/* SimpleMathCalc styles (based on SimpleFitCalc) — mobile-first. Tokens first; change colors here. */
:root{--accent:#4f46e5;--accent-dark:#4338ca;--accent-tint:#eef2ff;--warm:#f59e0b;--warm-dark:#b45309;--warm-tint:#fffbeb;
--bg:#f8fafc;--card:#fff;--text:#111827;--muted:#4b5563;--border:#e5e7eb;--err:#b91c1c;--radius:12px}
*{box-sizing:border-box}
html{scroll-padding-top:5rem}
body{margin:0;font-family:system-ui,-apple-system,"Segoe UI",Roboto,sans-serif;font-size:16px;background:var(--bg);color:var(--text);line-height:1.65;
  min-height:100vh;display:flex;flex-direction:column} /* flex column: footer sits at bottom, no blank band below */
main{flex:1 0 auto;width:100%;padding:1.25rem 0 2rem}
a{color:var(--accent-dark)}
.container{max-width:960px;margin:0 auto;padding:0 1rem}
main.container{max-width:960px}
main>section:not(.cat),main>.intro,main>aside{max-width:760px}
.logo b{font-weight:800}
/* ===== Header (sticky, solid background: no backdrop-filter to avoid blank-top repaint glitch) ===== */
.site-header{position:sticky;top:0;z-index:50;background:var(--accent-tint);border-bottom:1px solid #e0e7ff}
.hdr{display:flex;align-items:center;justify-content:space-between;flex-wrap:wrap;padding:.5rem 1rem;min-height:60px}
.logo{display:flex;align-items:center;gap:.5rem;font-weight:800;text-decoration:none;color:var(--text);font-size:1.15rem;min-height:44px}
.logo span{color:var(--accent-dark)}
.menu-btn{display:flex;flex-direction:column;justify-content:center;gap:5px;width:44px;height:44px;padding:10px;background:#fff;border:1px solid var(--border);border-radius:10px}
.menu-btn span{display:block;height:2px;background:var(--text);border-radius:2px}
.nav{display:none;width:100%;flex-direction:column;padding:.5rem 0}
.nav.open{display:flex}
.nav a,.dd summary{display:flex;align-items:center;min-height:44px;padding:0 .75rem;text-decoration:none;color:var(--text);font-weight:600;border-radius:8px;cursor:pointer}
.dd summary{list-style:none}.dd summary::-webkit-details-marker{display:none}
.dd summary::after{content:"▾";margin-left:.35rem;color:var(--muted)}
.dd-menu{display:flex;flex-direction:column;padding-left:.75rem}
.dd-menu a{font-weight:500;color:var(--muted)}
.nav a[aria-current=page]{color:var(--accent-dark);background:#fff}
.nav a:hover,.dd summary:hover{background:#fff}
/* ===== Hero / content ===== */
.hero{background:linear-gradient(135deg,var(--accent-tint),var(--warm-tint));border-bottom:1px solid var(--border);padding:2rem 0 1.75rem}
.hero h1{margin:0 0 .5rem}.promise{margin:0;font-size:1.1rem;color:var(--muted);max-width:640px}
h1{font-size:2rem;line-height:1.2;margin:.25rem 0 .75rem}
h2{font-size:1.35rem;margin-top:2rem}h3{font-size:1.1rem;margin:1.25rem 0 .4rem}
.intro{color:var(--muted);font-size:1.075rem}
.breadcrumb{font-size:1rem;color:var(--muted);margin:.25rem 0}.breadcrumb a{color:var(--muted)}
.card{background:var(--card);border:1px solid var(--border);border-radius:var(--radius);padding:1.25rem;margin:1rem 0}
.cat h2{display:flex;align-items:center;gap:.5rem}
.grid{display:grid;gap:1rem;grid-template-columns:1fr}
.grid .card{margin:0}
.tool-card{display:block;text-decoration:none;color:inherit;transition:border-color .15s,box-shadow .15s}
.tool-card:hover{border-color:var(--accent);box-shadow:0 4px 14px rgba(79,70,229,.14)}
.tool-card .icon{color:var(--accent);background:var(--accent-tint);border-radius:10px;padding:6px;width:40px;height:40px}
.tool-card h3{margin:.5rem 0 .3rem;color:var(--accent-dark)}
.tool-card p{margin:0;color:var(--muted);font-size:1rem}
/* ===== Forms ===== */
fieldset{border:0;padding:0;margin:0 0 1rem}
