/* Banc Smartz — a banker's ledger, set for reading.
   Layout: one reading column (~38em) under a slim sticky bar; sidebars become boxed "ledger cards" in the flow. */
:root {
  --paper: #f6f7f4;      /* cool ledger paper */
  --ink: #1c2633;        /* navy ink */
  --muted: #5b6573;
  --rule: #d5dad3;       /* ledger rule */
  --card: #ffffff;
  --green: #2d6a4f;      /* banknote green, the accent */
  --green-soft: #e3eee7;
  --red: #b3261e;        /* NSF red, only for negative figures */
  --display: "Gloock", "Georgia", serif;
  --body: "Literata", "Iowan Old Style", "Georgia", serif;
  --mono: "IBM Plex Mono", ui-monospace, "SFMono-Regular", Menlo, monospace;
  color-scheme: light;
}
@media (prefers-color-scheme: dark) {
  :root:not([data-theme="light"]) {
    --paper: #12171d; --ink: #e5e9ee; --muted: #9aa5b2; --rule: #2a333d; --card: #19202a;
    --green: #7cc4a0; --green-soft: #1d2d27; --red: #ff8a80; color-scheme: dark;
  }
}
:root[data-theme="dark"] {
  --paper: #12171d; --ink: #e5e9ee; --muted: #9aa5b2; --rule: #2a333d; --card: #19202a;
  --green: #7cc4a0; --green-soft: #1d2d27; --red: #ff8a80; color-scheme: dark;
}

*, *::before, *::after { box-sizing: border-box; }
html { -webkit-text-size-adjust: 100%; }
body {
  margin: 0; background: var(--paper); color: var(--ink);
  font-family: var(--body); font-size: 1.0625rem; line-height: 1.7;
  padding-top: env(safe-area-inset-top, 0px); padding-bottom: env(safe-area-inset-bottom, 0px);
}
body::before { content: ""; position: fixed; inset: 0 0 auto; height: env(safe-area-inset-top, 0px); z-index: 10; background: var(--paper); }
a { color: var(--green); text-underline-offset: 3px; }
a:focus-visible, summary:focus-visible { outline: 2px solid var(--green); outline-offset: 3px; border-radius: 2px; }

.wrap, .bar-in, .foot-in {
  max-width: 44rem; margin: 0 auto;
  padding-left: max(16px, env(safe-area-inset-left, 0px));
  padding-right: max(16px, env(safe-area-inset-right, 0px));
}

/* ---- top bar */
.bar { position: sticky; top: env(safe-area-inset-top, 0px); z-index: 5; background: var(--paper); border-bottom: 1px solid var(--rule); }
.bar-in { display: flex; align-items: center; justify-content: space-between; gap: 1rem; padding-block: .6rem; position: relative; }
.brand { font-family: var(--display); font-size: 1.25rem; color: var(--ink); text-decoration: none; }
.menu summary { cursor: pointer; list-style: none; font-family: var(--mono); font-size: .8rem; letter-spacing: .08em; text-transform: uppercase; color: var(--muted); padding: .3rem .6rem; border: 1px solid var(--rule); border-radius: 4px; }
.menu summary::-webkit-details-marker { display: none; }
.menu[open] summary { color: var(--ink); border-color: var(--ink); }
.menu nav { position: absolute; right: max(16px, env(safe-area-inset-right, 0px)); top: calc(100% + 6px); width: min(22rem, calc(100vw - 32px)); max-height: 70vh; overflow-y: auto; background: var(--card); border: 1px solid var(--rule); border-radius: 6px; box-shadow: 0 12px 32px rgba(0,0,0,.12); padding: .5rem 0; }
.menu ol { list-style: none; margin: 0; padding: 0; }
.menu li a { display: flex; gap: .75rem; padding: .35rem 1rem; color: var(--ink); text-decoration: none; font-size: .95rem; line-height: 1.4; }
.menu li a:hover, .menu li a[aria-current] { background: var(--green-soft); }
.menu .num { font-family: var(--mono); color: var(--muted); font-size: .8rem; padding-top: .15rem; }
.toc-part { font-family: var(--mono); font-size: .7rem; letter-spacing: .1em; text-transform: uppercase; color: var(--green); padding: .7rem 1rem .2rem; }

