/* PriceTag Math, v2 visual design. One file, no framework. Light + dark via prefers-color-scheme. */
:root {
  --bg: #f6f8f7; --surface: #ffffff; --surface-2: #f0f4f2; --ink: #0f1a17; --ink-2: #34433e; --muted: #5a6762;
  --line: #e1e8e5; --line-2: #cfd9d5;
  --brand: #0f766e; --brand-2: #115e59; --brand-3: #0a4a45; --brand-soft: #e5f3f0; --brand-ink: #ffffff; --ring: rgba(15,118,110,.22);
  --accent: #f59e0b; --accent-ink: #8a4b06; --accent-soft: #fff4dc;
  --loss: #b42318; --loss-2: #8f1c13; --loss-soft: #fdecea;
  --head-bg: rgba(246,248,247,.82);
  --mesh-1: rgba(15,118,110,.16); --mesh-2: rgba(245,158,11,.15); --mesh-3: rgba(45,212,191,.13);
  --sh-1: 0 1px 2px rgba(15,26,23,.05), 0 1px 1px rgba(15,26,23,.03);
  --sh-2: 0 1px 2px rgba(15,26,23,.05), 0 8px 24px -6px rgba(15,26,23,.10);
  --sh-3: 0 2px 4px rgba(15,26,23,.04), 0 24px 48px -12px rgba(15,26,23,.20);
  --r-sm: 10px; --r: 14px; --r-lg: 20px;
  --font: "Plus Jakarta Sans", system-ui, -apple-system, "Segoe UI", Roboto, sans-serif;
  --mono: ui-monospace, "Cascadia Mono", Consolas, "SF Mono", monospace;
  color-scheme: light;
}
@media (prefers-color-scheme: dark) {
  :root {
    --bg: #0b1211; --surface: #111a18; --surface-2: #16211f; --ink: #e8f0ed; --ink-2: #c4d0cb; --muted: #94a39d;
    --line: #22302c; --line-2: #2f403b;
    --brand: #2dd4bf; --brand-2: #14b8a6; --brand-3: #0f766e; --brand-soft: #0f2c28; --brand-ink: #04211e; --ring: rgba(45,212,191,.28);
    --accent: #fbbf24; --accent-ink: #fcd34d; --accent-soft: #2a2110;
    --loss: #ff8a7a; --loss-2: #e5675a; --loss-soft: #2e1714;
    --head-bg: rgba(11,18,17,.78);
    --mesh-1: rgba(45,212,191,.13); --mesh-2: rgba(251,191,36,.08); --mesh-3: rgba(20,184,166,.10);
    --sh-1: 0 1px 2px rgba(0,0,0,.4); --sh-2: 0 1px 2px rgba(0,0,0,.4), 0 10px 28px -8px rgba(0,0,0,.6); --sh-3: 0 24px 56px -12px rgba(0,0,0,.7);
    color-scheme: dark;
  }
}

/* ---------- Base ---------- */
*, *::before, *::after { box-sizing: border-box; }
html { -webkit-text-size-adjust: 100%; scroll-padding-top: 84px; }
body { margin: 0; background: var(--bg); color: var(--ink); font: 16px/1.65 var(--font); -webkit-font-smoothing: antialiased; text-rendering: optimizeLegibility; }
body { overflow-x: clip; }
main { display: block; }
a { color: var(--brand); text-decoration-thickness: 1px; text-underline-offset: 3px; }
a:hover { text-decoration-thickness: 2px; }
img, svg { max-width: 100%; }
:focus-visible { outline: 3px solid var(--brand); outline-offset: 2px; border-radius: 6px; }
.wrap { max-width: 1140px; margin: 0 auto; padding: 0 24px; }
.skip { position: absolute; left: 12px; top: -60px; z-index: 100; background: var(--brand); color: var(--brand-ink); padding: 8px 14px; border-radius: 10px; font-weight: 700; }
.skip:focus { top: 10px; }
h1, h2, h3 { color: var(--ink); letter-spacing: -.02em; }
h1 { font-size: clamp(1.85rem, 4.2vw, 2.65rem); line-height: 1.12; margin: 8px 0 12px; font-weight: 800; letter-spacing: -.03em; }
h2 { font-size: 1.45rem; line-height: 1.25; margin: 44px 0 12px; font-weight: 750; }
h3 { font-size: 1.1rem; margin: 24px 0 6px; }
.lead { color: var(--muted); font-size: 1.1rem; line-height: 1.6; margin: 0 0 18px; max-width: 720px; }

/* ---------- Header ---------- */
