:root {
  --paper: #f2f1ed;
  --ink: #26251e;
  --signal: #f54e00;
  --surface: #ebeae5;
  --gold: #c08532;
  --crimson: #cf2d56;
  --line: #e6e5e0;
  --quiet-ink: #55534b;
  --link-ink: #a43400;
  --hover-ink: #a71c42;
  --border-ink: #aaa79a;
  --humanist: "Candara", "Segoe UI", "Trebuchet MS", ui-sans-serif, system-ui, sans-serif;
  --body-size: 1.125rem;
  --interface-size: 1rem;
  --reading-height: 1.7;
  --measure: 66ch;
  --rail-width: 16.25rem;
  --page-width: 82rem;
  --pill: 999rem;
  --tap: 2.75rem;
  --space-xs: .5rem;
  --space-sm: .875rem;
  --space-md: 1.5rem;
  --space-lg: 2.5rem;
  --space-xl: 4rem;
  --space-xxl: 6rem;
}

* { box-sizing: border-box; }
html { color-scheme: light; scroll-padding-top: var(--space-md); }
body { margin: 0; background: var(--paper); color: var(--ink); font-family: var(--humanist); font-size: var(--body-size); line-height: var(--reading-height); }
button, input { font: inherit; }
a { color: var(--link-ink); text-decoration-thickness: .075em; text-underline-offset: .22em; overflow-wrap: anywhere; }
a:hover { color: var(--hover-ink); }
a:focus-visible, button:focus-visible, input:focus-visible { outline: .2rem solid var(--ink); outline-offset: .2rem; }
[hidden] { display: none !important; }
::selection { background: var(--ink); color: var(--paper); }

.handbook__layout { display: grid; grid-template-columns: var(--rail-width) minmax(0, 1fr); gap: clamp(2.5rem, 6vw, 6rem); max-width: var(--page-width); margin-inline: auto; padding: var(--space-lg) var(--space-lg) 0; align-items: start; }
.handbook__skip { position: fixed; z-index: 10; left: var(--space-md); top: var(--space-md); padding: var(--space-sm) var(--space-md); min-height: var(--tap); background: var(--ink); color: var(--paper); border-radius: var(--pill); transform: translateY(-200%); }
.handbook__skip:focus { transform: translateY(0); color: var(--paper); }

.side-index { position: sticky; top: var(--space-lg); max-height: calc(100dvh - 5rem); overflow-y: auto; padding-right: var(--space-md); border-right: 1px solid var(--line); scrollbar-width: thin; scrollbar-color: var(--border-ink) var(--paper); }
.side-index__brand { display: flex; flex-direction: column; justify-content: center; min-height: var(--tap); color: var(--ink); text-decoration: none; line-height: 1.35; }
.side-index__name { font-size: 1.9rem; font-weight: 750; letter-spacing: -.055em; }
.side-index__name::before { content: ""; display: inline-block; width: .55rem; height: .55rem; margin: 0 .6rem .2rem 0; border-radius: var(--pill); background: var(--signal); }
.side-index__subtitle { font-size: var(--interface-size); }
.side-index__identity { margin: var(--space-sm) 0 var(--space-lg); font-size: var(--interface-size); color: var(--quiet-ink); }
.side-index__group + .side-index__group { margin-top: var(--space-md); }
.side-index__heading { margin: 0 0 var(--space-xs); color: var(--quiet-ink); font-size: var(--interface-size); font-weight: 600; line-height: 1.4; }
.side-index__link { display: flex; align-items: center; min-height: 3rem; margin-block: .15rem; padding: .5rem .85rem; color: var(--ink); font-size: var(--interface-size); line-height: 1.4; text-decoration: none; border: 1px solid transparent; border-radius: var(--pill); }
.side-index__link:hover { color: var(--hover-ink); background: var(--surface); }
.side-index__link[aria-current="page"] { background: var(--ink); color: var(--paper); }
.side-index__toggle, .side-index__opener { display: none; }

