:root {
  --bg: #F3F7F5; --ink: #12201A; --ink2: #4A5C54; --ink3: #7C8D86;
  --card: #FFFFFF; --hair: rgba(18, 32, 26, .1); --green: #12A150; --green2: #0E8A44; --on-green: #fff;
  --blue: #2F7CF6; --bad: #E03E45; --gold: #D99A00;
  --cell: #FFFFFF; --cellh: #F2F5F4; --cell-line: #DCE3E0;
  --shadow: 0 1px 2px rgba(16, 40, 30, .06), 0 8px 24px -10px rgba(16, 40, 30, .18);
  --sans: -apple-system, BlinkMacSystemFont, "Segoe UI", system-ui, Roboto, "Helvetica Neue", sans-serif;
  --round: ui-rounded, "SF Pro Rounded", -apple-system, system-ui, "Segoe UI", Roboto, sans-serif;
  --mono: ui-monospace, "SF Mono", Menlo, Consolas, "Liberation Mono", monospace;
  color-scheme: light;
}
@media (prefers-color-scheme: dark) {
  :root:not([data-theme="light"]) {
    --bg: #0C1512; --ink: #E9F3EE; --ink2: #A5B8B0; --ink3: #74877F;
    --card: #142019; --hair: rgba(255, 255, 255, .1); --green: #2FC874; --green2: #4ED68A; --on-green: #0B1A12;
    --blue: #5B9BFF; --bad: #FF5A60; --cell: #16211D; --cellh: #1D2A25; --cell-line: #2A3833;
    --shadow: 0 1px 2px rgba(0, 0, 0, .3), 0 10px 28px -10px rgba(0, 0, 0, .5);
    color-scheme: dark;
  }
}
:root[data-theme="dark"] {
  --bg: #0C1512; --ink: #E9F3EE; --ink2: #A5B8B0; --ink3: #74877F;
  --card: #142019; --hair: rgba(255, 255, 255, .1); --green: #2FC874; --green2: #4ED68A; --on-green: #0B1A12;
  --blue: #5B9BFF; --bad: #FF5A60; --cell: #16211D; --cellh: #1D2A25; --cell-line: #2A3833;
  color-scheme: dark;
}
* { box-sizing: border-box; }
html, body { margin: 0; }
body { font: 17px/1.6 var(--sans); color: var(--ink); background: var(--bg); -webkit-font-smoothing: antialiased; }
h1, h2, h3 { font-family: var(--round); line-height: 1.2; letter-spacing: -.01em; }
h1 { font-size: clamp(2rem, 5vw, 2.75rem); margin: .3em 0 .2em; }
h2 { font-size: 1.5rem; margin: 1.8em 0 .5em; }
h3 { font-size: 1.125rem; margin: 0 0 .3em; }
a { color: var(--blue); }
code { font-family: var(--mono); font-size: .92em; }
.wrap { width: min(980px, 100% - 32px); margin: 0 auto; }
.muted { color: var(--ink2); } .small { font-size: .875rem; }
.skip { position: absolute; left: -999px; } .skip:focus { left: 16px; top: 8px; z-index: 9; background: var(--card); padding: 8px 12px; }
:focus-visible { outline: 3px solid var(--blue); outline-offset: 2px; border-radius: 6px; }

.top { position: sticky; top: env(safe-area-inset-top, 0px); z-index: 5; background: color-mix(in srgb, var(--bg) 85%, transparent); backdrop-filter: blur(16px); -webkit-backdrop-filter: blur(16px); border-bottom: 1px solid var(--hair); }
.top-in { display: flex; justify-content: space-between; align-items: center; gap: 12px; min-height: 60px; flex-wrap: wrap; }
.brand { display: inline-flex; align-items: center; gap: 10px; font: 750 1.25rem var(--round); color: var(--ink); text-decoration: none; }
.logo { display: grid; grid-template-columns: 1fr 1fr; gap: 2px; width: 26px; height: 26px; padding: 3px; border-radius: 8px; background: var(--green); }
.logo i { background: rgba(255, 255, 255, .92); border-radius: 2px; }
.logo i:nth-child(4) { background: transparent; box-shadow: inset 0 0 0 2px rgba(255, 255, 255, .92); }
.topnav { display: flex; align-items: center; gap: 4px 18px; flex-wrap: wrap; }
.topnav a:not(.btn) { color: var(--ink2); text-decoration: none; font-weight: 600; font-size: .9375rem; }
.topnav a:not(.btn):hover { color: var(--ink); }
.crumbs { font-size: .875rem; color: var(--ink3); padding-top: 14px; }
.crumbs a { color: var(--ink2); }

