/* ===========================================================
   FitCalc — advanced design system (glass + aurora + motion)
   Class names kept stable so all existing pages upgrade for free.
   =========================================================== */

:root {
  --brand:      #10b981;
  --brand-dark: #059669;
  --brand-2:    #06b6d4;   /* cyan for gradients */
  --brand-soft: #e7f8f1;
  --accent:     #f59e0b;
  --violet:     #6366f1;
  --ink:        #0c1f18;
  --muted:      #5f7168;
  --line:       rgba(16,80,60,.12);
  --bg:         #eef5f2;
  --card:       rgba(255,255,255,.72);
  --ok:         #16a34a;
  --radius:     18px;
  --grad:       linear-gradient(120deg, var(--brand), var(--brand-2));
  --grad-warm:  linear-gradient(120deg, #10b981, #34d399);
  --shadow:     0 10px 30px rgba(12,60,45,.10);
  --shadow-lg:  0 24px 60px rgba(12,60,45,.18);
  --glass-brd:  1px solid rgba(255,255,255,.6);
  --maxw:       1140px;
  --font: -apple-system, BlinkMacSystemFont, "Segoe UI", Roboto, Helvetica, Arial, sans-serif;
  --mono: ui-monospace, "SF Mono", "Segoe UI Mono", Menlo, monospace;
}

* { box-sizing: border-box; margin: 0; padding: 0; }
html { scroll-behavior: smooth; background: var(--bg); }
body { font-family: var(--font); color: var(--ink); background: transparent; line-height: 1.55; -webkit-font-smoothing: antialiased; position: relative; overflow-x: hidden; }
a { color: inherit; text-decoration: none; }
img { max-width: 100%; display: block; }
.wrap { max-width: var(--maxw); margin: 0 auto; padding: 0 20px; }

/* ---------- Animated aurora + grid background ---------- */
body::before {
  content: ""; position: fixed; inset: -25%; z-index: -1; pointer-events: none;
  background:
    radial-gradient(38% 38% at 18% 20%, rgba(16,185,129,.22), transparent 60%),
    radial-gradient(34% 34% at 82% 12%, rgba(52,211,153,.20), transparent 60%),
    radial-gradient(42% 42% at 72% 82%, rgba(6,182,212,.18), transparent 62%);
  filter: blur(20px); animation: drift 20s ease-in-out infinite alternate;
}
body::after {
  content: ""; position: fixed; inset: 0; z-index: -1; pointer-events: none;
  background-image:
    linear-gradient(rgba(16,80,60,.04) 1px, transparent 1px),
    linear-gradient(90deg, rgba(16,80,60,.04) 1px, transparent 1px);
  background-size: 46px 46px;
  -webkit-mask: radial-gradient(120% 80% at 50% -10%, #000 20%, transparent 72%);
          mask: radial-gradient(120% 80% at 50% -10%, #000 20%, transparent 72%);
}
@keyframes drift {
  0%   { transform: translate3d(0,0,0) scale(1); }
  50%  { transform: translate3d(2%, 1.5%, 0) scale(1.06); }
  100% { transform: translate3d(-1.5%, -1%, 0) scale(1.03); }
}

/* ---------- Reveal on scroll ---------- */
.reveal { opacity: 0; transform: translateY(20px); }
.reveal.in { opacity: 1; transform: none; transition: opacity .7s cubic-bezier(.2,.7,.2,1), transform .7s cubic-bezier(.2,.7,.2,1); }
@media (prefers-reduced-motion: reduce) {
  .reveal, .reveal.in { opacity: 1 !important; transform: none !important; transition: none !important; }
  body::before { animation: none !important; }
}

/* ---------- Header ---------- */
.site-header { position: sticky; top: 0; z-index: 50; background: rgba(238,245,242,.7); backdrop-filter: saturate(180%) blur(16px); -webkit-backdrop-filter: saturate(180%) blur(16px); border-bottom: 1px solid var(--line); }
.site-header .wrap { display: flex; align-items: center; justify-content: space-between; height: 68px; }
.logo { display: flex; align-items: center; gap: 10px; font-weight: 800; font-size: 20px; letter-spacing: -.02em; }
.logo .dot { width: 32px; height: 32px; border-radius: 10px; background: var(--grad); display: grid; place-items: center; color: #fff; font-size: 17px; box-shadow: 0 6px 16px rgba(16,185,129,.4); animation: pulse 3.5s ease-in-out infinite; }
@keyframes pulse { 0%,100%{ box-shadow: 0 6px 16px rgba(16,185,129,.4);} 50%{ box-shadow: 0 6px 26px rgba(6,182,212,.55);} }
.logo b { background: var(--grad); -webkit-background-clip: text; background-clip: text; color: transparent; }
.nav-links { display: flex; align-items: center; gap: 24px; }
.nav-links > a { color: var(--muted); font-weight: 600; font-size: 15px; transition: color .15s; }
.nav-links > a:hover { color: var(--ink); }