.chapter { min-width: 0; padding-top: var(--space-lg); }
.chapter__header { margin-bottom: var(--space-lg); }
.chapter__eyebrow { display: inline-flex; align-items: center; margin: 0 0 var(--space-md); min-height: 2.25rem; padding-inline: 1rem; border: 1px solid var(--border-ink); border-radius: var(--pill); font-size: var(--interface-size); color: var(--quiet-ink); }
.chapter__title { margin: 0 0 var(--space-md); max-width: 15ch; font-size: clamp(2.75rem, 4.9vw, 4.625rem); line-height: 1.04; letter-spacing: -.055em; font-weight: 750; text-wrap: balance; }
.chapter--home .chapter__title { max-width: 16ch; }
.chapter__deck { max-width: 48ch; margin: 0; font-size: clamp(1.25rem, 1.7vw, 1.5rem); line-height: 1.55; color: var(--quiet-ink); }
.chapter__body { max-width: var(--measure); }
.chapter__opening { margin: 0 0 var(--space-xl); padding-top: var(--space-md); border-top: 1px solid var(--border-ink); }
.chapter__section { margin-block: var(--space-lg); scroll-margin-top: var(--space-md); }
.chapter__subhead { margin: 0 0 var(--space-sm); font-size: clamp(1.45rem, 2vw, 1.8rem); font-weight: 650; line-height: 1.25; letter-spacing: -.025em; text-wrap: pretty; }
.chapter__text { margin: 0 0 var(--space-sm); }
.chapter__section--answer { padding: var(--space-md) var(--space-lg); background: var(--surface); border-top: 1px solid var(--border-ink); border-bottom: 1px solid var(--border-ink); }
.chapter__section--answer .chapter__subhead::before { content: ""; display: inline-block; width: .5rem; height: .5rem; margin: 0 .55rem .2rem 0; border-radius: var(--pill); background: var(--signal); }
.chapter__section--urgent { padding: var(--space-md) var(--space-lg); border: 1px solid var(--border-ink); border-left: .25rem solid var(--crimson); border-radius: .3rem; }
.chapter__reference { display: inline-flex; align-items: center; justify-content: center; vertical-align: baseline; min-width: var(--tap); min-height: var(--tap); padding-inline: .5rem; border: 1px solid var(--border-ink); border-radius: var(--pill); font-size: var(--interface-size); line-height: 1; text-decoration: none; margin-inline-start: .2rem; }
.chapter__reference:hover { border-color: var(--hover-ink); }
.chapter__link { display: flex; align-items: center; justify-content: space-between; gap: var(--space-sm); width: fit-content; max-width: 100%; min-height: 3rem; margin-block: var(--space-xs); padding-block: .4rem; text-decoration: none; border-bottom: 1px solid var(--border-ink); }
.chapter__arrow { flex-shrink: 0; color: var(--link-ink); font-size: 1.3rem; }
.chapter__link:hover .chapter__arrow, .chapter__related:hover .chapter__arrow { color: var(--hover-ink); }
.chapter__recap { margin-top: var(--space-xl); padding-top: var(--space-md); border-top: 1px solid var(--border-ink); }
.chapter__related { display: flex; align-items: center; justify-content: space-between; gap: var(--space-md); min-height: 3.5rem; padding: var(--space-sm) var(--space-md); margin: var(--space-md) 0 var(--space-lg); border: 1px solid var(--border-ink); border-radius: var(--pill); text-decoration: none; }

.page-notes { padding-top: var(--space-lg); margin-top: var(--space-xl); border-top: 1px solid var(--border-ink); }
.page-notes__heading { font-size: 1.4rem; font-weight: 650; letter-spacing: -.02em; line-height: 1.3; margin: 0 0 var(--space-md); }
.page-notes__entry { margin-bottom: var(--space-md); scroll-margin-top: var(--space-md); }
.page-notes__source { display: flex; align-items: center; gap: var(--space-xs); min-height: var(--tap); padding-block: .5rem; font-size: var(--interface-size); line-height: 1.5; }
.page-notes__key { flex-shrink: 0; color: var(--ink); }
.page-notes__text { color: var(--quiet-ink); font-size: var(--interface-size); line-height: var(--reading-height); margin: 0; }

.handbook-footer { margin: var(--space-xl) 0 0; padding: var(--space-lg) 0 var(--space-lg); border-top: 1px solid var(--border-ink); max-width: var(--measure); }
.handbook-footer__text { margin: 0 0 var(--space-md); font-size: var(--interface-size); color: var(--quiet-ink); }
.handbook-footer__links { display: flex; flex-wrap: wrap; gap: var(--space-xs) var(--space-md); }
.handbook-footer__link { display: flex; align-items: center; min-height: 3rem; font-size: var(--interface-size); padding-block: .45rem; }

