/* Aspire Fuel Systems — landing page.
   Tokens mirror the product's design system (docs/Homebrew UI Source Renders/design_system/hb-tokens.css):
   warm charcoal dark by default, warm cream paper for .light sections, amber accent, IBM Plex. */
:root {
  --hb-font-sans: "IBM Plex Sans", "Inter", -apple-system, BlinkMacSystemFont, "Segoe UI", sans-serif;
  --hb-font-mono: "IBM Plex Mono", "JetBrains Mono", "SF Mono", ui-monospace, monospace;
  --hb-radius-sm: 3px;
  --hb-radius-md: 6px;
  --hb-radius-lg: 8px;
  --hb-radius-xl: 12px;

  --hb-bg-app: oklch(0.205 0.006 60);
  --hb-bg-surface: oklch(0.235 0.006 60);
  --hb-bg-raised: oklch(0.262 0.007 60);
  --hb-bg-hover: oklch(0.285 0.007 60);
  --hb-bg-divider: oklch(0.315 0.007 60);
  --hb-bg-border: oklch(0.35 0.008 60);
  --hb-fg-primary: oklch(0.96 0.004 80);
  --hb-fg-secondary: oklch(0.84 0.006 70);
  --hb-fg-tertiary: oklch(0.74 0.006 70);
  --hb-fg-muted: oklch(0.64 0.006 70);
  --hb-fg-faint: oklch(0.50 0.006 70);
  --hb-accent-base: oklch(0.78 0.14 75);
  --hb-accent-aa: oklch(0.78 0.14 75);
  --hb-accent-fg: oklch(0.205 0.006 60);
  --hb-accent-soft: oklch(0.30 0.06 75);
  --hb-accent-softer: oklch(0.24 0.03 75);

  --hb-state-critical-fg: oklch(0.75 0.16 27);
  --hb-state-critical-tint: oklch(0.27 0.08 27);
  --hb-state-critical-border: oklch(0.42 0.13 27);
  --hb-state-high-fg: oklch(0.80 0.16 42);
  --hb-state-high-tint: oklch(0.28 0.09 42);
  --hb-state-high-border: oklch(0.44 0.14 42);
  --hb-state-watch-fg: oklch(0.80 0.15 60);
  --hb-state-watch-tint: oklch(0.28 0.07 60);
  --hb-state-watch-border: oklch(0.43 0.11 60);
  --hb-state-healthy-fg: oklch(0.78 0.13 150);
  --hb-state-healthy-tint: oklch(0.26 0.06 150);
  --hb-state-healthy-border: oklch(0.40 0.09 150);

  /* Grade colours are mode-invariant in the product. */
  --grade-unl: #dc2626;
  --grade-pre: #2563eb;
  --grade-dsl: #16a34a;
}

/* Warm cream paper — the product's light theme. */
.light {
  --hb-bg-app: oklch(0.955 0.014 83);
  --hb-bg-surface: oklch(0.975 0.011 83);
  --hb-bg-raised: oklch(0.992 0.006 83);
  --hb-bg-divider: oklch(0.89 0.014 80);
  --hb-bg-border: oklch(0.84 0.016 78);
  --hb-fg-primary: oklch(0.22 0.008 60);
  --hb-fg-secondary: oklch(0.36 0.008 60);
  --hb-fg-tertiary: oklch(0.44 0.008 60);
  --hb-fg-muted: oklch(0.485 0.008 60);
  --hb-accent-base: oklch(0.60 0.15 55);
  --hb-accent-aa: oklch(0.54 0.15 55);
  background: var(--hb-bg-app);
  color: var(--hb-fg-primary);
}

* { box-sizing: border-box; }
html { scroll-behavior: smooth; }
body { margin: 0; font-family: var(--hb-font-sans); color: var(--hb-fg-primary); background: var(--hb-bg-app); -webkit-font-smoothing: antialiased; }
img { display: block; }
a { color: inherit; text-decoration: none; }
h1, h2, h3, p { margin: 0; }
.wrap { width: min(1180px, 100% - 48px); margin-inline: auto; }
.mono { font-family: var(--hb-font-mono); }
.dim { color: var(--hb-fg-muted); }
.accent { color: var(--hb-accent-base); }
.s-crit { color: var(--hb-state-critical-fg); }
.s-high { color: var(--hb-state-high-fg); }
.s-watch { color: var(--hb-state-watch-fg); }
.s-ok { color: var(--hb-state-healthy-fg); }