/* ---------- Category dropdowns ---------- */
.nav-drop { position: relative; }
.nav-drop > .nav-top {
  border: 0; background: none; cursor: pointer; font-family: var(--font);
  color: var(--muted); font-weight: 600; font-size: 15px;
  display: flex; align-items: center; gap: 6px; padding: 22px 0;
  transition: color .15s;
}
.nav-drop:hover > .nav-top, .nav-drop.open > .nav-top { color: var(--ink); }
.nav-drop .caret { font-size: 9px; transition: transform .2s; opacity: .7; }
.nav-drop:hover .caret, .nav-drop.open .caret { transform: rotate(180deg); }
.drop-menu {
  position: absolute; top: 100%; left: 50%; transform: translateX(-50%) translateY(8px);
  min-width: 265px; max-height: 68vh; overflow-y: auto;
  background: rgba(255,255,255,.94); backdrop-filter: blur(16px); -webkit-backdrop-filter: blur(16px);
  border: var(--glass-brd); border-radius: 16px; box-shadow: var(--shadow-lg);
  padding: 8px; z-index: 60;
  opacity: 0; visibility: hidden; pointer-events: none;
  transition: opacity .18s ease, transform .18s ease, visibility .18s;
}
.nav-drop:hover .drop-menu, .nav-drop.open .drop-menu {
  opacity: 1; visibility: visible; pointer-events: auto; transform: translateX(-50%) translateY(0);
}
.drop-menu a {
  display: flex; align-items: center; gap: 11px; padding: 9px 13px; border-radius: 10px;
  font-weight: 600; font-size: 14px; color: var(--ink); white-space: nowrap;
  transition: background .12s, color .12s;
}
.drop-menu a:hover { background: var(--brand-soft); color: var(--brand-dark); }
.drop-menu .dm-ico { font-size: 17px; flex: none; }
.drop-menu .dm-all {
  border-top: 1px solid var(--line); margin-top: 6px; padding-top: 11px;
  justify-content: center; color: var(--brand-dark); font-weight: 700;
}
.btn-nav { background: var(--grad); color: #fff !important; padding: 10px 20px; border-radius: 11px; font-weight: 700; box-shadow: 0 8px 20px rgba(16,185,129,.35); transition: transform .15s, box-shadow .15s; }
.btn-nav:hover { transform: translateY(-2px); box-shadow: 0 12px 26px rgba(16,185,129,.5); }
.menu-toggle { display: none; font-size: 26px; background: none; border: 0; cursor: pointer; color: var(--ink); }

/* ---------- Hero ---------- */
.hero { text-align: center; padding: 84px 0 50px; position: relative; }
.hero h1 { font-size: clamp(32px, 5.4vw, 56px); font-weight: 800; letter-spacing: -.03em; line-height: 1.05; }
.hero h1 span { background: linear-gradient(120deg, var(--brand), var(--brand-2), var(--brand)); background-size: 200% auto; -webkit-background-clip: text; background-clip: text; color: transparent; animation: shine 6s linear infinite; }
@keyframes shine { to { background-position: 200% center; } }
.hero p { color: var(--muted); font-size: 19px; max-width: 640px; margin: 18px auto 0; }
.hero-badge { display: inline-flex; align-items: center; gap: 8px; background: var(--card); border: var(--glass-brd); box-shadow: var(--shadow); padding: 7px 16px; border-radius: 30px; font-size: 13.5px; font-weight: 700; color: var(--brand-dark); margin-bottom: 22px; }
.hero-badge .live { width: 8px; height: 8px; border-radius: 50%; background: var(--brand); box-shadow: 0 0 0 0 rgba(16,185,129,.6); animation: blip 2s infinite; }
@keyframes blip { 0%{ box-shadow: 0 0 0 0 rgba(16,185,129,.5);} 70%{ box-shadow: 0 0 0 8px rgba(16,185,129,0);} 100%{ box-shadow: 0 0 0 0 rgba(16,185,129,0);} }

