/* © 2026 ToolkitBee – https://toolkitbee.com – all rights reserved */
:root{--bg: #f6f7fb;--surface: #ffffff;--text: #1c2030;--muted: #5d6477;--border: #e2e5ee;--accent: #2f5bea;--accent-soft: #e8eefe;--accent-2: #f59e0b;--radius: 14px;--shadow: 0 1px 2px rgba(20, 30, 60, .06), 0 4px 16px rgba(20, 30, 60, .05);color-scheme:light}@media(prefers-color-scheme:dark){:root{--bg: #11131a;--surface: #1a1d27;--text: #e8eaf1;--muted: #a0a6b8;--border: #2c3040;--accent: #7f9cff;--accent-soft: #232b48;--accent-2: #fbbf24;--shadow: none;color-scheme:dark}}*{box-sizing:border-box}html{-webkit-text-size-adjust:100%}body{margin:0;background:var(--bg);color:var(--text);font:16px/1.6 system-ui,-apple-system,Segoe UI,Roboto,Noto Sans,Noto Sans Devanagari,Nirmala UI,sans-serif}a{color:var(--accent)}h1{font-size:clamp(1.6rem,4vw,2.2rem);line-height:1.25;margin:.4em 0 .3em}h2{font-size:1.25rem;margin:1.8em 0 .6em}.wrap{max-width:1040px;margin:0 auto;padding:0 16px}.lead{color:var(--muted);font-size:1.05rem;max-width:60ch}.visually-hidden{position:absolute;width:1px;height:1px;overflow:hidden;clip:rect(0 0 0 0)}.site-header{background:var(--surface);border-bottom:1px solid var(--border)}.header-inner{display:flex;align-items:center;justify-content:space-between;height:60px}.logo{display:flex;align-items:center;gap:10px;font-weight:700;font-size:1.2rem;color:var(--text);text-decoration:none}.logo-mark{display:block;width:34px;height:34px}.lang-switch{padding:6px 14px;border:1px solid var(--border);border-radius:999px;text-decoration:none;font-weight:600}.lang-switch:hover{background:var(--accent-soft)}.site-footer{margin-top:64px;padding:28px 0;border-top:1px solid var(--border);color:var(--muted);font-size:.9rem}.footer-nav{display:flex;flex-wrap:wrap;gap:8px 20px;margin-bottom:8px}.crumbs{margin-top:20px;font-size:.9rem;color:var(--muted)}.hero{padding:32px 0 8px}.grid{display:grid;grid-template-columns:repeat(auto-fill,minmax(230px,1fr));gap:14px}.card{display:flex;flex-direction:column;gap:4px;padding:18px;background:var(--surface);border:1px solid var(--border);border-radius:var(--radius);box-shadow:var(--shadow);color:var(--text);text-decoration:none;transition:border-color .15s,transform .15s}.card:hover{border-color:var(--accent);transform:translateY(-2px)}.card-icon{font-size:1.6rem}.card-title{font-weight:700}.card-desc{color:var(--muted);font-size:.88rem;display:-webkit-box;-webkit-line-clamp:2;-webkit-box-orient:vertical;overflow:hidden}.calc{display:grid;grid-template-columns:1fr 1fr;gap:24px;margin:24px 0;padding:24px;background:var(--surface);border:1px solid var(--border);border-radius:var(--radius);box-shadow:var(--shadow)}@media(max-width:720px){.calc{grid-template-columns:1fr;padding:18px}}.calc-form{display:flex;flex-direction:column;gap:14px}.field label{display:block;font-weight:600;font-size:.92rem;margin-bottom:6px}.field input,.field select{width:100%;padding:11px 12px;font:inherit;font-size:1.05rem;color:var(--text);background:var(--bg);border:1px solid var(--border);border-radius:10px}.field input:focus,.field select:focus{outline:2px solid var(--accent);outline-offset:1px;border-color:transparent}.calc-results{display:flex;flex-direction:column;gap:10px}.result{display:flex;justify-content:space-between;align-items:baseline;gap:12px;padding:10px 0;border-bottom:1px dashed var(--border)}.result-label{color:var(--muted)}.result-value{font-weight:700;text-align:right;font-variant-numeric:tabular-nums;overflow-wrap:anywhere}.result.primary{flex-direction:column;align-items:flex-start;gap:2px;padding:16px;background:var(--accent-soft);border:0;border-radius:12px}.result.primary .result-label{color:var(--text);font-weight:600}.result.primary .result-value{font-size:clamp(1.6rem,5vw,2.1rem);color:var(--accent);text-align:left;line-height:1.2}.bar{margin-top:6px}.bar-track{display:flex;height:12px;border-radius:999px;overflow:hidden;background:var(--border)}.bar-a{background:var(--accent);transition:width .3s}.bar-b{background:var(--accent-2);transition:width .3s}.bar-legend{display:flex;gap:18px;margin-top:8px;font-size:.88rem;color:var(--muted)}.dot{display:inline-block;width:10px;height:10px;border-radius:50%;margin-right:6px}.dot-a{background:var(--accent)}.dot-b{background:var(--accent-2)}.calc.wide{grid-template-columns:1fr}.calc.wide .calc-form{display:grid;grid-template-columns:1fr 1fr;gap:12px 20px}.calc.wide .calc-form>.field:has(textarea),.calc.wide .calc-form>.field:has(select){grid-column:1 / -1}@media(max-width:720px){.calc.wide .calc-form{grid-template-columns:1fr}}.calc.wide .calc-results:has(.result){display:grid;grid-template-columns:repeat(3,1fr);gap:10px}@media(max-width:520px){.calc.wide .calc-results:has(.result){grid-template-columns:repeat(2,1fr)}}.calc.wide .result{flex-direction:column;align-items:flex-start;gap:2px;padding:12px 14px;background:var(--bg);border:1px solid var(--border);border-radius:10px}.calc.wide .result-value{font-size:1.4rem;color:var(--accent);text-align:left}.field textarea,.output textarea{width:100%;padding:12px;font:inherit;color:var(--text);resize:vertical;background:var(--bg);border:1px solid var(--border);border-radius:10px}.field textarea:focus{outline:2px solid var(--accent);outline-offset:1px;border-color:transparent}.check{display:flex;align-items:center;gap:10px;font-size:.95rem;cursor:pointer}.check input{width:18px;height:18px;accent-color:var(--accent)}.actions{display:flex;flex-wrap:wrap;gap:8px}.btn{padding:9px 16px;font:inherit;font-weight:600;font-size:.95rem;color:var(--text);cursor:pointer;background:var(--surface);border:1px solid var(--border);border-radius:999px}.btn:hover{border-color:var(--accent)}.btn[aria-pressed=true],.btn-primary{background:var(--accent);border-color:var(--accent);color:#fff}.output-head{display:flex;justify-content:space-between;align-items:center;margin-bottom:6px;font-weight:600;font-size:.92rem}.output textarea{background:var(--accent-soft);border-color:transparent}.field .label{display:block;font-weight:600;font-size:.92rem;margin-bottom:6px}.drop{position:relative;display:flex;flex-direction:column;align-items:center;justify-content:center;gap:6px;min-height:130px;padding:16px;text-align:center;color:var(--muted);cursor:pointer;background:var(--bg);border:2px dashed var(--border);border-radius:12px;overflow-wrap:anywhere}.drop:hover,.drop:focus-within{border-color:var(--accent);color:var(--text)}.drop input{position:absolute;inset:0;width:100%;height:100%;opacity:0;cursor:pointer}.drop-icon{display:grid;place-items:center;width:40px;height:40px;border-radius:50%;background:var(--accent-soft);color:var(--accent);font-size:1.2rem}.range-value{float:right;color:var(--accent);font-variant-numeric:tabular-nums}.field input[type=range]{width:100%;padding:0;background:none;border:0;accent-color:var(--accent)}.preview{display:grid;place-items:center;background:repeating-conic-gradient(var(--border) 0 25%,transparent 0 50%) 0 0 / 16px 16px;border-radius:12px;overflow:hidden}.preview img{display:block;max-width:100%;max-height:360px}.preview:has(img[hidden]){display:none}.btn-block{display:block;text-align:center;text-decoration:none}.btn-block[hidden]{display:none}.calc.busy .calc-results>:not(.working){opacity:.5;transition:opacity .2s}.working{display:none;margin:0;font-weight:600;color:var(--accent)}.calc.busy .working{display:block}.error{margin:0;padding:12px 14px;border-radius:10px;background:#fdecec;color:#a4262c;font-weight:600}@media(prefers-color-scheme:dark){.error{background:#3a1d20;color:#ffb3b8}}.filelist{list-style:none;margin:10px 0 0;padding:0;display:flex;flex-direction:column;gap:6px}.filelist li{display:flex;align-items:center;gap:6px;padding:6px 8px 6px 12px;background:var(--bg);border:1px solid var(--border);border-radius:10px;font-size:.9rem}.filelist li span{flex:1;min-width:0;overflow:hidden;text-overflow:ellipsis;white-space:nowrap}.icon-btn{flex:none;width:32px;height:32px;font:inherit;color:var(--text);background:var(--surface);border:1px solid var(--border);border-radius:8px;cursor:pointer}.icon-btn:hover{border-color:var(--accent);color:var(--accent)}.gallery{display:grid;grid-template-columns:repeat(auto-fill,minmax(110px,1fr));gap:10px}.thumb{display:flex;flex-direction:column;gap:4px;font-size:.85rem;font-weight:600;text-decoration:none}.thumb img{width:100%;aspect-ratio:3 / 4;object-fit:contain;background:#fff;border:1px solid var(--border);border-radius:8px}.mono textarea,.mono .output textarea{font-family:ui-monospace,SFMono-Regular,Consolas,Liberation Mono,monospace;font-size:.92rem;tab-size:2}.calc.wide .error{grid-column:1 / -1}.kc-wrap{grid-template-columns:minmax(0,420px) minmax(0,1fr);align-items:start}@media(max-width:720px){.kc-wrap{grid-template-columns:1fr}}.kc{display:flex;flex-direction:column;gap:10px}.kc-top{display:flex;gap:8px}.kc-display{padding:14px 16px;background:var(--bg);border:1px solid var(--border);border-radius:12px;text-align:right;min-height:96px}.kc-expr{min-height:1.6em;font-size:1.15rem;color:var(--muted);overflow-wrap:anywhere;font-variant-numeric:tabular-nums}.kc-result{display:block;font-size:clamp(1.8rem,7vw,2.4rem);font-weight:700;line-height:1.2;overflow-wrap:anywhere;font-variant-numeric:tabular-nums;color:var(--muted)}.kc-result.done{color:var(--text)}.kc-basic{display:grid;grid-template-columns:repeat(4,1fr);gap:8px}.kc-sci{display:grid;grid-template-columns:repeat(5,1fr);gap:6px}.kc-sci[hidden]{display:none}.kc-key{height:56px;font:inherit;font-size:1.25rem;font-weight:600;color:var(--text);cursor:pointer;background:var(--surface);border:1px solid var(--border);border-radius:12px;touch-action:manipulation}.kc-sci .kc-key{height:44px;font-size:1rem;background:var(--bg)}.kc-key:hover{border-color:var(--accent)}.kc-key:active{transform:scale(.97)}.kc-op{color:var(--accent);background:var(--accent-soft);border-color:transparent}.kc-fn{color:#c2410c}.kc-eq{background:var(--accent);border-color:var(--accent);color:#fff}.kc-history h2{margin:0;font-size:1rem}.kc-history ol{list-style:none;margin:8px 0 0;padding:0;display:flex;flex-direction:column;gap:4px;max-height:420px;overflow-y:auto}.kc-history li button{width:100%;padding:8px 10px;font:inherit;font-variant-numeric:tabular-nums;text-align:right;color:var(--text);cursor:pointer;background:var(--bg);border:1px solid transparent;border-radius:8px;overflow-wrap:anywhere}.kc-history li button:hover{border-color:var(--accent)}.content{max-width:760px}.content ol{padding-left:1.3em}.content li{margin:4px 0}.formula{padding:14px 16px;background:var(--surface);border-left:4px solid var(--accent);border-radius:8px;overflow-x:auto}details{background:var(--surface);border:1px solid var(--border);border-radius:10px;margin:8px 0;padding:0 16px}summary{cursor:pointer;font-weight:600;padding:12px 0}details p{margin:0 0 14px;color:var(--muted)}.prose h2{font-size:1.1rem}