:root {
  --navy-950: #061a2b;
  --navy-900: #0b2d4d;
  --navy-800: #123f68;
  --blue-700: #155eaa;
  --blue-600: #1d6fc2;
  --blue-100: #dbeeff;
  --blue-050: #eff7ff;
  --ink-900: #15202b;
  --ink-700: #344454;
  --ink-600: #51606e;
  --line: #ccd7e1;
  --surface: #ffffff;
  --surface-alt: #f4f7fa;
  --success: #17633b;
  --warning: #8a5300;
  --danger: #9d2b2b;
  --focus: #ffbf47;
  --max-width: 74rem;
  --article-width: 48rem;
  --radius-sm: .45rem;
  --radius-md: .8rem;
  --radius-lg: 1.2rem;
  --shadow-sm: 0 .25rem .8rem rgba(6, 26, 43, .09);
  --shadow-md: 0 .8rem 2rem rgba(6, 26, 43, .12);
  --space-1: .35rem;
  --space-2: .65rem;
  --space-3: 1rem;
  --space-4: 1.5rem;
  --space-5: 2rem;
  --space-6: 3rem;
  --space-7: 4.5rem;
  --header-height: 4.5rem;
}

*,
*::before,
*::after { box-sizing: border-box; }

html {
  scroll-behavior: smooth;
  scroll-padding-top: calc(var(--header-height) + 1rem);
}

body {
  margin: 0;
  background: var(--surface);
  color: var(--ink-900);
  font-family: Inter, ui-sans-serif, system-ui, -apple-system, BlinkMacSystemFont, "Segoe UI", sans-serif;
  font-size: 1rem;
  line-height: 1.65;
  text-rendering: optimizeLegibility;
}

body,
button,
input,
textarea { font: inherit; }

a { color: var(--blue-700); text-underline-offset: .18em; text-decoration-thickness: .09em; }
a:hover { color: var(--navy-900); }
a:focus-visible,
button:focus-visible,
summary:focus-visible,
input:focus-visible,
textarea:focus-visible {
  outline: .2rem solid var(--focus);
  outline-offset: .2rem;
}

img,
svg,
video { max-width: 100%; }

h1,
h2,
h3 {
  color: var(--navy-950);
  font-weight: 760;
  line-height: 1.15;
  letter-spacing: -.025em;
  text-wrap: balance;
}

h1 { font-size: clamp(2.25rem, 6vw, 4.5rem); margin: 0 0 var(--space-4); }
h2 { font-size: clamp(1.65rem, 3vw, 2.55rem); margin: 0 0 var(--space-3); }
h3 { font-size: 1.22rem; margin: 0 0 var(--space-2); }
p { margin: 0 0 var(--space-3); }
ul, ol { margin: 0 0 var(--space-4); padding-left: 1.25rem; }
li + li { margin-top: .45rem; }

.container { width: min(calc(100% - 2rem), var(--max-width)); margin-inline: auto; }
.narrow { max-width: var(--article-width); }
.sr-only {
  position: absolute;
  width: 1px;
  height: 1px;
  padding: 0;
  margin: -1px;
  overflow: hidden;
  clip: rect(0, 0, 0, 0);
  white-space: nowrap;
  border: 0;
}
.skip-link {
  position: fixed;
  left: 1rem;
  top: -8rem;
  z-index: 1000;
  background: var(--focus);
  color: var(--navy-950);
  padding: .75rem 1rem;
  border-radius: var(--radius-sm);
  font-weight: 800;
}
.skip-link:focus { top: 1rem; }

