/* invoiceledger.com/insights: the hub and every guide. The pages are generated by
   tools/cms-build.mjs from the CMS; this file is hand-written and shared by all of them.
   Same language as /feed: Funnel Display headlines, Funnel Sans prose, Geist Mono labels,
   violet #DA65F5 on cream, charcoal and white, light and dark from the system. */
:root{
  --sig:#DA65F5; --sig-ink:#8E2FB3; --cream:#F0EAE5; --char:#141414;
  --bg:#F5F4F2; --card:#FFFFFF; --ink:#141414; --ink-2:#3B3936; --muted:#76716D; --line:rgba(20,20,20,.09);
  --nav:rgba(245,244,242,.74);
  --display:"Funnel Display",-apple-system,BlinkMacSystemFont,"Segoe UI",Roboto,Arial,sans-serif;
  --font:"Funnel Sans","Funnel Display",-apple-system,BlinkMacSystemFont,"Segoe UI",Roboto,Arial,sans-serif;
  --mono:"Geist Mono",ui-monospace,SFMono-Regular,Menlo,monospace;
  --ease:cubic-bezier(.16,1,.3,1);
  --g:clamp(16px,4vw,40px); --w:1180px; --read:720px;
  color-scheme:light dark;
}
@media (prefers-color-scheme:dark){
  :root{--bg:#0E0E0E;--card:#1A1A1A;--ink:#F4F4F4;--ink-2:#CBC7C3;--muted:#8E8A86;--line:rgba(255,255,255,.09);--nav:rgba(14,14,14,.74);--sig-ink:#E7A6F8}
}
*{box-sizing:border-box}
html{-webkit-text-size-adjust:100%;scroll-padding-top:80px}
body{margin:0;min-height:100vh;display:flex;flex-direction:column;background:var(--bg);color:var(--ink);font-family:var(--font);font-size:17px;line-height:1.5;letter-spacing:-.006em;-webkit-font-smoothing:antialiased;-moz-osx-font-smoothing:grayscale}
a{color:inherit}
main{flex:1}
::selection{background:var(--sig);color:#160B20}
.skip{position:absolute;left:-9999px;top:8px;z-index:30;padding:10px 14px;border-radius:10px;background:var(--ink);color:var(--bg);font-family:var(--mono);font-size:12px}
.skip:focus{left:8px}
.k{display:inline-flex;align-items:center;gap:9px;margin:0;font-family:var(--mono);font-size:11.5px;font-weight:500;letter-spacing:.12em;text-transform:uppercase;color:var(--muted)}
.k::before{content:"";width:6px;height:6px;border-radius:50%;background:var(--sig)}
.dot{display:inline-block;width:.18em;height:.18em;margin-left:.035em;border-radius:50%;background:var(--sig)}

/* nav */
.nav{position:sticky;top:0;z-index:10;height:58px;display:flex;align-items:center;background:var(--nav);-webkit-backdrop-filter:saturate(1.8) blur(20px);backdrop-filter:saturate(1.8) blur(20px);border-bottom:1px solid var(--line)}
.nav-in{width:100%;max-width:var(--w);margin:0 auto;padding:0 var(--g);display:flex;align-items:center;justify-content:space-between;gap:16px}
.logo{display:inline-flex;align-items:center;gap:10px;font-family:var(--display);font-size:16.5px;letter-spacing:-.02em;text-decoration:none}
.logo b{font-weight:700;font-size:23px;letter-spacing:-.05em}
.logo .sep{width:1px;height:16px;background:currentColor;opacity:.3}
.logo .wm{font-weight:500;opacity:.85}
.links{display:flex;align-items:center;gap:clamp(12px,2.4vw,26px)}
.links a{font-family:var(--mono);font-size:11.5px;font-weight:500;letter-spacing:.1em;text-transform:uppercase;text-decoration:none;color:var(--muted);transition:color .2s}
.links a:hover{color:var(--ink)}
.links .pill{display:inline-flex;align-items:center;gap:8px;padding:9px 14px;border-radius:999px;background:var(--sig);color:#141414}
.links .pill:hover{color:#141414}
.links .pill i{width:6px;height:6px;border-radius:50%;background:currentColor}