header.site { position: sticky; top: 0; z-index: 50; background: var(--head-bg); -webkit-backdrop-filter: saturate(1.6) blur(14px); backdrop-filter: saturate(1.6) blur(14px); border-bottom: 1px solid var(--line); }
header.site .wrap { display: flex; align-items: center; gap: 28px; min-height: 66px; }
.logo { display: inline-flex; align-items: center; gap: 10px; font-weight: 800; font-size: 1.16rem; color: var(--ink); text-decoration: none; letter-spacing: -.025em; white-space: nowrap; }
.logo svg { width: 30px; height: 30px; filter: drop-shadow(0 2px 4px rgba(15,118,110,.25)); }
.logo-m { color: var(--brand); }
nav.top { display: flex; gap: 2px; font-size: .94rem; font-weight: 600; margin-right: auto; }
nav.top a { color: var(--ink-2); text-decoration: none; padding: 7px 12px; border-radius: 999px; white-space: nowrap; transition: background .15s, color .15s; }
nav.top a:hover { color: var(--brand); background: var(--brand-soft); }
.head-cta { flex: none; }
@media (max-width: 860px) {
  header.site .wrap { flex-wrap: wrap; gap: 0 12px; min-height: 0; padding-top: 8px; }
  .logo { margin-right: auto; }
  nav.top { order: 3; width: calc(100% + 32px); margin: 4px -16px 0; padding: 0 12px 8px; overflow-x: auto; scrollbar-width: none; font-size: .9rem; }
  nav.top::-webkit-scrollbar { display: none; }
  nav.top a { padding: 6px 11px; background: var(--surface); border: 1px solid var(--line); margin-right: 6px; }
}

/* ---------- Buttons ---------- */
.btn { display: inline-flex; align-items: center; justify-content: center; gap: 8px; font: inherit; font-weight: 700; font-size: .98rem; line-height: 1; border: 1px solid transparent; border-radius: 12px; min-height: 46px; padding: 0 22px; cursor: pointer; text-decoration: none;
  background: linear-gradient(180deg, var(--brand) 0%, var(--brand-2) 100%); color: var(--brand-ink); box-shadow: 0 1px 0 rgba(255,255,255,.18) inset, 0 6px 16px -6px var(--ring), var(--sh-1); transition: transform .15s, box-shadow .15s, filter .15s; }
.btn:hover { filter: brightness(1.07); transform: translateY(-1px); box-shadow: 0 1px 0 rgba(255,255,255,.18) inset, 0 10px 22px -8px var(--ring), var(--sh-1); text-decoration: none; }
.btn:active { transform: translateY(0); }
.btn.ghost { background: var(--surface); color: var(--ink-2); border-color: var(--line-2); box-shadow: var(--sh-1); }
.btn.ghost:hover { border-color: var(--brand); color: var(--brand); filter: none; }
.btn-sm { min-height: 38px; padding: 0 16px; font-size: .9rem; border-radius: 10px; }
.btn-lg { min-height: 52px; padding: 0 26px; font-size: 1.02rem; }

/* ---------- Home hero ---------- */
.hero { position: relative; padding: 64px 0 40px; }
.hero::before { content: ""; position: absolute; z-index: -1; top: 0; bottom: 0; left: calc(50% - 50vw); right: calc(50% - 50vw);
  background: radial-gradient(42% 60% at 12% 18%, var(--mesh-1), transparent 70%), radial-gradient(36% 50% at 88% 8%, var(--mesh-2), transparent 70%), radial-gradient(45% 55% at 72% 75%, var(--mesh-3), transparent 70%);
  -webkit-mask-image: linear-gradient(#000 60%, transparent); mask-image: linear-gradient(#000 60%, transparent); }
.hero::after { content: ""; position: absolute; z-index: -1; inset: 0 calc(50% - 50vw); opacity: .5;
  background-image: linear-gradient(var(--line) 1px, transparent 1px), linear-gradient(90deg, var(--line) 1px, transparent 1px); background-size: 44px 44px;
