.tool-header{padding:clamp(3rem,6vw,5rem) clamp(1rem,4vw,3rem) 2rem;border-bottom:1px solid var(--line)}.tool-header-inner{max-width:900px;margin:0 auto}.breadcrumb{display:flex;align-items:center;gap:.5rem;font-size:.8rem;color:var(--text-2);margin-bottom:1.25rem}.breadcrumb a{color:var(--text)}.breadcrumb a:hover{text-decoration:underline}.tool-title{font-family:var(--font-display);font-size:var(--step-h1);line-height:1.1;letter-spacing:-.02em;margin-bottom:.75rem}.tool-title em{color:inherit}.tool-desc{color:var(--text-2);font-size:var(--step-lead);max-width:560px}.piano-section{padding:2.5rem clamp(1rem,4vw,3rem) 3rem}.piano-wrap{max-width:960px;margin:0 auto;background:var(--surface);border:1px solid var(--line);border-radius:var(--radius);overflow:hidden}.controls-bar{display:flex;align-items:center;gap:1.5rem;padding:1rem 1.5rem;border-bottom:1px solid var(--line);flex-wrap:wrap}.control-group{display:flex;align-items:center;gap:.6rem}.control-label{font-size:.8rem;color:var(--text-2);text-transform:none;letter-spacing:0;white-space:nowrap}.volume-wrap{display:flex;align-items:center;gap:.4rem;color:var(--text-2)}.volume-slider{-webkit-appearance:none;appearance:none;width:100px;height:4px;background:var(--line);border-radius:2px;outline:none;cursor:pointer;position:relative}.volume-slider::-webkit-slider-thumb{-webkit-appearance:none;appearance:none;width:14px;height:14px;border-radius:50%;background:var(--accent);cursor:pointer;transition:transform .15s}.volume-slider::-webkit-slider-thumb:hover{transform:scale(1.2)}.volume-slider::-moz-range-thumb{width:14px;height:14px;border-radius:50%;background:var(--accent);border:none;cursor:pointer}.octave-wrap{display:flex;align-items:center;gap:.25rem;background:var(--surface);border:1px solid var(--line);border-radius:8px;padding:2px 4px}.octave-btn{background:none;border:none;color:var(--text-2);cursor:pointer;padding:4px 6px;border-radius:5px;display:flex;align-items:center;transition:background .15s,color .15s}.octave-btn:hover{background:var(--line);color:var(--text)}.octave-btn:disabled{opacity:.3;cursor:not-allowed}.octave-display{font-size:.8rem;font-weight:600;letter-spacing:.02em;padding:0 6px;white-space:nowrap}.sustain-btn{display:flex;align-items:center;gap:.4rem;background:var(--surface);border:1px solid var(--line);border-radius:8px;color:var(--text-2);font-size:.8rem;font-weight:600;padding:6px 12px;cursor:pointer;transition:all .18s}.sustain-btn[aria-pressed=true]{background:rgba(var(--accent-rgb),.12);border-color:rgba(var(--accent-rgb),.4);color:var(--accent)}.sustain-dot{width:7px;height:7px;border-radius:50%;background:currentColor;transition:background .18s}.hint-toggle{background:var(--surface);border:1px solid var(--line);border-radius:8px;color:var(--text-2);font-size:.8rem;font-weight:600;padding:6px 12px;cursor:pointer;transition:all .18s}.hint-toggle:hover{border-color:var(--text-2);color:var(--text)}.hint-toggle.active{background:rgba(var(--accent-rgb),.08);border-color:rgba(var(--accent-rgb),.3);color:var(--accent)}.piano-outer{overflow-x:auto;padding:2rem 1.5rem 1.5rem;-webkit-overflow-scrolling:touch;scrollbar-width:thin;scrollbar-color:var(--line) transparent}.piano-outer::-webkit-scrollbar{height:4px}.piano-outer::-webkit-scrollbar-track{background:transparent}.piano-outer::-webkit-scrollbar-thumb{background:var(--line);border-radius:2px}.piano-keyboard{position:relative;display:flex;align-items:flex-start;height:260px;min-width:700px;width:fit-content;margin:0 auto;user-select:none;-webkit-user-select:none}.key-white{position:relative;width:50px;height:260px;background:linear-gradient(180deg,rgba(var(--text-rgb),.88) 0%,var(--text) 42%,rgba(var(--text-rgb),.93) 100%);border:1px solid var(--line);border-radius:0 0 6px 6px;cursor:pointer;flex-shrink:0;display:flex;flex-direction:column;align-items:center;justify-content:flex-end;padding-bottom:10px;gap:2px;transition:background .08s,transform .08s;-webkit-tap-highlight-color:transparent;touch-action:none;box-shadow:inset 0 -4px 8px #00000026,2px 0 #00000014;z-index:1}.key-white:hover{background:linear-gradient(180deg,rgba(var(--text-rgb),.76),rgba(var(--text-rgb),.9) 42%,rgba(var(--text-rgb),.82))}.key-white.pressed,.key-white.key-active{background:linear-gradient(180deg,var(--accent) 0%,var(--accent-dim) 100%);transform:scaleY(.98);transform-origin:top center;box-shadow:inset 0 -2px 4px #0003,0 0 16px rgba(var(--accent-rgb),.4),2px 0 #00000014}.key-note{font-size:.62rem;font-weight:700;color:var(--accent-ink);letter-spacing:.02em;line-height:1;transition:opacity .15s}.key-white.key-active .key-note{color:var(--accent-ink)}.key-shortcut{font-size:.55rem;color:var(--accent-ink);letter-spacing:.02em;line-height:1;background:#0000000f;padding:1px 3px;border-radius:3px;transition:opacity .15s}.key-white.key-active .key-shortcut{color:var(--accent-ink)}.hints-hidden .key-shortcut{opacity:0}.key-black{position:absolute;width:32px;height:160px;background:linear-gradient(180deg,var(--surface-2) 0%,var(--surface) 55%,var(--bg) 100%);border-radius:0 0 5px 5px;cursor:pointer;z-index:2;display:flex;flex-direction:column;align-items:center;justify-content:flex-end;padding-bottom:8px;gap:2px;transition:background .08s,transform .08s;-webkit-tap-highlight-color:transparent;touch-action:none;box-shadow:2px 4px 8px #00000080,inset 0 1px rgba(var(--text-rgb),.08)}.key-black:hover{background:linear-gradient(180deg,var(--surface-2) 0%,var(--surface-2) 55%,var(--surface) 100%)}.key-black.pressed,.key-black.key-active{background:linear-gradient(180deg,var(--accent) 0%,var(--accent-dim) 100%);transform:scaleY(.97);transform-origin:top center;box-shadow:1px 2px 4px #0006,0 0 12px rgba(var(--accent-rgb),.5),inset 0 1px rgba(var(--text-rgb),.15)}.key-black .key-note{font-size:.55rem;color:var(--text-2);letter-spacing:0em}.key-black.key-active .key-note{color:var(--accent-ink)}.key-black .key-shortcut{font-size:.5rem;color:var(--text-2);background:rgba(var(--text-rgb),.06)}.key-black.key-active .key-shortcut{color:var(--accent-ink)}.note-display{display:flex;align-items:baseline;gap:.75rem;padding:.75rem 1.5rem 1.25rem;border-top:1px solid var(--line);min-height:52px}.note-name{font-family:var(--font-display);font-size:1.5rem;color:var(--accent);min-width:40px;line-height:1}.note-freq{font-size:.85rem;color:var(--text-2)}.seo-section{padding:0 clamp(1rem,4vw,3rem) 4rem}.seo-inner{max-width:900px;margin:0 auto;display:flex;flex-direction:column;gap:3.5rem}.seo-block h2{font-family:var(--font-display);font-size:clamp(1.4rem,3vw,1.9rem);letter-spacing:-.02em;margin-bottom:1rem}.seo-block p{color:var(--text-2);line-height:1.75;margin-bottom:.75rem}.seo-block ul,.seo-block ol{color:var(--text-2);padding-left:1.25rem;display:flex;flex-direction:column;gap:.6rem;line-height:1.7}.seo-block li strong,.seo-block a{color:var(--text)}.seo-block a:hover{text-decoration:underline}.freq-table-wrap{overflow-x:auto;border:1px solid var(--line);border-radius:var(--radius);margin-top:1rem}.freq-table{width:100%;border-collapse:collapse;font-size:.88rem}.freq-table th{text-align:left;padding:.75rem 1rem;background:var(--surface);color:var(--text-2);font-size:.8rem;text-transform:none;letter-spacing:0;border-bottom:1px solid var(--line);font-weight:600}.freq-table td{padding:.65rem 1rem;border-bottom:1px solid var(--line);color:var(--text)}.freq-table tr:last-child td{border-bottom:none}.freq-table tr:nth-child(2n) td{background:rgba(var(--text-rgb),.02)}.seo-tools-cta{display:grid;grid-template-columns:minmax(0,1fr) 1fr;gap:2rem;align-items:start}.other-tools h3{font-size:1rem;font-weight:700;margin-bottom:1rem;letter-spacing:-.01em}.tools-grid{display:flex;flex-direction:column;gap:.6rem}.tool-card{display:flex;align-items:center;gap:.85rem;padding:.85rem 1rem;background:var(--surface);border:1px solid var(--line);border-radius:10px;transition:border-color .18s,background .18s}.tool-card:hover{border-color:var(--line);background:var(--surface)}.tool-card-icon{width:36px;height:36px;background:var(--surface);border:1px solid var(--line);border-radius:8px;display:flex;align-items:center;justify-content:center;color:var(--text-2);flex-shrink:0}.tool-card:hover .tool-card-icon{color:var(--text);border-color:rgba(var(--text-rgb),.3)}.tool-card-name{font-size:.88rem;font-weight:600;margin-bottom:.15rem}.tool-card-desc{font-size:.78rem;color:var(--text-2)}.cta-card{background:var(--surface);border:1px solid var(--line);border-radius:var(--radius);padding:2rem;position:relative;overflow:hidden}.cta-card:before{content:"";position:absolute;top:0;left:0;right:0;height:2px;background:var(--action)}.cta-card-tag{font-size:.8rem;text-transform:none;letter-spacing:0;color:var(--text-2);font-weight:700;margin-bottom:.75rem}.cta-card h3{font-family:var(--font-display);font-size:1.5rem;letter-spacing:-.02em;margin-bottom:.75rem}.cta-card p{color:var(--text-2);font-size:.88rem;line-height:1.65;margin-bottom:1.5rem}.cta-card-btn{display:inline-block;background:var(--action);color:var(--action-ink);font-weight:700;font-size:.88rem;padding:10px 22px;border-radius:8px;transition:background .15s,transform .15s}.cta-card-btn:hover{background:var(--action-dim);transform:translateY(-1px)}@media(max-width:700px){.controls-bar{gap:1rem}.keyboard-hint-control{display:none}.piano-keyboard{height:200px}.key-white{width:40px;height:200px;padding-bottom:8px}.key-black{width:26px;height:120px;padding-bottom:6px}.key-note{font-size:.55rem}.key-shortcut{display:none}.seo-tools-cta{grid-template-columns:minmax(0,1fr)}.volume-slider{width:70px}}@media(max-width:480px){.piano-keyboard{min-width:480px;height:180px}.key-white{width:36px;height:180px}.key-black{width:24px;height:108px}}