/* backstop-design-system */
* { box-sizing: border-box; }
html { scroll-behavior: smooth; }
body { margin: 0; background: var(--color-paper); color: var(--color-ink); font-family: var(--font-sans); }
a { color: inherit; text-decoration: none; }
a:focus-visible { outline: var(--focus-ring); outline-offset: 4px; }

.shell { width: min(calc(100% - 48px), var(--content-width)); margin-inline: auto; }
.nav { height: 76px; display: flex; align-items: center; justify-content: space-between; border-bottom: 1px solid var(--color-line); }
.wordmark { display: inline-flex; align-items: baseline; font-size: 1rem; font-weight: 700; letter-spacing: -0.03em; }
.wordmark-mark { display: inline-grid; place-items: center; width: 31px; height: 25px; margin-right: 9px; background: var(--color-ink); color: var(--color-paper); border-radius: var(--radius-sm); font-family: var(--font-mono); font-size: 0.66rem; letter-spacing: -0.08em; }
.wordmark-domain { color: var(--color-muted); font-weight: 500; }
.nav-links { display: flex; gap: 30px; align-items: center; font-size: 0.84rem; font-weight: 530; }
.nav-links a { transition: color var(--motion-standard) ease; }
.nav-links a:hover { color: var(--color-muted); }
.arrow { font-family: var(--font-mono); font-size: 0.9em; }

.hero { padding-top: var(--space-9); }
.eyebrow, .section-kicker { font-family: var(--font-mono); text-transform: uppercase; letter-spacing: 0.1em; font-size: 0.69rem; font-weight: 700; }
.eyebrow { display: flex; align-items: center; gap: 9px; color: var(--color-muted); }
.status-dot { width: 7px; height: 7px; border-radius: 50%; background: var(--color-signal); box-shadow: var(--shadow-signal); }
h1 { max-width: 1000px; margin: 28px 0 0; font-size: clamp(3.5rem, 7.5vw, 6.85rem); line-height: 0.96; letter-spacing: -0.067em; font-weight: 620; }
h1 span { color: var(--color-muted); }
.hero-copy { max-width: 650px; margin: 36px 0 0; color: var(--color-muted); font-size: 1.14rem; line-height: 1.65; letter-spacing: -0.015em; }
.hero-actions { display: flex; gap: 12px; margin-top: 34px; }
.button { min-height: 44px; display: inline-flex; align-items: center; justify-content: center; gap: 10px; padding: 0 18px; border: 1px solid var(--color-ink); border-radius: var(--radius-sm); font-size: 0.82rem; font-weight: 650; transition: transform var(--motion-fast) ease, border-color var(--motion-fast) ease; }
.button:hover { transform: translateY(-1px); }
.button-primary { background: var(--color-ink); color: var(--color-paper); }
.button-secondary { border-color: var(--color-line); background: var(--color-surface); }
.button-secondary:hover { border-color: var(--color-ink); }

.terminal { margin-top: 76px; background: var(--color-terminal); color: var(--color-terminal-text); border-radius: var(--radius-md); overflow: hidden; box-shadow: var(--shadow-terminal); font-family: var(--font-mono); }
.terminal-bar { min-height: 52px; padding: 0 18px; border-bottom: 1px solid var(--color-line-dark); display: flex; align-items: center; justify-content: space-between; color: var(--color-terminal-bar); font-size: .74rem; }
.terminal-title { display: flex; gap: 10px; align-items: center; }
.terminal-icon { display: inline-grid; place-items: center; width: 23px; height: 23px; border: 1px solid var(--color-terminal-icon-border); border-radius: 5px; color: var(--color-signal); }
.copy-label { color: var(--color-terminal-faint); }
.terminal-body { padding: 28px 30px 30px; }
.command { font-size: .9rem; }
.prompt { color: var(--color-signal); padding-right: 12px; }
.checks { margin: 26px 0 24px; display: grid; gap: 12px; font-size: .76rem; }
.check { display: grid; grid-template-columns: auto 1fr 150px 54px; align-items: center; gap: 13px; color: var(--color-terminal-muted); }
.check-status { min-width: 210px; }
.check-icon { color: var(--color-signal); margin-right: 12px; }
.check-rule { height: 1px; background: repeating-linear-gradient(to right, var(--color-terminal-line) 0 3px, transparent 3px 7px); }
.check-detail { color: var(--color-terminal-faint); text-align: right; }
.check-result { color: var(--color-signal); text-align: right; }
.verdict { border-top: 1px solid var(--color-line-dark); padding-top: 22px; display: flex; align-items: center; gap: 16px; font-size: .75rem; }
.verdict > span:first-child { color: var(--color-signal); font-weight: 800; letter-spacing: .08em; }
.verdict-icon { display: inline-grid; place-items: center; width: 20px; height: 20px; margin-right: 7px; border-radius: 50%; background: var(--color-signal); color: var(--color-terminal); }
.verdict-copy { color: var(--color-terminal-muted); }
.exit-code { margin-left: auto; padding: 5px 8px; border: 1px solid var(--color-terminal-border); border-radius: 4px; color: var(--color-terminal-exit); }