  -webkit-mask-image: radial-gradient(60% 70% at 50% 30%, #000 10%, transparent 75%); mask-image: radial-gradient(60% 70% at 50% 30%, #000 10%, transparent 75%); }
.hero-in { display: grid; grid-template-columns: minmax(0, 1.12fr) minmax(0, .88fr); gap: 56px; align-items: center; }
.eyebrow { display: inline-flex; align-items: center; gap: 8px; margin: 0 0 14px; padding: 5px 12px 5px 10px; border-radius: 999px; background: var(--surface); border: 1px solid var(--line); box-shadow: var(--sh-1); font-size: .84rem; font-weight: 700; color: var(--brand); }
.eyebrow::before { content: ""; width: 8px; height: 8px; border-radius: 50%; background: var(--accent); box-shadow: 0 0 0 3px var(--accent-soft); }
.hero h1 { font-size: clamp(2.1rem, 5.2vw, 3.5rem); line-height: 1.06; letter-spacing: -.035em; margin: 0 0 18px; }
.hl { color: var(--brand); background: linear-gradient(transparent 64%, rgba(245,158,11,.32) 64%, rgba(245,158,11,.32) 92%, transparent 92%); padding: 0 .06em; }
.hero .lead { font-size: 1.16rem; max-width: 560px; }
.hero-cta { display: flex; flex-wrap: wrap; gap: 12px; margin: 26px 0 22px; }
.trust { list-style: none; padding: 0; margin: 0; display: flex; flex-wrap: wrap; gap: 8px 18px; }
.trust li { position: relative; padding-left: 26px; font-size: .92rem; font-weight: 600; color: var(--ink-2); }
.trust li::before { content: ""; position: absolute; left: 0; top: 50%; width: 18px; height: 18px; margin-top: -9px; border-radius: 50%; background: var(--brand-soft); }
.trust li::after { content: ""; position: absolute; left: 6px; top: 50%; width: 7px; height: 4px; margin-top: -4px; border-left: 2px solid var(--brand); border-bottom: 2px solid var(--brand); transform: rotate(-45deg); }

/* Hero illustration: a stylised order receipt */
.hero-art { position: relative; padding: 48px 10px 46px 28px; }
.hero-tag { position: absolute; width: 190px; height: 190px; right: -34px; top: -34px; transform: rotate(18deg); fill: var(--brand); opacity: .16; }
.hero-tag circle { fill: var(--bg); }
.mini { position: relative; background: var(--surface); border: 1px solid var(--line); border-radius: var(--r-lg); box-shadow: var(--sh-3); padding: 18px 20px 20px; font-size: .9rem; }
.mini-h { display: flex; align-items: center; gap: 10px; font-weight: 700; font-size: .82rem; color: var(--muted); padding-bottom: 12px; border-bottom: 1px solid var(--line); }
.mini-dots { display: inline-flex; gap: 5px; }
.mini-dots i { width: 9px; height: 9px; border-radius: 50%; background: var(--line-2); }
.mini-dots i:first-child { background: var(--accent); }
.mini-rows p { display: flex; justify-content: space-between; gap: 12px; margin: 0; padding: 7px 0; border-bottom: 1px dashed var(--line); color: var(--muted); }
.mini-rows b { color: var(--ink); font-variant-numeric: tabular-nums; }
.mini-rows b.neg { color: var(--ink-2); font-weight: 600; }
.mini-big { display: flex; align-items: baseline; flex-wrap: wrap; gap: 4px 12px; margin: 14px 0 12px; padding: 14px 16px; border-radius: var(--r); background: var(--brand-soft); }
.mini-big span { flex-basis: 100%; font-size: .78rem; font-weight: 700; text-transform: uppercase; letter-spacing: .06em; color: var(--brand); }
.mini-big strong { font-size: 2.1rem; line-height: 1; letter-spacing: -.03em; color: var(--brand); font-variant-numeric: tabular-nums; }
