:root {
  --pb-bg: #f2f1eb;
  --pb-paper: #fffef9;
  --pb-ink: #171b18;
  --pb-muted: #626a63;
  --pb-quiet: #899089;
  --pb-line: #d9ddd8;
  --pb-accent: #166534;
  --pb-accent-soft: #e7f5ea;
  --pb-dark: #0c100d;
  --pb-comments-width: clamp(380px, 32vw, 480px);
}

html { max-width: 100%; overflow-x: clip; scroll-padding-top: 96px; }
body {
  min-width: 320px;
  max-width: 100%;
  overflow-x: clip;
  background: var(--pb-bg) !important;
  color: var(--pb-ink) !important;
  font-size: 17px;
  line-height: 1.76;
  text-rendering: optimizeLegibility;
  -webkit-font-smoothing: antialiased;
  transition: padding-right .24s ease;
}
body.pb-comments-open { padding-right: var(--pb-comments-width); }

.pb-reading-progress { position: fixed; inset: 0 0 auto; z-index: 50; height: 3px; background: transparent; }
.pb-reading-progress span { display: block; width: 0; height: 100%; background: var(--pb-accent); transition: width 80ms linear; }
.pb-coursebar { position: sticky; top: 0; z-index: 40; border-bottom: 1px solid rgba(255,255,255,.1); background: rgba(12,16,13,.94); color: white; backdrop-filter: blur(16px); }
.pb-coursebar-inner { width: min(calc(100% - 36px), 1180px); min-height: 62px; display: flex; align-items: center; justify-content: space-between; gap: 26px; margin-inline: auto; }
.pb-coursebar a { color: inherit !important; text-decoration: none !important; }
.pb-brand { font-size: .86rem; font-weight: 780; letter-spacing: -.03em; }
.pb-crumb { min-width: 0; display: flex; align-items: center; gap: 10px; color: #98a29a; font-size: .72rem; }
.pb-crumb-course { overflow: hidden; max-width: 380px; color: #dce2dd; text-overflow: ellipsis; white-space: nowrap; }
.pb-coursebar-actions { display: flex; gap: 18px; color: #9da69f; font-size: .7rem; white-space: nowrap; }
.pb-comments-toggle { appearance: none; padding: 0; border: 0; background: transparent; color: inherit; cursor: pointer; font: inherit; }
.pb-comments-toggle[aria-expanded="true"] { color: white; }
.pb-coursebar a:hover { color: white !important; }
.pb-comments-toggle:hover, .pb-comments-toggle:focus-visible { color: white; }

.page {
  width: min(1040px, calc(100% - 48px)) !important;
  margin-inline: auto !important;
  padding: clamp(48px, 7vw, 76px) 0 100px !important;
}
.page > .eyebrow, .guide-eyebrow { color: var(--pb-accent) !important; font-family: "SFMono-Regular", Consolas, monospace !important; font-size: .7rem !important; letter-spacing: .12em !important; }
.page > h1 {
  max-width: 960px !important;
  margin-top: 12px !important;
  color: var(--pb-ink) !important;
  font-family: ui-serif, Georgia, Cambria, "Times New Roman", serif !important;
  font-size: clamp(2.65rem, 6vw, 5.25rem) !important;
  font-weight: 610 !important;
  line-height: 1.02 !important;
  letter-spacing: -.055em !important;
}
.page > .lede {
  max-width: 820px !important;
  margin-top: 24px !important;
  color: #444c45 !important;
  font-size: clamp(1.12rem, 2.2vw, 1.36rem) !important;
  line-height: 1.7 !important;
}
.meta { gap: 8px !important; margin-top: 25px !important; }
.meta span, .meta p { margin: 0 !important; padding: 5px 10px !important; border: 1px solid var(--pb-line) !important; border-radius: 999px !important; background: rgba(255,255,255,.55) !important; color: var(--pb-muted) !important; font-size: .75rem !important; }
.rule { margin-block: 48px !important; background: var(--pb-line) !important; }