/* ---- cover */
.cover { padding-block: 3.5rem 2rem; }
.cover-head { padding-bottom: 2rem; }
.eyebrow { font-family: var(--mono); font-size: .75rem; letter-spacing: .12em; text-transform: uppercase; color: var(--green); margin: 0 0 .75rem; }
.book-title { font-family: var(--display); font-weight: 400; font-size: clamp(3.2rem, 13vw, 6.5rem); line-height: .95; margin: 0; letter-spacing: -.01em; text-wrap: balance; }
.book-title span { color: var(--green); }
.tagline { font-size: 1.2rem; color: var(--muted); max-width: 30em; margin: 1.25rem 0 1.75rem; font-style: italic; }
.start { display: inline-block; font-family: var(--mono); font-size: .85rem; letter-spacing: .06em; text-transform: uppercase; text-decoration: none; color: var(--paper); background: var(--ink); padding: .75rem 1.25rem; border-radius: 4px; }
.start:hover { background: var(--green); }
.ledger { display: grid; grid-template-columns: repeat(auto-fit, minmax(9rem, 1fr)); border-top: 2px solid var(--ink); border-bottom: 1px solid var(--rule); margin: 0 0 2.5rem; }
.ledger span { font-family: var(--mono); font-size: .72rem; letter-spacing: .06em; text-transform: uppercase; color: var(--muted); padding: .6rem .5rem; border-right: 1px solid var(--rule); }
.ledger span:last-child { border-right: 0; }
.toc { display: grid; gap: 2rem; margin-top: 2.5rem; }
.toc-group h2 { font-family: var(--mono); font-weight: 500; font-size: .75rem; letter-spacing: .12em; text-transform: uppercase; color: var(--green); margin: 0 0 .5rem; padding-bottom: .4rem; border-bottom: 1px solid var(--rule); }
.toc-group ol { list-style: none; margin: 0; padding: 0; }
.toc-group a { display: flex; align-items: baseline; gap: 1rem; padding: .55rem 0; border-bottom: 1px dashed var(--rule); color: var(--ink); text-decoration: none; }
.toc-group a:hover .t { color: var(--green); }
.toc-group .num { font-family: var(--mono); font-size: .85rem; color: var(--muted); font-variant-numeric: tabular-nums; }
.toc-group .t { font-family: var(--display); font-size: 1.35rem; line-height: 1.25; }

/* ---- chapter */
.chapter { padding-block: 3rem 1rem; }
.ch-head { border-bottom: 2px solid var(--ink); padding-bottom: 1.25rem; margin-bottom: 2rem; }
.ch-num { font-family: var(--mono); font-size: .85rem; color: var(--muted); margin: 0 0 .25rem; }
.ch-head h1 { font-family: var(--display); font-weight: 400; font-size: clamp(2.2rem, 7vw, 3.4rem); line-height: 1.05; margin: 0; text-wrap: balance; }
.prose { max-width: 38em; }
.prose > * + * { margin-top: 1.1em; }
.prose p { margin: 0; }
.prose h2 { font-family: var(--display); font-weight: 400; font-size: 1.6rem; line-height: 1.2; margin: 2.2em 0 .2em; text-wrap: balance; }
.prose h3 { font-family: var(--body); font-weight: 600; font-size: 1.1rem; margin: 1.6em 0 .2em; }
.prose ul, .prose ol { padding-left: 1.4em; margin-bottom: 0; }
.prose li + li { margin-top: .35em; }
.prose strong { font-weight: 600; }
.prose blockquote { margin-left: 0; padding-left: 1rem; border-left: 2px solid var(--rule); color: var(--muted); }

/* sidebars: ledger cards */
.aside, .worksheet {
  background: var(--card); border: 1px solid var(--rule); border-top: 3px solid var(--green);
  border-radius: 4px; padding: 1rem 1.25rem 1.1rem; font-size: .95rem; line-height: 1.6;
}
.aside > * + *, .worksheet > * + * { margin-top: .7em; }
.aside h3, .worksheet h3 { font-family: var(--mono); font-weight: 500; font-size: .78rem; letter-spacing: .1em; text-transform: uppercase; color: var(--green); margin: 0 0 .2em; }
.worksheet { border-top-color: var(--ink); background-image: repeating-linear-gradient(to bottom, transparent 0 1.55rem, var(--rule) 1.55rem calc(1.55rem + 1px)); background-color: var(--card); }
.worksheet h3 { color: var(--ink); }

/* quotes */
.quote { border-left: 3px solid var(--green); padding: .25rem 0 .25rem 1.1rem; font-style: italic; font-size: 1.12rem; }
.quote > * + * { margin-top: .4em; }
.quote p:last-child:not(:first-child) { font-style: normal; font-family: var(--mono); font-size: .8rem; color: var(--muted); }

/* tables */
.table-wrap { overflow-x: auto; -webkit-overflow-scrolling: touch; }
.prose table { border-collapse: collapse; width: 100%; font-size: .9rem; line-height: 1.45; }
.prose th, .prose td { text-align: left; vertical-align: top; padding: .5rem .6rem; border-bottom: 1px solid var(--rule); }
.prose th { font-family: var(--mono); font-weight: 500; font-size: .74rem; letter-spacing: .06em; text-transform: uppercase; color: var(--muted); border-bottom: 2px solid var(--ink); }
.prose td { font-variant-numeric: tabular-nums; }
.neg { color: var(--red); }

/* pager */
.pager { display: grid; grid-template-columns: 1fr 1fr; gap: 1rem; padding-block: 2rem 3rem; border-top: 1px solid var(--rule); margin-top: 2rem; }
.pager a { display: block; text-decoration: none; color: var(--ink); padding: .9rem 1rem; border: 1px solid var(--rule); border-radius: 4px; font-family: var(--display); font-size: 1.05rem; line-height: 1.3; min-width: 0; }
.pager a:hover { border-color: var(--green); }
.pager small { display: block; font-family: var(--mono); font-size: .7rem; letter-spacing: .1em; text-transform: uppercase; color: var(--muted); margin-bottom: .3rem; }
.pager .next { text-align: right; }

.foot { border-top: 1px solid var(--rule); }
.foot-in { padding-block: 1.25rem; font-family: var(--mono); font-size: .75rem; color: var(--muted); }

@media (max-width: 520px) {
  body { font-size: 1rem; }
  .pager { grid-template-columns: 1fr; }
  .pager .next { text-align: left; }
}
@media (prefers-reduced-motion: reduce) { * { transition: none !important; } }