/* Nav */
.nav { position: sticky; top: 0; z-index: 10; background: oklch(0.205 0.006 60 / .94); backdrop-filter: blur(12px); border-bottom: 1px solid var(--hb-bg-divider); }
.nav-inner { display: flex; align-items: center; gap: 32px; height: 64px; }
.brand { display: flex; align-items: center; gap: 10px; font-weight: 600; font-size: 17px; letter-spacing: -.01em; color: var(--hb-fg-primary); }
.brand em { font-style: normal; font-weight: 400; color: var(--hb-fg-muted); }
.nav-links { display: flex; gap: 28px; margin-left: auto; font-size: 14px; color: var(--hb-fg-tertiary); }
.nav-links a:hover { color: var(--hb-fg-primary); }
.nav-actions { display: flex; align-items: center; gap: 20px; }
.nav-signin { font-size: 14px; font-weight: 500; color: var(--hb-fg-secondary); }
.nav-signin:hover { color: var(--hb-fg-primary); }

/* Buttons — amber is the product's primary action colour. */
.btn { display: inline-flex; align-items: center; gap: 8px; padding: 13px 22px; border-radius: var(--hb-radius-md); font-weight: 600; font-size: 15px; transition: transform .15s, filter .15s, border-color .15s; }
.btn:hover { transform: translateY(-1px); }
.btn:focus-visible { outline: 2px solid #3b82f6; outline-offset: 2px; }
.btn-sm { padding: 8px 14px; font-size: 13.5px; }
.btn-primary { background: var(--hb-accent-base); color: var(--hb-accent-fg); }
.btn-primary:hover { filter: brightness(1.07); }
.btn-ghost { border: 1px solid var(--hb-bg-border); color: var(--hb-fg-primary); background: var(--hb-bg-surface); }
.btn-ghost:hover { border-color: var(--hb-fg-faint); }

/* Hero */
.hero { background:
    radial-gradient(900px 460px at 50% -60px, oklch(0.78 0.14 75 / .13), transparent 70%),
    var(--hb-bg-app);
  padding: 92px 0 0; overflow: hidden; }
.hero-copy { text-align: center; }
.pill { display: inline-flex; align-items: center; gap: 9px; padding: 6px 14px; border: 1px solid var(--hb-accent-soft); border-radius: 999px; background: var(--hb-accent-softer); font-family: var(--hb-font-mono); font-size: 12.5px; font-weight: 500; letter-spacing: .14em; text-transform: uppercase; color: var(--hb-accent-base); }
.live { width: 7px; height: 7px; border-radius: 50%; background: var(--hb-state-healthy-fg); box-shadow: 0 0 0 4px oklch(0.78 0.13 150 / .18); }
.eyebrow { font-family: var(--hb-font-mono); font-size: 12.5px; font-weight: 500; letter-spacing: .16em; text-transform: uppercase; color: var(--hb-fg-muted); }
.hero .eyebrow { margin-top: 22px; }
section:not(.hero) .eyebrow { margin-bottom: 16px; color: var(--hb-accent-aa); }
h1 { margin: 22px auto 0; max-width: 1000px; font-size: clamp(42px, 7vw, 86px); font-weight: 600; line-height: 1; letter-spacing: -.045em; text-wrap: balance; }
.lede { margin: 26px auto 0; max-width: 640px; font-size: 19px; line-height: 1.55; color: var(--hb-fg-tertiary); text-wrap: balance; }
.cta-row { display: flex; justify-content: center; flex-wrap: wrap; gap: 12px; margin-top: 36px; }