.page h2 { position: relative; margin-top: 78px !important; color: var(--pb-ink) !important; font-size: clamp(1.75rem, 3.7vw, 2.55rem) !important; letter-spacing: -.036em !important; }
.page h3 { color: var(--pb-ink) !important; font-size: 1.18rem !important; }
.page h2[id]::before { position: absolute; top: .2em; left: -28px; color: var(--pb-accent); content: ""; width: 12px; height: 2px; background: currentColor; }
.page p, .page li { color: #303731; }
.page strong { color: #151a16; }
.page a { color: var(--pb-accent); text-decoration-thickness: 1px; text-underline-offset: .18em; }
.page a:hover { color: #0f4f27; }
.page > p:not(.lede):not(.eyebrow),
.page > ul,
.page > ol,
.page > blockquote { max-width: 820px; }
.page > p:has(> .katex-display) { max-width: none; }
.page > p,
.page > ul,
.page > ol { text-wrap: pretty; }

.card, .quiz, .template, .step-card, .connection-item {
  border-color: var(--pb-line) !important;
  background: var(--pb-paper) !important;
  box-shadow: 0 12px 34px rgba(31,39,32,.065) !important;
}
.card, .quiz { border-radius: 14px !important; }
.idea { border-left-color: var(--pb-accent) !important; }
.warning, .pitfall { border-left-color: #a95d0b !important; background: #fff7e5 !important; }
.loop { gap: 10px !important; }
.loop article { min-height: 150px !important; border-color: var(--pb-line) !important; border-radius: 12px !important; background: var(--pb-paper) !important; }
.loop article::before { background: var(--pb-accent) !important; }
.checklist li::before { color: var(--pb-accent) !important; }

code { background: #e8e9e3 !important; color: #243128 !important; }
pre { position: relative; box-sizing: border-box; max-width: 100%; overflow-x: auto !important; padding: 42px 24px 24px !important; border: 1px solid #283029; border-radius: 12px !important; background: #111612 !important; box-shadow: 0 12px 32px rgba(12,16,13,.12); font-size: .84rem !important; line-height: 1.65 !important; tab-size: 2; white-space: pre !important; }
pre::before { position: absolute; top: 12px; left: 24px; color: #7f8a81; content: attr(data-language); font-family: "SFMono-Regular", Consolas, monospace; font-size: .58rem; font-weight: 720; letter-spacing: .1em; text-transform: uppercase; }
pre code { background: transparent !important; color: inherit !important; }
.pb-copy-code { position: absolute; top: 9px; right: 9px; z-index: 2; min-height: 28px; padding: 0 9px; border: 1px solid rgba(255,255,255,.17); border-radius: 6px; background: rgba(255,255,255,.07); color: #c7d0c9; cursor: pointer; font-size: .65rem; opacity: 0; transition: opacity .15s ease, background .15s ease; }
pre:hover .pb-copy-code, .pb-copy-code:focus-visible { opacity: 1; }
.pb-copy-code:hover { background: rgba(255,255,255,.14); }
.katex-display { max-width: 100%; overflow-x: auto; overflow-y: hidden; padding: 8px 0; }
.pb-math-fallback { padding: 0 .12em; border-radius: 3px; background: #f0eee7; text-decoration: underline dotted #8a8174; text-underline-offset: .18em; }

table { max-width: 100%; border-collapse: collapse; }
.pb-table-scroll { box-sizing: border-box; width: fit-content; max-width: 100%; margin: 22px 0; overflow-x: auto; contain: paint; border: 1px solid var(--pb-line); border-radius: 10px; background: var(--pb-paper); }
.pb-table-scroll table { display: table; width: max-content !important; min-width: 0; max-width: none; margin: 0 !important; overflow: visible !important; border: 0 !important; border-radius: 0 !important; background: transparent !important; }
th { background: #edf0eb; color: #384039; }
th, td { min-width: 120px; border-color: var(--pb-line) !important; }
.component-table { display: table; }

.guide-banner {
  width: auto !important;
  margin: -76px calc(50% - 50vw) 52px !important;
  padding: clamp(64px, 8vw, 104px) max(24px, calc((100vw - 1040px) / 2)) 58px !important;
  border-radius: 0 !important;
  background: var(--pb-dark) !important;
  color: white !important;
}
.guide-banner h1 { max-width: 850px; color: white !important; font-size: clamp(2.55rem, 6vw, 5rem) !important; line-height: 1.02 !important; }
.guide-banner .guide-lede { color: #aeb8b0 !important; }
.guide-meta span { border-color: rgba(255,255,255,.14) !important; background: rgba(255,255,255,.06) !important; color: #c7cec8 !important; }
.meta-icon { display: none; }
.mindset-banner::before { content: none !important; }
.mindset-banner { padding-left: 24px !important; }