.btn { display: inline-flex; align-items: center; justify-content: center; min-height: 44px; padding: .55em 1.3em; border-radius: 999px; font-weight: 650; text-decoration: none; white-space: nowrap; background: var(--green); color: var(--on-green); box-shadow: inset 0 1px 0 rgba(255, 255, 255, .35), 0 6px 16px -8px var(--green); }
.btn:hover { filter: brightness(1.06); }
.btn.small { min-height: 36px; padding: .3em 1em; font-size: .9rem; }
.btn.big { min-height: 52px; padding: .7em 1.8em; font-size: 1.0625rem; }
.btn.ghost { background: var(--card); color: var(--ink); box-shadow: inset 0 0 0 1px var(--hair); }
.row { display: flex; gap: 10px; flex-wrap: wrap; }
.card { background: var(--card); border: 1px solid var(--hair); border-radius: 18px; padding: 16px 18px; box-shadow: var(--shadow); }
.pill { font-size: .75rem; font-weight: 650; color: var(--blue); background: color-mix(in srgb, var(--blue) 12%, transparent); padding: .1em .55em; border-radius: 999px; }

.lede { font-size: 1.1875rem; color: var(--ink2); margin: .2em 0 1.2em; max-width: 40em; }
.kicker { margin: 1.4em 0 0; font-weight: 650; color: hsl(var(--h, 152) 65% 40%); }
.doc { max-width: 780px; }
.doc > p, .doc li { max-width: 42em; }
.sig { display: flex; gap: 12px; align-items: center; font-size: 1.0625rem; overflow-x: auto; }
.fxl { font: italic 600 .9375rem Georgia, serif; color: var(--ink3); }
.args { display: grid; gap: 0; margin: 0; border: 1px solid var(--hair); border-radius: 14px; overflow: hidden; background: var(--card); }
.args div { display: grid; grid-template-columns: minmax(120px, 200px) 1fr; gap: 12px; padding: 10px 16px; }
.args div + div { border-top: 1px solid var(--hair); }
.args dt code { font-weight: 650; } .args dd { margin: 0; color: var(--ink2); }

.sheet { overflow-x: auto; border: 1px solid var(--cell-line); border-radius: 12px; background: var(--cell); margin: 12px 0; }
.xl { border-collapse: collapse; font-size: .9375rem; min-width: 100%; }
.xl th { background: var(--cellh); color: var(--ink3); font: 600 .75rem var(--sans); padding: 4px 8px; border: 1px solid var(--cell-line); }
.xl td { padding: 6px 10px; border: 1px solid var(--cell-line); white-space: nowrap; min-width: 70px; height: 34px; }
.xl td.n { text-align: right; font-variant-numeric: tabular-nums; }
.xl td.hd { font-weight: 650; background: var(--cellh); }
.xl td.tgt { box-shadow: inset 0 0 0 2px var(--green); font-weight: 650; color: var(--green2); }
.xl td.err, .err { color: var(--bad); }
.fbar { display: flex; align-items: center; gap: 10px; padding: 6px 12px; border-radius: 10px; background: var(--cell); border: 1px solid var(--cell-line); overflow-x: auto; }
.fbar code { font-size: 1rem; white-space: nowrap; }
.fbar a { color: var(--green2); text-decoration: none; font-weight: 650; }
.nb { font: 650 .875rem var(--mono); color: var(--ink2); padding-right: 10px; border-right: 1px solid var(--cell-line); }
.examples, .exlist, .steps { padding-left: 0; list-style: none; display: grid; gap: 12px; counter-reset: s; }
.examples .result { margin: 10px 0 0; }
.steps li { counter-increment: s; display: flex; gap: 12px; align-items: baseline; }
.steps li::before { content: counter(s); flex: none; width: 28px; height: 28px; display: grid; place-items: center; border-radius: 50%; background: color-mix(in srgb, var(--green) 15%, transparent); color: var(--green2); font: 700 .875rem var(--round); }
.mistakes, .guide { display: grid; gap: 12px; grid-template-columns: repeat(auto-fit, minmax(240px, 1fr)); }
.mistakes p, .guide p { margin: 0; color: var(--ink2); }
.guide .f { display: inline-block; margin: 4px 0 8px; padding: 3px 10px; border-radius: 8px; background: color-mix(in srgb, var(--green) 10%, transparent); color: var(--green2); font-weight: 600; }
.guide .f a { color: inherit; }
.faq { display: grid; gap: 10px; }
.faq summary, .exlist summary { cursor: pointer; font-weight: 650; }
.faq p { margin: .6em 0 0; color: var(--ink2); }
.exlist .q { font-weight: 650; margin: 0 0 8px; }
.exlist details { margin-top: 8px; color: var(--ink2); }
.opts { display: flex; flex-wrap: wrap; gap: 8px; list-style: none; padding: 0; margin: 0; }
.opts li { padding: 4px 12px; border-radius: 10px; border: 1px solid var(--hair); font-size: .9375rem; }
.pairs { display: grid; gap: 6px; margin: 0; }
.pairs div { display: grid; grid-template-columns: 160px 1fr; gap: 12px; }
.pairs dt { font-weight: 650; } .pairs dd { margin: 0; color: var(--ink2); }
.links { padding-left: 1.2em; }
.chips { list-style: none; padding: 0; display: grid; gap: 8px; }