.section-kicker { margin: 0 0 18px; color: var(--color-muted); }
.system-section { padding-block: var(--space-9); border-top: 1px solid var(--color-line); }
.system-section:first-of-type { margin-top: var(--space-10); }
.section-heading { display: grid; grid-template-columns: 64px 1fr; }
.section-number { padding-top: 8px; font-family: var(--font-mono); color: var(--color-faint); font-size: .68rem; }
.section-heading h2, .cta h2 { max-width: 850px; margin: 0; font-size: clamp(2.4rem, 5vw, 4.6rem); line-height: 1.03; letter-spacing: -0.052em; font-weight: 600; }
.section-body { display: grid; grid-template-columns: .72fr 1.28fr; gap: 90px; margin: 74px 0 0 64px; }
.prose p { margin: 0 0 20px; color: var(--color-muted); font-size: .96rem; line-height: 1.72; }
.prose .aside-ism { margin-top: 36px; padding-top: 24px; border-top: 1px solid var(--color-line); color: var(--color-ink); font-family: var(--font-mono); font-size: .78rem; font-weight: 700; }

.artifact-chain { border: 1px solid var(--color-line); border-radius: var(--radius-md); background: var(--color-surface); overflow: hidden; }
.main-chain { display: grid; grid-template-columns: repeat(4, 1fr); }
.artifact { position: relative; min-height: 124px; padding: 22px 18px; border-right: 1px solid var(--color-line); display: flex; flex-direction: column; justify-content: space-between; }
.artifact:last-child { border-right: 0; }
.artifact > span { font-family: var(--font-mono); color: var(--color-faint); font-size: .63rem; }
.artifact strong { font-size: .78rem; }
.artifact i { position: absolute; right: -10px; top: 50%; z-index: 1; width: 19px; height: 19px; display: grid; place-items: center; transform: translateY(-50%); background: var(--color-surface); border: 1px solid var(--color-line); border-radius: 50%; color: var(--color-muted); font-family: var(--font-mono); font-size: .65rem; font-style: normal; }
.issue-path { min-height: 58px; padding: 0 18px; border-top: 1px solid var(--color-line); display: grid; grid-template-columns: 1fr auto 34px auto; align-items: center; gap: 12px; font-size: .7rem; }
.issue-path > span { color: var(--color-faint); font-family: var(--font-mono); text-transform: uppercase; letter-spacing: .07em; font-size: .59rem; }
.issue-path i { color: var(--color-muted); font-family: var(--font-mono); font-style: normal; text-align: center; }
.trace { min-height: 54px; padding: 0 18px; border-top: 1px solid var(--color-line); display: flex; align-items: center; gap: 12px; color: var(--color-muted); font-family: var(--font-mono); font-size: .68rem; }
.trace span { width: 8px; height: 8px; border-radius: 50%; background: var(--color-signal); }