/* Product frame — drawn in the product's own chrome. */
.app { margin: 72px auto 0; max-width: 1100px; border: 1px solid var(--hb-bg-border); border-bottom: 0; border-radius: var(--hb-radius-xl) var(--hb-radius-xl) 0 0; background: var(--hb-bg-app); box-shadow: 0 -24px 90px oklch(0.78 0.14 75 / .08), 0 30px 80px rgb(0 0 0 / .5); overflow: hidden; text-align: left; }
.app-top { display: flex; justify-content: space-between; align-items: center; height: 38px; padding: 0 16px; border-bottom: 1px solid var(--hb-bg-divider); font-size: 12.5px; font-weight: 600; }
.app-body { display: grid; grid-template-columns: 196px 1fr; min-height: 400px; }
.app-side { display: flex; flex-direction: column; gap: 2px; padding: 14px 10px; border-right: 1px solid var(--hb-bg-divider); font-size: 12.5px; color: var(--hb-fg-secondary); }
.app-brand { display: flex; align-items: center; gap: 8px; margin: 0 6px 12px; font-weight: 600; color: var(--hb-fg-primary); }
.side-group { margin: 10px 8px 4px; font-size: 12.5px; font-weight: 600; color: var(--hb-fg-primary); }
.app-side span { padding: 6px 10px 6px 20px; border-radius: var(--hb-radius-md); }
.app-side .on { background: var(--hb-accent-softer); color: var(--hb-accent-base); font-weight: 600; }
.app-main { padding: 18px 20px; min-width: 0; }
.app-head { display: flex; align-items: center; gap: 12px; flex-wrap: wrap; }
.glyph { display: grid; place-items: center; width: 30px; height: 30px; border: 1px solid var(--hb-accent-base); border-radius: var(--hb-radius-md); background: var(--hb-accent-softer); font-family: var(--hb-font-mono); font-weight: 600; color: var(--hb-accent-base); }
.app-head h3 { font-size: 20px; font-weight: 600; letter-spacing: -.02em; }
.live-tag { display: inline-flex; align-items: center; gap: 5px; font-family: var(--hb-font-mono); font-size: 10.5px; font-weight: 600; letter-spacing: .08em; text-transform: uppercase; color: var(--hb-state-healthy-fg); }
.live-tag i { width: 6px; height: 6px; border-radius: 50%; background: currentColor; }
.seg { display: inline-flex; gap: 2px; margin-left: auto; padding: 3px; border: 1px solid var(--hb-bg-border); border-radius: var(--hb-radius-md); font-size: 11.5px; color: var(--hb-fg-secondary); }
.seg > * { padding: 4px 10px; border-radius: var(--hb-radius-sm); }
.seg b { background: var(--hb-accent-base); color: var(--hb-accent-fg); font-weight: 600; }
.kpis { display: grid; grid-template-columns: repeat(5, 1fr); margin: 16px 0; border: 1px solid var(--hb-bg-border); border-radius: var(--hb-radius-lg); background: var(--hb-bg-surface); }
.kpis div { padding: 12px 14px; border-left: 1px solid var(--hb-bg-divider); min-width: 0; }
.kpis div:first-child { border-left: 0; }