/* ---------- Card grid ---------- */
.grid { display: grid; gap: 20px; grid-template-columns: repeat(auto-fill, minmax(250px, 1fr)); padding-bottom: 40px; }
.tool-card { position: relative; background: var(--card); border: var(--glass-brd); border-radius: var(--radius); padding: 26px 22px; box-shadow: var(--shadow); backdrop-filter: blur(10px); -webkit-backdrop-filter: blur(10px); transition: transform .22s cubic-bezier(.2,.7,.2,1), box-shadow .22s; display: block; overflow: hidden; }
.tool-card::after { content: ""; position: absolute; inset: 0; border-radius: var(--radius); padding: 1px; background: var(--grad); -webkit-mask: linear-gradient(#000 0 0) content-box, linear-gradient(#000 0 0); -webkit-mask-composite: xor; mask-composite: exclude; opacity: 0; transition: opacity .22s; }
.tool-card:hover { transform: translateY(-6px); box-shadow: var(--shadow-lg); }
.tool-card:hover::after { opacity: 1; }
.tool-ico { width: 54px; height: 54px; border-radius: 15px; display: grid; place-items: center; font-size: 27px; margin-bottom: 15px; background: linear-gradient(135deg, var(--brand-soft), #fff); box-shadow: inset 0 0 0 1px rgba(16,185,129,.15); transition: transform .22s; }
.tool-card:hover .tool-ico { transform: scale(1.08) rotate(-4deg); }
.tool-card h3 { font-size: 18px; margin-bottom: 6px; }
.tool-card p { color: var(--muted); font-size: 14.5px; }

.section-head { text-align: center; margin: 34px 0 28px; }
.section-head h2 { font-size: 30px; letter-spacing: -.02em; }
.section-head p { color: var(--muted); margin-top: 6px; }

/* ---------- Calculator page ---------- */
.tool-hero { text-align: center; padding: 50px 0 28px; }
.tool-hero .tool-ico { margin: 0 auto 18px; width: 68px; height: 68px; font-size: 34px; }
.tool-hero h1 { font-size: clamp(28px, 4.2vw, 40px); letter-spacing: -.02em; }
.tool-hero p { color: var(--muted); font-size: 17px; max-width: 590px; margin: 12px auto 0; }

.calc-layout { display: grid; grid-template-columns: 1fr 1fr; gap: 24px; margin-bottom: 30px; }
.panel { background: var(--card); border: var(--glass-brd); border-radius: var(--radius); box-shadow: var(--shadow); backdrop-filter: blur(14px); -webkit-backdrop-filter: blur(14px); padding: 28px; }
.panel h2 { font-size: 19px; margin-bottom: 18px; letter-spacing: -.01em; }

/* Form */
.form-row { margin-bottom: 16px; }
.form-row > label { display: block; font-size: 13px; font-weight: 700; color: var(--muted); margin-bottom: 6px; }
input[type=number], input[type=text], input[type=date], select {
  width: 100%; padding: 12px 14px; border: 1px solid var(--line); border-radius: 12px; font-size: 16px;
  font-family: var(--font); background: rgba(255,255,255,.75); color: var(--ink); transition: border-color .15s, box-shadow .15s;
}
input:focus, select:focus { outline: none; border-color: var(--brand); box-shadow: 0 0 0 4px rgba(16,185,129,.16); }
.inline { display: flex; gap: 10px; }
.inline > * { flex: 1; }

/* Segmented toggle */
.seg { display: inline-flex; background: rgba(16,185,129,.1); border-radius: 12px; padding: 5px; gap: 4px; flex-wrap: wrap; }
.seg button { border: 0; background: none; cursor: pointer; font-family: var(--font); font-weight: 700; font-size: 14px; color: var(--muted); padding: 9px 18px; border-radius: 8px; transition: color .2s, background .2s, box-shadow .2s, transform .1s; }
.seg button.on { background: #fff; color: var(--brand-dark); box-shadow: 0 3px 10px rgba(12,60,45,.14); }
.seg button:active { transform: scale(.96); }

input[type=range] { accent-color: var(--brand); width: 100%; padding: 0; }

/* Result */
.result-big { text-align: center; padding: 10px 0 4px; }
.result-big .num { font-size: 58px; font-weight: 800; line-height: 1; font-variant-numeric: tabular-nums; letter-spacing: -.02em;
  background: var(--grad); -webkit-background-clip: text; background-clip: text; color: transparent; }
.result-big .unit { font-size: 18px; color: var(--muted); font-weight: 700; }
.result-big .label { color: var(--muted); font-size: 15px; margin-top: 10px; }