.mini-big em { font-style: normal; font-size: .8rem; font-weight: 700; color: var(--accent-ink); background: var(--accent-soft); padding: 3px 9px; border-radius: 999px; }
.mini-bar { display: flex; height: 8px; border-radius: 999px; overflow: hidden; gap: 3px; }
.mini-bar i:nth-child(1) { background: var(--accent); } .mini-bar i:nth-child(2) { background: var(--line-2); } .mini-bar i:nth-child(3) { background: var(--brand); }
.mini-key { display: flex; gap: 14px; margin-top: 8px; font-size: .74rem; font-weight: 600; color: var(--muted); }
.mini-key span::before { content: ""; display: inline-block; width: 8px; height: 8px; border-radius: 2px; margin-right: 5px; background: var(--accent); }
.mini-key span:nth-child(2)::before { background: var(--line-2); } .mini-key span:nth-child(3)::before { background: var(--brand); }
.chip { position: absolute; display: flex; flex-direction: column; background: var(--surface); border: 1px solid var(--line); border-radius: var(--r); box-shadow: var(--sh-2); padding: 9px 14px; line-height: 1.25; }
.chip b { font-size: 1.05rem; color: var(--ink); font-variant-numeric: tabular-nums; }
.chip span { font-size: .72rem; font-weight: 600; color: var(--muted); }
.chip-a { left: 0; top: 0; }
.chip-b { right: 0; bottom: 0; }
.chip-b b { color: var(--accent-ink); }
@media (max-width: 900px) {
  .hero { padding: 36px 0 20px; }
  .hero-in { grid-template-columns: 1fr; gap: 28px; }
  .hero-art { max-width: 440px; width: 100%; margin: 0 auto; padding: 46px 0 44px; }
  .hero-tag { width: 140px; height: 140px; right: 0; top: -6px; }
  .hero-cta .btn { flex: 1 1 200px; }
  .chip-a { left: auto; right: 10px; top: 0; }
  .chip-b { right: auto; left: 10px; }
}

/* ---------- Home categories + cards ---------- */
.cat-sec { margin-top: 12px; }
.cat { display: flex; align-items: center; gap: 12px; margin: 40px 0 16px; font-size: 1.35rem; scroll-margin-top: 90px; }
.cat-ico { display: inline-grid; place-items: center; flex: none; width: 38px; height: 38px; border-radius: 11px; background: linear-gradient(180deg, var(--brand), var(--brand-2)); color: var(--brand-ink); box-shadow: 0 6px 14px -6px var(--ring); }
.cat-ico svg { width: 20px; height: 20px; }
.related { display: grid; grid-template-columns: repeat(auto-fill, minmax(260px, 1fr)); gap: 16px; margin: 0 0 12px; }
.card { position: relative; display: flex; flex-direction: column; gap: 6px; background: var(--surface); border: 1px solid var(--line); border-radius: var(--r-lg); padding: 20px 20px 18px; text-decoration: none; color: var(--ink); box-shadow: var(--sh-1);
  transition: transform .2s ease, box-shadow .2s ease, border-color .2s ease; }
.card:hover { transform: translateY(-3px); box-shadow: var(--sh-2); border-color: color-mix(in srgb, var(--brand) 45%, var(--line)); text-decoration: none; }
.card-ico { display: inline-grid; place-items: center; width: 38px; height: 38px; border-radius: 11px; background: var(--brand-soft); color: var(--brand); margin-bottom: 8px; transition: background .2s, color .2s; }
.card-ico svg { width: 19px; height: 19px; }
.card:hover .card-ico { background: var(--brand); color: var(--brand-ink); }
.card b { font-size: 1.04rem; line-height: 1.3; letter-spacing: -.01em; }
.card-d { color: var(--muted); font-size: .92rem; line-height: 1.5; }
.card-go { margin-top: auto; padding-top: 12px; font-size: .86rem; font-weight: 700; color: var(--brand); }
