* { box-sizing: border-box; }
html { scroll-behavior: smooth; }
body { margin: 0; background: var(--colors-neutral); color: var(--colors-on-surface); font: var(--typography-body-font-size)/var(--typography-body-line-height) var(--typography-body-font-family); }
a { color: inherit; text-underline-offset: 5px; }
button { font: inherit; }
a, button, summary { -webkit-tap-highlight-color: transparent; }
:focus-visible { outline: 3px solid var(--colors-tertiary); outline-offset: 5px; }
h1, h2, h3, h4, p { margin-top: 0; }
h1, h2 { font-family: var(--typography-display-font-family); font-weight: 400; letter-spacing: -.045em; }
h1 { font-size: clamp(43px, 5.15vw, 78px); line-height: 1.12; margin-bottom: var(--spacing-lg); }
h2 { font-size: clamp(34px, 3.8vw, 55px); line-height: 1.12; margin-bottom: var(--spacing-lg); }
h3 { font-size: 25px; line-height: 1.3; font-weight: 400; }
h4 { font-size: 13px; line-height: 1.4; letter-spacing: .03em; margin: 0 0 var(--spacing-md); }
h1 em, .closing em { color: var(--colors-primary); }
p { margin-bottom: var(--spacing-md); }
.page { max-width: 1512px; padding: 0 clamp(20px, 5vw, 80px); margin: auto; }
.masthead { display: flex; align-items: center; gap: var(--spacing-lg); min-height: 88px; border-bottom: 1px solid var(--colors-muted); }
.brand { display: inline-flex; align-items: center; gap: 12px; text-decoration: none; font-size: 17px; font-weight: bold; letter-spacing: .08em; margin-right: auto; white-space: nowrap; }
.brand-mark { font: 30px/1 var(--typography-mono-font-family); color: var(--colors-primary); }
.masthead nav { display: flex; gap: var(--spacing-lg); }
.masthead nav a { font-size: 13px; text-decoration: none; padding: 14px 0; }
.masthead nav a:hover { text-decoration: underline; }
.edition { border-left: 1px solid var(--colors-muted); padding-left: var(--spacing-lg); font: 10px/1.5 var(--typography-mono-font-family); letter-spacing: .1em; }
.eyebrow, .package, .tab-number, .flow-label, .evidence-label { font: 11px/1.6 var(--typography-mono-font-family); letter-spacing: .06em; }
.eyebrow { color: var(--colors-secondary); margin-bottom: var(--spacing-md); }
.hero { display: grid; grid-template-columns: minmax(0, 1fr) 255px; gap: var(--spacing-xl); padding: 76px 0 62px; align-items: center; }
.lede { font-size: 18px; max-width: 790px; line-height: 1.7; }
.hero-aside { border-left: 1px solid var(--colors-muted); padding-left: var(--spacing-lg); }
.five { font: 116px/.9 var(--typography-display-font-family); letter-spacing: -.08em; color: var(--colors-primary); }
.five span { display: block; font: 11px/1.6 var(--typography-mono-font-family); letter-spacing: .03em; margin: var(--spacing-md) 0 var(--spacing-lg); }
.role-list { padding: 0; margin: 0; list-style: none; }
.role-list li { display: flex; gap: var(--spacing-md); padding: 10px 0; border-top: 1px solid var(--colors-muted); font-size: 13px; }
.role-list span { font: 11px/1.8 var(--typography-mono-font-family); color: var(--colors-tertiary); }
.primary { display: inline-flex; gap: var(--spacing-xl); align-items: center; justify-content: space-between; min-height: 52px; padding: var(--spacing-md) var(--spacing-lg); background: var(--colors-primary); color: var(--colors-surface); text-decoration: none; border-radius: var(--rounded-sm); margin: var(--spacing-lg) 0 var(--spacing-md); }
.primary:hover { background: var(--colors-on-surface); }
.hero-note { font-size: 12px; color: var(--colors-secondary); }
.layer-strip { display: grid; grid-template-columns: 1fr auto 1fr auto 1fr; align-items: start; gap: var(--spacing-lg); padding: var(--spacing-lg) 0; border-top: 1px solid var(--colors-on-surface); border-bottom: 1px solid var(--colors-muted); }
.layer-strip .eyebrow { display: block; margin-bottom: var(--spacing-sm); }
.layer-strip strong { font-size: 19px; font-weight: 400; display: block; }
.layer-strip p { font-size: 13px; color: var(--colors-secondary); margin: var(--spacing-sm) 0 0; }
.connector { align-self: center; font-size: 26px; color: var(--colors-secondary); }
.section { padding-top: 80px; scroll-margin-top: var(--spacing-lg); }
.section-heading { display: flex; justify-content: space-between; gap: var(--spacing-xl); align-items: end; margin-bottom: var(--spacing-lg); }
.section-intro { max-width: 390px; font-size: 14px; color: var(--colors-secondary); }
.skill-layout { display: grid; grid-template-columns: 310px minmax(0, 1fr); gap: var(--spacing-lg); align-items: start; }
