/* Layout: a working calculator up top beside a cross-section of the window; plain reference sections below. */
:root{
  --bg:#eef2f4; --surface:#ffffff; --ink:#18232b; --muted:#56656f; --line:#d3dce1;
  --frost:#dde7ec; --accent:#b8571a; --accent-ink:#ffffff; --steel:#8b99a3;
  --display:"Bricolage Grotesque", "Segoe UI", system-ui, sans-serif;
  --body:"Figtree", "Segoe UI", system-ui, sans-serif;
  --mono:"JetBrains Mono", ui-monospace, Menlo, monospace;
  color-scheme:light;
}
@media (prefers-color-scheme: dark){:root{
  --bg:#11181d; --surface:#18222a; --ink:#e6edf1; --muted:#9aa9b2; --line:#2a3741;
  --frost:#1e2b34; --accent:#e68542; --accent-ink:#1a0e05; --steel:#6d7c86; color-scheme:dark}}
*{box-sizing:border-box}
html{-webkit-text-size-adjust:100%}
body{margin:0;background:var(--bg);color:var(--ink);font-family:var(--body);font-size:16px;line-height:1.6}
img,svg{max-width:100%}
.wrap{max-width:1080px;margin:0 auto;padding-left:max(16px,env(safe-area-inset-left,0px));padding-right:max(16px,env(safe-area-inset-right,0px))}
h1,h2,h3{font-family:var(--display);line-height:1.15;text-wrap:balance;margin:0}
h1{font-size:clamp(2rem,4.6vw,3.1rem);font-weight:700;letter-spacing:-.02em}
h2{font-size:clamp(1.45rem,2.6vw,1.9rem);font-weight:700}
h3{font-size:1.08rem;font-weight:700}
p{margin:0}
a{color:var(--accent)}
.eyebrow{font-size:.75rem;text-transform:uppercase;letter-spacing:.12em;color:var(--muted);font-weight:600}
header.top{border-bottom:1px solid var(--line)}
header.top .wrap{display:flex;justify-content:space-between;align-items:center;gap:12px;padding-block:14px;flex-wrap:wrap}
.brand{font-family:var(--display);font-weight:700;font-size:1.05rem;color:var(--ink);text-decoration:none}
.top nav{display:flex;gap:18px;font-size:.92rem}
.top nav a{color:var(--muted);text-decoration:none}
.top nav a:hover{color:var(--ink)}

.hero .wrap{display:grid;grid-template-columns:1fr 1fr;gap:40px;padding-block:44px 52px;align-items:start}
.hero .lead{display:flex;flex-direction:column;gap:18px;min-width:0}
.hero .lead p.sub{font-size:1.1rem;color:var(--muted);max-width:34em}
.facts{display:flex;flex-wrap:wrap;gap:8px 18px;font-size:.92rem;color:var(--muted);padding:0;margin:0;list-style:none}
.facts li::before{content:"";display:inline-block;width:6px;height:6px;border-radius:50%;background:var(--accent);margin-right:8px;vertical-align:middle}
svg.section-view{width:100%;max-width:440px;height:auto;margin-top:6px}

.calc{background:var(--surface);border:1px solid var(--line);border-radius:14px;padding:22px;display:flex;flex-direction:column;gap:14px;box-shadow:0 10px 30px -18px rgba(20,40,55,.35);min-width:0}
.calc h2{font-size:1.25rem}
.win{display:grid;grid-template-columns:1fr 1fr 64px 32px;gap:8px;align-items:end}
.win .x{border:0;background:transparent;color:var(--muted);font-size:1.3rem;cursor:pointer;padding:6px 0;height:44px}
.win .x:disabled{visibility:hidden}
label{display:flex;flex-direction:column;gap:5px;font-size:.82rem;font-weight:600;min-width:0}
.hint{font-weight:400;color:var(--muted);font-size:.78rem}
input,select,textarea{font:inherit;font-size:1rem;padding:10px 12px;border:1px solid var(--line);border-radius:8px;background:var(--bg);color:var(--ink);width:100%;min-width:0}
textarea{min-height:70px;resize:vertical}
input:focus-visible,select:focus-visible,textarea:focus-visible,button:focus-visible,a:focus-visible{outline:2px solid var(--accent);outline-offset:2px}
.winlist{display:flex;flex-direction:column;gap:10px}
.addrow{display:flex;justify-content:space-between;align-items:center;gap:12px;flex-wrap:wrap}
.linkbtn{background:transparent;border:1px dashed var(--line);color:var(--ink);font-weight:600;padding:8px 12px;border-radius:8px;cursor:pointer;font:inherit;font-size:.9rem}
.total{display:flex;justify-content:space-between;align-items:baseline;border-top:1px dashed var(--line);padding-top:14px;gap:12px}
.total .amt{font-family:var(--display);font-size:2.2rem;font-weight:700;font-variant-numeric:tabular-nums}
.breakdown{font-family:var(--mono);font-size:.76rem;color:var(--muted);font-variant-numeric:tabular-nums;white-space:pre-line}
.warn{font-size:.85rem;color:var(--accent);font-weight:600}
button.primary{font:inherit;font-weight:600;border:0;border-radius:8px;padding:12px 16px;cursor:pointer;background:var(--accent);color:var(--accent-ink)}
button.primary:disabled{opacity:.6;cursor:wait}
.form{display:flex;flex-direction:column;gap:12px}
.row{display:grid;grid-template-columns:1fr 1fr;gap:12px}
.note{font-size:.82rem;color:var(--muted)}
.ok{background:var(--frost);border-radius:8px;padding:12px;font-size:.92rem}
.hp{position:absolute;left:-9999px;width:1px;height:1px;overflow:hidden}

