:root { --practice-ink: #20364a; --practice-accent: #236c75; }
body { color: #243441; line-height: 1.55; }
h1, h2, h3 { color: var(--practice-ink); }
h1 { font-weight: 650; }
h2 { margin-top: 1.8rem; }
a { color: #146477; }
.navbar { border-bottom: 3px solid var(--practice-accent); }
/* Unavailable navigation entries use #part-three or #argument-c.
   These rules disable pointer interaction; the matching include-after-body
   script supplies aria-disabled and removes the links from the tab order.
   Hover and focus retain the same colour. The navbar and sidebar colours
   retain AA contrast. Only navigation is affected, not an in-page contents
   list. This is the plain-CSS twin of the book site's styles.scss rule. */
.navbar .navbar-nav .nav-link[href$="#part-three"],
.navbar .navbar-nav .nav-link[href$="#part-three"]:hover,
.navbar .navbar-nav .nav-link[href$="#part-three"]:focus,
.navbar .navbar-nav .nav-link[href$="#part-three"].active,
.navbar .navbar-nav .nav-link[href$="#argument-c"],
.navbar .navbar-nav .nav-link[href$="#argument-c"]:hover,
.navbar .navbar-nav .nav-link[href$="#argument-c"]:focus,
.navbar .navbar-nav .nav-link[href$="#argument-c"].active {
  color: #d9e5e6;
  pointer-events: none;
  cursor: default;
}
.sidebar-navigation a[href$="#part-three"],
.sidebar-navigation a[href$="#part-three"]:hover,
.sidebar-navigation a[href$="#part-three"]:focus,
.sidebar-navigation a[href$="#argument-c"],
.sidebar-navigation a[href$="#argument-c"]:hover,
.sidebar-navigation a[href$="#argument-c"]:focus {
  color: #64717a;
  pointer-events: none;
  cursor: default;
}
#quarto-sidebar { border-right: 1px solid #d3dee1; }
#quarto-sidebar .sidebar-item-text { line-height: 1.35; }
main { max-width: 940px; }
table { font-size: .95rem; }
.exercise-cell { margin: 1rem 0; }
.exercise-editor-header { flex-wrap: wrap; gap: .5rem; }
.exercise-cell .cm-editor { border: 1px solid #b9c8ce; border-radius: 5px; }
details { margin: .8rem 0; }
summary { cursor: pointer; color: var(--practice-ink); font-weight: 600; padding: .4rem 0; }
summary:focus-visible { outline: 3px solid #c17c21; outline-offset: 2px; }
.qmsbr-workspace { padding: 1.2rem; border: 1px solid #bbcdd1; border-radius: 8px; background: #f5f9fa; }
.qmsbr-workspace label { display: block; font-weight: 600; margin-top: .7rem; }
.qmsbr-workspace textarea { width: 100%; padding: .7rem; border: 1px solid #91aab3; border-radius: 4px; background: white; }
.qmsbr-code { min-height: 12rem; font: .91rem/1.55 Consolas, monospace; tab-size: 2; }
.qmsbr-notes { min-height: 4rem; }
.qmsbr-controls { display: flex; flex-wrap: wrap; gap: .6rem; margin: .8rem 0; align-items: center; }
.qmsbr-workspace button { padding: .4rem .75rem; border: 1px solid #698a96; border-radius: 4px; background: #fff; color: #20364a; }
.qmsbr-workspace button[data-action="run"] { background: #236c75; color: white; }
.qmsbr-workspace button:disabled { opacity: .55; }
.qmsbr-workspace :focus-visible { outline: 3px solid #c17c21; outline-offset: 2px; }
.qmsbr-status { font-size: .92rem; }
.qmsbr-output, .qmsbr-preview { white-space: pre-wrap; overflow-wrap: anywhere; max-height: 36rem; overflow: auto; background: white; border: 1px solid #cfdbdf; padding: .8rem; }
.qmsbr-plots canvas { width: 100%; height: auto; max-width: 720px; }
.qmsbr-note { font-size: .93rem; }
.qmsbr-fallback { border-left: 4px solid #b4822c; padding: .7rem 1rem; margin: 1rem 0; background: #fffaef; }
.qmsbr-first-time { border-left: 4px solid var(--practice-accent); padding: .7rem 1.1rem; margin: 1.2rem 0; background: #f2f8f9; }
.qmsbr-first-time > p:first-child { font-weight: 600; margin-bottom: .4rem; }
.qmsbr-first-time ol { margin-bottom: .3rem; }
.qmsbr-first-time li { margin: .25rem 0; }
.qmsbr-runtime-unavailable > :not(.qmsbr-fallback),
.qmsbr-engine-failed .exercise-loading-indicator { display: none !important; }
@media (max-width: 600px) {
  .qmsbr-workspace { padding: .7rem; }
  .qmsbr-code { font-size: .85rem; }
  table { font-size: .88rem; }
}
@media print {
  .qmsbr-controls, .qmsbr-workspace input, .qmsbr-workspace button, .exercise-loading-indicator { display: none !important; }
  .qmsbr-output { max-height: none; overflow: visible; }
  .qmsbr-workspace { background: white; }
  .exercise-cell { display: none; }
}
/* The navbar is pinned, so anchors land below it. */
html { scroll-padding-top: 4.5rem; }
.navbar { box-shadow: 0 2px 18px rgba(13, 43, 62, .13); }