@media (max-width:560px){.links a:not(.pill):nth-child(2){display:none}.logo .wm,.logo .sep{display:none}}

/* hub */
.hero{max-width:var(--w);margin:0 auto;padding:clamp(56px,10vw,120px) var(--g) clamp(28px,4vw,48px)}
.hero h1{margin:18px 0 0;font-family:var(--display);font-weight:700;font-size:clamp(68px,12vw,150px);line-height:.82;letter-spacing:-.05em}
.hero .lede{margin:28px 0 0;max-width:46ch;font-family:var(--display);font-size:clamp(19px,2vw,24px);line-height:1.36;letter-spacing:-.018em;color:var(--muted)}
.grid{max-width:var(--w);margin:0 auto;padding:0 var(--g) clamp(48px,7vw,88px);display:grid;grid-template-columns:repeat(2,minmax(0,1fr));gap:clamp(14px,1.8vw,22px)}
@media (max-width:760px){.grid{grid-template-columns:minmax(0,1fr)}}
.card{position:relative;isolation:isolate;overflow:hidden;display:flex;flex-direction:column;justify-content:space-between;gap:40px;min-height:clamp(280px,26vw,340px);padding:clamp(24px,3vw,34px);border-radius:28px;background:var(--card);color:var(--ink);text-decoration:none;box-shadow:inset 0 0 0 1px var(--line);transition:transform .6s var(--ease),box-shadow .6s var(--ease)}
.card:hover{transform:translateY(-4px);box-shadow:inset 0 0 0 1px var(--line),0 34px 70px -34px rgba(0,0,0,.3)}
.card:focus-visible{outline:2px solid var(--sig);outline-offset:4px}
.card.lead{grid-column:1/-1;min-height:clamp(340px,36vw,460px);background:var(--sig);color:#141414;box-shadow:none}
.card.lead::before{content:"";position:absolute;inset:0;z-index:-1;pointer-events:none;background-image:linear-gradient(90deg,currentColor 1px,transparent 1px);background-size:calc(100% / 12) 100%;opacity:.06}
.card:nth-child(4n+3):not(.lead){background:var(--cream);color:#141414;box-shadow:none}
.card .tag{font-family:var(--mono);font-size:11.5px;font-weight:500;letter-spacing:.1em;text-transform:uppercase;opacity:.6}
.card h2{margin:14px 0 0;max-width:22ch;font-family:var(--display);font-weight:600;font-size:clamp(26px,2.6vw,34px);line-height:1.06;letter-spacing:-.022em;text-wrap:balance}
.card.lead h2{max-width:18ch;font-size:clamp(38px,5.4vw,70px);line-height:1;letter-spacing:-.035em}
.card .sum{margin:16px 0 0;max-width:56ch;font-size:clamp(16px,1.4vw,18px);line-height:1.5;opacity:.7}
.card .row{display:flex;align-items:center;justify-content:space-between;gap:16px}
.card .meta{font-family:var(--mono);font-size:12px;letter-spacing:.08em;text-transform:uppercase;opacity:.6}
.go{flex:none;display:grid;place-items:center;width:42px;height:42px;border-radius:50%;box-shadow:inset 0 0 0 1px color-mix(in srgb,currentColor 24%,transparent);transition:background .3s,color .3s,box-shadow .3s}
.go svg{width:14px;height:14px}
.card:hover .go{background:currentColor;box-shadow:none}
.card:hover .go svg{color:var(--card)}
.card.lead:hover .go svg{color:var(--sig)}
.card:nth-child(4n+3):not(.lead):hover .go svg{color:var(--cream)}
.empty{grid-column:1/-1;padding:80px 0;text-align:center;color:var(--muted);font-family:var(--mono);font-size:12px;letter-spacing:.1em;text-transform:uppercase}
.wrap{max-width:var(--w);margin:0 auto;padding:0 var(--g) clamp(72px,9vw,120px)}
.hub .faq{max-width:none}

/* article */
.art{max-width:var(--w);margin:0 auto;padding:clamp(28px,5vw,56px) var(--g) clamp(72px,9vw,120px)}
.art>*{max-width:var(--read);margin-left:auto;margin-right:auto}
.crumbs{display:flex;gap:10px;font-family:var(--mono);font-size:11.5px;letter-spacing:.08em;text-transform:uppercase;color:var(--muted)}