.standards-layout { align-items: start; }
.rule-panel, .baseline-panel { border: 1px solid var(--color-line); border-radius: var(--radius-md); background: var(--color-surface); overflow: hidden; }
.rule-panel-title { min-height: 48px; padding: 0 18px; display: flex; align-items: center; justify-content: space-between; border-bottom: 1px solid var(--color-line); background: var(--color-surface-muted); color: var(--color-muted); font-family: var(--font-mono); font-size: .65rem; }
.rule { min-height: 82px; padding: 16px 18px; display: grid; grid-template-columns: 190px 1fr; gap: 18px; align-items: start; border-bottom: 1px solid var(--color-line); }
.rule > span { padding-top: 3px; color: var(--color-faint); font-family: var(--font-mono); font-size: .62rem; }
.rule p { margin: 0; font-size: .78rem; line-height: 1.55; }
.enforcement-surfaces { display: grid; grid-template-columns: 1fr 1fr; }
.enforcement-surfaces div { padding: 18px; display: flex; flex-direction: column; gap: 8px; }
.enforcement-surfaces div + div { border-left: 1px solid var(--color-line); }
.enforcement-surfaces span { color: var(--color-faint); font-family: var(--font-mono); font-size: .62rem; text-transform: uppercase; letter-spacing: .08em; }
.enforcement-surfaces strong { font-size: .76rem; }

.baseline-row { min-height: 54px; padding: 0 16px; display: grid; grid-template-columns: 1fr 76px 76px 92px; align-items: center; border-bottom: 1px solid var(--color-line); font-family: var(--font-mono); font-size: .61rem; }
.baseline-head { min-height: 42px; background: var(--color-surface-muted); color: var(--color-faint); text-transform: uppercase; letter-spacing: .06em; }
.baseline-row strong { font-size: .61rem; font-weight: 700; }
.drift-panels { display: grid; gap: 14px; }
.drift-panel-title { min-height: 48px; padding: 0 16px; display: flex; align-items: center; justify-content: space-between; border-bottom: 1px solid var(--color-line); background: var(--color-surface-muted); }
.drift-panel-title span { color: var(--color-faint); font-family: var(--font-mono); font-size: .61rem; text-transform: uppercase; letter-spacing: .07em; }
.drift-panel-title strong { font-size: .7rem; }
.claim-row { min-height: 62px; padding: 0 16px; display: grid; grid-template-columns: 28px 1fr 72px; align-items: center; gap: 10px; border-bottom: 1px solid var(--color-line); }
.claim-row:last-child { border-bottom: 0; }
.claim-row div { display: flex; flex-direction: column; gap: 4px; }
.claim-row strong { font-size: .7rem; }
.claim-row small { color: var(--color-muted); font-family: var(--font-mono); font-size: .58rem; }
.claim-row b { font-family: var(--font-mono); font-size: .61rem; }
.claim-icon { width: 20px; height: 20px; display: grid; place-items: center; border-radius: 50%; font-size: .7rem; font-weight: 800; }
.claim-icon.ok { background: color-mix(in srgb, var(--color-signal) 16%, transparent); color: var(--color-signal-ink); }
.claim-icon.no { background: color-mix(in srgb, var(--color-danger) 13%, transparent); color: var(--color-danger-ink); }
.allowed { color: var(--color-muted); }
.improved { color: var(--color-signal-ink); }
.blocked { color: var(--color-danger-ink); }
.baseline-verdict { min-height: 76px; padding: 0 18px; display: flex; align-items: center; gap: 14px; border-radius: var(--radius-md); background: var(--color-danger-surface); color: var(--color-danger-text); }
.baseline-verdict > span { width: 25px; height: 25px; display: grid; place-items: center; border-radius: 50%; background: var(--color-danger); color: var(--color-danger-surface); font-weight: 800; }
.baseline-verdict div { display: flex; flex-direction: column; gap: 5px; }
.baseline-verdict strong { font-size: .75rem; }
.baseline-verdict small { color: var(--color-danger-muted); font-family: var(--font-mono); font-size: .62rem; }