legend,label{font-weight:600;font-size:1rem;display:block;margin-bottom:.3rem}
.hint{font-size:1rem;color:var(--muted);font-weight:400}
.field{margin-bottom:1rem}
.row{display:flex;gap:.75rem}.row>*{flex:1}
input[type=number],select{width:100%;min-height:44px;padding:.6rem .75rem;font-size:1rem;border:1px solid #cbd5e1;border-radius:8px;background:#fff;color:var(--text)}
input::placeholder{color:#9ca3af}
input:focus,select:focus{outline:2px solid var(--accent);outline-offset:1px}
.toggle{display:inline-flex;flex-wrap:wrap;border:1px solid #cbd5e1;border-radius:8px;overflow:hidden}
.toggle label{margin:0;font-weight:500;cursor:pointer;position:relative}
.toggle span{display:flex;align-items:center;min-height:44px;padding:0 .9rem}
.toggle input{position:absolute;opacity:0}
.toggle input:checked+span{background:var(--accent);color:#fff;font-weight:700}
.toggle input:focus-visible+span{outline:2px solid var(--warm)}
.buttons{display:flex;gap:.75rem}
button{min-height:44px;padding:.7rem 1.4rem;font-size:1rem;border-radius:8px;border:1px solid var(--accent);cursor:pointer;font-weight:600}
.btn-primary{background:var(--accent);color:#fff}.btn-primary:hover{background:var(--accent-dark)}
.btn-secondary{background:#fff;color:var(--accent-dark)}
.error{color:var(--err);background:#fef2f2;border:1px solid #fecaca;border-radius:8px;padding:.6rem .8rem;margin:0 0 1rem}
.hidden{display:none!important}
/* ===== Results ===== */
.result{border:2px solid var(--accent);background:#f5f7ff}
.result-ph{color:var(--muted);text-align:center;border-style:dashed;display:none}
.result .big{font-size:2.4rem;font-weight:800;color:var(--accent-dark);line-height:1.15;font-variant-numeric:tabular-nums}
.result .label{color:var(--muted);font-size:1rem}
table{width:100%;border-collapse:collapse;margin-top:.75rem;font-size:1rem}
th,td{text-align:left;padding:.5rem;border-bottom:1px solid var(--border);vertical-align:middle}
td{text-decoration:none;font-variant-numeric:tabular-nums}
.formula{background:#f3f4f6;padding:.75rem;border-radius:8px;overflow-x:auto;font-family:ui-monospace,monospace;font-size:.95rem}
/* BMI gauge */
.gauge{position:relative;margin:1rem 0 1.6rem}
.gauge-bar{display:flex;height:14px;border-radius:7px;overflow:hidden}
.gauge-bar i{display:block;height:100%}
.gauge-marker{position:absolute;top:-6px;width:4px;height:26px;background:var(--text);border-radius:2px;transform:translateX(-50%)}
.gauge-labels{position:relative;height:1.4rem;font-size:.875rem;color:var(--muted)}
.gauge-labels span{position:absolute;transform:translateX(-50%);top:4px}
/* Macro donut */
.donut-wrap{display:flex;align-items:center;gap:1.25rem;flex-wrap:wrap;margin-top:1rem}
.donut{width:130px;height:130px;border-radius:50%;position:relative}
.donut::after{content:"";position:absolute;inset:26px;background:#f5f7ff;border-radius:50%}
.legend{list-style:none;padding:0;margin:0;font-size:1rem}.legend li{display:flex;align-items:center;gap:.5rem}
.swatch{width:14px;height:14px;border-radius:3px;display:inline-block}
/* Calorie goal bars */
.bar{height:8px;border-radius:4px;background:var(--accent);margin-top:4px;min-width:4px}
.bar.warmb{background:var(--warm)}
.warn{background:var(--warm-tint);border:1px solid #fdba74;border-radius:8px;padding:.6rem .8rem;color:#7c2d12}
.disclaimer{background:#fff;border-left:4px solid var(--warm);padding:.75rem 1rem;border-radius:6px;font-size:1rem;margin:1rem 0}
.sources ol{padding-left:1.2rem;font-size:.95rem}.sources li{margin-bottom:.4rem;word-break:break-word}
.faq details{background:#fff;border:1px solid var(--border);border-radius:8px;padding:.25rem .9rem;margin:.5rem 0}