.site-header {
  position: sticky;
  top: 0;
  z-index: 100;
  min-height: var(--header-height);
  background: rgba(255,255,255,.97);
  border-bottom: 1px solid var(--line);
}
.header-inner { min-height: var(--header-height); display: flex; align-items: center; justify-content: space-between; gap: var(--space-3); }
.brand { display: inline-flex; align-items: center; gap: .7rem; color: var(--navy-950); text-decoration: none; font-weight: 800; }
.brand-mark {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  min-width: 3.3rem;
  min-height: 2.2rem;
  padding-inline: .55rem;
  border: 2px solid var(--blue-700);
  border-radius: var(--radius-sm);
  color: var(--blue-700);
  font-size: .72rem;
  letter-spacing: .08em;
}
.brand-name { font-size: 1rem; }
.desktop-nav { display: none; align-items: center; gap: 1.2rem; }
.desktop-nav > a:not(.button) { color: var(--ink-700); text-decoration: none; font-weight: 680; font-size: .93rem; }
.desktop-nav > a[aria-current="page"]:not(.button) { color: var(--blue-700); text-decoration: underline; text-decoration-thickness: .16rem; text-underline-offset: .42rem; }

.mobile-nav { position: relative; }
.mobile-nav summary {
  cursor: pointer;
  list-style: none;
  border: 1px solid var(--line);
  border-radius: var(--radius-sm);
  padding: .55rem .8rem;
  color: var(--navy-950);
  font-weight: 750;
}
.mobile-nav summary::-webkit-details-marker { display: none; }
.mobile-nav[open] nav {
  position: absolute;
  right: 0;
  top: calc(100% + .7rem);
  width: min(19rem, calc(100vw - 2rem));
  display: grid;
  gap: .25rem;
  padding: .8rem;
  background: var(--surface);
  border: 1px solid var(--line);
  border-radius: var(--radius-md);
  box-shadow: var(--shadow-md);
}
.mobile-nav nav > a:not(.button) {
  display: block;
  padding: .65rem .7rem;
  border-radius: var(--radius-sm);
  color: var(--ink-900);
  font-weight: 680;
  text-decoration: none;
}
.mobile-nav nav > a[aria-current="page"] { background: var(--blue-050); color: var(--blue-700); }
.mobile-cta { margin-top: .4rem; }

.button {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  gap: .35rem;
  min-height: 2.85rem;
  padding: .7rem 1.05rem;
  border: 2px solid transparent;
  border-radius: var(--radius-sm);
  font-weight: 800;
  text-decoration: none;
  line-height: 1.2;
  transition: transform .15s ease, background-color .15s ease, border-color .15s ease;
}
.button:hover { transform: translateY(-1px); }
.button-primary { background: var(--blue-700); color: #fff; }
.button-primary:hover { background: var(--navy-800); color: #fff; }
.button-secondary { background: var(--surface); border-color: var(--blue-700); color: var(--blue-700); }
.button-secondary:hover { background: var(--blue-050); color: var(--navy-900); }
.button-small { min-height: 2.45rem; padding: .55rem .8rem; font-size: .9rem; }
.button-row { display: flex; flex-wrap: wrap; gap: .8rem; margin-top: var(--space-4); }
.text-link { display: inline-block; font-weight: 800; }
.microcopy { margin-top: var(--space-3); color: var(--ink-600); font-size: .9rem; }
.microcopy.light { color: #d7e5f2; }

.hero {
  padding: clamp(4rem, 9vw, 7.5rem) 0;
  background: var(--blue-050);
  border-bottom: 1px solid var(--line);
}
.hero-grid { display: grid; gap: var(--space-5); align-items: center; }
.hero .lead,
.page-hero .lead { font-size: clamp(1.15rem, 2vw, 1.42rem); color: var(--ink-700); max-width: 47rem; }
.hero-panel {
  background: var(--navy-900);
  color: #fff;
  border-radius: var(--radius-lg);
  padding: clamp(1.5rem, 4vw, 2.4rem);
  box-shadow: var(--shadow-md);
}
.hero-panel h2,
.hero-panel h3,
.hero-panel .kicker { color: #fff; }
.hero-panel .check-list li::before { color: #9ed0ff; }