.card-go i { display: inline-block; font-style: normal; transition: transform .2s; }
.card:hover .card-go i { transform: translateX(4px); }

/* ---------- Calculator page ---------- */
.page-head { position: relative; padding: 30px 0 6px; }
.page-head::before { content: ""; position: absolute; z-index: -1; top: 0; bottom: -80px; left: calc(50% - 50vw); right: calc(50% - 50vw);
  background: radial-gradient(40% 70% at 10% 0%, var(--mesh-1), transparent 70%), radial-gradient(30% 60% at 90% 0%, var(--mesh-2), transparent 70%); }
.crumbs { display: flex; flex-wrap: wrap; align-items: center; gap: 8px; font-size: .86rem; font-weight: 600; color: var(--muted); margin: 0 0 6px; }
.crumbs a { color: var(--muted); text-decoration: none; }
.crumbs a:hover { color: var(--brand); }
.pills { list-style: none; display: flex; flex-wrap: wrap; gap: 8px; padding: 0; margin: 0 0 8px; }
.pills li { font-size: .8rem; font-weight: 700; color: var(--ink-2); background: var(--surface); border: 1px solid var(--line); border-radius: 999px; padding: 4px 11px; }
.pills li:first-child { color: var(--brand); background: var(--brand-soft); border-color: transparent; }
.calc { display: grid; grid-template-columns: minmax(0, 1.2fr) minmax(0, 1fr); gap: 22px; margin: 22px 0 8px; align-items: start; }
.panel { background: var(--surface); border: 1px solid var(--line); border-radius: var(--r-lg); box-shadow: var(--sh-2); padding: 24px; }
.panel-h { display: flex; align-items: center; justify-content: space-between; gap: 12px; margin-bottom: 18px; }
.panel h2 { margin: 0; font-size: 1.08rem; }
.live { display: inline-flex; align-items: center; gap: 7px; font-size: .76rem; font-weight: 700; text-transform: uppercase; letter-spacing: .06em; color: var(--brand); }
.live i { width: 8px; height: 8px; border-radius: 50%; background: var(--brand); box-shadow: 0 0 0 0 var(--ring); animation: pulse 2.4s infinite; }
@keyframes pulse { 0% { box-shadow: 0 0 0 0 var(--ring); } 70% { box-shadow: 0 0 0 8px transparent; } 100% { box-shadow: 0 0 0 0 transparent; } }
.fields { display: grid; grid-template-columns: 1fr 1fr; gap: 18px 18px; }
.field { display: flex; flex-direction: column; gap: 6px; min-width: 0; }
.field[hidden] { display: none; }
.field.wide { grid-column: 1 / -1; }
.field label { font-size: .88rem; font-weight: 650; color: var(--ink-2); line-height: 1.35; }
.field small { color: var(--muted); font-size: .79rem; line-height: 1.4; }
.inp { position: relative; display: block; }
.field input, .field select { width: 100%; font: inherit; font-size: 1rem; font-weight: 600; font-variant-numeric: tabular-nums; height: 48px; padding: 0 14px; border: 1.5px solid var(--line-2); border-radius: 12px; background: var(--surface); color: var(--ink); min-width: 0;
  transition: border-color .15s, box-shadow .15s, background .15s; }
.field input:hover, .field select:hover { border-color: color-mix(in srgb, var(--brand) 40%, var(--line-2)); }
.field input:focus, .field select:focus { outline: none; border-color: var(--brand); box-shadow: 0 0 0 4px var(--ring); }
.field input[type=number] { -moz-appearance: textfield; appearance: textfield; }
.field input::-webkit-outer-spin-button, .field input::-webkit-inner-spin-button { -webkit-appearance: none; margin: 0; }
