:root{color:#172126;background:#edf1f0;font-family:Inter,ui-sans-serif,system-ui,-apple-system,BlinkMacSystemFont,Segoe UI,sans-serif;font-synthesis:none;text-rendering:optimizeLegibility;-webkit-font-smoothing:antialiased;--ink: #172126;--muted: #5d6b70;--surface: #ffffff;--surface-soft: #f5f7f6;--line: #ccd5d3;--teal: #0f766e;--teal-dark: #115e59;--coral: #bd452f;--amber: #eeb241;--shadow: 0 16px 42px rgba(23, 33, 38, .1)}*{box-sizing:border-box}body{margin:0;min-width:320px;min-height:100vh}button,textarea,input,select{font:inherit}button,a{-webkit-tap-highlight-color:transparent}button{cursor:pointer}button:disabled{cursor:not-allowed;opacity:.52}.app-shell{min-height:100vh;padding:0 20px 48px;background:#edf1f0}.app-frame{width:min(1120px,100%);margin:0 auto}.site-header{display:flex;align-items:center;justify-content:space-between;gap:24px;min-height:72px;margin-bottom:38px;border-bottom:1px solid var(--line)}.brand{display:inline-flex;align-items:center;gap:10px;color:var(--ink);font-size:.96rem;font-weight:850;text-decoration:none}.brand-mark{display:grid;width:34px;height:34px;place-items:center;border-radius:6px;color:#fff;background:var(--teal);font-family:SFMono-Regular,Consolas,Liberation Mono,monospace;font-size:.78rem}.tool-tabs{display:flex;align-self:stretch;gap:6px}.tool-tabs a{display:grid;min-width:76px;place-items:center;border-bottom:3px solid transparent;color:var(--muted);font-size:.92rem;font-weight:800;text-decoration:none}.tool-tabs a:hover{color:var(--ink)}.tool-tabs a.active{border-bottom-color:var(--teal);color:var(--teal-dark)}.workspace{width:100%}.masthead{display:flex;align-items:end;justify-content:space-between;gap:24px;margin-bottom:20px}.eyebrow{margin:0 0 8px;color:var(--teal-dark);font-size:.78rem;font-weight:800;letter-spacing:0;text-transform:uppercase}h1{margin:0;color:var(--ink);font-size:3rem;line-height:1;letter-spacing:0}.mode-switch{display:grid;grid-template-columns:repeat(2,minmax(128px,1fr));gap:4px;padding:4px;border:1px solid var(--line);border-radius:8px;background:#ffffffbd}.mode-switch button,.ghost-button,.copy-button,.operation-bar button{min-height:40px;border:0;border-radius:6px;color:var(--ink);background:transparent;font-weight:800}.mode-switch button.active{color:#fff;background:var(--teal)}.options-bar,.operation-bar{display:flex;flex-wrap:wrap;gap:10px;margin-bottom:18px}.toggle{display:inline-flex;align-items:center;gap:9px;min-height:40px;padding:8px 12px;border:1px solid var(--line);border-radius:8px;background:#ffffffbd;color:var(--muted);font-weight:750}.toggle input{width:18px;height:18px;accent-color:var(--teal)}.operation-bar{padding:5px;border:1px solid var(--line);border-radius:8px;background:#ffffffb3}.operation-bar button{flex:1 1 130px;padding:0 13px;color:var(--muted);white-space:nowrap}.operation-bar button:hover{color:var(--ink);background:#e9efed}.operation-bar button.active{color:#fff;background:var(--teal)}.format-picker{min-width:0;margin:0 0 18px;padding:12px;border:1px solid var(--line);border-radius:8px;background:#ffffffb3}.format-picker legend{padding:0 6px;color:var(--ink);font-size:.9rem;font-weight:850}.format-picker legend span{margin-left:7px;color:var(--teal-dark);font-size:.78rem}.format-options{display:grid;grid-template-columns:repeat(3,minmax(0,1fr));gap:8px}.format-option{display:flex;align-items:center;gap:9px;min-width:0;min-height:44px;padding:8px 11px;border:1px solid #bfc9c6;border-radius:6px;color:var(--muted);font-size:.9rem;font-weight:800;background:var(--surface);cursor:pointer}.format-option:hover{border-color:#98aaa5;background:#f1f5f3}.format-option.active{border-color:var(--teal);color:var(--teal-dark);background:#e7f2ef}.format-option:focus-within{box-shadow:0 0 0 3px #0f766e29}.format-option input{width:17px;height:17px;flex:0 0 auto;margin:0;accent-color:var(--teal)}.format-option span{min-width:0;overflow-wrap:anywhere}.converter-grid{display:grid;grid-template-columns:repeat(2,minmax(0,1fr));gap:18px}.panel{display:flex;min-height:460px;flex-direction:column;border:1px solid var(--line);border-radius:8px;background:var(--surface);box-shadow:var(--shadow);overflow:hidden}.panel-header{display:flex;align-items:center;justify-content:space-between;gap:12px;min-height:64px;padding:14px 16px;border-bottom:1px solid var(--line)}.panel-header label{color:var(--ink);font-weight:850}.ghost-button{padding:0 14px;border:1px solid #bfc9c6;background:var(--surface-soft)}.ghost-button:hover{border-color:#98aaa5;background:#e9efed}.copy-button{padding:0 16px;color:#fff;background:var(--coral)}.copy-button:hover:not(:disabled){background:#a63825}textarea{width:100%;flex:1;min-height:340px;padding:18px;resize:vertical;border:0;outline:none;color:var(--ink);background:transparent;font-family:SFMono-Regular,Consolas,Liberation Mono,monospace;font-size:.96rem;line-height:1.65}textarea:focus{box-shadow:inset 0 0 0 3px #0f766e38}textarea[readonly]{background:#f8faf9}.error-message{margin:0;padding:12px 18px;border-top:1px solid #efb2a6;color:#962e1f;background:#fff0ed;font-weight:800}.status-strip{display:flex;flex-wrap:wrap;gap:10px;margin-top:18px}.status-strip span{min-height:34px;padding:8px 11px;border:1px solid var(--line);border-radius:8px;background:#ffffffbd;color:var(--muted);font-size:.9rem;font-weight:760}@media(max-width:780px){.app-shell{padding:0 14px 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