.page-hero {
  padding: clamp(3.5rem, 8vw, 6rem) 0;
  background: var(--surface-alt);
  border-bottom: 1px solid var(--line);
}
.page-hero h1 { font-size: clamp(2.15rem, 5vw, 3.8rem); }
.error-hero { min-height: 55vh; display: grid; align-items: center; }

.eyebrow {
  margin-bottom: .8rem;
  color: var(--blue-700);
  font-size: .78rem;
  font-weight: 850;
  letter-spacing: .12em;
  text-transform: uppercase;
}
.kicker { font-weight: 800; letter-spacing: .04em; }
.answer { font-weight: 620; }
.section { padding: clamp(3.5rem, 8vw, 6rem) 0; }
.section-tinted { background: var(--surface-alt); border-block: 1px solid var(--line); }
.section-dark { background: var(--navy-950); color: #fff; }
.section-dark h2,
.section-dark .eyebrow { color: #fff; }
.section-heading { max-width: 46rem; margin-bottom: var(--space-5); }
.split { display: grid; gap: var(--space-5); align-items: start; }
.cta-panel { display: grid; gap: var(--space-4); align-items: center; }

.card-grid { display: grid; gap: 1rem; }
.card-grid.compact { grid-template-columns: repeat(auto-fit, minmax(13rem, 1fr)); }
.card {
  background: var(--surface);
  border: 1px solid var(--line);
  border-radius: var(--radius-md);
  padding: 1.4rem;
  box-shadow: var(--shadow-sm);
}
.card-number { color: var(--blue-700); font-weight: 850; letter-spacing: .08em; }

.callout {
  background: var(--blue-050);
  border-left: .35rem solid var(--blue-700);
  border-radius: var(--radius-sm);
  padding: 1.25rem 1.4rem;
}
.check-list,
.cross-list { list-style: none; padding-left: 0; }
.check-list li,
.cross-list li { position: relative; padding-left: 1.65rem; }
.check-list li::before,
.cross-list li::before { position: absolute; left: 0; font-weight: 900; }
.check-list li::before { content: "✓"; color: var(--success); }
.cross-list li::before { content: "—"; color: var(--danger); }

.step-list { list-style: none; padding: 0; display: grid; gap: 1rem; }
.step-list li { display: grid; grid-template-columns: 3rem 1fr; gap: 1rem; padding: 1.25rem; border: 1px solid var(--line); border-radius: var(--radius-md); }
.step-number { display: inline-flex; width: 2.4rem; height: 2.4rem; align-items: center; justify-content: center; background: var(--blue-700); color: white; border-radius: 50%; font-weight: 850; }

.faq-list { display: grid; gap: .8rem; }
.faq-list details {
  border: 1px solid var(--line);
  border-radius: var(--radius-md);
  padding: 0 1.1rem;
  background: var(--surface);
}
.faq-list summary { cursor: pointer; padding: 1rem 0; font-weight: 800; color: var(--navy-950); }
.faq-list details p { padding-bottom: 1rem; }

.content-grid { display: grid; gap: var(--space-5); padding-top: var(--space-6); padding-bottom: var(--space-7); }
.toc {
  align-self: start;
  background: var(--surface-alt);
  border: 1px solid var(--line);
  border-radius: var(--radius-md);
  padding: 1rem;
  overflow-x: auto;
}
.toc h2 { font-size: .9rem; text-transform: uppercase; letter-spacing: .09em; margin-bottom: .7rem; }
.toc nav { display: flex; gap: .5rem; min-width: max-content; }
.toc a {
  display: inline-block;
  padding: .45rem .7rem;
  background: var(--surface);
  border: 1px solid var(--line);
  border-radius: 999px;
  color: var(--ink-700);
  font-size: .88rem;
  font-weight: 700;
  text-decoration: none;
}
.article { min-width: 0; max-width: var(--article-width); }
.article section { margin-bottom: var(--space-6); scroll-margin-top: calc(var(--header-height) + 1rem); }
.article h2 { padding-top: .2rem; }
.article h3 { margin-top: var(--space-4); }