.composition { padding-block: var(--space-10); border-top: 1px solid var(--color-line); display: grid; grid-template-columns: .78fr 1.22fr; gap: 100px; }
.composition-heading { position: sticky; top: 40px; align-self: start; }
.composition-heading h2 { margin: 0; font-size: clamp(2.4rem, 5vw, 4.6rem); line-height: 1.03; letter-spacing: -0.052em; font-weight: 600; }
.composition-heading > p:last-child { max-width: 430px; margin: 28px 0 0; color: var(--color-muted); font-size: .9rem; line-height: 1.7; }
.composition-list { border-top: 1px solid var(--color-line); }
.composition-row { min-height: 142px; padding: 28px 0; display: grid; grid-template-columns: 42px 190px 1fr; gap: 20px; border-bottom: 1px solid var(--color-line); }
.composition-row > span { padding-top: 3px; color: var(--color-faint); font-family: var(--font-mono); font-size: .63rem; }
.composition-row h3 { margin: 0 0 12px; font-size: .9rem; letter-spacing: -.02em; }
.composition-row code { color: var(--color-muted); font-family: var(--font-mono); font-size: .61rem; line-height: 1.5; }
.composition-row > p { margin: 0; color: var(--color-muted); font-size: .8rem; line-height: 1.65; }

.cta { margin-top: 70px; padding: 64px; background: var(--color-ink); color: var(--color-paper); display: flex; align-items: end; justify-content: space-between; border-radius: var(--radius-md); }
.cta .section-kicker { color: var(--color-ism); }
.button-inverse { border-color: var(--color-cta-border); background: var(--color-surface-muted); color: var(--color-ink); }
.footer { min-height: 160px; display: grid; grid-template-columns: 1fr auto 1fr; align-items: center; font-size: .75rem; color: var(--color-muted); }
.footer > a:last-child { justify-self: end; }

@media (max-width: 760px) {
  .shell { width: min(calc(100% - 32px), var(--content-width)); }
  .nav { height: 66px; }
  .nav-links a:not(:last-child) { display: none; }
  .hero { padding-top: 58px; }
  h1 { margin-top: 23px; font-size: clamp(3.15rem, 16vw, 5.4rem); line-height: .98; }
  .hero-copy { margin-top: 28px; font-size: 1rem; }
  .hero-actions { align-items: stretch; }
  .button { padding-inline: 14px; }
  .terminal { margin-top: 52px; }
  .terminal-body { padding: 24px 18px; overflow-x: auto; }
  .checks, .verdict { min-width: 510px; }
  .system-section { padding-block: 82px; }
  .system-section:first-of-type { margin-top: 100px; }
  .section-heading { grid-template-columns: 1fr; gap: 18px; }
  .section-number { padding: 0; }
  .section-body { grid-template-columns: 1fr; gap: 44px; margin: 46px 0 0; }
  .main-chain { grid-template-columns: 1fr; }
  .artifact { min-height: 74px; border-right: 0; border-bottom: 1px solid var(--color-line); }
  .artifact i { right: 20px; top: auto; bottom: -10px; transform: rotate(90deg); }
  .issue-path { grid-template-columns: 1fr auto 28px auto; }
  .rule { grid-template-columns: 1fr; gap: 8px; }
  .baseline-panel { overflow-x: auto; }
  .baseline-row { min-width: 620px; grid-template-columns: 1fr 76px 76px 92px; padding-inline: 12px; font-size: .58rem; }
  .composition { grid-template-columns: 1fr; gap: 52px; padding-block: 90px; }
  .composition-heading { position: static; }
  .composition-row { grid-template-columns: 34px 1fr; }
  .composition-row > p { grid-column: 2; }
  .cta { margin-top: 30px; padding: 40px 28px; align-items: start; flex-direction: column; gap: 36px; }
  .footer { min-height: 180px; grid-template-columns: 1fr auto; }
  .footer p { display: none; }
}

@media (prefers-reduced-motion: reduce) {
  html { scroll-behavior: auto; }
  *, *::before, *::after { transition-duration: var(--motion-reduced-duration) !important; }
}