:root {
  --bg: #fbfaf7;
  --surface: #ffffff;
  --ink: #1d2320;
  --muted: #5b6560;
  --line: #e2e0d8;
  --brand: #1f6f4a;
  --brand-ink: #ffffff;
  --accent: #b5562b;
  --soft: #eef5f0;
  --neg: #b42318;
  --radius: 10px;
  --max: 1120px;
  color-scheme: light;
}
@media (prefers-color-scheme: dark) {
  :root:not([data-theme="light"]) {
    --bg: #121614; --surface: #1a201d; --ink: #e7ece9; --muted: #a3ada8;
    --line: #2c3430; --brand: #5cc28f; --brand-ink: #0d1411; --accent: #e08a5f;
    --soft: #1f2a24; --neg: #ff8a80; color-scheme: dark;
  }
}
:root[data-theme="dark"] {
  --bg: #121614; --surface: #1a201d; --ink: #e7ece9; --muted: #a3ada8;
  --line: #2c3430; --brand: #5cc28f; --brand-ink: #0d1411; --accent: #e08a5f;
  --soft: #1f2a24; --neg: #ff8a80; color-scheme: dark;
}

* { box-sizing: border-box; }
html { -webkit-text-size-adjust: 100%; }
body {
  margin: 0; background: var(--bg); color: var(--ink);
  font: 17px/1.65 system-ui, -apple-system, "Segoe UI", Roboto, sans-serif;
}
a { color: var(--brand); text-underline-offset: 2px; }
a:hover { text-decoration-thickness: 2px; }
img { max-width: 100%; height: auto; }
h1, h2, h3 { line-height: 1.25; letter-spacing: -0.01em; }
h1 { font-size: clamp(1.7rem, 4vw, 2.4rem); margin: .3em 0 .4em; }
h2 { font-size: 1.4rem; margin: 1.8em 0 .5em; }
h3 { font-size: 1.12rem; margin: 1.4em 0 .4em; }
.wrap { max-width: var(--max); margin: 0 auto; padding: 0 16px; }
.skip { position: absolute; left: -999px; }
.skip:focus { left: 8px; top: 8px; background: var(--surface); padding: 8px; z-index: 9; }

/* header */
.site-head { background: var(--surface); border-bottom: 1px solid var(--line); }
.site-head .wrap { display: flex; align-items: center; gap: 16px; flex-wrap: wrap; min-height: 60px; }
.logo { font-weight: 800; font-size: 1.2rem; color: var(--ink); text-decoration: none; display: flex; align-items: center; gap: 8px; }
.logo-mark { width: 28px; height: 28px; border-radius: 7px; background: var(--brand); color: var(--brand-ink); display: grid; place-items: center; font-size: .85rem; }
.nav { display: flex; gap: 4px 14px; flex-wrap: wrap; margin-left: auto; align-items: center; }
.nav a { color: var(--ink); text-decoration: none; font-size: .95rem; padding: 4px 0; }
.nav a:hover, .nav a[aria-current="page"] { color: var(--brand); }
.theme-toggle { border: 1px solid var(--line); background: transparent; color: var(--ink); border-radius: 8px; padding: 4px 10px; cursor: pointer; font: inherit; font-size: .85rem; }

/* layout */
.layout { display: grid; grid-template-columns: minmax(0, 1fr); gap: 32px; padding: 20px 0 48px; }
@media (min-width: 1100px) { .layout.has-side { grid-template-columns: minmax(0, 1fr) 300px; } }
.main { min-width: 0; }
.side { display: none; }
@media (min-width: 1100px) { .side { display: block; } .side .sticky { position: sticky; top: 16px; } }
.crumbs { font-size: .85rem; color: var(--muted); margin-top: 8px; }
.crumbs a { color: var(--muted); }
.answer { background: var(--soft); border-left: 4px solid var(--brand); padding: 14px 18px; border-radius: 0 var(--radius) var(--radius) 0; font-size: 1.05rem; }
.meta { color: var(--muted); font-size: .88rem; }
.prose { max-width: 760px; }
.prose table { border-collapse: collapse; width: 100%; font-size: .95rem; margin: 1em 0; display: block; overflow-x: auto; }
.prose th, .prose td { border: 1px solid var(--line); padding: 8px 10px; text-align: left; vertical-align: top; }
.prose th { background: var(--soft); }
.note { border: 1px solid var(--line); background: var(--surface); padding: 12px 16px; border-radius: var(--radius); font-size: .93rem; color: var(--muted); }
.sources { font-size: .92rem; }
.sources li { margin: .3em 0; word-break: break-word; }