.adorn { position: absolute; top: 0; bottom: 0; display: flex; align-items: center; font-weight: 700; color: var(--muted); pointer-events: none; }
.adorn.pre { left: 14px; } .adorn.suf { right: 14px; }
.has-pre input { padding-left: 30px; } .has-suf input { padding-right: 34px; }
.inp:focus-within .adorn { color: var(--brand); }
.field select { -webkit-appearance: none; appearance: none; padding-right: 40px; cursor: pointer; font-weight: 600; }
.is-select::after { content: ""; position: absolute; right: 16px; top: 50%; width: 8px; height: 8px; margin-top: -6px; border-right: 2px solid var(--muted); border-bottom: 2px solid var(--muted); transform: rotate(45deg); pointer-events: none; }
.field input[type=date] { padding-right: 10px; }
.field.check { flex-direction: row; align-items: center; gap: 10px; padding: 12px 14px; border: 1.5px dashed var(--line-2); border-radius: 12px; }
.field.check input { width: 20px; height: 20px; flex: none; accent-color: var(--brand); margin: 0; box-shadow: none; }
.field.check label { font-weight: 600; }
details.more { grid-column: 1 / -1; background: var(--surface-2); border: 1px solid var(--line); border-radius: var(--r); padding: 0; }
details.more summary { list-style: none; cursor: pointer; font-weight: 700; font-size: .92rem; color: var(--brand); padding: 13px 16px; display: flex; align-items: center; gap: 10px; border-radius: var(--r); }
details.more summary::-webkit-details-marker, .faq summary::-webkit-details-marker { display: none; }
details.more summary::before { content: ""; width: 7px; height: 7px; border-right: 2px solid currentColor; border-bottom: 2px solid currentColor; transform: rotate(-45deg); transition: transform .2s; flex: none; }
details.more[open] summary::before { transform: rotate(45deg); }
details.more .fields { padding: 4px 16px 16px; }
.btns { display: flex; gap: 10px; margin-top: 22px; padding-top: 20px; border-top: 1px solid var(--line); }
.btns .btn:first-child { flex: 1 1 auto; max-width: 220px; }

/* Results */
.results { position: sticky; top: 84px; padding: 10px; }
.results .big { position: relative; overflow: hidden; border-radius: 15px; padding: 22px 22px 24px; color: #fff; background: radial-gradient(120% 140% at 100% 0%, rgba(255,255,255,.16), transparent 50%), linear-gradient(140deg, #0f766e 0%, #115e59 55%, #0b4440 100%); box-shadow: 0 14px 30px -14px rgba(15,118,110,.6); }
.results .big::after { content: ""; position: absolute; right: -26px; bottom: -34px; width: 130px; height: 130px; opacity: .12; transform: rotate(14deg);
  background: #fff;
  mask: url("data:image/svg+xml,%3Csvg xmlns='http://www.w3.org/2000/svg' viewBox='0 0 32 32'%3E%3Cpath d='M3 15.5V5a2 2 0 0 1 2-2h10.5a2 2 0 0 1 1.4.6l11.5 11.5a2 2 0 0 1 0 2.8L18 28.3a2 2 0 0 1-2.8 0L3.6 16.9A2 2 0 0 1 3 15.5Zm6.5-3.6a2.4 2.4 0 1 0 0-4.8 2.4 2.4 0 0 0 0 4.8Z' fill-rule='evenodd'/%3E%3C/svg%3E") center/contain no-repeat; }
.big-l { display: block; position: relative; font-size: .78rem; font-weight: 700; text-transform: uppercase; letter-spacing: .07em; color: rgba(255,255,255,.88); }
.results .big strong { display: block; position: relative; margin-top: 6px; font-size: clamp(2.2rem, 4.6vw, 2.9rem); font-weight: 800; line-height: 1.08; letter-spacing: -.035em; font-variant-numeric: tabular-nums; overflow-wrap: anywhere; }
