/* ============================================================
   Quick Percentage Calculator — shared styles
   Modern, responsive, light + dark theme
   ============================================================ */

/* ---------- Theme tokens ---------- */
:root{
  color-scheme: light;
  --bg:#f7f6f3;
  --bg-grad-1:rgba(109,93,252,.14);
  --bg-grad-2:rgba(255,184,77,.16);
  --bg-grad-3:rgba(255,255,255,1);
  --surface:#ffffff;
  --surface-2:#f2eee8;
  --surface-3:#ebe6df;
  --ink:#1a1a20;
  --ink-2:#3a3a44;
  --muted:#6a6a76;
  --line:#e4ddd5;
  --line-2:#d4ccc1;
  --brand:#6d5dfc;
  --brand-2:#8a63ff;
  --brand-3:#ffb84d;
  --brand-soft:rgba(109,93,252,.10);
  --brand-ring:rgba(109,93,252,.16);
  --green:#168a62;
  --green-soft:rgba(22,138,98,.10);
  --red:#c2413a;
  --red-soft:rgba(194,65,58,.10);
  --blue:#316bff;
  --shadow:0 20px 60px rgba(26,26,32,.10);
  --soft-shadow:0 8px 28px rgba(26,26,32,.07);
  --hover-lift:0 14px 40px rgba(26,26,32,.12);
  --radius:22px;
  --radius-sm:14px;
  --radius-xs:10px;
  --max:1680px;
  --gutter:clamp(1rem,2.2vw,2.25rem);
  --t:220ms cubic-bezier(.4,0,.2,1);
  --header-h:64px;
}

[data-theme="dark"]{
  color-scheme:dark;
  --bg:#0d0d12;
  --bg-grad-1:rgba(109,93,252,.20);
  --bg-grad-2:rgba(255,184,77,.08);
  --bg-grad-3:rgba(24,24,32,1);
  --surface:#181820;
  --surface-2:#22222c;
  --surface-3:#2a2a36;
  --ink:#f2f2f7;
  --ink-2:#d4d4de;
  --muted:#9a9aa8;
  --line:#2e2e3a;
  --line-2:#3a3a48;
  --brand:#8b7fff;
  --brand-2:#a78bff;
  --brand-3:#ffc970;
  --brand-soft:rgba(139,127,255,.14);
  --brand-ring:rgba(139,127,255,.20);
  --green:#34d399;
  --green-soft:rgba(52,211,153,.12);
  --red:#f87171;
  --red-soft:rgba(248,113,113,.12);
  --blue:#60a5fa;
  --shadow:0 20px 60px rgba(0,0,0,.45);
  --soft-shadow:0 8px 28px rgba(0,0,0,.35);
  --hover-lift:0 14px 44px rgba(0,0,0,.50);
}

/* ---------- Reset ---------- */
*,*::before,*::after{box-sizing:border-box}
html{scroll-behavior:smooth;-webkit-text-size-adjust:100%}
body{
  margin:0;
  font-family:Inter,ui-sans-serif,system-ui,-apple-system,BlinkMacSystemFont,"Segoe UI",Roboto,sans-serif;
  color:var(--ink);
  background:
    radial-gradient(circle at 0% 0%,var(--bg-grad-1),transparent 32rem),
    radial-gradient(circle at 100% 0%,var(--bg-grad-2),transparent 30rem),
    linear-gradient(180deg,var(--bg-grad-3) 0%,var(--bg) 50%,var(--surface) 100%);
  background-attachment:fixed;
  line-height:1.6;
  -webkit-font-smoothing:antialiased;
  text-rendering:optimizeLegibility;
  overflow-x:hidden;
}
a{color:inherit;text-decoration:none}
a:hover{text-decoration:underline}
button,input,select,textarea{font:inherit;color:inherit}
h1,h2,h3,h4{text-wrap:balance}
img{max-width:100%}

/* ---------- Skip link ---------- */
.skip-link{
  position:absolute;left:-999px;top:auto;width:1px;height:1px;overflow:hidden;
}
.skip-link:focus{
  left:1rem;top:1rem;width:auto;height:auto;
  background:var(--surface);color:var(--ink);
  padding:.7rem 1.1rem;border-radius:12px;z-index:1000;
  box-shadow:var(--shadow);border:1px solid var(--line);
}