.result-rows { margin-top: 22px; }
.rrow { display: flex; justify-content: space-between; align-items: center; padding: 13px 0; border-top: 1px solid var(--line); }
.rrow .k { color: var(--muted); font-weight: 600; font-size: 14.5px; }
.rrow .v { font-weight: 800; font-size: 17px; font-variant-numeric: tabular-nums; }

.pill { display: inline-block; padding: 5px 14px; border-radius: 20px; font-weight: 700; font-size: 14px; }
.pill.good { background: #dcfce7; color: #15803d; }
.pill.warn { background: #fef3c7; color: #b45309; }
.pill.bad  { background: #fee2e2; color: #b91c1c; }

/* Macro / segmented bars */
.bar { height: 15px; border-radius: 9px; background: rgba(16,80,60,.1); overflow: hidden; display: flex; margin: 12px 0 6px; }
.bar span { height: 100%; transition: width .6s cubic-bezier(.2,.7,.2,1); }
.macro-legend { display: flex; gap: 16px; flex-wrap: wrap; font-size: 13px; color: var(--muted); }
.macro-legend i { width: 11px; height: 11px; border-radius: 3px; display: inline-block; margin-right: 5px; }

/* Gauge (semicircle) */
.gauge-wrap { text-align: center; margin: 6px auto 4px; }
.gauge { width: 260px; max-width: 100%; }
.gauge .track { fill: none; stroke: rgba(16,80,60,.1); stroke-width: 16; stroke-linecap: round; }
.gauge .fill  { fill: none; stroke-width: 16; stroke-linecap: round; transition: stroke-dashoffset .8s cubic-bezier(.2,.7,.2,1), stroke .4s; }
.gauge .needle { transition: transform .8s cubic-bezier(.34,1.4,.5,1); transform-origin: 130px 130px; transform-box: view-box; }

/* Ring (full circle progress) */
.ring-wrap { display: grid; place-items: center; position: relative; }
.ring { transform: rotate(-90deg); }
.ring .track { fill: none; stroke: rgba(16,80,60,.1); stroke-width: 14; }
.ring .fill { fill: none; stroke: url(#rg); stroke-width: 14; stroke-linecap: round; transition: stroke-dashoffset .9s cubic-bezier(.2,.7,.2,1); }
.ring-label { position: absolute; text-align: center; }
.ring-label .rv { font-size: 34px; font-weight: 800; font-variant-numeric: tabular-nums; background: var(--grad); -webkit-background-clip: text; background-clip: text; color: transparent; }
.ring-label .rk { font-size: 12px; color: var(--muted); font-weight: 700; }

/* Heart-rate zone bars */
.zones { display: flex; flex-direction: column; gap: 10px; margin-top: 6px; }
.zone { display: grid; grid-template-columns: 42px 1fr auto; align-items: center; gap: 12px; }
.zone .zbadge { width: 42px; height: 42px; border-radius: 12px; display: grid; place-items: center; color: #fff; font-weight: 800; font-size: 15px; }
.zone .ztrack { height: 12px; border-radius: 8px; background: rgba(16,80,60,.08); overflow: hidden; }
.zone .zfill { height: 100%; border-radius: 8px; width: 0; transition: width .8s cubic-bezier(.2,.7,.2,1); }
.zone .zmeta b { display: block; font-size: 15px; font-variant-numeric: tabular-nums; }
.zone .zmeta span { font-size: 12px; color: var(--muted); }

/* Rep table (1RM) */
.rep-table { width: 100%; border-collapse: collapse; margin-top: 8px; font-variant-numeric: tabular-nums; }
.rep-table th, .rep-table td { padding: 10px 8px; text-align: center; border-bottom: 1px solid var(--line); font-size: 14.5px; }
.rep-table th { color: var(--muted); font-size: 12px; text-transform: uppercase; letter-spacing: .05em; }
.rep-table td:first-child { font-weight: 800; color: var(--brand-dark); }
.rep-table tr:hover td { background: rgba(16,185,129,.06); }

