:root {
  --white: #fff;
  --off: #fbfcff;
  --paper: #f5f7fb;
  --navy: #0d1b3d;
  --navy-2: #142851;
  --graphite: #33373d;
  --muted: #66738a;
  --blue: #0066ff;
  --blue-2: #2c7cff;
  --blue-wash: #edf4ff;
  --line: rgba(13, 27, 61, .12);
  --line-strong: rgba(13, 27, 61, .22);
  --font-serif: Georgia, "Times New Roman", serif;
  --font-body: "Helvetica Neue", Helvetica, Arial, sans-serif;
  --font-mono: ui-monospace, "SF Mono", Menlo, Consolas, monospace;
  --prose: 820px;
  --shadow: 0 28px 90px rgba(13, 27, 61, .10);
  --ease: cubic-bezier(.2, .8, .2, 1);
}

* { box-sizing: border-box; }
html { scroll-behavior: smooth; }
body {
  margin: 0;
  color: var(--navy);
  background: var(--paper);
  font: 400 16px/1.65 var(--font-body);
  text-rendering: optimizeLegibility;
}
img, svg { max-width: 100%; height: auto; }
a { color: var(--blue); text-decoration: none; }
a:hover { text-decoration: underline; }
::selection { background: var(--blue); color: #fff; }

.chrome {
  position: sticky;
  top: 0;
  z-index: 500;
}
.review-banner {
  background: var(--navy);
  color: #fff;
  text-align: center;
  padding: .65rem 1.2rem;
  font: 500 .68rem/1.35 var(--font-mono);
  letter-spacing: .14em;
  text-transform: uppercase;
}
.review-banner em {
  color: var(--blue-2);
  font-style: normal;
}
.site-header {
  background: rgba(255, 255, 255, .95);
  border-bottom: 1px solid var(--line);
  backdrop-filter: blur(14px);
}
.header-inner {
  max-width: var(--prose);
  margin: 0 auto;
  min-height: 72px;
  padding: .6rem 1.25rem;
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 1.25rem;
}
.brand { display: block; flex: none; }
.brand img { display: block; width: 168px; height: auto; }
.primary-nav {
  display: flex;
  align-items: center;
  gap: 1.2rem;
}
.primary-nav a {
  font: 500 .62rem/1 var(--font-mono);
  letter-spacing: .03em;
  text-transform: uppercase;
  color: var(--navy);
  text-decoration: none;
}
.primary-nav a:hover,
.primary-nav a[aria-current="page"] { color: var(--blue); }
.primary-nav a[aria-current="page"] { text-decoration: none; border-bottom: 1px solid var(--blue); padding-bottom: .2rem; }

main {
  max-width: var(--prose);
  margin: 0 auto;
  padding: 2.4rem 1.25rem 4.5rem;
}
.eyebrow {
  margin: 0 0 .9rem;
  color: var(--blue);
  font: 500 .68rem/1.35 var(--font-mono);
  letter-spacing: .14em;
  text-transform: uppercase;
}
h1 {
  margin: 0 0 1.1rem;
  font: 500 clamp(2.4rem, 5vw, 3.6rem)/.95 var(--font-serif);
  letter-spacing: -.04em;
}
h1 em { color: var(--blue); font-style: italic; font-weight: 500; }
.lede {
  color: var(--graphite);
  font-size: 1.05rem;
  max-width: 68ch;
}
.lede p { margin: 0 0 .85rem; }

.toc {
  margin: 2rem 0 2.4rem;
  padding: 1.35rem 1.4rem 1.2rem;
  background: var(--white);
  border: 1px solid var(--line);
}
.toc .eyebrow { margin-bottom: .85rem; }
.toc ol {
  margin: 0;
  padding: 0;
  list-style: none;
  display: grid;
  gap: .45rem .8rem;
}
.toc a {
  color: var(--navy);
  font: 500 .92rem/1.4 var(--font-body);
  text-decoration: none;
  display: flex;
  gap: .7rem;
}
.toc a:hover { color: var(--blue); }
.toc .num {
  color: var(--blue);
  font: 500 .68rem/1.6 var(--font-mono);
  letter-spacing: .06em;
  min-width: 1.6rem;
}