/* ---------- Header / nav ---------- */
.site-header{
  position:sticky;top:0;z-index:100;
  backdrop-filter:saturate(180%) blur(18px);
  -webkit-backdrop-filter:saturate(180%) blur(18px);
  background:color-mix(in srgb,var(--surface) 78%,transparent);
  border-bottom:1px solid var(--line);
  transition:background var(--t),border-color var(--t);
}
.nav-wrap{
  width:min(100%,var(--max));margin:auto;
  display:flex;align-items:center;justify-content:space-between;
  gap:clamp(.6rem,1.5vw,1.5rem);
  padding:.6rem var(--gutter);
  min-height:var(--header-h);
}
.logo{
  display:flex;align-items:center;gap:.6rem;
  font-weight:800;letter-spacing:-.03em;
  white-space:nowrap;flex:none;font-size:1.02rem;
}
.logo:hover{text-decoration:none}
.logo-mark{
  width:34px;height:34px;border-radius:11px;
  background:linear-gradient(135deg,var(--brand),var(--brand-2));
  display:grid;place-items:center;color:#fff;
  box-shadow:var(--soft-shadow);
  font-size:1.15rem;font-weight:900;
  transition:transform var(--t);
}
.logo:hover .logo-mark{transform:rotate(-8deg) scale(1.05)}

.nav-links{
  display:flex;align-items:center;justify-content:flex-end;
  gap:.15rem;flex:1;min-width:0;white-space:nowrap;
}
.nav-links > a,.nav-more-toggle,.nav-cta{
  padding:.5rem clamp(.5rem,.85vw,.78rem);border-radius:11px;
  color:var(--ink-2);font-size:.9rem;font-weight:600;flex:none;
  transition:background var(--t),color var(--t);
}
.nav-links a:hover,.nav-more-toggle:hover,.nav-cta:hover{
  background:var(--brand-soft);text-decoration:none;color:var(--brand);
}
.nav-cta{
  background:var(--ink);color:#fff!important;
  box-shadow:var(--soft-shadow);
}
[data-theme="dark"] .nav-cta{background:var(--brand);color:#fff!important}
.nav-cta:hover{background:var(--brand);color:#fff!important}

.nav-more{position:relative;display:none;flex:none}
.nav-more.has-items{display:block}
.nav-more-toggle{
  display:flex;align-items:center;gap:.35rem;
  border:0;background:transparent;cursor:pointer;
}
.nav-more-toggle::after{
  content:"";width:.42rem;height:.42rem;
  border-right:2px solid currentColor;border-bottom:2px solid currentColor;
  transform:rotate(45deg) translateY(-2px);
}
.nav-more-menu{
  position:absolute;right:0;top:calc(100% + .45rem);z-index:120;
  display:none;min-width:230px;padding:.45rem;
  border:1px solid var(--line);border-radius:16px;
  background:var(--surface);box-shadow:var(--shadow);
  white-space:normal;
}
.nav-more.open .nav-more-menu{display:grid;animation:fadeInUp .18s ease}
.nav-more-menu a{
  padding:.68rem .75rem;border-radius:11px;
  color:var(--ink-2);font-size:.91rem;font-weight:600;
}
.nav-more-menu a:hover{background:var(--surface-2);text-decoration:none}
.nav-more-menu .nav-cta{background:transparent;color:var(--ink-2)!important;box-shadow:none}

.mobile-toggle{
  display:none;border:1px solid var(--line);
  background:var(--surface);border-radius:12px;
  padding:.5rem .7rem;cursor:pointer;font-size:1.1rem;line-height:1;
  color:var(--ink);
}

/* Theme toggle */
.theme-toggle{
  display:inline-flex;align-items:center;justify-content:center;
  width:38px;height:38px;flex:none;
  border:1px solid var(--line);background:var(--surface);
  border-radius:11px;cursor:pointer;color:var(--ink);
  transition:background var(--t),border-color var(--t),transform var(--t);
}
.theme-toggle:hover{background:var(--brand-soft);border-color:var(--brand);transform:rotate(15deg)}
.theme-toggle:active{transform:scale(.92)}
.theme-toggle svg{width:18px;height:18px}
.theme-toggle .icon-moon{display:none}
[data-theme="dark"] .theme-toggle .icon-sun{display:none}
[data-theme="dark"] .theme-toggle .icon-moon{display:block}