.kpis b { font-family: var(--hb-font-mono); font-size: 22px; font-weight: 600; }
.kpis .k { margin-left: 6px; font-family: var(--hb-font-mono); font-size: 10.5px; font-weight: 600; letter-spacing: .08em; text-transform: uppercase; }
.kpis small { display: block; margin-top: 2px; font-size: 11.5px; color: var(--hb-fg-muted); white-space: nowrap; overflow: hidden; text-overflow: ellipsis; }
.grid { width: 100%; border-collapse: collapse; font-size: 12.5px; border: 1px solid var(--hb-bg-border); border-radius: var(--hb-radius-lg); background: var(--hb-bg-surface); }
.grid th { padding: 10px; text-align: left; font-family: var(--hb-font-mono); font-size: 10.5px; font-weight: 600; letter-spacing: .1em; text-transform: uppercase; color: var(--hb-fg-muted); border-bottom: 1px solid var(--hb-bg-divider); }
.grid td { padding: 11px 10px; border-bottom: 1px solid var(--hb-bg-divider); white-space: nowrap; font-weight: 500; }
.grid tr:last-child td { border-bottom: 0; }
.grid small { display: block; margin-top: 2px; font-family: var(--hb-font-sans); font-weight: 400; color: var(--hb-fg-muted); font-size: 11px; }
.tier { display: inline-block; padding: 2px 7px; border-radius: var(--hb-radius-sm); border: 1px solid; font-family: var(--hb-font-mono); font-size: 11px; font-weight: 600; letter-spacing: .08em; text-transform: uppercase; }
.t-crit { color: var(--hb-state-critical-fg); background: var(--hb-state-critical-tint); border-color: var(--hb-state-critical-border); }
.t-high { color: var(--hb-state-high-fg); background: var(--hb-state-high-tint); border-color: var(--hb-state-high-border); }
.t-watch { color: var(--hb-state-watch-fg); background: var(--hb-state-watch-tint); border-color: var(--hb-state-watch-border); }
.tank { display: inline-flex; align-items: center; gap: 7px; padding: 3px 8px 3px 3px; border: 1px solid; border-radius: var(--hb-radius-sm); font-family: var(--hb-font-mono); font-size: 11.5px; font-weight: 600; }
.g { display: inline-block; padding: 1px 5px; border-radius: var(--hb-radius-sm); font-family: var(--hb-font-mono); font-size: 11px; font-weight: 600; letter-spacing: .04em; color: #fff; vertical-align: 1px; }
.g-unl { background: var(--grade-unl); }
.g-pre { background: var(--grade-pre); }
.g-dsl { background: var(--grade-dsl); }
.bar { display: inline-block; vertical-align: middle; width: 70px; height: 4px; margin-left: 10px; border-radius: 2px; background: var(--hb-bg-divider); overflow: hidden; }
.bar i { display: block; height: 100%; background: var(--hb-state-critical-fg); }
.bar i.h { background: var(--hb-state-high-fg); }
.bar i.w { background: var(--hb-state-watch-fg); }
.figcap { padding: 10px 0 14px; text-align: center; font-size: 12px; color: var(--hb-fg-muted); }

