}
.cr-lesson h2{margin:.25rem 0 .5rem;font-size:1.6rem}
.cr-lesson h3{font-size:1.1rem;margin:1.5rem 0 .4rem}
.cr-goal{background:var(--panel);border-left:4px solid var(--accent);padding:.6rem .9rem;border-radius:8px}
.course p,.course li{line-height:1.65}.course li{margin:.3rem 0}
.cr-note-box{background:#13202b;border-left:4px solid #4aa3ff;padding:.6rem .9rem;border-radius:8px}
.cr-formula{font-family:ui-monospace,Consolas,monospace;font-size:1.05rem;background:var(--panel);border:1px dashed #555;padding:.7rem .9rem;border-radius:8px;overflow-x:auto;white-space:nowrap}
.cr-tab{background:#0f0f12;border:1px solid var(--line);border-radius:8px;padding:.75rem;overflow-x:auto;font-size:.85rem;line-height:1.35}
.cr-tablewrap{overflow-x:auto;margin:.75rem 0;-webkit-overflow-scrolling:touch}
.cr-table{border-collapse:collapse;min-width:100%;font-size:.95rem}
.cr-table th,.cr-table td{border:1px solid var(--line);padding:.5rem .65rem;text-align:left;vertical-align:top}
.cr-table thead th{background:var(--panel)}.cr-table tbody th{background:#121216;font-weight:600}
.cr-ex{background:var(--panel);border:1px solid var(--line);border-radius:var(--r);padding:.25rem 1rem 1rem;margin:1.25rem 0}
.cr-ex h4{margin:.75rem 0 .25rem;color:var(--accent)}
.cr-ans{margin:.75rem 0;border:1px solid var(--line);border-radius:10px;padding:0 .9rem}
.cr-ans summary{min-height:44px;display:flex;align-items:center;cursor:pointer;font-weight:700}
.cr-check{margin-top:1.5rem;background:var(--panel);border-radius:var(--r);padding:.5rem 1rem 1rem}
.cr-check h3{font-size:1rem;margin:.75rem 0}.cr-check ul{list-style:none;padding:0}
.cr-check label{display:flex;gap:.6rem;align-items:flex-start;min-height:44px;padding:.2rem 0}
.cr-check input{width:24px;height:24px;accent-color:var(--accent);flex:none;margin-top:.15rem}
.cr-fig{margin:1rem 0;text-align:center}.cr-svg{width:100%;max-width:380px;height:auto}
.cr-ring{fill:none;stroke:#333;stroke-width:2}
.cr-note{fill:#1c1c22;stroke:#666;stroke-width:2}.cr-acc{fill:#2a1118;stroke:var(--accent);stroke-width:2}
.cr-nt{fill:#fff;font-weight:800;font-size:17px}.cr-nt2{fill:#fff;font-weight:700;font-size:13px}
.cr-t{fill:#1f3a2a;stroke:var(--ok)}.cr-s{fill:#3a1f24;stroke:var(--accent)}.cr-mk{fill:#fff;font-weight:800;font-size:13px}
.cr-cap{fill:var(--muted);font-size:12px}
.cr-tool{margin:.25rem 0}
@media print{.top,.foot,.cr-draft,.cr-tool{display:none}body{background:#fff;color:#000}.cr-ans[open] summary{display:none}}
/* Bases (backing tracks) */
.bk-chart{display:grid;grid-template-columns:repeat(4,1fr);gap:.5rem;margin:1rem 0 .5rem}
.bk-bar{display:flex;align-items:center;justify-content:center;min-height:56px;border-radius:10px;background:#26262d;border:2px solid #3a3a43;font-weight:700;font-size:1.1rem;transition:background .08s}
.bk-bar.on{background:var(--accent);border-color:var(--accent);color:#fff}
.bk-hint{min-height:2.6em}
@media (max-width:420px){.bk-bar{min-height:48px;font-size:1rem}}