/* cards */
.grid { display: grid; gap: 16px; grid-template-columns: repeat(auto-fill, minmax(250px, 1fr)); margin: 16px 0; }
.card { background: var(--surface); border: 1px solid var(--line); border-radius: var(--radius); padding: 16px 18px; text-decoration: none; color: var(--ink); display: block; transition: border-color .15s; }
.card:hover { border-color: var(--brand); }
.card h3 { margin: 0 0 6px; font-size: 1.05rem; color: var(--brand); }
.card p { margin: 0; color: var(--muted); font-size: .93rem; }
.card .tag { font-size: .75rem; text-transform: uppercase; letter-spacing: .05em; color: var(--accent); font-weight: 700; }
.hero { padding: 28px 0 8px; }
.hero p { font-size: 1.12rem; color: var(--muted); max-width: 680px; }

/* calculators */
.calc { display: grid; gap: 20px; grid-template-columns: minmax(0, 1fr); background: var(--surface); border: 1px solid var(--line); border-radius: var(--radius); padding: 18px; margin: 18px 0; }
@media (min-width: 760px) { .calc { grid-template-columns: minmax(0, 1.1fr) minmax(0, .9fr); } }
.calc h2 { margin: 0 0 8px; font-size: 1.15rem; }
.fields { display: grid; grid-template-columns: repeat(auto-fill, minmax(150px, 1fr)); gap: 12px; }
.field label { display: block; font-size: .85rem; font-weight: 600; margin-bottom: 4px; }
.field .inp { display: flex; align-items: center; border: 1px solid var(--line); border-radius: 8px; background: var(--bg); }
.field .inp:focus-within { border-color: var(--brand); outline: 2px solid color-mix(in srgb, var(--brand) 25%, transparent); }
.field .inp span { padding: 0 8px; color: var(--muted); font-size: .9rem; }
.field input[type=number] { width: 100%; border: 0; background: transparent; color: var(--ink); font: inherit; padding: 8px; min-width: 0; }
.field input:focus { outline: none; }
.field.check label { display: flex; gap: 8px; align-items: center; font-weight: 600; margin-top: 22px; }
.calc-actions { margin-top: 12px; }
.btn { border: 1px solid var(--line); background: transparent; color: var(--ink); padding: 6px 12px; border-radius: 8px; cursor: pointer; font: inherit; font-size: .9rem; }
.results { background: var(--soft); border-radius: var(--radius); padding: 14px 16px; align-self: start; }
.result { display: flex; justify-content: space-between; gap: 12px; padding: 6px 0; border-bottom: 1px dashed var(--line); font-size: .95rem; }
.result:last-child { border-bottom: 0; }
.result b { font-variant-numeric: tabular-nums; text-align: right; }
.result.key { font-size: 1.1rem; }
.result.key b { color: var(--brand); }
.result.neg b { color: var(--neg); }
.faq h3 { margin-bottom: .2em; }

/* news */
.news-list { list-style: none; padding: 0; margin: 0; }
.news-list li { padding: 14px 0; border-bottom: 1px solid var(--line); }
.news-list h3 { margin: 0 0 4px; }
.news-list h3 a { text-decoration: none; }
.news-hero { margin: 16px 0; }
.news-hero img { border-radius: var(--radius); border: 1px solid var(--line); display: block; }
blockquote { margin: 1em 0; padding: 4px 16px; border-left: 3px solid var(--accent); color: var(--muted); }

/* ads: empty slots take no space */
.ad-slot { margin: 24px 0; }
.ad-slot:empty { display: none; margin: 0; }
.ad-slot.ad-live::before { content: "Advertisement"; display: block; font-size: .7rem; color: var(--muted); text-transform: uppercase; letter-spacing: .08em; margin-bottom: 4px; }
.dir-link { display: inline-block; margin: 8px 0; padding: 10px 14px; border: 1px solid var(--brand); border-radius: 8px; text-decoration: none; font-weight: 600; }

/* footer */
.site-foot { border-top: 1px solid var(--line); background: var(--surface); padding: 28px 0 20px; font-size: .9rem; color: var(--muted); }
.foot-cols { display: grid; gap: 20px; grid-template-columns: repeat(auto-fill, minmax(180px, 1fr)); }
.site-foot h4 { color: var(--ink); margin: 0 0 6px; font-size: .9rem; }
.site-foot ul { list-style: none; padding: 0; margin: 0; }
.site-foot li { margin: 3px 0; }
.site-foot a { color: var(--muted); }
.network { margin-top: 22px; padding-top: 14px; border-top: 1px solid var(--line); display: flex; flex-wrap: wrap; gap: 6px 14px; align-items: center; }
.network strong { color: var(--ink); }
.network a[aria-current="true"] { color: var(--brand); font-weight: 700; text-decoration: none; }
.disclaimer { margin-top: 14px; font-size: .82rem; }