.process-grid { display: grid; gap: .9rem; margin: var(--space-4) 0; }
.process-grid > div { border: 1px solid var(--line); border-radius: var(--radius-md); padding: 1.1rem; }
.process-grid span { display: inline-flex; width: 2rem; height: 2rem; align-items: center; justify-content: center; background: var(--navy-900); color: white; border-radius: 50%; font-weight: 800; margin-bottom: .8rem; }

.comparison { display: grid; gap: 1rem; margin: var(--space-4) 0; }
.comparison > div { padding: 1.2rem; border: 1px solid var(--line); border-radius: var(--radius-md); background: var(--surface-alt); }

.table-wrap { overflow-x: auto; margin: var(--space-4) 0; border: 1px solid var(--line); border-radius: var(--radius-md); }
table { width: 100%; min-width: 42rem; border-collapse: collapse; background: var(--surface); }
th, td { padding: .9rem; text-align: left; vertical-align: top; border-bottom: 1px solid var(--line); }
th { background: var(--navy-900); color: white; font-size: .9rem; }
tr:last-child td { border-bottom: 0; }

.sources { padding: 1.3rem; background: var(--surface-alt); border: 1px solid var(--line); border-radius: var(--radius-md); }
.sources h2 { font-size: 1.35rem; }
.review-note { margin-top: var(--space-5); padding-top: var(--space-3); border-top: 1px solid var(--line); color: var(--ink-600); font-size: .9rem; }
.review-note p { margin-bottom: .25rem; }
.small { font-size: .88rem; color: var(--ink-600); }

.checklist-box { display: grid; gap: .8rem; padding: 1.2rem; background: var(--surface-alt); border: 1px solid var(--line); border-radius: var(--radius-md); }
.checklist-box label { display: grid; grid-template-columns: 1.25rem 1fr; gap: .7rem; align-items: start; cursor: pointer; }
.checklist-box input { width: 1.1rem; height: 1.1rem; margin-top: .3rem; accent-color: var(--blue-700); }

.tag-list { display: flex; flex-wrap: wrap; gap: .6rem; margin: var(--space-4) 0; }
.tag-list span { padding: .45rem .7rem; background: var(--blue-050); border: 1px solid #b9d8f4; border-radius: 999px; font-weight: 700; color: var(--navy-900); }

.code-example {
  margin: var(--space-4) 0;
  padding: 1.25rem;
  background: var(--navy-950);
  color: #fff;
  border-radius: var(--radius-md);
  font-family: ui-monospace, SFMono-Regular, Menlo, Consolas, monospace;
  font-size: .92rem;
}
.code-example p { margin-bottom: .35rem; }

.example-pair,
.before-after { display: grid; gap: 1rem; margin: var(--space-4) 0; }
.example-pair > div,
.before-after > div,
.example-stack article {
  padding: 1.2rem;
  border: 1px solid var(--line);
  border-radius: var(--radius-md);
  background: var(--surface-alt);
}
.before { border-left: .35rem solid var(--danger) !important; }
.after { border-left: .35rem solid var(--success) !important; }
.label { color: var(--ink-600); font-size: .8rem; font-weight: 850; letter-spacing: .08em; text-transform: uppercase; }
.formula { display: flex; flex-wrap: wrap; gap: .55rem; align-items: center; margin: var(--space-4) 0; }
.formula span { padding: .55rem .7rem; border-radius: var(--radius-sm); background: var(--blue-050); color: var(--navy-900); font-weight: 800; }
.formula span:nth-child(even) { background: transparent; padding-inline: .1rem; }

.status { display: inline-block; padding: .25rem .5rem; border-radius: 999px; font-size: .8rem; font-weight: 800; white-space: nowrap; }
.status-good { color: #0d4d2b; background: #dff3e8; }
.status-partial { color: #6c4300; background: #fff0c9; }
.status-gap { color: #7d2020; background: #fde2e2; }

