*,*:before,*:after{box-sizing:border-box}:root{--bg: #f4f6fb;--bg-accent: radial-gradient(1200px 500px at 80% -10%, rgba(79, 110, 247, .12), transparent 60%), radial-gradient(900px 400px at -10% 20%, rgba(16, 185, 129, .08), transparent 55%);--surface: #ffffff;--surface-2: #f1f4fa;--text: #17233b;--muted: #5b6b84;--border: #dfe6f1;--primary: #4f6ef7;--primary-strong: #3d5bf0;--primary-soft: rgba(79, 110, 247, .12);--accent: #10b981;--danger: #ef4444;--warn: #f59e0b;--shadow: 0 1px 2px rgba(23, 35, 59, .05), 0 8px 24px rgba(23, 35, 59, .06)}html[data-theme=dark]{--bg: #0d1220;--bg-accent: radial-gradient(1200px 500px at 80% -10%, rgba(79, 110, 247, .18), transparent 60%), radial-gradient(900px 400px at -10% 20%, rgba(16, 185, 129, .1), transparent 55%);--surface: #161d30;--surface-2: #1e2740;--text: #e9eefb;--muted: #97a3bd;--border: #273252;--primary: #6d86ff;--primary-strong: #5871ff;--primary-soft: rgba(109, 134, 255, .16);--accent: #34d399;--danger: #f87171;--warn: #fbbf24;--shadow: 0 1px 2px rgba(0, 0, 0, .4), 0 8px 24px rgba(0, 0, 0, .35)}html,body{margin:0;padding:0}body{font-family:Segoe UI,system-ui,-apple-system,Roboto,Helvetica Neue,Arial,PingFang SC,Microsoft YaHei,sans-serif;background-color:var(--bg);background-image:var(--bg-accent);background-repeat:no-repeat;color:var(--text);line-height:1.55;min-height:100vh;transition:background-color .25s ease,color .25s ease}h1,h2,h3{line-height:1.25}a{color:var(--primary);text-decoration:none}a:hover{text-decoration:underline}.container{width:min(1080px,calc(100% - 40px));margin:0 auto}.site-header{position:sticky;top:0;z-index:20;-webkit-backdrop-filter:blur(10px);backdrop-filter:blur(10px);background:color-mix(in srgb,var(--bg) 78%,transparent);border-bottom:1px solid var(--border)}.site-header .inner{display:flex;align-items:center;gap:14px;height:62px}.brand{display:flex;align-items:center;gap:10px;font-weight:700;font-size:1.15rem;color:var(--text);white-space:nowrap}.brand:hover{text-decoration:none}.brand .logo{display:grid;place-items:center;width:34px;height:34px;border-radius:9px;background:linear-gradient(135deg,var(--primary),var(--accent));color:#fff;font-size:17px;font-weight:800}.header-spacer{flex:1}.select,.input{background:var(--surface);border:1px solid var(--border);color:var(--text);border-radius:10px;padding:9px 12px;font-size:.95rem;font-family:inherit;outline:none;transition:border-color .15s ease,box-shadow .15s ease}.select:focus,.input:focus{border-color:var(--primary);box-shadow:0 0 0 3px var(--primary-soft)}.input[type=number]::-webkit-outer-spin-button,.input[type=number]::-webkit-inner-spin-button{-webkit-appearance:none;margin:0}.icon-btn{display:inline-grid;place-items:center;width:38px;height:38px;border-radius:10px;border:1px solid var(--border);background:var(--surface);color:var(--text);cursor:pointer;transition:border-color .15s ease,transform .1s ease}.icon-btn:hover{border-color:var(--primary)}.icon-btn:active{transform:scale(.95)}.icon-btn svg{width:19px;height:19px}.btn{display:inline-flex;align-items:center;justify-content:center;gap:8px;border:none;cursor:pointer;font-family:inherit;font-size:.98rem;font-weight:600;color:#fff;background:var(--primary);border-radius:11px;padding:11px 20px;transition:background .15s ease,transform .1s ease,box-shadow .15s ease}.btn:hover{background:var(--primary-strong)}.btn:active{transform:scale(.98)}.btn.secondary{background:var(--primary-soft);color:var(--primary)}.btn.secondary:hover{background:var(--primary-soft);filter:brightness(1.06)}.btn.block{width:100%}.chip-row{display:flex;flex-wrap:wrap;gap:8px}.chip{border:1px solid var(--border);background:var(--surface);color:var(--muted);border-radius:999px;padding:6px 