.results.is-loss .big { background: radial-gradient(120% 140% at 100% 0%, rgba(255,255,255,.14), transparent 50%), linear-gradient(140deg, #b42318 0%, #8f1c13 100%); box-shadow: 0 14px 30px -14px rgba(180,35,24,.55); }
.results dl { margin: 12px 4px 0; display: grid; grid-template-columns: minmax(0, 1fr) auto; font-size: .94rem; }
.results dt, .results dd { padding: 10px 12px; border-bottom: 1px solid var(--line); }
.results dt { color: var(--muted); }
.results dd { margin: 0; text-align: right; font-weight: 700; font-variant-numeric: tabular-nums; color: var(--ink); }
.results dl .total { background: var(--brand-soft); border-bottom-color: transparent; color: var(--ink); font-weight: 700; margin: 6px 0; }
.results dt.total { border-radius: 10px 0 0 10px; }
.results dd.total { border-radius: 0 10px 10px 0; color: var(--brand); }
.results.is-loss dd.total { color: var(--loss); }
.calc-note { margin: 12px 4px 0; font-size: .86rem; color: var(--ink-2); background: var(--accent-soft); border-left: 3px solid var(--accent); padding: 10px 12px; border-radius: 8px; }
.res-foot { margin: 12px 4px 4px; font-size: .78rem; color: var(--muted); text-align: center; }
.flash { animation: flash .38s cubic-bezier(.2,.7,.3,1); }
@keyframes flash { from { opacity: .25; transform: translateY(4px); } to { opacity: 1; transform: none; } }
@media (max-width: 860px) {
  .calc { grid-template-columns: 1fr; }
  .results { position: static; }
}
@media (max-width: 520px) {
  .wrap { padding: 0 16px; }
  .panel { padding: 18px 16px; border-radius: 18px; }
  .results { padding: 8px; }
  .fields { grid-template-columns: 1fr; gap: 16px; }
  .btns .btn { flex: 1 1 0; max-width: none; }
  details.more .fields { padding: 4px 12px 14px; }
}

/* ---------- Article ---------- */
article { max-width: 740px; font-size: 1.03rem; line-height: 1.75; margin-top: 18px; }
article p, article li { color: var(--ink-2); }
article b { color: var(--ink); }
article h2 { margin-top: 48px; }
article ul { padding-left: 0; list-style: none; }
article li { position: relative; padding-left: 24px; margin: 8px 0; }
article li::before { content: ""; position: absolute; left: 4px; top: .7em; width: 7px; height: 7px; border-radius: 2px; background: var(--brand); transform: rotate(45deg); }
.formula { position: relative; background: var(--surface); border: 1px solid var(--line); border-radius: var(--r); box-shadow: var(--sh-1); padding: 36px 18px 16px; font-family: var(--mono); font-size: .9rem; line-height: 1.9; color: var(--ink); overflow-x: auto; }
.formula::before { content: "Formula"; position: absolute; left: 18px; top: 12px; font: 700 .7rem/1 var(--font); text-transform: uppercase; letter-spacing: .1em; color: var(--accent-ink); }
.formula::after { content: ""; position: absolute; left: 0; top: 14px; bottom: 14px; width: 3px; border-radius: 0 3px 3px 0; background: var(--accent); }
table.ex { border-collapse: separate; border-spacing: 0; width: 100%; background: var(--surface); border: 1px solid var(--line); border-radius: var(--r); overflow: hidden; font-size: .95rem; box-shadow: var(--sh-1); }
table.ex th { background: var(--surface-2); font-size: .76rem; font-weight: 700; text-transform: uppercase; letter-spacing: .06em; color: var(--muted); }
table.ex th, table.ex td { border-bottom: 1px solid var(--line); padding: 11px 16px; text-align: left; }
table.ex tr:last-child td { border-bottom: 0; }