/* Sections */
.band { padding: 104px 0; }
.section { padding: 112px 0; }
h2 { max-width: 780px; font-size: clamp(32px, 4.4vw, 50px); font-weight: 600; line-height: 1.06; letter-spacing: -.035em; text-wrap: balance; }
/* Product lockup — names the product above the modules; larger than an eyebrow so it reads as a heading. */
.product-mark { display: flex; align-items: center; gap: 12px; margin-bottom: 22px; font-size: 22px; font-weight: 500; letter-spacing: -.01em; color: var(--hb-fg-tertiary); }
.product-mark b { font-weight: 600; color: var(--hb-accent-aa); }
.sub { margin-top: 20px; max-width: 640px; font-size: 18px; line-height: 1.6; color: var(--hb-fg-tertiary); }
.cols3 { display: grid; grid-template-columns: repeat(3, 1fr); gap: 40px; margin-top: 56px; }
.cols3 article { padding-top: 22px; border-top: 2px solid var(--hb-accent-base); }
.cols3 h3, .modules h3 { font-size: 19px; font-weight: 600; letter-spacing: -.015em; }
.cols3 p, .modules p { margin-top: 10px; font-size: 15.5px; line-height: 1.6; color: var(--hb-fg-tertiary); }

/* Steps */
.steps { list-style: none; margin: 64px 0 0; padding: 0; display: grid; gap: 16px; }
.steps li { display: grid; grid-template-columns: 1fr 1fr; gap: 48px; align-items: center; padding: 34px; border: 1px solid var(--hb-bg-border); border-radius: var(--hb-radius-xl); background: var(--hb-bg-surface); }
.steps li > * { min-width: 0; }
.num { font-family: var(--hb-font-mono); font-size: 13px; font-weight: 600; letter-spacing: .14em; color: var(--hb-accent-base); }
.step-copy h3 { margin-top: 10px; font-size: 26px; font-weight: 600; letter-spacing: -.025em; }
.step-copy p { margin-top: 12px; font-size: 16.5px; line-height: 1.6; color: var(--hb-fg-tertiary); }
.card { padding: 20px; border: 1px solid var(--hb-bg-border); border-radius: var(--hb-radius-lg); background: var(--hb-bg-app); }
.label { font-family: var(--hb-font-mono); font-size: 10.5px; font-weight: 600; letter-spacing: .12em; text-transform: uppercase; color: var(--hb-fg-muted); }
.card .row { display: flex; justify-content: space-between; align-items: center; margin-top: 16px; padding-top: 14px; border-top: 1px solid var(--hb-bg-divider); font-size: 14px; color: var(--hb-fg-tertiary); }
.card .row b { font-weight: 600; color: var(--hb-fg-primary); }
.card .row b.s-crit { color: var(--hb-state-critical-fg); }
.chip { padding: 3px 8px; border: 1px solid var(--hb-state-healthy-border); border-radius: var(--hb-radius-sm); background: var(--hb-state-healthy-tint); font-family: var(--hb-font-mono); font-size: 10.5px; font-weight: 600; letter-spacing: .08em; text-transform: uppercase; }
.comps { display: flex; gap: 6px; margin-top: 14px; }
.comps span { display: flex; flex-direction: column; gap: 3px; padding: 10px; border-radius: var(--hb-radius-md); border: 1px solid; font-family: var(--hb-font-mono); font-size: 12px; color: var(--hb-fg-secondary); min-width: 0; }
.comps span b { font-size: 11px; font-weight: 600; letter-spacing: .06em; }
.c-unl { background: rgb(220 38 38 / .14); border-color: rgb(220 38 38 / .45); }
.c-unl b { color: #f87171; }
.c-pre { background: rgb(37 99 235 / .16); border-color: rgb(37 99 235 / .5); }
.c-pre b { color: #60a5fa; }
.c-dsl { background: rgb(22 163 74 / .14); border-color: rgb(22 163 74 / .45); }
.c-dsl b { color: #4ade80; }
.nlc, .recon { display: grid; gap: 6px; margin-top: 14px; }
.nlc div, .recon div { display: flex; justify-content: space-between; padding: 10px 12px; border-radius: var(--hb-radius-md); background: var(--hb-bg-surface); font-size: 14px; color: var(--hb-fg-tertiary); }
.nlc b, .recon b { font-family: var(--hb-font-mono); font-weight: 500; color: var(--hb-fg-primary); }
.nlc .best { background: var(--hb-state-healthy-tint); outline: 1px solid var(--hb-state-healthy-border); }
.nlc .best span::after { content: "Lowest"; margin-left: 10px; font-family: var(--hb-font-mono); font-size: 10.5px; font-weight: 600; letter-spacing: .1em; text-transform: uppercase; color: var(--hb-state-healthy-fg); }
.track { display: grid; grid-template-columns: repeat(4, 1fr); gap: 6px; margin-top: 16px; }
.track span { padding-top: 10px; border-top: 3px solid var(--hb-bg-divider); font-size: 12.5px; color: var(--hb-fg-muted); }
.track .done { border-color: var(--hb-state-healthy-fg); color: var(--hb-fg-primary); }
.track .now { border-color: var(--hb-accent-base); color: var(--hb-accent-base); }

/* Modules */
.modules { display: grid; grid-template-columns: repeat(3, 1fr); gap: 14px; margin-top: 56px; }
.modules article { padding: 24px; border-radius: var(--hb-radius-lg); background: var(--hb-bg-raised); border: 1px solid var(--hb-bg-border); }
.modules article:hover { border-color: var(--hb-accent-base); }