13px;font-size:.88rem;cursor:pointer;font-family:inherit;transition:all .15s ease}.chip:hover{border-color:var(--primary);color:var(--primary)}.chip.active{background:var(--primary-soft);border-color:var(--primary);color:var(--primary);font-weight:600}.card{background:var(--surface);border:1px solid var(--border);border-radius:16px;box-shadow:var(--shadow);padding:22px}.tool-layout{display:grid;grid-template-columns:minmax(0,1fr) 300px;gap:22px;align-items:start}@media(max-width:860px){.tool-layout{grid-template-columns:1fr}}.page-head{margin:26px 0 20px}.page-head h1{margin:0 0 6px;font-size:1.65rem;display:flex;align-items:center;gap:12px}.page-head .desc{margin:0;color:var(--muted);max-width:70ch}.tool-icon-badge{display:inline-grid;place-items:center;width:46px;height:46px;border-radius:13px;background:var(--primary-soft);color:var(--primary);flex-shrink:0}.tool-icon-badge svg{width:24px;height:24px}.field-label{display:block;font-size:.85rem;font-weight:600;color:var(--muted);margin:0 0 6px 2px}.form-grid{display:grid;gap:16px}@media(min-width:640px){.form-grid.cols-2{grid-template-columns:1fr 1fr}.form-grid.cols-3{grid-template-columns:repeat(3,1fr)}}.result-box{background:var(--surface-2);border:1px solid var(--border);border-radius:12px;padding:14px 16px}.result-box .label{font-size:.82rem;color:var(--muted);font-weight:600}.result-box .value{font-size:1.45rem;font-weight:700;word-break:break-all;font-variant-numeric:tabular-nums}.result-box.primary{border-color:color-mix(in srgb,var(--primary) 45%,var(--border));background:var(--primary-soft)}.result-grid{display:grid;gap:10px}@media(min-width:480px){.result-grid.cols-2{grid-template-columns:1fr 1fr}.result-grid.cols-3{grid-template-columns:repeat(3,1fr)}}.error-text{color:var(--danger);font-size:.9rem;font-weight:600}.hint-text{color:var(--muted);font-size:.85rem}.divider{border:none;border-top:1px solid var(--border);margin:20px 0}.segmented{display:inline-flex;background:var(--surface-2);border:1px solid 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ease}.tool-card:hover{text-decoration:none;transform:translateY(-3px);border-color:var(--primary)}.tool-card .name{font-weight:700;font-size:1.04rem}.tool-card .brief{color:var(--muted);font-size:.9rem;flex:1}.calc-display{background:var(--surface-2);border:1px solid var(--border);border-radius:12px;padding:14px 16px;margin-bottom:14px;text-align:right;overflow:hidden}.calc-display .expression{font-family:ui-monospace,Cascadia Mono,Consolas,monospace;font-size:1.05rem;color:var(--muted);min-height:1.5em;word-break:break-all;white-space:pre-wrap}.calc-display .preview{font-size:.95rem;color:var(--muted);opacity:.85;min-height:1.4em;word-break:break-all;font-variant-numeric:tabular-nums}.calc-display .output{font-size:clamp(1.6rem,4.5vw,2.3rem);font-weight:700;word-break:break-all;font-variant-numeric:tabular-nums;overflow-wrap:anywhere}.keypad{display:grid;grid-template-columns:repeat(4,1fr);gap:9px}.keypad button{height:52px;border-radius:11px;border:1px solid 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li::marker{color:var(--primary);font-weight:700}.data-table{width:100%;border-collapse:collapse;font-size:.93rem}.data-table th,.data-table td{text-align:left;padding:9px 12px;border-bottom:1px solid var(--border)}.data-table th{color:var(--muted);font-size:.83rem;text-transform:uppercase;letter-spacing:.03em}.data-table td.num{font-variant-numeric:tabular-nums;font-family:inherit}.site-footer{border-top:1px solid var(--border);padding:26px 0 34px;margin-top:30px;color:var(--muted);font-size:.9rem}.site-footer .inner{display:flex;flex-wrap:wrap;gap:10px;justify-content:space-between;align-items:center}