/* ---------- Layout ---------- */
main{min-height:65vh}
.container{width:min(100%,var(--max));margin:0 auto;padding:0 var(--gutter)}

/* ---------- Hero ---------- */
.hero{padding:clamp(2rem,4vw,3rem) 0 1.5rem}
.hero-grid{
  display:grid;
  grid-template-columns:minmax(0,1.08fr) minmax(380px,.92fr);
  gap:clamp(1.5rem,4vw,4.5rem);align-items:center;
}
.hero-grid > .panel{width:100%}
.eyebrow{
  display:inline-flex;align-items:center;gap:.45rem;
  border:1px solid var(--line);background:color-mix(in srgb,var(--surface) 75%,transparent);
  border-radius:999px;padding:.42rem .8rem;
  font-size:.86rem;font-weight:600;color:var(--ink-2);
  box-shadow:0 6px 22px rgba(31,31,37,.04);
}
.eyebrow::before{
  content:"";width:.55rem;height:.55rem;
  background:var(--green);border-radius:99px;
  box-shadow:0 0 0 3px var(--green-soft);
}

h1,h2,h3{line-height:1.08;letter-spacing:-.04em;margin:0 0 1rem}
h1{font-size:clamp(2.3rem,4.5vw,4.2rem);font-weight:900}
h2{font-size:clamp(1.65rem,3vw,2.5rem);font-weight:800}
h3{font-size:clamp(1.15rem,1.6vw,1.35rem);font-weight:800}
.lede{
  font-size:clamp(1.02rem,1.4vw,1.2rem);
  color:var(--muted);max-width:68ch;margin:0 0 1.25rem;
}
.hero-actions{display:flex;gap:.75rem;flex-wrap:wrap;margin:1.25rem 0}
.stats{display:flex;flex-wrap:wrap;gap:.5rem;margin-top:1rem}
.stat-pill{
  padding:.4rem .7rem;border:1px solid var(--line);
  border-radius:999px;background:color-mix(in srgb,var(--surface) 70%,transparent);
  color:var(--ink-2);font-size:.83rem;font-weight:600;
}

/* ---------- Buttons ---------- */
.btn{
  display:inline-flex;align-items:center;justify-content:center;gap:.5rem;
  padding:.82rem 1.15rem;border-radius:13px;
  border:1px solid var(--line);background:var(--surface);
  box-shadow:0 6px 20px rgba(31,31,37,.05);
  font-weight:700;font-size:.95rem;cursor:pointer;
  transition:transform var(--t),box-shadow var(--t),background var(--t),border-color var(--t);
  -webkit-tap-highlight-color:transparent;
}
.btn:hover{text-decoration:none;transform:translateY(-2px);box-shadow:var(--hover-lift)}
.btn:active{transform:translateY(0) scale(.98)}
.btn-primary{background:var(--ink);color:#fff;border-color:var(--ink)}
[data-theme="dark"] .btn-primary{background:var(--brand);border-color:var(--brand)}
.btn-brand{
  background:linear-gradient(135deg,var(--brand),var(--brand-2));
  color:#fff;border-color:transparent;
  box-shadow:0 8px 24px var(--brand-ring);
}
.btn-brand:hover{box-shadow:0 12px 32px var(--brand-ring)}
.btn-ghost{background:color-mix(in srgb,var(--surface) 60%,transparent)}
.btn:focus-visible{outline:3px solid var(--brand-ring);outline-offset:2px}

/* ---------- Panels / cards ---------- */
.panel{
  background:color-mix(in srgb,var(--surface) 88%,transparent);
  border:1px solid var(--line);
  border-radius:var(--radius);
  box-shadow:var(--shadow);
}
.calculator-card{padding:clamp(1.1rem,2vw,1.5rem)}
.card-head{display:flex;align-items:flex-start;justify-content:space-between;gap:1rem;margin-bottom:1.1rem}
.card-title{font-weight:800;font-size:1.12rem;letter-spacing:-.02em}
.card-sub{font-size:.9rem;color:var(--muted);margin-top:.15rem}
.badge{
  display:inline-flex;align-items:center;gap:.3rem;
  border-radius:999px;padding:.3rem .6rem;
  background:var(--green-soft);color:var(--green);
  font-weight:800;font-size:.74rem;letter-spacing:.04em;text-transform:uppercase;
  flex:none;
}
.badge::before{content:"";width:.4rem;height:.4rem;background:var(--green);border-radius:99px;animation:pulse 2s ease-in-out infinite}