.skill-nav { display: flex; flex-direction: column; gap: var(--spacing-sm); }
.skill-nav button { display: flex; flex-direction: column; gap: 6px; width: 100%; text-align: left; padding: var(--spacing-lg); border: 1px solid var(--colors-muted); border-left: 3px solid var(--colors-muted); border-radius: var(--rounded-sm); background: transparent; color: var(--colors-on-surface); cursor: pointer; min-height: 132px; }
.skill-nav button strong { font-size: 18px; line-height: 1.45; font-weight: 400; }
.skill-nav button > span:last-child { font-size: 12px; color: var(--colors-secondary); }
.skill-nav button:hover { background: var(--colors-surface); }
.tab-number { color: var(--colors-tertiary); }
.skill-nav button[aria-selected="true"] { background: var(--colors-primary); color: var(--colors-surface); border-color: var(--colors-primary); }
.skill-nav button[aria-selected="true"] .tab-number, .skill-nav button[aria-selected="true"] > span:last-child { color: var(--colors-muted); }
.skill-panel { background: var(--colors-surface); border: 1px solid var(--colors-muted); border-radius: var(--rounded-md); padding: clamp(24px, 3vw, 44px); min-width: 0; margin-bottom: var(--spacing-lg); }
.skill-panel[hidden] { display: none; }
.package { color: var(--colors-tertiary); overflow-wrap: anywhere; margin-bottom: var(--spacing-md); }
.skill-panel h3 { font: 38px/1.15 var(--typography-display-font-family); letter-spacing: -.03em; margin-bottom: var(--spacing-lg); }
.panel-lede { font-size: 17px; line-height: 1.7; }
.panel-columns { display: grid; grid-template-columns: 1fr 1fr; gap: var(--spacing-lg); margin: var(--spacing-lg) 0; padding-top: var(--spacing-lg); border-top: 1px solid var(--colors-muted); font-size: 14px; }
.panel-columns ul { padding-left: 18px; margin: 0; }
.panel-columns li { margin-bottom: 10px; padding-left: 2px; }
.panel-columns h4:not(:first-child) { margin-top: var(--spacing-lg); }
.example { padding: var(--spacing-lg); background: var(--colors-neutral); border-radius: var(--rounded-sm); margin-bottom: var(--spacing-lg); }
.example .eyebrow { display: block; margin-bottom: var(--spacing-sm); }
blockquote { margin: 0; font: 21px/1.55 var(--typography-display-font-family); }
.example .small { margin: var(--spacing-md) 0 0; }
.small { font-size: 12px; color: var(--colors-secondary); }
.scope-note { border-left: 2px solid var(--colors-warning); padding-left: var(--spacing-md); font-size: 13px; line-height: 1.7; }
.mechanics { border-top: 1px solid var(--colors-muted); padding-top: var(--spacing-md); margin: var(--spacing-lg) 0 0; color: var(--colors-secondary); font-size: 12px; }
.mechanics span { display: block; text-transform: uppercase; font: 10px/1.5 var(--typography-mono-font-family); margin-bottom: 6px; }
.handoff-grid { display: grid; grid-template-columns: 1fr 1fr; border-top: 1px solid var(--colors-muted); }
.handoff-grid article { padding: 32px 32px 32px 0; border-bottom: 1px solid var(--colors-muted); }
.handoff-grid article:nth-child(even) { padding-left: 32px; border-left: 1px solid var(--colors-muted); }
.flow-label { display: block; color: var(--colors-tertiary); margin-bottom: var(--spacing-md); }
.handoff-grid h3 { font-size: 23px; }
.handoff-grid h3 span { color: var(--colors-secondary); }
.handoff-grid p { font-size: 14px; max-width: 540px; margin-bottom: 0; }
.field-example { display: grid; grid-template-columns: 1.2fr 1fr; gap: var(--spacing-2xl); margin-top: 80px; padding: var(--spacing-xl); border-radius: var(--rounded-md); background: var(--colors-primary); color: var(--colors-surface); }
.field-example .eyebrow, .field-example .small, .field-example .flow-label { color: var(--colors-muted); }
.field-example h2 { font-size: 48px; }
.field-example p:last-child { margin-bottom: 0; }
.field-example aside { border-left: 1px solid var(--colors-secondary); padding-left: var(--spacing-xl); align-self: center; }
.field-example aside ul { padding-left: 18px; margin: var(--spacing-lg) 0; }
.field-example aside li { margin-bottom: var(--spacing-md); }
.evidence-grid { display: grid; grid-template-columns: repeat(3, 1fr); gap: var(--spacing-lg); }
.evidence-grid article { padding: var(--spacing-lg) 0; border-top: 3px solid var(--colors-primary); }
.evidence-grid article:last-child { border-color: var(--colors-tertiary); }