.crumbs a{text-decoration:none}
.crumbs a:hover{color:var(--ink)}
.art-head{margin-top:clamp(36px,6vw,72px)}
.art-head h1{margin:18px 0 0;font-family:var(--display);font-weight:700;font-size:clamp(38px,5.6vw,68px);line-height:1.02;letter-spacing:-.038em;text-wrap:balance}
.art-head .lede{margin:22px 0 0;font-family:var(--display);font-size:clamp(19px,2vw,24px);line-height:1.38;letter-spacing:-.018em;color:var(--muted)}
.byline{display:flex;flex-wrap:wrap;gap:6px 18px;margin:26px 0 0;padding-top:18px;border-top:1px solid var(--line);font-family:var(--mono);font-size:11.5px;letter-spacing:.08em;text-transform:uppercase;color:var(--muted)}
.tldr{margin-top:36px;padding:22px 24px;border-radius:20px;background:var(--cream);color:#141414}
.tldr .k{color:rgba(20,20,20,.6)}
.tldr p{margin:10px 0 0;font-size:17.5px;line-height:1.55}
@media (prefers-color-scheme:dark){.tldr{background:#1D1A1F;color:var(--ink)}.tldr .k{color:var(--muted)}}
.toc{margin-top:28px;padding:18px 0;border-top:1px solid var(--line);border-bottom:1px solid var(--line)}
.toc ol{margin:12px 0 0;padding:0 0 0 20px;columns:2 240px;column-gap:32px;font-size:15.5px;line-height:1.5;color:var(--ink-2)}
.toc li{break-inside:avoid;padding:3px 0}
.toc a{text-decoration:none}
.toc a:hover{text-decoration:underline;text-decoration-color:var(--sig);text-decoration-thickness:2px;text-underline-offset:3px}
.prose{margin-top:clamp(32px,5vw,48px);font-size:clamp(17.5px,1.5vw,19px);line-height:1.66;color:var(--ink-2)}
.prose p,.prose ul,.prose ol,.prose blockquote,.prose .table{margin:0 0 1.15em}
.prose h2{margin:2.1em 0 .6em;font-family:var(--display);font-weight:600;font-size:clamp(26px,2.8vw,34px);line-height:1.1;letter-spacing:-.025em;color:var(--ink)}
.prose h3{margin:1.7em 0 .45em;font-family:var(--display);font-weight:600;font-size:clamp(20px,2vw,23px);line-height:1.2;letter-spacing:-.018em;color:var(--ink)}
.prose strong{color:var(--ink);font-weight:600}
.prose a{color:var(--ink);text-decoration-color:var(--sig);text-decoration-thickness:2px;text-underline-offset:3px}
.prose a:hover{color:var(--sig-ink)}
.prose ul,.prose ol{padding-left:1.25em}
.prose li{margin:.35em 0;padding-left:.2em}
.prose li::marker{color:var(--sig-ink)}
.prose blockquote{padding:4px 0 4px 20px;border-left:3px solid var(--sig);font-family:var(--display);font-size:1.1em;color:var(--ink)}
.prose hr{border:0;border-top:1px solid var(--line);margin:2em 0}
.prose code{font-family:var(--mono);font-size:.86em;padding:.1em .35em;border-radius:6px;background:var(--line)}
.table{overflow-x:auto;border-radius:16px;box-shadow:inset 0 0 0 1px var(--line)}
.prose table{width:100%;min-width:560px;border-collapse:collapse;font-size:15px;line-height:1.45}
.prose th,.prose td{padding:12px 14px;text-align:left;vertical-align:top;border-bottom:1px solid var(--line)}
.prose thead th{font-family:var(--mono);font-size:11px;font-weight:500;letter-spacing:.08em;text-transform:uppercase;color:var(--muted);background:color-mix(in srgb,var(--line) 50%,transparent)}
.prose tbody th{color:var(--ink);font-weight:600}
.prose tbody tr:last-child>*{border-bottom:0}
.glossary h3{scroll-margin-top:80px}
.glossary h3+p{margin-top:0}

/* faq, call to action, read next */
.faq{margin-top:clamp(48px,7vw,80px)}
.faq h2{margin:0 0 18px;font-family:var(--display);font-weight:600;font-size:clamp(26px,2.8vw,34px);letter-spacing:-.025em}