/* ---------- Mode tabs ---------- */
.mode-tabs{
  display:grid;grid-template-columns:repeat(2,minmax(0,1fr));
  gap:.45rem;margin-bottom:1.1rem;
}
.mode-tab{
  border:1px solid var(--line);background:var(--surface-2);
  border-radius:12px;padding:.6rem .65rem;
  font-size:.85rem;font-weight:600;text-align:left;cursor:pointer;
  color:var(--ink-2);
  transition:all var(--t);
  -webkit-tap-highlight-color:transparent;
}
.mode-tab:hover{background:var(--surface);border-color:var(--line-2)}
.mode-tab.active{
  background:var(--surface);
  border-color:var(--brand);
  box-shadow:0 0 0 3px var(--brand-ring);
  color:var(--brand);
}
.mode-panel{animation:fadeInUp .3s ease}

/* ---------- Forms ---------- */
.form-grid{display:grid;grid-template-columns:1fr 1fr;gap:.85rem}
.form-grid.three{grid-template-columns:1fr 1fr 1fr}
.field{display:flex;flex-direction:column;gap:.35rem;margin-bottom:.6rem}
.field.full{grid-column:1/-1}
label{font-weight:700;font-size:.87rem;color:var(--ink-2)}
.hint{font-size:.8rem;color:var(--muted)}

input,select,textarea{
  width:100%;border:1px solid var(--line);border-radius:13px;
  background:var(--surface);padding:.8rem .9rem;
  color:var(--ink);outline:none;
  font-variant-numeric:tabular-nums;
  transition:border-color var(--t),box-shadow var(--t),background var(--t);
}
textarea{resize:vertical;min-height:7rem}
input::placeholder,textarea::placeholder{color:var(--muted);opacity:.6}
input:hover,select:hover,textarea:hover{border-color:var(--line-2)}
input:focus,select:focus,textarea:focus{
  border-color:var(--brand);
  box-shadow:0 0 0 4px var(--brand-ring);
}
select{
  appearance:none;-webkit-appearance:none;
  background-image:url("data:image/svg+xml,%3Csvg xmlns='http://www.w3.org/2000/svg' width='12' height='12' viewBox='0 0 12 12'%3E%3Cpath d='M2 4l4 4 4-4' stroke='%236a6a76' stroke-width='1.6' fill='none' stroke-linecap='round' stroke-linejoin='round'/%3E%3C/svg%3E");
  background-repeat:no-repeat;background-position:right .9rem center;
  padding-right:2.2rem;
}
[data-theme="dark"] select{
  background-image:url("data:image/svg+xml,%3Csvg xmlns='http://www.w3.org/2000/svg' width='12' height='12' viewBox='0 0 12 12'%3E%3Cpath d='M2 4l4 4 4-4' stroke='%239a9aa8' stroke-width='1.6' fill='none' stroke-linecap='round' stroke-linejoin='round'/%3E%3C/svg%3E");
}
.field.invalid input,.field.invalid select,.field.invalid textarea{
  border-color:var(--red);
  box-shadow:0 0 0 4px var(--red-soft);
}
.field-error{font-size:.78rem;color:var(--red);font-weight:600;display:none}
.field.invalid .field-error{display:block}

.contact-form{display:grid;gap:.85rem;margin:1.25rem 0 2rem}
.contact-form .field{margin:0}
.contact-form .notice{margin:0}