.metric-chips { display: flex; gap: 10px; flex-wrap: wrap; margin-top: 4px; }
.chip { background: rgba(16,185,129,.1); color: var(--brand-dark); font-weight: 700; font-size: 13px; padding: 8px 14px; border-radius: 30px; font-variant-numeric: tabular-nums; }

.note { color: var(--muted); font-size: 13.5px; margin-top: 18px; line-height: 1.55; }

/* Article / SEO */
.article { max-width: 760px; margin: 12px auto 54px; }
.article h2 { font-size: 25px; margin: 32px 0 12px; letter-spacing: -.01em; }
.article h3 { font-size: 19px; margin: 22px 0 8px; }
.article p { color: #2c3d37; margin-bottom: 12px; }
.article ul { margin: 0 0 14px 22px; color: #2c3d37; }
.article li { margin-bottom: 6px; }
.faq { border-top: 1px solid var(--line); padding: 16px 0; }
.faq h3 { margin: 0 0 6px; font-size: 17px; }
.faq p { margin: 0; color: var(--muted); }

/* Feature strip */
.features { display: grid; grid-template-columns: repeat(auto-fit, minmax(230px,1fr)); gap: 22px; padding: 20px 0 64px; }
.feature { text-align: center; padding: 22px 14px; background: var(--card); border: var(--glass-brd); border-radius: var(--radius); box-shadow: var(--shadow); backdrop-filter: blur(8px); -webkit-backdrop-filter: blur(8px); transition: transform .2s; }
.feature:hover { transform: translateY(-4px); }
.feature .fico { font-size: 32px; }
.feature h4 { margin: 10px 0 4px; }
.feature p { color: var(--muted); font-size: 14.5px; }

/* Footer */
.site-footer { background: #08150f; color: #b9ccc4; padding: 54px 0 30px; margin-top: 40px; position: relative; }
.footer-grid { display: grid; grid-template-columns: 1.4fr repeat(3, 1fr); gap: 30px; }
.footer-grid h5 { color: #fff; font-size: 15px; margin-bottom: 14px; }
.footer-grid a { display: block; color: #8ba79b; font-size: 14px; padding: 4px 0; transition: color .15s; }
.footer-grid a:hover { color: var(--brand); }
.footer-brand p { color: #8ba79b; font-size: 14px; margin-top: 12px; max-width: 260px; }
.footer-bottom { border-top: 1px solid #1b2f27; margin-top: 32px; padding-top: 20px; text-align: center; color: #6f887e; font-size: 13px; line-height: 1.6; }

.back { display: inline-flex; align-items: center; gap: 6px; color: var(--muted); font-weight: 600; margin: 6px 0 0; transition: color .15s, gap .15s; }
.back:hover { color: var(--brand); gap: 10px; }
.hidden { display: none !important; }

/* ---------- Search (homepage) ---------- */
.search-wrap { max-width: 560px; margin: 26px auto 0; position: relative; }
.search-wrap input {
  width: 100%; padding: 15px 20px 15px 50px; border-radius: 16px; border: var(--glass-brd);
  background: var(--card); box-shadow: var(--shadow); font-size: 16.5px; font-family: var(--font);
  backdrop-filter: blur(10px); -webkit-backdrop-filter: blur(10px); color: var(--ink);
}
.search-wrap input:focus { outline: none; box-shadow: var(--shadow-lg), 0 0 0 4px rgba(16,185,129,.18); }
.search-wrap .sicon { position: absolute; left: 18px; top: 50%; transform: translateY(-50%); font-size: 18px; opacity: .55; pointer-events: none; }
.search-empty { text-align: center; color: var(--muted); padding: 30px 0 10px; font-weight: 600; display: none; }

/* ---------- Breadcrumbs ---------- */
.crumbs { display: flex; align-items: center; gap: 8px; font-size: 13.5px; color: var(--muted); padding: 18px 0 0; flex-wrap: wrap; }
.crumbs a { color: var(--muted); font-weight: 600; }
.crumbs a:hover { color: var(--brand); }
.crumbs .sep { opacity: .5; }
.crumbs .here { color: var(--ink); font-weight: 700; }