.faq details{border-top:1px solid var(--line)}
.faq details:last-of-type{border-bottom:1px solid var(--line)}
.faq summary{list-style:none;cursor:pointer;display:flex;justify-content:space-between;gap:20px;padding:20px 0;font-family:var(--display);font-size:clamp(18px,1.7vw,21px);font-weight:500;letter-spacing:-.015em}
.faq summary::-webkit-details-marker{display:none}
.faq summary::after{content:"+";flex:none;font-family:var(--mono);font-size:20px;line-height:1;color:var(--sig-ink);transition:transform .3s var(--ease)}
.faq details[open] summary::after{transform:rotate(45deg)}
.faq details p{margin:0 0 22px;max-width:64ch;font-size:17px;line-height:1.6;color:var(--ink-2)}
.cta{display:flex;flex-wrap:wrap;align-items:flex-end;justify-content:space-between;gap:24px 32px;margin-top:clamp(48px,7vw,80px);padding:clamp(26px,4vw,40px);border-radius:28px;background:var(--char);color:#F4F4F4}
.art>.cta{max-width:var(--read)}
.cta .k{color:rgba(244,244,244,.55)}
.cta h2{margin:14px 0 0;max-width:20ch;font-family:var(--display);font-weight:600;font-size:clamp(26px,3vw,38px);line-height:1.04;letter-spacing:-.03em}
.cta p{margin:14px 0 0;max-width:46ch;color:rgba(244,244,244,.66);font-size:16px}
.cta-b{display:flex;flex-wrap:wrap;align-items:center;gap:12px 18px}
.mbtn{display:inline-flex;align-items:center;gap:12px;padding:16px 22px;border-radius:999px;background:var(--sig);color:#141414;font-family:var(--mono);font-size:12px;font-weight:500;letter-spacing:.1em;text-transform:uppercase;text-decoration:none;white-space:nowrap;transition:transform .4s var(--ease),box-shadow .4s}
.mbtn i{width:7px;height:7px;border-radius:50%;background:currentColor}
.mbtn:hover{transform:translateY(-2px);box-shadow:0 16px 44px -12px rgba(218,101,245,.65)}
.ghost{font-family:var(--mono);font-size:12px;letter-spacing:.1em;text-transform:uppercase;color:rgba(244,244,244,.75);text-underline-offset:4px}
.ghost:hover{color:#fff}
@media (prefers-color-scheme:dark){.cta{background:#1A1A1A;box-shadow:inset 0 0 0 1px var(--line)}}
.related{margin-top:clamp(48px,7vw,80px)}
.related>div{display:grid;gap:10px;margin-top:16px}
.related a{display:block;padding:20px 22px;border-radius:20px;background:var(--card);box-shadow:inset 0 0 0 1px var(--line);text-decoration:none;transition:transform .5s var(--ease),box-shadow .5s}
.related a:hover{transform:translateY(-2px);box-shadow:inset 0 0 0 1px var(--line),0 24px 50px -30px rgba(0,0,0,.35)}
.related b{display:block;font-family:var(--display);font-weight:600;font-size:19px;letter-spacing:-.015em}
.related span{display:block;margin-top:6px;font-size:15px;line-height:1.5;color:var(--muted)}

/* footer */
.foot{border-top:1px solid var(--line)}
.foot-in{max-width:var(--w);margin:0 auto;padding:28px var(--g) calc(28px + env(safe-area-inset-bottom));display:grid;gap:14px}
.foot-brand{margin:0;font-family:var(--display);font-size:15px;color:var(--muted)}
.foot-brand b{color:var(--ink);font-weight:700;letter-spacing:-.04em;margin-right:6px}
.foot nav{display:flex;flex-wrap:wrap;gap:8px 22px}
.foot nav a{font-family:var(--mono);font-size:11px;letter-spacing:.08em;text-transform:uppercase;color:var(--muted);text-decoration:none}
.foot nav a:hover{color:var(--ink)}
.legal{margin:0;max-width:90ch;font-size:12.5px;line-height:1.5;color:var(--muted)}
@media (prefers-reduced-motion:reduce){.card,.related a,.mbtn,.go{transition:none}}