/* ---------- Result box ---------- */
.result-box{
  margin-top:1.1rem;padding:1.2rem 1.3rem;border-radius:18px;
  background:linear-gradient(135deg,var(--brand-soft),color-mix(in srgb,var(--brand-3) 12%,transparent));
  border:1px solid var(--brand-ring);
  transition:background .3s ease,border-color .3s ease;
}
.result-box.is-error{
  background:linear-gradient(135deg,var(--red-soft),color-mix(in srgb,var(--red) 6%,transparent));
  border-color:color-mix(in srgb,var(--red) 22%,transparent);
}
.result-box.is-error .result-value{color:var(--red);opacity:.65}
.result-label{
  font-size:.78rem;color:var(--muted);font-weight:800;
  text-transform:uppercase;letter-spacing:.1em;
}
.result-value{
  font-size:clamp(1.9rem,5vw,3rem);font-weight:900;
  letter-spacing:-.04em;margin:.2rem 0 .35rem;
  font-variant-numeric:tabular-nums;
  line-height:1.05;word-break:break-word;
}
.result-value.updated{animation:resultReveal .45s cubic-bezier(.4,0,.2,1)}
.result-explain{color:var(--ink-2);margin:0;font-size:.95rem;line-height:1.55}
.result-actions{display:flex;gap:.5rem;flex-wrap:wrap;margin-top:.85rem}
.result-box > .copy-btn{margin-top:.85rem}
.copy-btn{padding:.55rem .9rem;font-size:.85rem}
.copy-btn.copied{background:var(--green);color:#fff;border-color:var(--green)}

/* ---------- Quick examples ---------- */
.quick-examples{display:flex;flex-wrap:wrap;gap:.45rem;margin-top:.9rem}
.example-chip{
  border:1px solid var(--line);background:var(--surface);
  border-radius:999px;padding:.42rem .7rem;
  font-size:.82rem;font-weight:600;cursor:pointer;
  color:var(--ink-2);
  transition:all var(--t);
  -webkit-tap-highlight-color:transparent;
}
.example-chip:hover{
  background:var(--brand-soft);border-color:var(--brand);
  color:var(--brand);transform:translateY(-1px);
}

/* ---------- Grids ---------- */
.grid{display:grid;gap:1rem}
.grid-2{grid-template-columns:repeat(2,minmax(0,1fr))}
.grid-3{grid-template-columns:repeat(3,minmax(0,1fr))}
.grid-4{grid-template-columns:repeat(4,minmax(0,1fr))}

/* ---------- Sections ---------- */
.section{padding:clamp(2.4rem,4vw,3.7rem) 0}
.section-tight{padding:1.4rem 0}
.section-head{display:flex;align-items:flex-end;justify-content:space-between;gap:1rem;margin-bottom:1.35rem}
.section-head p{max-width:62ch;color:var(--muted);margin:.25rem 0 0}

/* ---------- Tool cards ---------- */
.tool-card,.content-card,.mini-card{
  background:var(--surface);
  border:1px solid var(--line);
  border-radius:var(--radius-sm);
  box-shadow:var(--soft-shadow);
}
.tool-card{
  padding:1.1rem;display:flex;flex-direction:column;gap:.55rem;
  transition:transform var(--t),box-shadow var(--t),border-color var(--t);
}
.tool-card:hover{
  text-decoration:none;transform:translateY(-3px);
  box-shadow:var(--hover-lift);border-color:var(--brand);
}
.tool-card strong{font-size:1.02rem;letter-spacing:-.01em}
.tool-icon{
  width:44px;height:44px;border-radius:13px;
  display:grid;place-items:center;
  background:var(--brand-soft);color:var(--brand);
  font-weight:900;font-size:1.1rem;
  transition:transform var(--t);
}
.tool-card:hover .tool-icon{transform:scale(1.08) rotate(-4deg)}
.tool-card p{color:var(--muted);margin:0;font-size:.93rem;line-height:1.5}

.content-card{padding:1.35rem}
.content-card p,.content-card li{color:var(--ink-2)}
.content-card ul{padding-left:1.2rem}
.content-card h2,.content-card h3{margin-bottom:.6rem}
.formula{
  font-family:"SFMono-Regular",Consolas,"Liberation Mono",Menlo,monospace;
  background:var(--ink);color:#fff;
  border-radius:13px;padding:.85rem 1rem;
  overflow:auto;font-size:.88rem;line-height:1.7;
  white-space:pre-wrap;
}
[data-theme="dark"] .formula{background:#000;color:#e8e8f0}