.wordbook__controls { margin-bottom: var(--space-lg); padding: var(--space-md); background: var(--surface); border-radius: .5rem; }
.wordbook__label { display: block; font-size: var(--interface-size); font-weight: 650; margin-bottom: var(--space-xs); }
.wordbook__search { display: flex; gap: var(--space-xs); }
.wordbook__input { width: 100%; min-width: 0; min-height: 3rem; border: 1px solid var(--border-ink); border-radius: var(--pill); background: var(--paper); color: var(--ink); padding: .6rem 1rem; font-size: var(--interface-size); }
.wordbook__clear { flex-shrink: 0; min-width: var(--tap); min-height: 3rem; padding: .6rem 1rem; border: 1px solid var(--border-ink); border-radius: var(--pill); background: var(--ink); color: var(--paper); cursor: pointer; font-size: var(--interface-size); }
.wordbook__clear:hover { background: var(--hover-ink); }
.wordbook__help, .wordbook__status { font-size: var(--interface-size); color: var(--quiet-ink); margin: var(--space-xs) 0 0; }
.wordbook__entry { padding-block: var(--space-md); border-bottom: 1px solid var(--border-ink); }
.wordbook__term { margin: 0 0 var(--space-xs); font-size: 1.6rem; line-height: 1.3; letter-spacing: -.025em; }
.wordbook__empty { margin-block: var(--space-md); }

@media (min-width: 62rem) and (max-height: 52rem) {
  .side-index__identity { margin-bottom: var(--space-md); }
  .side-index__group + .side-index__group { margin-top: var(--space-sm); }
}

@media (max-width: 61.99rem) {
  .handbook__layout { grid-template-columns: minmax(0, 1fr); gap: 0; padding: var(--space-md) clamp(1.125rem, 5vw, 2.5rem) 0; max-width: 48rem; }
  .side-index { position: static; max-height: none; overflow: visible; padding: 0 0 var(--space-sm); border-right: 0; border-bottom: 1px solid var(--border-ink); }
  .side-index__brand { flex-direction: row; align-items: center; justify-content: flex-start; flex-wrap: wrap; column-gap: var(--space-sm); }
  .side-index__name { font-size: 1.6rem; }
  .side-index__subtitle { line-height: 1.4; }
  .side-index__identity { margin: .2rem 0 var(--space-xs); }
  .side-index__menu { position: relative; }
  .side-index__toggle { appearance: none; display: grid; place-items: center; position: absolute; top: .15rem; right: .9rem; width: var(--tap); height: var(--tap); margin: 0; border: 0; border-radius: var(--pill); background: transparent; color: var(--ink); cursor: pointer; }
  .side-index__toggle::before { content: "+"; font-size: 1.3rem; line-height: 1; }
  .side-index__toggle:checked::before { content: "−"; }
  .side-index__opener { display: flex; justify-content: space-between; align-items: center; min-height: 3rem; width: 100%; cursor: pointer; padding: .6rem 4rem .6rem .9rem; border: 1px solid var(--border-ink); border-radius: var(--pill); font-size: var(--interface-size); }
  .side-index__opener:hover { color: var(--hover-ink); }
  .side-index__toggle:focus-visible + .side-index__opener { outline: .2rem solid var(--ink); outline-offset: .2rem; }
  .side-index__toggle:not(:checked) ~ .side-index__navigation { display: none; }
  .side-index__navigation { padding: var(--space-md) 0 var(--space-xs); }
  .chapter { padding-top: var(--space-lg); }
  .chapter__title { font-size: clamp(2.625rem, 7.5vw, 4rem); max-width: 18ch; }
  .chapter--home .chapter__title { max-width: 18ch; }
}

@media (max-width: 30rem) {
  .chapter__section--answer, .chapter__section--urgent { padding: var(--space-md); }
  .chapter__related { border-radius: 1.75rem; }
  .chapter__opening { margin-bottom: var(--space-lg); }
  .chapter__header { margin-bottom: var(--space-md); }
}

@media (prefers-reduced-motion: reduce) {
  *, *::before, *::after { scroll-behavior: auto !important; animation: none !important; transition: none !important; }
}

@media print {
  :root { --body-size: 1rem; }
  body { background: white; color: black; }
  .handbook__layout { display: block; padding: 0; }
  .side-index, .handbook__skip, .wordbook__controls, .handbook-footer__links { display: none; }
  .chapter { padding: 0; }
  .chapter__title { font-size: 2.5rem; }
  .chapter__body { max-width: none; }
  .chapter__section, .wordbook__entry { break-inside: avoid; }
  .wordbook__entry[hidden] { display: block !important; }
  .wordbook__empty { display: none !important; }
}