/* ---------- Spectrum scale (where you fall) ---------- */
.spectrum { margin: 20px 0 6px; }
.spectrum .strack { position: relative; height: 16px; border-radius: 10px; display: flex; overflow: visible; }
.spectrum .sseg { height: 100%; position: relative; }
.spectrum .sseg:first-child { border-radius: 10px 0 0 10px; }
.spectrum .sseg:last-child { border-radius: 0 10px 10px 0; }
.spectrum .smarker {
  position: absolute; top: 50%; width: 26px; height: 26px; border-radius: 50%;
  background: #fff; border: 4px solid var(--ink); transform: translate(-50%, -50%);
  box-shadow: 0 4px 12px rgba(12,60,45,.3); z-index: 2;
  transition: left .8s cubic-bezier(.34,1.3,.5,1), border-color .4s;
}
.spectrum .slabels { display: flex; margin-top: 10px; }
.spectrum .slabel { font-size: 11.5px; color: var(--muted); font-weight: 700; text-align: center; line-height: 1.3; }
.spectrum .slabel small { display: block; font-weight: 600; opacity: .8; }

/* ---------- Reference table ---------- */
.ref-table { width: 100%; border-collapse: collapse; margin: 10px 0 6px; font-size: 14.5px; }
.ref-table th, .ref-table td { padding: 11px 12px; text-align: left; border-bottom: 1px solid var(--line); }
.ref-table th { color: var(--muted); font-size: 12px; text-transform: uppercase; letter-spacing: .05em; }
.ref-table tr.hl td { background: rgba(16,185,129,.12); font-weight: 700; border-radius: 8px; }
.ref-table td .dot-c { display: inline-block; width: 10px; height: 10px; border-radius: 50%; margin-right: 8px; }

/* ---------- Formula compare cards ---------- */
.formula-grid { display: grid; grid-template-columns: repeat(auto-fit, minmax(150px, 1fr)); gap: 12px; margin: 14px 0 4px; }
.fcard { background: rgba(255,255,255,.6); border: 1px solid var(--line); border-radius: 14px; padding: 14px; text-align: center; transition: transform .18s, box-shadow .18s; }
.fcard:hover { transform: translateY(-3px); box-shadow: var(--shadow); }
.fcard .fv { font-size: 22px; font-weight: 800; font-variant-numeric: tabular-nums; background: var(--grad); -webkit-background-clip: text; background-clip: text; color: transparent; }
.fcard .fk { font-size: 12px; color: var(--muted); font-weight: 700; margin-top: 3px; }
.fcard.best { border-color: var(--brand); box-shadow: 0 0 0 1px var(--brand), var(--shadow); position: relative; }
.fcard.best::after { content: "recommended"; position: absolute; top: -9px; left: 50%; transform: translateX(-50%); background: var(--grad); color: #fff; font-size: 9.5px; font-weight: 800; letter-spacing: .05em; text-transform: uppercase; padding: 2px 10px; border-radius: 12px; white-space: nowrap; }

/* ---------- Result actions (copy/share) ---------- */
.result-actions { display: flex; gap: 10px; justify-content: center; margin-top: 18px; flex-wrap: wrap; }
.mini-btn {
  border: 1px solid var(--line); background: rgba(255,255,255,.7); color: var(--ink);
  font-family: var(--font); font-weight: 700; font-size: 13px; padding: 9px 16px; border-radius: 10px;
  cursor: pointer; display: inline-flex; align-items: center; gap: 7px; transition: border-color .15s, transform .1s, background .15s;
}
.mini-btn:hover { border-color: var(--brand); background: #fff; }
.mini-btn:active { transform: scale(.96); }

/* ---------- Related calculators strip ---------- */
.related { margin: 10px 0 40px; }
.related h2 { font-size: 21px; margin-bottom: 16px; text-align: center; }
.related .rgrid { display: grid; grid-template-columns: repeat(auto-fill, minmax(200px, 1fr)); gap: 14px; }
.related .rcard {
  display: flex; align-items: center; gap: 12px; background: var(--card); border: var(--glass-brd);
  border-radius: 14px; padding: 14px 16px; box-shadow: var(--shadow); font-weight: 700; font-size: 14.5px;
  transition: transform .18s, box-shadow .18s; backdrop-filter: blur(8px); -webkit-backdrop-filter: blur(8px);
}
.related .rcard:hover { transform: translateY(-3px); box-shadow: var(--shadow-lg); color: var(--brand-dark); }
.related .rcard .ri { font-size: 22px; flex: none; }