.evidence-label { display: block; color: var(--colors-secondary); margin-bottom: var(--spacing-lg); }
.evidence-grid h3 { font-size: 23px; }
.evidence-grid p { font-size: 14px; margin: 0; }
.review-details { border-top: 1px solid var(--colors-muted); border-bottom: 1px solid var(--colors-muted); font-size: 14px; }
summary { cursor: pointer; min-height: 52px; padding: var(--spacing-md) 0; text-decoration: underline; text-underline-offset: 5px; }
.review-details ul { padding-left: 20px; max-width: 1040px; }
.review-details li { margin-bottom: var(--spacing-md); }
.closing { text-align: center; padding: 100px 0; }
.closing h2 { font-size: clamp(40px, 4.7vw, 65px); }
.closing p:not(.eyebrow) { font-size: 17px; }
.text-link { display: inline-block; min-height: 48px; padding: var(--spacing-md) 0; }
footer { border-top: 1px solid var(--colors-muted); display: flex; justify-content: space-between; gap: var(--spacing-xl); padding: var(--spacing-lg) 0; font-size: 11px; color: var(--colors-secondary); }
footer strong { font: 11px/1.6 var(--typography-mono-font-family); }
footer p { margin: 6px 0 0; }
.skip { position: absolute; top: -100px; padding: var(--spacing-md); background: var(--colors-surface); z-index: 2; }
.skip:focus { top: 12px; }
@media (max-width: 1100px) {
  .edition { display: none; }
  .hero { grid-template-columns: minmax(0, 1fr) 220px; gap: var(--spacing-lg); }
  .skill-layout { grid-template-columns: 260px minmax(0, 1fr); gap: var(--spacing-md); }
  .skill-nav button { padding: var(--spacing-md); }
  .panel-columns { grid-template-columns: 1fr; }
  .field-example { gap: var(--spacing-lg); }
  .field-example aside { padding-left: var(--spacing-lg); }
}
@media (max-width: 760px) {
  .masthead { flex-wrap: wrap; gap: 0; padding: var(--spacing-md) 0; }
  .brand { width: 100%; margin-bottom: var(--spacing-sm); }
  .masthead nav { width: 100%; justify-content: space-between; gap: 12px; }
  .masthead nav a { font-size: 11px; }
  .hero { grid-template-columns: 1fr; padding: var(--spacing-xl) 0; }
  .hero-aside { border-left: 0; border-top: 1px solid var(--colors-muted); padding: var(--spacing-lg) 0 0; }
  .five { font-size: 72px; display: flex; gap: var(--spacing-lg); align-items: end; }
  .five span { margin-bottom: 4px; }
  .role-list { display: grid; grid-template-columns: 1fr 1fr; gap: 0 var(--spacing-md); margin-top: var(--spacing-lg); }
  .role-list li { font-size: 12px; }
  .lede { font-size: 16px; }
  .layer-strip { grid-template-columns: 1fr; gap: var(--spacing-lg); }
  .connector { display: none; }
  .layer-strip > div + div { border-top: 1px solid var(--colors-muted); }
  .section { padding-top: 54px; }
  .section-heading { display: block; }
  .section-intro { max-width: none; }
  .skill-layout { grid-template-columns: 1fr; }
  .skill-nav { display: grid; grid-template-columns: 1fr 1fr; }
  .skill-nav button { min-height: 150px; }
  .skill-nav button strong { font-size: 16px; }
  .skill-nav button:last-child { grid-column: 1 / -1; min-height: 120px; }
  .tab-number { font-size: 10px; }
  .skill-panel { padding: var(--spacing-lg); }
  .skill-panel h3 { font-size: 32px; }
  .panel-lede { font-size: 16px; }
  .example { padding: var(--spacing-md); }
  .handoff-grid { grid-template-columns: 1fr; }
  .handoff-grid article, .handoff-grid article:nth-child(even) { padding: var(--spacing-lg) 0; border-left: 0; }
  .field-example { margin-top: 54px; padding: var(--spacing-lg); grid-template-columns: 1fr; }
  .field-example h2 { font-size: 37px; }
  .field-example aside { border-left: 0; border-top: 1px solid var(--colors-secondary); padding: var(--spacing-lg) 0 0; }
  .evidence-grid { grid-template-columns: 1fr; gap: 0; }
  .closing { padding: 66px 0; }
  footer { flex-direction: column; gap: var(--spacing-md); }
}
@media (prefers-reduced-motion: reduce) { html { scroll-behavior: auto; } }
@media print {
  body { background: var(--colors-surface); }
  .page { padding: 0; }
  .masthead nav, .skill-nav, .primary, .skip { display: none; }
  .skill-layout { display: block; }
  .skill-panel[hidden] { display: block; }
  .skill-panel { break-inside: avoid; }
  h1 { font-size: 44px; }
  .hero { padding: 30px 0; }
  .field-example { background: var(--colors-surface); color: var(--colors-on-surface); border: 1px solid; }
  .field-example .eyebrow, .field-example .small, .field-example .flow-label { color: var(--colors-secondary); }
  details > * { display: block !important; }
}