section.block .wrap{padding-block:46px;display:flex;flex-direction:column;gap:22px}
section.alt{background:var(--frost)}
.grid4{display:grid;grid-template-columns:repeat(4,1fr);gap:18px}
.grid3{display:grid;grid-template-columns:repeat(3,1fr);gap:22px}
.item{display:flex;flex-direction:column;gap:6px;min-width:0}
.item p{color:var(--muted);font-size:.95rem}
.steps{counter-reset:s;display:grid;grid-template-columns:repeat(3,1fr);gap:22px;list-style:none;padding:0;margin:0}
.steps li{counter-increment:s;display:flex;flex-direction:column;gap:6px}
.steps li::before{content:counter(s);font-family:var(--display);font-weight:700;font-size:1.6rem;color:var(--accent)}
.steps p{color:var(--muted);font-size:.95rem}
.tbl{overflow-x:auto}
table{border-collapse:collapse;width:100%;min-width:520px;font-size:.95rem}
th,td{text-align:left;padding:10px 12px;border-bottom:1px solid var(--line)}
th{font-size:.78rem;text-transform:uppercase;letter-spacing:.08em;color:var(--muted)}
td.n{font-variant-numeric:tabular-nums;font-family:var(--mono);font-size:.9rem}
details{border-bottom:1px solid var(--line);padding-block:12px}
summary{cursor:pointer;font-weight:600}
details p{margin-top:8px;color:var(--muted);max-width:65ch}
footer .wrap{padding-block:28px;color:var(--muted);font-size:.85rem;border-top:1px solid var(--line);display:flex;flex-direction:column;gap:6px}

@media (max-width:860px){
  .hero .wrap{grid-template-columns:1fr;gap:28px;padding-block:30px 40px}
  .grid4{grid-template-columns:1fr 1fr}
  .grid3,.steps{grid-template-columns:1fr}
  .top nav{display:none}
}
@media (max-width:440px){.row{grid-template-columns:1fr}.grid4{grid-template-columns:1fr}.win{grid-template-columns:1fr 1fr 56px 28px}}
@media (prefers-reduced-motion:reduce){*{transition:none!important;scroll-behavior:auto!important}}
/* inner pages */
.page .wrap{padding-block:40px 56px;display:flex;flex-direction:column;gap:22px}
.prose{display:flex;flex-direction:column;gap:14px;max-width:70ch}
.prose p,.prose li{color:var(--ink)}
.prose ul{margin:0;padding-left:1.2em;display:flex;flex-direction:column;gap:6px}
.crumb{font-size:.85rem;color:var(--muted)}
.crumb a{color:var(--muted)}
.cta{display:inline-block;background:var(--accent);color:var(--accent-ink);text-decoration:none;font-weight:600;padding:12px 18px;border-radius:8px;align-self:flex-start}
.panel{background:var(--surface);border:1px solid var(--line);border-radius:14px;padding:22px;display:flex;flex-direction:column;gap:14px;min-width:0}
.res{display:grid;grid-template-columns:repeat(3,1fr);gap:14px}
.res .k{font-size:.78rem;text-transform:uppercase;letter-spacing:.08em;color:var(--muted);font-weight:600}
.res .v{font-family:var(--display);font-size:1.6rem;font-weight:700;font-variant-numeric:tabular-nums}
.res .s{font-size:.85rem;color:var(--muted)}
.chip{display:inline-block;padding:2px 10px;border-radius:999px;font-size:.8rem;font-weight:600}
.chip.bad{background:#f6d9c6;color:#7a3208}
.chip.good{background:#d3ebdc;color:#1d5a35}
@media (prefers-color-scheme: dark){.chip.bad{background:#4a2a14;color:#f3c39f}.chip.good{background:#173a26;color:#a8dcbb}}
.src{font-size:.85rem;color:var(--muted)}
.src ol{padding-left:1.2em;margin:6px 0 0;display:flex;flex-direction:column;gap:4px}
.grid2{display:grid;grid-template-columns:1fr 1fr;gap:22px}
.morelinks{display:flex;flex-wrap:wrap;gap:10px}
.morelinks a{border:1px solid var(--line);border-radius:999px;padding:6px 14px;text-decoration:none;color:var(--ink);font-size:.92rem;background:var(--surface)}
@media (max-width:860px){.res,.grid2{grid-template-columns:1fr}}