/* Toast */
.toast {
  position: fixed; bottom: 24px; left: 50%; transform: translateX(-50%);
  background: var(--ink); color: #fff; padding: 12px 20px; border-radius: 10px;
  font-weight: 600; font-size: 14px; box-shadow: var(--shadow-lg); z-index: 200; opacity: 0;
  transition: opacity .2s, transform .2s; pointer-events: none;
}
.toast.show { opacity: 1; transform: translateX(-50%) translateY(-4px); }

@media (max-width: 820px) { .calc-layout { grid-template-columns: 1fr; } }
@media (max-width: 780px) {
  .nav-links {
    display: none; position: absolute; top: 68px; left: 0; right: 0;
    flex-direction: column; align-items: stretch; gap: 2px;
    background: rgba(255,255,255,.97); backdrop-filter: blur(16px); -webkit-backdrop-filter: blur(16px);
    padding: 12px 18px 18px; border-bottom: 1px solid var(--line); box-shadow: var(--shadow-lg);
    max-height: calc(100vh - 68px); overflow-y: auto;
  }
  .nav-links.open { display: flex; }
  .nav-links > a, .nav-drop > .nav-top { padding: 12px 6px; width: 100%; justify-content: space-between; font-size: 16px; }
  .menu-toggle { display: block; }
  /* dropdowns become accordions */
  .drop-menu {
    position: static; transform: none; min-width: 0; max-height: none;
    background: transparent; border: 0; box-shadow: none; border-radius: 0;
    padding: 0 0 6px 14px; display: none;
    opacity: 1; visibility: visible; pointer-events: auto; transition: none;
  }
  .nav-drop:hover .drop-menu { display: none; }        /* hover doesn't apply on touch */
  .nav-drop.open .drop-menu { display: block; transform: none; }
  .drop-menu a { white-space: normal; }
  .btn-nav { text-align: center; margin-top: 8px; }
  .footer-grid { grid-template-columns: 1fr 1fr; }
  .footer-brand { grid-column: 1 / -1; }
}

/* ===========================================================
   PRO FEATURES LAYER (dark mode, share, charts, embed, tracker)
   =========================================================== */

/* ---------- Dark theme ---------- */
html[data-theme="dark"] {
  --ink:#e6f0eb; --muted:#8fa79c; --line:rgba(255,255,255,.09);
  --bg:#0b1512; --card:rgba(22,34,29,.72); --brand-soft:rgba(16,185,129,.14);
  --glass-brd:1px solid rgba(255,255,255,.08);
  --shadow:0 10px 30px rgba(0,0,0,.35); --shadow-lg:0 24px 60px rgba(0,0,0,.5);
}
html[data-theme="dark"] body::after {
  background-image:
    linear-gradient(rgba(255,255,255,.035) 1px, transparent 1px),
    linear-gradient(90deg, rgba(255,255,255,.035) 1px, transparent 1px);
}
html[data-theme="dark"] .site-header { background: rgba(11,21,18,.72); }
html[data-theme="dark"] input[type=number], html[data-theme="dark"] input[type=text],
html[data-theme="dark"] input[type=date], html[data-theme="dark"] select, html[data-theme="dark"] textarea {
  background: rgba(255,255,255,.06); color: var(--ink); border-color: var(--line);
}
html[data-theme="dark"] select option { background:#14201b; color:var(--ink); }
html[data-theme="dark"] .seg button.on { background:#1d332a; color:#4ade80; }
html[data-theme="dark"] .fcard { background: rgba(255,255,255,.05); }
html[data-theme="dark"] .mini-btn { background: rgba(255,255,255,.06); color: var(--ink); }
html[data-theme="dark"] .mini-btn:hover { background: rgba(255,255,255,.12); }
html[data-theme="dark"] .drop-menu { background: rgba(16,27,23,.96); }
html[data-theme="dark"] .article p, html[data-theme="dark"] .article ul { color:#b9cdc4; }
html[data-theme="dark"] .bar, html[data-theme="dark"] .zone .ztrack { background: rgba(255,255,255,.1); }
html[data-theme="dark"] .gauge .track { stroke: rgba(255,255,255,.1); }
html[data-theme="dark"] .ring .track { stroke: rgba(255,255,255,.1); }
html[data-theme="dark"] .spectrum .smarker { background:#0b1512; }
html[data-theme="dark"] .toast { background:#e6f0eb; color:#0b1512; }
html[data-theme="dark"] .rep-table tr:hover td { background: rgba(16,185,129,.1); }
@media (max-width: 780px) { html[data-theme="dark"] .nav-links { background: rgba(11,21,18,.97); } }