/* ---------- Notice / warning ---------- */
.notice{
  padding:1rem 1.1rem;border-radius:16px;
  background:color-mix(in srgb,var(--blue) 8%,transparent);
  border:1px solid color-mix(in srgb,var(--blue) 18%,transparent);
  color:var(--ink-2);
}
.warning{
  padding:1rem 1.1rem;border-radius:16px;
  background:color-mix(in srgb,var(--brand-3) 12%,transparent);
  border:1px solid color-mix(in srgb,var(--brand-3) 28%,transparent);
  color:var(--ink-2);
}

/* ---------- Table ---------- */
.table-wrap{overflow:auto;border:1px solid var(--line);border-radius:16px}
table{border-collapse:collapse;width:100%;background:var(--surface)}
th,td{padding:.8rem;border-bottom:1px solid var(--line);text-align:left}
th{background:var(--surface-2);font-size:.86rem;font-weight:700}
tr:last-child td{border-bottom:0}

/* ---------- Footer ---------- */
.footer{
  margin-top:clamp(2rem,4vw,4rem);
  border-top:1px solid var(--line);
  background:color-mix(in srgb,var(--surface) 72%,transparent);
}
.footer-grid{
  display:grid;
  grid-template-columns:minmax(320px,1.45fr) minmax(190px,.65fr) minmax(170px,.55fr);
  gap:clamp(1.5rem,4vw,4rem);
  width:min(100%,var(--max));
  padding:2.5rem var(--gutter) 3rem;margin:auto;
}
.footer-grid > div:first-child{max-width:58ch}
.footer a{color:var(--muted)}
.footer a:hover{color:var(--brand)}
.footer p{color:var(--muted);margin:.5rem 0}
.footer-list{display:grid;gap:.4rem}
.footer h3{font-size:1rem;margin-bottom:.7rem}

/* ---------- Breadcrumbs / page hero ---------- */
.breadcrumbs{font-size:.86rem;color:var(--muted);margin:.65rem 0 1rem}
.breadcrumbs a{color:var(--ink-2)}
.page-hero{padding:1.3rem 0 .4rem}
.page-hero h1{font-size:clamp(2.2rem,4.2vw,4rem);margin-bottom:.75rem}
.page-grid{display:grid;grid-template-columns:minmax(0,1fr) minmax(270px,320px);gap:1.5rem;align-items:start}
.page-grid > .grid{gap:1rem}
.sidebar{position:sticky;top:calc(var(--header-h) + 1rem);display:grid;gap:1rem}

/* ---------- Local history ---------- */
.local-history{display:grid;gap:.5rem}
.history-item{
  border:1px solid var(--line);background:var(--surface);
  border-radius:12px;padding:.6rem .7rem;
  font-size:.84rem;color:var(--ink-2);line-height:1.45;
}
.history-item strong{color:var(--ink)}
.history-empty{font-size:.84rem;color:var(--muted)}

/* ---------- Search ---------- */
.search-box{position:relative}
.search-results{
  position:absolute;left:0;right:0;top:calc(100% + .45rem);
  background:var(--surface);border:1px solid var(--line);
  border-radius:16px;box-shadow:var(--shadow);
  padding:.45rem;display:none;z-index:20;
}
.search-results.show{display:grid;animation:fadeInUp .18s ease}
.search-results a{padding:.7rem;border-radius:12px}
.search-results a:hover{background:var(--surface-2);text-decoration:none}
.search-results a strong{display:block;font-size:.9rem}
.search-results .hint{font-size:.8rem}

.kbd{
  font-family:ui-monospace,monospace;
  border:1px solid var(--line);background:var(--surface);
  border-radius:6px;padding:.1rem .35rem;font-size:.78rem;
}

/* ---------- Consent banner ---------- */
.consent-banner{
  position:fixed;z-index:1000;left:1rem;right:1rem;bottom:1rem;
  max-width:760px;margin:auto;
  display:flex;align-items:center;justify-content:space-between;gap:1rem;
  padding:1.1rem 1.2rem;
  background:var(--surface);border:1px solid var(--line);
  border-radius:18px;box-shadow:var(--shadow);
  animation:fadeInUp .3s ease;
}
.consent-banner p{margin:.25rem 0 0;color:var(--muted)}
.consent-banner a{text-decoration:underline}
.consent-actions{display:flex;gap:.6rem;flex:none}