.quiz button { border-color: var(--pb-line) !important; background: #f8f8f3 !important; color: var(--pb-ink) !important; }
.quiz button:hover, .quiz button:focus-visible, .quiz button[aria-pressed="true"] { border-color: var(--pb-accent) !important; background: var(--pb-accent-soft) !important; }

.source-outline-intro { max-width: 820px; color: var(--pb-muted) !important; }
.assignment-guide { margin: 72px 0 0; padding: 28px 0; border-block: 1px solid var(--pb-line); }
.assignment-guide-kicker { margin: 0 0 8px; color: var(--pb-accent) !important; font-family: "SFMono-Regular", Consolas, monospace; font-size: .65rem; font-weight: 760; letter-spacing: .1em; text-transform: uppercase; }
.assignment-guide h2 { margin-top: 0 !important; }
.assignment-guide-overview { max-width: 820px; color: var(--pb-muted) !important; font-size: 1.02rem; }
.assignment-guide-grid { display: grid; grid-template-columns: repeat(3, minmax(0, 1fr)); gap: 24px; margin-top: 28px; }
.assignment-guide-grid section { min-width: 0; }
.assignment-guide-grid h3 { margin: 0 0 10px; font-size: .9rem !important; }
.assignment-guide-grid ul { margin: 0; padding-left: 1.15rem; }
.assignment-guide-grid li { margin: 5px 0; font-size: .78rem; line-height: 1.65; }
.source-outline-notes, .source-gaps { margin: 24px 0; padding: 18px 0; border-block: 1px solid var(--pb-line); }
.source-outline-notes h3, .source-gaps h3 { margin: 0 0 10px; font-size: .98rem !important; }
.source-outline-notes ul, .source-gaps ul { margin-block: 0; }
.problem-outline { margin-top: 30px; border-top: 1px solid var(--pb-line); }
.problem-row { border-bottom: 1px solid var(--pb-line); }
.problem-row > summary { display: grid; grid-template-columns: 86px minmax(0, 1fr) minmax(120px, auto); gap: 14px; align-items: baseline; padding: 17px 2px; cursor: pointer; list-style: none; }
.problem-row > summary::-webkit-details-marker { display: none; }
.problem-row > summary::after { grid-column: 3; grid-row: 1; justify-self: end; color: var(--pb-accent); content: "+"; font-size: 1rem; }
.problem-row[open] > summary::after { content: "−"; }
.problem-number { color: var(--pb-accent); font-family: "SFMono-Regular", Consolas, monospace; font-size: .66rem; font-weight: 760; letter-spacing: .04em; }
.problem-row > summary strong { min-width: 0; font-size: .9rem; line-height: 1.45; }
.problem-topics { grid-column: 3; grid-row: 1; padding-right: 24px; color: var(--pb-quiet); font-size: .63rem; text-align: right; }
.problem-body { padding: 2px 2px 28px 84px; }
.problem-body > p:first-child { margin-top: 0; }
.problem-badges { display: flex; flex-wrap: wrap; gap: 7px; margin: 0 0 12px; }
.problem-badges span { padding: 3px 8px; border: 1px solid var(--pb-line); border-radius: 999px; color: var(--pb-muted); font-family: "SFMono-Regular", Consolas, monospace; font-size: .58rem; letter-spacing: .035em; }
.problem-badges .offline-ready { border-color: rgba(22, 101, 52, .25); background: var(--pb-accent-soft); color: var(--pb-accent); }
.problem-subparts { padding-left: 1.35rem; }
.problem-subsection { margin-top: 20px; }
.problem-subsection h4 { margin: 0 0 8px; color: var(--pb-muted); font-size: .76rem; letter-spacing: .04em; text-transform: uppercase; }
.problem-subsection ul { margin-block: 0; }
.problem-method { margin-top: 20px; padding: 14px 16px; border-left: 3px solid var(--pb-accent); background: rgba(22, 101, 52, .045); }
.problem-method strong { font-size: .74rem; letter-spacing: .04em; text-transform: uppercase; }
.problem-method p { margin: 5px 0 0; }
.problem-disclosure { margin-top: 16px; border: 1px solid var(--pb-line); border-radius: 10px; background: rgba(255,255,255,.28); overflow: clip; }
.problem-disclosure > summary { display: flex; align-items: center; justify-content: space-between; gap: 12px; padding: 12px 14px; color: var(--pb-muted); cursor: pointer; font-size: .76rem; font-weight: 720; list-style: none; }
.problem-disclosure > summary::-webkit-details-marker { display: none; }
.problem-disclosure > summary::after { color: var(--pb-accent); content: "+"; font-family: "SFMono-Regular", Consolas, monospace; }
.problem-disclosure[open] > summary::after { content: "−"; }
.problem-disclosure-body { padding: 2px 16px 16px; border-top: 1px solid var(--pb-line); }
.problem-disclosure-body > :first-child { margin-top: 14px; }
.solution-disclosure { border-left: 3px solid var(--pb-accent); }
.problem-visual-note { padding: 14px 16px; border-left: 3px solid var(--pb-line); background: rgba(255,255,255,.24); }
.problem-source-note { margin: 18px 0 0; padding-left: 12px; border-left: 2px solid var(--pb-line); color: var(--pb-muted) !important; font-size: .72rem; }
.problem-source { margin: 18px 0 0; color: var(--pb-quiet) !important; font-size: .68rem; }
.problem-source code, .source-outline code, .page li code { white-space: normal; overflow-wrap: anywhere; word-break: break-word; }
.page pre > code { white-space: inherit; overflow-wrap: normal; word-break: normal; }