.prose {
  background: var(--white);
  border: 1px solid var(--line);
  padding: 2rem 1.6rem 2.4rem;
}
.prose > :first-child { margin-top: 0; }
.prose h2 {
  margin: 2.6rem 0 .9rem;
  padding-top: 1.6rem;
  border-top: 1px solid var(--line);
  font: 500 clamp(1.7rem, 3.2vw, 2.35rem)/1.12 var(--font-serif);
  letter-spacing: -.03em;
  scroll-margin-top: 8.5rem;
}
.prose h2:first-child { border-top: 0; padding-top: 0; margin-top: 0; }
.prose h3 {
  margin: 1.8rem 0 .7rem;
  font: 600 1.05rem/1.35 var(--font-body);
  letter-spacing: -.01em;
  scroll-margin-top: 8.5rem;
}
.prose p { margin: 0 0 1rem; }
.prose p.label { margin: 1.15rem 0 .3rem; }
.prose h2 + p.label, .prose figure.diagram + p.label { margin-top: .15rem; }
.prose ul ul, .prose ol ul, .prose ul ol { margin: .3rem 0 .15rem; }
.prose .check-list { padding-left: .15rem; }

.prose ul, .prose ol { margin: 0 0 1.1rem; padding-left: 1.2rem; }
.prose li { margin: .28rem 0; }
.prose li::marker { color: var(--blue); }
.prose strong { font-weight: 700; }
.prose hr {
  border: 0;
  border-top: 1px solid var(--line);
  margin: 2rem 0;
}
.prose code {
  font: 500 .82em/1.4 var(--font-mono);
  background: var(--blue-wash);
  color: var(--navy);
  padding: .08em .32em;
}
.prose blockquote {
  margin: 1.1rem 0 1.3rem;
  padding: 1rem 1.15rem;
  border-left: 3px solid var(--blue);
  background: var(--paper);
  color: var(--navy-2);
}
.prose blockquote p { margin: 0 0 .7rem; }
.prose blockquote p:last-child { margin-bottom: 0; }
.prose table {
  width: 100%;
  border-collapse: collapse;
  margin: 0 0 1.3rem;
  font-size: .92rem;
}
.prose th, .prose td {
  border: 1px solid var(--line);
  padding: .55rem .7rem;
  text-align: left;
  vertical-align: top;
}
.prose th {
  background: var(--paper);
  font: 500 .68rem/1.35 var(--font-mono);
  letter-spacing: .06em;
  text-transform: uppercase;
  color: var(--navy);
}
.prose td { color: var(--navy-2); }
.prose .check {
  list-style: none;
  margin-left: -.2rem;
}
.prose .check input {
  accent-color: var(--blue);
  margin-right: .45rem;
  transform: translateY(1px);
}

figure.diagram {
  margin: 1.1rem -1.6rem 1.5rem;
  background: var(--paper);
  border-top: 1px solid var(--line);
  border-bottom: 1px solid var(--line);
}
figure.diagram img {
  display: block;
  width: 100%;
  height: auto;
  background: var(--white);
}
figure.diagram figcaption {
  margin: 0;
  padding: .55rem 1.6rem .7rem;
  color: var(--muted);
  font: 500 .62rem/1.4 var(--font-mono);
  letter-spacing: .08em;
  text-transform: uppercase;
}

.gallery {
  display: grid;
  gap: 1.4rem;
}
.gallery figure {
  margin: 0;
  background: var(--white);
  border: 1px solid var(--line);
}
.gallery img { display: block; width: 100%; }
.gallery figcaption {
  padding: .7rem 1rem .85rem;
  color: var(--muted);
  font: 500 .62rem/1.4 var(--font-mono);
  letter-spacing: .08em;
  text-transform: uppercase;
}
.gallery h2 {
  margin: 0 0 .35rem;
  padding: 1rem 1rem 0;
  font: 500 1.35rem/1.15 var(--font-serif);
}

.site-footer {
  max-width: var(--prose);
  margin: 0 auto;
  padding: 0 1.25rem 3rem;
  color: var(--muted);
  font: 500 .62rem/1.5 var(--font-mono);
  letter-spacing: .08em;
  text-transform: uppercase;
}
.site-footer a { color: var(--muted); }

@media (max-width: 640px) {
  .brand img { width: 132px; }
  .header-inner { min-height: 64px; gap: .8rem; }
  .primary-nav { gap: .75rem; }
  .prose { padding: 1.4rem 1rem 1.8rem; }
  figure.diagram { margin-left: -1rem; margin-right: -1rem; }
  figure.diagram figcaption { padding-inline: 1rem; }
}