.cta { display: flex; justify-content: space-between; align-items: center; gap: 16px; flex-wrap: wrap; margin: 2em 0; background: linear-gradient(135deg, color-mix(in srgb, var(--green) 12%, var(--card)), var(--card)); }
.cta h2 { margin: 0; font-size: 1.25rem; } .cta p { margin: 4px 0 0; color: var(--ink2); }
.pager { display: flex; justify-content: space-between; gap: 12px; margin: 2em 0; font-weight: 650; }

.search { width: 100%; min-height: 48px; padding: 0 16px; border-radius: 14px; border: 1px solid var(--hair); background: var(--card); color: var(--ink); font: inherit; }
.fngrid { list-style: none; padding: 0; display: grid; gap: 10px; grid-template-columns: repeat(auto-fill, minmax(200px, 1fr)); }
.fngrid a { display: flex; flex-direction: column; gap: 2px; height: 100%; text-decoration: none; color: var(--ink); padding: 12px 14px; }
.fngrid code { font-weight: 700; color: var(--green2); }
.fngrid span { font-size: .875rem; color: var(--ink2); }
.units { list-style: none; padding: 0; display: grid; gap: 10px; }
.units a { display: flex; gap: 14px; align-items: center; text-decoration: none; color: var(--ink); }
.units a > span:last-child { display: grid; }
.units .muted { font-size: .9375rem; }
.badge { flex: none; width: 48px; height: 48px; border-radius: 14px; display: grid; place-items: center; font: 800 1rem var(--round); color: hsl(var(--h) 70% 40%); background: hsl(var(--h) 80% 60% / .16); }

.hero { display: grid; grid-template-columns: 1.2fr 1fr; gap: 32px; align-items: center; padding: 32px 0 8px; }
.hero h1 { font-size: clamp(2.25rem, 6vw, 3.5rem); letter-spacing: -.03em; }
.demo { transform: rotate(-1.5deg); }
.feat3 { display: grid; grid-template-columns: repeat(3, 1fr); gap: 12px; margin-top: 24px; }
.feat3 h2 { font-size: 1.125rem; margin: 0 0 .3em; } .feat3 p { margin: 0; color: var(--ink2); }

.foot { margin-top: 64px; border-top: 1px solid var(--hair); padding: 32px 0 24px; }
.foot-in { display: grid; grid-template-columns: 2fr 1fr 1fr 1fr; gap: 20px; }
.foot h2 { font-size: .875rem; margin: 0 0 8px; color: var(--ink3); text-transform: uppercase; letter-spacing: .05em; }
.foot-in a:not(.brand) { display: block; color: var(--ink2); text-decoration: none; font-size: .9375rem; padding: 2px 0; }
@media (max-width: 760px) {
  .hero, .feat3, .foot-in { grid-template-columns: 1fr; }
  .args div, .pairs div { grid-template-columns: 1fr; gap: 2px; }
  .topnav a:not(.btn) { font-size: .875rem; }
  body { font-size: 16px; }
  .demo { transform: none; }
}
.doc, main > *, .examples > li, .exlist > li, .mistakes > *, .guide > *, .units > li, .fngrid > li { min-width: 0; }
.opts li, .pairs dd, .exlist p, .examples p { overflow-wrap: anywhere; }
.hero > *, .feat3 > * { min-width: 0; } .row .btn { white-space: normal; }
.answer { font-size: 1.125rem; background: color-mix(in srgb, var(--green) 8%, var(--card)); }
.ex { margin: 12px 0; } .ex .result { margin: 10px 0 0; }
.glist { list-style: none; padding: 0; display: grid; gap: 10px; grid-template-columns: repeat(auto-fill, minmax(280px, 1fr)); }
.glist > li { min-width: 0; }
.glist a { display: grid; gap: 4px; height: 100%; text-decoration: none; color: var(--ink); }
.glist .muted { font-size: .9375rem; }
section > h2 { margin-top: 1.6em; }
.doc p, .doc li, .doc h2, .doc h3, .doc summary, .glist b, .glist span { overflow-wrap: anywhere; }
.glist { grid-template-columns: repeat(auto-fill, minmax(min(280px, 100%), 1fr)); }

/* Hide the badge Netlify injects at serve time; it overlapped the lesson Check button. */
#nl-badge, .nl-badge, #nl-card { display: none !important; }