.prompt-box,
.prompt-card {
  border: 1px solid var(--line);
  border-radius: var(--radius-md);
  padding: 1.25rem;
  background: var(--surface);
}
.prompt-grid { display: grid; gap: 1rem; }
.prompt-card { display: flex; flex-direction: column; align-items: flex-start; }
.prompt-card p { flex: 1; }
.copy-button {
  border: 2px solid var(--blue-700);
  background: var(--surface);
  color: var(--blue-700);
  border-radius: var(--radius-sm);
  min-height: 2.6rem;
  padding: .55rem .85rem;
  font-weight: 800;
  cursor: pointer;
}
.copy-button:hover { background: var(--blue-050); }
.copy-source { position: absolute; left: -9999px; width: 1px; height: 1px; }
.prompt-anatomy { display: grid; gap: .7rem; }
.prompt-anatomy p { padding: .9rem 1rem; background: var(--surface); border: 1px solid var(--line); border-radius: var(--radius-sm); margin: 0; }
.example-stack { display: grid; gap: .9rem; margin: var(--space-4) 0; }

.resource-list { font-size: 1.12rem; }

.site-footer { background: var(--navy-950); color: #dce7f1; padding-top: var(--space-6); }
.site-footer a { color: #b9dcff; }
.site-footer h2 { color: #fff; font-size: 1rem; letter-spacing: .05em; text-transform: uppercase; }
.footer-grid { display: grid; gap: var(--space-5); }
.footer-grid nav { display: grid; align-content: start; gap: .55rem; }
.footer-brand { color: #fff; font-size: 1.15rem; font-weight: 850; }
.footer-bottom { margin-top: var(--space-5); padding: 1rem 0; border-top: 1px solid #31506d; font-size: .85rem; }
.footer-bottom p { margin: 0; }

@media (min-width: 42rem) {
  .brand-name { font-size: 1.05rem; }
  .card-grid { grid-template-columns: repeat(2, 1fr); }
  .comparison,
  .example-pair,
  .before-after { grid-template-columns: repeat(2, minmax(0, 1fr)); }
  .process-grid { grid-template-columns: repeat(2, 1fr); }
  .prompt-grid { grid-template-columns: repeat(2, minmax(0, 1fr)); }
  .footer-grid { grid-template-columns: 1.4fr 1fr 1fr; }
}

@media (min-width: 60rem) {
  .desktop-nav { display: flex; }
  .mobile-nav { display: none; }
  .hero-grid { grid-template-columns: minmax(0, 1.35fr) minmax(18rem, .65fr); }
  .split { grid-template-columns: repeat(2, minmax(0, 1fr)); }
  .cta-panel { grid-template-columns: 1.4fr .6fr; }
  .card-grid { grid-template-columns: repeat(3, 1fr); }
  .content-grid { grid-template-columns: 14rem minmax(0, 1fr); align-items: start; }
  .toc { position: sticky; top: calc(var(--header-height) + 1rem); max-height: calc(100vh - var(--header-height) - 2rem); }
  .toc nav { display: grid; min-width: 0; }
  .toc a { border: 0; border-radius: var(--radius-sm); background: transparent; }
  .toc a:hover { background: var(--blue-050); }
  .process-grid { grid-template-columns: repeat(4, 1fr); }
}

@media (prefers-reduced-motion: reduce) {
  html { scroll-behavior: auto; }
  *,
  *::before,
  *::after {
    animation-duration: .01ms !important;
    animation-iteration-count: 1 !important;
    transition-duration: .01ms !important;
  }
}

@media print {
  .site-header,
  .site-footer,
  .toc,
  .button,
  .copy-button,
  .skip-link { display: none !important; }
  body { color: #000; background: #fff; font-size: 11pt; }
  .page-hero,
  .section,
  .content-grid { padding: 0; }
  a { color: #000; text-decoration: underline; }
  a[href^="http"]::after { content: " (" attr(href) ")"; font-size: .8em; }
  .article { max-width: none; }
}