/* Header action buttons (theme / install) */
.hdr-actions { display:flex; align-items:center; gap:10px; }
.icon-btn {
  border:1px solid var(--line); background:var(--card); cursor:pointer; font-family:var(--font);
  font-size:15px; font-weight:700; color:var(--ink); border-radius:10px; padding:8px 12px;
  transition: transform .12s, border-color .15s;
}
.icon-btn:hover { border-color: var(--brand); }
.icon-btn:active { transform: scale(.94); }

/* ---------- Share bar ---------- */
.share-bar { border-top:1px solid var(--line); margin-top:20px; padding-top:16px; }

/* ---------- Insight box ---------- */
.insight {
  margin-top:18px; padding:15px 17px; border-radius:13px; font-size:14.5px; line-height:1.6;
  background: linear-gradient(120deg, rgba(16,185,129,.1), rgba(6,182,212,.08));
  border-left: 4px solid var(--brand); color: var(--ink);
}
.insight b { color: var(--brand-dark); }
html[data-theme="dark"] .insight b { color:#4ade80; }
.insight .ins-title { font-weight:800; font-size:13px; text-transform:uppercase; letter-spacing:.05em; color:var(--brand-dark); margin-bottom:5px; display:flex; align-items:center; gap:6px; }
html[data-theme="dark"] .insight .ins-title { color:#4ade80; }

/* ---------- Charts ---------- */
.chart-box { margin-top:14px; }
.chart-box canvas { width:100%; display:block; }

/* ---------- Modal (embed code) ---------- */
.modal-overlay {
  position:fixed; inset:0; background:rgba(8,15,12,.55); backdrop-filter: blur(4px);
  z-index:300; display:grid; place-items:center; padding:20px;
}
.modal {
  background:var(--card); backdrop-filter: blur(20px); -webkit-backdrop-filter: blur(20px);
  border:var(--glass-brd); border-radius:18px; box-shadow:var(--shadow-lg);
  max-width:560px; width:100%; padding:24px;
}
.modal h3 { margin-bottom:8px; }
.modal p { color:var(--muted); font-size:14px; margin-bottom:12px; }
.modal textarea {
  width:100%; border:1px solid var(--line); border-radius:11px; padding:12px;
  font-family:var(--mono); font-size:12.5px; background:rgba(128,128,128,.08); color:var(--ink);
  resize:vertical; min-height:110px;
}
.modal .btn-row { display:flex; gap:10px; margin-top:14px; justify-content:flex-end; }

/* ---------- Recently used (homepage) ---------- */
.recent-strip { margin: 0 0 10px; }
.recent-strip .section-head { margin: 6px 0 16px; }

/* ---------- Embed mode ---------- */
html.embed .site-header, html.embed .crumbs, html.embed .related,
html.embed .article, html.embed .back, html.embed #site-footer,
html.embed .tool-hero p, html.embed .share-bar { display:none !important; }
html.embed .tool-hero { padding:16px 0 8px; }
html.embed .tool-hero .tool-ico { width:46px; height:46px; font-size:24px; margin-bottom:8px; }
html.embed .tool-hero h1 { font-size:24px; }
.embed-credit {
  display:block; text-align:center; padding:8px 0 18px; font-size:12.5px;
  color:var(--muted); font-weight:600;
}
.embed-credit:hover { color: var(--brand); }

/* ---------- Tracker ---------- */
.track-entries { max-height: 300px; overflow-y:auto; }
.track-entries .rrow .del {
  border:0; background:none; cursor:pointer; font-size:15px; color:var(--muted); padding:4px 8px; border-radius:8px;
}
.track-entries .rrow .del:hover { color:#ef4444; background:rgba(239,68,68,.1); }