.faq summary{font-weight:600;cursor:pointer;min-height:44px;display:flex;align-items:center}
.related ul{padding-left:1.2rem}.related li{margin-bottom:.35rem}
/* ===== Ads: hidden until AdSense is approved. Remove this rule (or set display:flex) to show slots. ===== */
.ad-slot{display:none}
/* ===== Footer ===== */
.site-footer{flex-shrink:0;border-top:3px solid var(--accent);background:#0f172a;color:#cbd5e1;padding:1.75rem 0 1rem;font-size:1rem}
.site-footer a{color:#e2e8f0;text-decoration:none}.site-footer a:hover{text-decoration:underline}
.foot-cols{display:grid;grid-template-columns:1fr 1fr;gap:1rem}
.foot-cols h3{color:#fff;font-size:1rem;margin:0 0 .4rem}
.foot-cols a{display:block;padding:.3rem 0}
.foot-disc{border-top:1px solid #334155;padding-top:1rem;margin-top:1.25rem}
/* ===== Larger screens ===== */
@media (min-width:640px){.grid{grid-template-columns:1fr 1fr}h1{font-size:2.25rem}.foot-cols{grid-template-columns:repeat(3,1fr)}}
@media (min-width:900px){
  .grid{grid-template-columns:repeat(3,1fr)}
  .menu-btn{display:none}
  .nav{display:flex;flex-direction:row;width:auto;padding:0;gap:.15rem;align-items:center}
  .dd{position:relative}
  .dd-menu{position:absolute;top:100%;left:0;min-width:230px;background:#fff;border:1px solid var(--border);border-radius:10px;padding:.35rem;box-shadow:0 10px 25px rgba(0,0,0,.08)}
  .calc-wrap{display:grid;grid-template-columns:1fr 1fr;gap:1.25rem;align-items:start}
  .calc-wrap>.card{margin:1rem 0}
  .calc-wrap .result,.calc-wrap .result-ph{position:sticky;top:5rem}
  .result-ph{display:block}
}
input[type=date],input[type=time]{width:100%;min-height:44px;padding:.6rem .75rem;font-size:1rem;border:1px solid #cbd5e1;border-radius:8px;background:#fff;color:var(--text);font-family:inherit}
.hub-intro{max-width:760px}
.stack{display:flex;height:16px;border-radius:8px;overflow:hidden;margin:.75rem 0}.stack i{display:block;height:100%}
.warn-cell{color:#7c2d12;background:var(--warm-tint);font-size:1rem}

@media (min-width:900px){.foot-cols{grid-template-columns:repeat(6,1fr)}}
.cat h2 a,.foot-cols h3 a{color:inherit;text-decoration:none}.cat h2 a:hover{text-decoration:underline}
.dd-hub{font-weight:700!important;color:var(--accent-dark)!important}
.home-about{max-width:760px}
/* Desktop header: one row (logo + menu). */
@media (min-width:900px){.hdr{flex-wrap:nowrap}.nav a,.dd summary{padding:0 .5rem;font-size:1rem}.nav{gap:0}.nav-all{display:none!important}}
/* ===== Math hub additions ===== */
input[type=text]{width:100%;min-height:44px;padding:.6rem .75rem;font-size:1rem;border:1px solid #cbd5e1;border-radius:8px;background:#fff;color:var(--text);font-family:inherit}
textarea{width:100%;min-height:88px;padding:.6rem .75rem;font-size:1rem;border:1px solid #cbd5e1;border-radius:8px;font-family:inherit}
.dyn-row{display:grid;grid-template-columns:1fr auto;gap:.5rem;margin-bottom:.6rem;align-items:end}
.dyn-row .field{margin:0}
.grade-row{grid-template-columns:1fr 1fr auto}.grade-row .name{grid-column:1/-1}
.btn-small{padding:.4rem .8rem}
.add-btn{margin:.25rem 0 1rem}
.frac{display:flex;flex-direction:column;gap:.35rem;max-width:130px}
.frac-line{height:2px;background:var(--text)}
.frac-wrap{display:flex;flex-wrap:wrap;align-items:center;gap:.75rem}
.pbar{height:18px;background:#e5e7eb;border-radius:9px;overflow:hidden;margin:.75rem 0 .3rem}
.pbar i{display:block;height:100%;background:var(--accent);border-radius:9px}
.pbar.dec i{background:var(--warm)}
.cmp{display:grid;grid-template-columns:auto 1fr;gap:.4rem .6rem;align-items:center;margin-top:.75rem;font-size:1rem}
.cmp .bar{height:14px}
