:root{--bg:#f5f7fb;--card:#fff;--soft:#edf3fa;--text:#172033;--muted:#687388;--border:#dce2eb;--blue:#17365d;--input:#fff;--shadow:0 8px 24px rgba(24,49,83,.08);color-scheme:light}html[data-theme=dark]{--bg:#0f141c;--card:#171e28;--soft:#202b38;--text:#edf2f7;--muted:#a8b3c2;--border:#334052;--blue:#62a6ff;--input:#111821;--shadow:0 8px 24px rgba(0,0,0,.22);color-scheme:dark}*{box-sizing:border-box}body{margin:0;background:var(--bg);font-family:system-ui,-apple-system,"Segoe UI",Roboto,sans-serif;color:var(--text)}.app{max-width:760px;margin:auto;min-height:100vh;padding-bottom:18px}.top{position:sticky;top:0;z-index:20;display:grid;grid-template-columns:1fr auto 1fr;align-items:center;gap:8px;padding:10px 12px;border-bottom:1px solid var(--border);background:var(--card)}.back{color:var(--blue);font-size:13px;font-weight:800;text-decoration:none}.brand{text-align:center;font-size:24px;font-weight:800}.brand .gas{color:var(--blue)}.controls{display:flex;justify-content:flex-end;gap:5px}.control{min-width:0;max-width:78px;padding:7px 5px;border:1px solid var(--border);border-radius:9px;background:var(--input);color:var(--text);font:inherit;font-size:10px}main{padding:18px 14px 44px}.intro{margin:0 2px 16px}.intro h1{margin:0 0 6px;font-size:23px}.intro p{margin:0;color:var(--muted);font-size:13px}.tool-grid{display:grid;grid-template-columns:repeat(2,minmax(0,1fr));gap:12px}.tool{min-height:116px;display:flex;flex-direction:column;justify-content:space-between;padding:17px;border:1px solid var(--border);border-radius:17px;background:var(--card);box-shadow:var(--shadow);color:var(--text);text-decoration:none}.tool:hover{border-color:var(--blue);transform:translateY(-1px)}.tool:focus-visible{outline:3px solid rgba(37,99,235,.25);outline-offset:2px}.tool-head{display:grid;grid-template-columns:48px minmax(0,1fr);align-items:center;gap:13px}.tool-icon{width:48px;height:48px;display:grid;place-items:center;border:1px solid color-mix(in srgb,var(--blue) 16%,var(--border));border-radius:15px;background:linear-gradient(145deg,var(--card),var(--soft));color:var(--blue);box-shadow:inset 0 1px 0 rgba(255,255,255,.55),0 4px 12px rgba(24,49,83,.08)}.tool-icon svg{width:34px;height:34px;fill:none;stroke:currentColor;stroke-width:1.8;stroke-linecap:round;stroke-linejoin:round}.tool-icon svg .detail{opacity:.58;stroke-width:1.5}.tool-icon svg .icon-dot{fill:currentColor;stroke:none;opacity:.62}.tool strong{font-size:15px;line-height:1.3}.tool span{margin-top:14px;color:var(--blue);font-size:12px;font-weight:800}.placeholder-card{padding:18px;border:1px solid var(--border);border-radius:18px;background:var(--card);box-shadow:var(--shadow)}.placeholder-card h1{margin:0 0 10px;font-size:22px;line-height:1.25}.placeholder-card p{margin:0;color:var(--muted);font-size:13px;line-height:1.5}.state{display:inline-flex;margin-top:16px;padding:7px 10px;border-radius:999px;background:var(--soft);color:var(--blue);font-size:11px;font-weight:800}@media(min-width:561px){.tool[href$="flowmeter-correction.html"] strong{max-width:205px}}@media(max-width:560px){.top{grid-template-columns:auto 1fr auto}.brand{font-size:21px}.tool-grid{grid-template-columns:1fr}.tool{min-height:96px}.placeholder-card h1{font-size:20px}}

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