.pb-toc { position: fixed; top: 94px; left: calc(50% + 560px); z-index: 20; width: 210px; max-height: calc(100vh - 120px); overflow: auto; padding-left: 18px; border-left: 1px solid var(--pb-line); }
.pb-toc-label { margin: 0 0 12px; color: var(--pb-quiet); font-family: "SFMono-Regular", Consolas, monospace; font-size: .62rem; letter-spacing: .1em; text-transform: uppercase; }
.pb-toc a { display: block; padding: 5px 0; color: var(--pb-quiet); font-size: .7rem; line-height: 1.4; text-decoration: none; }
.pb-toc a[data-level="3"] { padding-left: 12px; }
.pb-toc a:hover, .pb-toc a.is-active { color: var(--pb-accent); }

.pb-pager { display: grid; grid-template-columns: repeat(2, minmax(0, 1fr)); gap: 12px; margin-top: 72px; padding-top: 24px; border-top: 1px solid var(--pb-line); }
.pb-pager-link { min-height: 94px; display: flex; flex-direction: column; justify-content: center; padding: 17px 19px; border: 1px solid var(--pb-line); border-radius: 10px; background: var(--pb-paper); text-decoration: none !important; }
.pb-pager-link:last-child { text-align: right; }
.pb-pager-label { color: var(--pb-quiet); font-family: "SFMono-Regular", Consolas, monospace; font-size: .61rem; letter-spacing: .08em; text-transform: uppercase; }
.pb-pager-title { margin-top: 5px; color: var(--pb-ink); font-size: .83rem; font-weight: 670; }
.pb-pager-spacer { min-height: 1px; }
.pb-ready .page > .nav { display: none !important; }