table.ex tr:nth-child(even) td { background: color-mix(in srgb, var(--surface-2) 45%, transparent); }
table.ex td:last-child, table.ex th:last-child { text-align: right; font-variant-numeric: tabular-nums; white-space: nowrap; }
table.ex td { color: var(--ink-2); }
.faq { background: var(--surface); border: 1px solid var(--line); border-radius: var(--r-lg); box-shadow: var(--sh-1); overflow: hidden; }
.faq details + details { border-top: 1px solid var(--line); }
.faq summary { list-style: none; cursor: pointer; display: flex; justify-content: space-between; align-items: center; gap: 16px; padding: 16px 20px; font-weight: 700; color: var(--ink); line-height: 1.4; }
.faq summary::after { content: "+"; flex: none; display: grid; place-items: center; width: 28px; height: 28px; border-radius: 50%; background: var(--surface-2); color: var(--brand); font-size: 1.2rem; font-weight: 600; line-height: 1; transition: transform .2s, background .2s; }
.faq summary:hover { color: var(--brand); }
.faq details[open] summary::after { transform: rotate(45deg); background: var(--brand-soft); }
.faq details p { margin: -4px 20px 18px; color: var(--ink-2); }
.notice { background: var(--accent-soft); border: 1px solid color-mix(in srgb, var(--accent) 30%, transparent); border-radius: var(--r); padding: 14px 16px; font-size: .92rem; color: var(--ink-2); }
.sources { font-size: .92rem; color: var(--muted); }
.updated { margin-top: 36px; padding-top: 16px; border-top: 1px solid var(--line); font-size: .86rem; color: var(--muted); }
.rel-sec h2 { margin-top: 56px; }
.sheet { background: var(--surface); border: 1px solid var(--line); border-radius: var(--r-lg); box-shadow: var(--sh-1); padding: 8px 28px; }
@media (max-width: 520px) { .sheet { padding: 4px 18px; } table.ex th, table.ex td { padding: 10px 12px; } .faq summary { padding: 14px 16px; } .faq details p { margin: -4px 16px 16px; } }

/* ---------- Footer ---------- */
footer.site { margin-top: 80px; background: var(--surface); border-top: 1px solid var(--line); color: var(--muted); font-size: .92rem; }
.foot-grid { display: grid; grid-template-columns: 1.2fr 2fr .8fr; gap: 36px; padding-top: 48px; padding-bottom: 32px; }
.foot-brand p { margin: 12px 0 0; max-width: 300px; line-height: 1.6; }
.foot-h { margin: 0 0 12px; font-size: .74rem; font-weight: 800; text-transform: uppercase; letter-spacing: .1em; color: var(--ink); }
.foot-col ul { list-style: none; margin: 0; padding: 0; }
.foot-col li { margin: 0 0 9px; break-inside: avoid; }
.foot-calcs ul { columns: 2; column-gap: 28px; }
footer.site a { color: var(--ink-2); text-decoration: none; }
footer.site a:hover { color: var(--brand); }
footer.site .logo { color: var(--ink); }
.foot-bar { display: flex; flex-wrap: wrap; justify-content: space-between; gap: 6px 24px; padding-top: 18px; padding-bottom: 28px; border-top: 1px solid var(--line); font-size: .84rem; }
@media (max-width: 860px) { .foot-grid { grid-template-columns: 1fr 1fr; } .foot-brand { grid-column: 1 / -1; } .foot-calcs ul { columns: 1; } }
@media (max-width: 520px) { .foot-grid { gap: 28px 20px; padding-top: 36px; } }

/* ---------- Motion preferences ---------- */
@media (prefers-reduced-motion: reduce) {
  *, *::before, *::after { animation: none !important; transition: none !important; scroll-behavior: auto !important; }
  .card:hover, .btn:hover { transform: none; }
}