:root{color-scheme:dark;--bg:#0a0a1a;--panel:#111126;--panel-2:#15152c;--text:#f0f0f8;--muted:#aaa9c4;--soft:#77768f;--purple:#8474ff;--purple-2:#5e4de4;--cyan:#00d2ff;--green:#73e6ba;--danger:#ff9fae;--line:#a197e62e;--line-strong:#a197e657;--shadow:0 28px 80px #00000057;--radius:22px;--content:1104px;--header:68px;font-family:Inter,ui-sans-serif,system-ui,-apple-system,BlinkMacSystemFont,Segoe UI,sans-serif}*{box-sizing:border-box}html{scroll-behavior:smooth;scroll-padding-top:calc(var(--header) + 22px);background:var(--bg)}body{min-width:320px;min-height:100vh;color:var(--text);background:radial-gradient(900px 560px at -10% 3%, #684ce638, transparent 68%), radial-gradient(780px 560px at 105% 50%, #00d2ff17, transparent 70%), var(--bg);margin:0;font-size:16px;line-height:1.7;overflow-x:hidden}body:before{content:"";pointer-events:none;opacity:.12;background-image:linear-gradient(#ffffff06 1px,#0000 1px),linear-gradient(90deg,#ffffff05 1px,#0000 1px);background-size:72px 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var(--cyan);background:#00d2ff0e;border-radius:0 18px 18px 0;padding:clamp(22px,4vw,34px)}.answer-box p:last-child{margin-bottom:0}.formula{color:#e1dcff;background:#8474ff17;border:1px solid #8474ff47;border-radius:12px;align-items:center;min-height:48px;padding:10px 16px;font-family:Cambria Math,Georgia,serif;font-size:clamp(1.02rem,2vw,1.22rem);display:inline-flex}.pill{border:1px solid var(--line);color:var(--muted);border-radius:999px;align-items:center;gap:7px;padding:6px 11px;font-size:.82rem;display:inline-flex}.button{border:1px solid var(--line-strong);min-height:46px;color:var(--text);background:#8474ff1f;border-radius:12px;justify-content:center;align-items:center;gap:9px;padding:10px 18px;font-weight:750;text-decoration:none;transition:transform .2s,border-color .2s,background 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span{color:var(--cyan)}.site-nav{align-items:center;gap:4px;display:flex}.site-nav a{color:#c9c7da;border-radius:10px;align-items:center;min-height:42px;padding:8px 12px;font-size:.92rem;font-weight:650;text-decoration:none;display:inline-flex}.site-nav a:hover,.site-nav a[aria-current=page]{color:#fff;background:#ffffff0e}.language-switcher,.language-switcher details{position:relative}.language-switcher summary{border:1px solid var(--line);color:#d8d6e7;cursor:pointer;border-radius:10px;align-items:center;gap:7px;min-height:42px;padding:8px 11px;font-size:.86rem;font-weight:650;list-style:none;display:inline-flex}.language-switcher summary::-webkit-details-marker{display:none}.language-switcher summary:after{content:"▾";color:var(--soft);font-size:.7rem}.language-menu{z-index:130;border:1px solid var(--line-strong);width:min(310px,100vw - 32px);max-height:min(480px,70vh);box-shadow:var(--shadow);background:#111126;border-radius:14px;grid-template-columns:repeat(2,minmax(0,1fr));gap:4px;padding:9px;display:grid;position:absolute;inset-block-start:calc(100% + 8px);inset-inline-end:0;overflow:auto}.language-menu a{color:#d8d6e7;border-radius:9px;justify-content:space-between;align-items:center;gap:8px;min-height:44px;padding:8px 10px;text-decoration:none;display:flex}.language-menu a:hover,.language-menu a[aria-current=page]{color:#fff;background:#00d2ff14}.language-menu small{color:var(--soft);font-size:.7rem}.footer-group .language-switcher summary{justify-content:space-between;width:100%}.footer-group .language-menu{inset-inline:0 auto}[dir=rtl] .formula,[dir=rtl] .input-row,[dir=rtl] .result-line,[dir=rtl] .chart{direction:ltr}[dir=rtl] .field label,[dir=rtl] .field-error,[dir=rtl] .result-label,[dir=rtl] .calculator-head,[dir=rtl] .graph-head{text-align:start;direction:rtl}[dir=rtl] 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