.pb-comments-drawer {
  position: fixed;
  inset: 0 0 0 auto;
  z-index: 70;
  box-sizing: border-box;
  width: var(--pb-comments-width);
  display: flex;
  flex-direction: column;
  border-left: 1px solid var(--pb-line);
  background: #fbfaf6;
  box-shadow: -18px 0 44px rgba(12,16,13,.08);
  color: var(--pb-ink);
  transform: translateX(100%);
  visibility: hidden;
  transition: transform .24s ease, visibility 0s linear .24s;
}
.pb-comments-open .pb-comments-drawer { transform: translateX(0); visibility: visible; transition-delay: 0s; }
.pb-comments-drawer[aria-hidden="true"] { display: none; }
.pb-comments-drawer-header { min-height: 92px; display: flex; align-items: center; justify-content: space-between; gap: 18px; padding: 18px 22px; border-bottom: 1px solid var(--pb-line); background: rgba(255,254,249,.9); backdrop-filter: blur(16px); }
.pb-comments-drawer-header h2 { margin: 0; font-family: ui-serif, Georgia, Cambria, "Times New Roman", serif; font-size: 1.38rem; line-height: 1.15; letter-spacing: -.03em; }
.pb-comments-kicker { margin: 0 0 9px; color: var(--pb-accent) !important; font-family: "SFMono-Regular", Consolas, monospace; font-size: .64rem; font-weight: 760; letter-spacing: .11em; text-transform: uppercase; }
.pb-comments-close { flex: 0 0 auto; min-height: 34px; padding: 0 12px; border: 1px solid var(--pb-line); border-radius: 999px; background: var(--pb-paper); color: var(--pb-muted); cursor: pointer; font-size: .7rem; }
.pb-comments-close:hover, .pb-comments-close:focus-visible { border-color: var(--pb-accent); color: var(--pb-accent); }
.pb-comments-drawer-body { min-height: 0; flex: 1; overflow-y: auto; overscroll-behavior: contain; padding: 20px 22px 32px; }
.pb-comments-intro { margin: 0 0 18px; color: var(--pb-muted); font-size: .78rem; line-height: 1.65; }
.pb-comments-status { padding: 16px 18px; border: 1px solid var(--pb-line); border-radius: 10px; background: rgba(255,255,255,.38); color: var(--pb-muted); font-size: .78rem; }
.pb-comments-status a { color: var(--pb-accent); }
.pb-comments-host, .giscus, .giscus-frame { width: 100%; }
.giscus-frame { color-scheme: light; }
.pb-comments-open .pb-toc { opacity: 0; pointer-events: none; }

@media (max-width: 1520px) { .pb-toc { display: none; } }
@media (max-width: 1080px) {
  body.pb-comments-open { padding-right: 0; overflow: hidden; }
  .pb-comments-drawer { width: 100%; }
}
@media (max-width: 900px) {
  .page { width: min(100% - 40px, 1040px) !important; }
  .problem-row > summary { grid-template-columns: 74px minmax(0, 1fr) minmax(110px, auto); }
  .problem-body { padding-left: 64px; }
}
@media (max-width: 720px) {
  .pb-coursebar-inner { min-height: 56px; }
  .pb-crumb-course, .pb-coursebar-actions a:last-child { display: none; }
  .page { width: min(calc(100% - 32px), 1040px) !important; padding-top: 40px !important; }
  .page h2[id]::before { display: none; }
  .guide-banner { margin-top: -40px !important; padding-inline: 16px !important; }
  .loop { grid-template-columns: 1fr !important; }
  .pb-pager { grid-template-columns: 1fr; }
  .pb-pager-link:last-child { text-align: left; }
  .pb-comments-drawer-header { min-height: 78px; padding: 14px 16px; }
  .pb-comments-drawer-body { padding: 18px 16px 28px; }
  .pb-table-scroll { display: block; box-sizing: border-box; width: 100%; min-width: 0; contain: paint; }
  .component-table { display: block; }
  .pb-copy-code { opacity: 1; }
  pre { padding: 38px 18px 20px !important; font-size: .78rem !important; }
  pre::before { top: 11px; left: 18px; }
  .assignment-guide-grid { grid-template-columns: 1fr; gap: 12px; }
  .problem-row > summary { grid-template-columns: 68px minmax(0, 1fr) 18px; gap: 8px 10px; }
  .problem-number { grid-column: 1; grid-row: 1 / span 2; }
  .problem-row > summary strong { grid-column: 2; grid-row: 1; }
  .problem-topics { grid-column: 2; grid-row: 2; padding-right: 0; text-align: left; }
  .problem-row > summary::after { grid-column: 3; grid-row: 1 / span 2; align-self: center; }
  .problem-body { padding-left: 0; }
}
@media print {
  .pb-reading-progress, .pb-coursebar, .pb-toc, .pb-copy-code, .pb-pager, .pb-comments-drawer { display: none !important; }
  body { background: white !important; }
  .page { width: 100% !important; padding: 0 !important; }
  .pb-table-scroll { overflow: visible; border: 0; }
  .pb-table-scroll table { width: 100% !important; }
}
@media (prefers-reduced-motion: reduce) { html { scroll-behavior: auto; } * { transition-duration: .01ms !important; } }