/* ---------- Toast ---------- */
.toast{
  position:fixed;left:50%;bottom:2rem;transform:translateX(-50%) translateY(120%);
  z-index:1100;
  background:var(--ink);color:var(--surface);
  padding:.8rem 1.3rem;border-radius:13px;
  box-shadow:var(--shadow);font-weight:700;font-size:.9rem;
  display:flex;align-items:center;gap:.5rem;
  pointer-events:none;opacity:0;
  transition:transform .35s cubic-bezier(.4,0,.2,1),opacity .35s ease;
  max-width:90vw;
}
.toast.show{transform:translateX(-50%) translateY(0);opacity:1}
[data-theme="dark"] .toast{background:var(--surface);color:var(--ink);border:1px solid var(--line)}
.toast svg{width:18px;height:18px;color:var(--green);flex:none}

/* ---------- Back to top ---------- */
.back-to-top{
  position:fixed;right:1.2rem;bottom:1.2rem;z-index:90;
  width:46px;height:46px;border-radius:50%;
  border:1px solid var(--line);background:var(--surface);
  box-shadow:var(--soft-shadow);cursor:pointer;
  display:grid;place-items:center;color:var(--brand);
  opacity:0;pointer-events:none;transform:translateY(.5rem);
  transition:opacity var(--t),transform var(--t),background var(--t);
}
.back-to-top.show{opacity:1;pointer-events:auto;transform:translateY(0)}
.back-to-top:hover{background:var(--brand-soft);transform:translateY(-2px)}
.back-to-top svg{width:20px;height:20px}

/* ---------- Animations ---------- */
@keyframes resultReveal{
  0%{opacity:0;transform:translateY(8px) scale(.97)}
  100%{opacity:1;transform:translateY(0) scale(1)}
}
@keyframes fadeInUp{
  from{opacity:0;transform:translateY(10px)}
  to{opacity:1;transform:translateY(0)}
}
@keyframes pulse{
  0%,100%{opacity:1;transform:scale(1)}
  50%{opacity:.5;transform:scale(.85)}
}

@media (prefers-reduced-motion:reduce){
  *,*::before,*::after{
    animation-duration:.01ms!important;
    transition-duration:.01ms!important;
    scroll-behavior:auto!important;
  }
}

/* ---------- Responsive ---------- */
@media (max-width:980px){
  .hero-grid,.page-grid{grid-template-columns:1fr}
  .sidebar{position:static}
  .grid-3,.grid-4{grid-template-columns:repeat(2,minmax(0,1fr))}
  .footer-grid{grid-template-columns:1fr 1fr}
  .footer-grid > div:first-child{grid-column:1/-1}
}

@media (max-width:780px){
  .nav-links{
    display:none;position:absolute;left:var(--gutter);right:var(--gutter);
    top:calc(var(--header-h) - 4px);
    background:var(--surface);border:1px solid var(--line);
    border-radius:18px;padding:.7rem;box-shadow:var(--shadow);
    white-space:normal;
  }
  .nav-links.open{display:grid;justify-content:stretch;align-items:stretch;animation:fadeInUp .2s ease}
  .nav-links > a{width:100%;padding:.65rem .75rem;text-align:left}
  .nav-more{display:none!important}
  .mobile-toggle{display:inline-flex}
  .hero{padding:1.5rem 0 1rem}
  .hero-grid{gap:1.5rem}
  .hero-grid > .panel{display:block}
  .stats{display:none}
  .form-grid,.form-grid.three,.grid-2,.grid-3,.grid-4{grid-template-columns:1fr}
  .section-head{flex-direction:column;align-items:flex-start}
  h1,.page-hero h1{font-size:clamp(2rem,9vw,3rem)}
  .page-hero{padding:1rem 0 .25rem}
  .section-tight{padding:1rem 0}
  .footer-grid{grid-template-columns:1fr;gap:1.35rem;padding-top:2rem;padding-bottom:2.25rem}
  .consent-banner{align-items:stretch;flex-direction:column}
  .consent-actions{display:grid;grid-template-columns:1fr 1fr}
  .mode-tabs{grid-template-columns:1fr 1fr}
  .result-value{font-size:clamp(1.7rem,9vw,2.6rem)}
}

@media (max-width:420px){
  :root{--gutter:1rem}
  .calculator-card{padding:1rem}
  .card-head{flex-wrap:wrap}
  .mode-tab{font-size:.8rem;padding:.55rem .5rem}
}