.pie{width:120px;height:120px;border-radius:50%;margin:.75rem 0;border:2px solid var(--accent)}
.dots{position:relative;height:36px;margin:1rem .5rem .5rem;border-bottom:2px solid #cbd5e1}
.dots i{position:absolute;bottom:-6px;width:10px;height:10px;border-radius:50%;background:var(--accent);transform:translateX(-50%);opacity:.75}
.dots b{position:absolute;bottom:-14px;width:3px;height:30px;background:var(--warm);transform:translateX(-50%)}
.hero .promise{max-width:700px}
.tool-card .icon{display:block}
@media (min-width:900px){.grade-row{grid-template-columns:2fr 1fr 1fr auto}.grade-row .name{grid-column:auto}}
/* Audit round 2: 3-field fraction rows, step lists, top links */
.row>*{min-width:0}
.steps-h{margin:1rem 0 .4rem;font-size:1.05rem}
.steps{margin:.25rem 0 0;padding-left:1.25rem}.steps li{margin:.3rem 0;overflow-wrap:anywhere}
.toplink{margin:.25rem 0 .5rem;padding:.6rem .8rem;background:var(--accent-tint);border-radius:8px}
/* Batch 1: dates, converters, text tools */
.thermo{position:relative;height:16px;border-radius:8px;background:linear-gradient(90deg,#60a5fa,#a5b4fc 40%,#fcd34d 70%,#f87171);margin:1rem 0 2.2rem}
.thermo i{position:absolute;top:-5px;bottom:-5px;left:0;border-right:4px solid var(--text);border-radius:0}
.thermo span{position:absolute;top:22px;transform:translateX(-50%);font-size:.875rem;color:var(--muted);white-space:nowrap}
.mgrid{margin-top:1rem;max-width:300px}.mgrid b{display:block;margin-bottom:.3rem}
.mgrid div{display:grid;grid-template-columns:repeat(7,1fr);gap:2px;text-align:center}
.mgrid em{font-style:normal;font-weight:700;color:var(--muted);font-size:.875rem}
.mgrid span{padding:.2rem 0;border-radius:6px;font-size:.95rem}.mgrid span.on{background:var(--accent);color:#fff;font-weight:700}
.kw div{margin:.35rem 0}.kw span{font-size:1rem}
tr.hl th,tr.hl td{background:var(--accent-tint);font-weight:700}
.conv-table{max-height:none}
.swap-btn{margin:0 0 1rem}
textarea#text{min-height:200px}
.hub-tools{margin-top:1rem}
/* Batch 2 */
.tc-row{grid-template-columns:1fr 1fr 1fr auto}.tc-row .name{grid-column:1/-1}
.tick{display:flex;flex-wrap:wrap;gap:.5rem;margin:.75rem 0}.tick span{background:#fff;border:1px solid var(--border);border-radius:8px;padding:.4rem .7rem;text-align:center;min-width:64px;font-size:.95rem;color:var(--muted)}
.tick b{display:block;font-size:1.5rem;color:var(--accent-dark);font-variant-numeric:tabular-nums}.tick em{flex-basis:100%;font-style:normal;color:var(--muted);font-size:.95rem}
.span24{position:relative;height:16px;background:#e5e7eb;border-radius:8px;margin:1rem 0 2rem}.span24 i{position:absolute;top:0;bottom:0;background:var(--accent);border-radius:8px}
.span24 span{position:absolute;top:20px;transform:translateX(-50%);font-size:.875rem;color:var(--muted)}.span24 span:first-of-type{transform:none}.span24 span:last-of-type{transform:translateX(-100%)}
.case-out{margin:.6rem 0}.case-h{display:flex;justify-content:space-between;align-items:center;gap:.5rem}
.case-out pre{white-space:pre-wrap;word-break:break-word;background:#fff;border:1px solid var(--border);border-radius:8px;padding:.5rem .7rem;margin:.3rem 0 0;font-family:inherit;font-size:1rem;max-height:9rem;overflow:auto}
.chips{display:flex;flex-wrap:wrap;gap:.4rem;margin:.75rem 0}.chips span{background:var(--accent);color:#fff;border-radius:8px;padding:.35rem .7rem;font-weight:700;font-variant-numeric:tabular-nums}
.picks{font-size:1.2rem;font-weight:700;color:var(--accent-dark)}
.tc-row>*{min-width:0}.tc-row input{width:100%;min-width:0}
@media(max-width:480px){.tc-row{grid-template-columns:1fr 1fr}.tc-row .name{grid-column:1/-1}}