/* Control */
.split { display: grid; grid-template-columns: 1fr 1fr; gap: 64px; align-items: start; }
.checks { list-style: none; margin: 0; padding: 0; display: grid; gap: 22px; }
.checks li { position: relative; padding-left: 34px; font-size: 16.5px; line-height: 1.55; color: var(--hb-fg-tertiary); }
.checks li::before { content: ""; position: absolute; left: 0; top: 3px; width: 20px; height: 20px; border-radius: var(--hb-radius-md); background: var(--hb-accent-base) url("data:image/svg+xml,%3Csvg xmlns='http://www.w3.org/2000/svg' viewBox='0 0 20 20'%3E%3Cpath d='M5 10.5l3.2 3L15 7' fill='none' stroke='%231d1b19' stroke-width='2.4' stroke-linecap='round' stroke-linejoin='round'/%3E%3C/svg%3E") center/contain no-repeat; }
.checks b { color: var(--hb-fg-primary); font-weight: 600; }

/* CTA band */
.cta-band { padding: 120px 0; text-align: center; border-top: 1px solid var(--hb-bg-divider); background:
    radial-gradient(700px 340px at 50% 115%, oklch(0.78 0.14 75 / .2), transparent 70%),
    var(--hb-bg-app); }
.cta-band h2 { margin-inline: auto; font-size: clamp(38px, 5.4vw, 66px); }

/* Footer */
.footer { padding: 26px 0; border-top: 1px solid var(--hb-bg-divider); }
.footer-inner { display: flex; justify-content: space-between; align-items: center; gap: 16px; font-size: 13.5px; color: var(--hb-fg-muted); }
.footer .brand { font-size: 15px; }
.footer-links { display: flex; flex-wrap: wrap; gap: 8px 22px; }
.footer-links a:hover, .cta-note a:hover { color: var(--hb-fg-primary); }
.cta-note { margin-top: 22px; font-size: 14px; color: var(--hb-fg-muted); }
.cta-note a { color: var(--hb-fg-secondary); text-decoration: underline; text-underline-offset: 3px; }

/* Responsive */
@media (max-width: 960px) {
  .nav-links { display: none; }
  .nav-actions { margin-left: auto; }
  .app-body { grid-template-columns: minmax(0, 1fr); }
  .app-side, .seg { display: none; }
  .kpis { grid-template-columns: repeat(3, 1fr); }
  .kpis div:nth-child(4) { border-left: 0; }
  .kpis div:nth-child(n+4) { border-top: 1px solid var(--hb-bg-divider); }
  .grid th:nth-child(2), .grid td:nth-child(2) { display: none; }
  .cols3, .modules { grid-template-columns: 1fr 1fr; }
  .steps li, .split { grid-template-columns: minmax(0, 1fr); gap: 28px; }
}
@media (max-width: 600px) {
  .wrap { width: calc(100% - 32px); }
  .hero { padding-top: 60px; }
  .brand em { display: none; }
  .hero .eyebrow { font-size: 10.5px; letter-spacing: .1em; }
  .lede { font-size: 17px; }
  .app-main { padding: 14px 12px; }
  .kpis { grid-template-columns: 1fr 1fr; }
  .kpis div:nth-child(n) { border-left: 0; border-top: 1px solid var(--hb-bg-divider); }
  .kpis div:nth-child(-n+2) { border-top: 0; }
  .kpis div:nth-child(even) { border-left: 1px solid var(--hb-bg-divider); }
  .kpis div:nth-child(5) { display: none; }
  .grid th:nth-child(1), .grid td:nth-child(1), .grid th:nth-child(6), .grid td:nth-child(6) { display: none; }
  .cols3, .modules { grid-template-columns: 1fr; }
  .steps li { padding: 22px; }
  .band, .section, .cta-band { padding: 80px 0; }
  .footer-inner { flex-direction: column; text-align: center; }
  .footer-links { justify-content: center; }
  .nav-actions { gap: 14px; }
}
@media (prefers-reduced-motion: reduce) {
  html { scroll-behavior: auto; }
  .btn { transition: none; }
}

/* Tank level readout (step 1) — a single reading, not a time series. */
.level { position: relative; height: 34px; margin: 18px 0 26px; border: 1px solid var(--hb-bg-border); border-radius: var(--hb-radius-md); background: var(--hb-bg-surface); }
.level-fill { position: absolute; inset: 0 auto 0 0; border-radius: var(--hb-radius-md) 0 0 var(--hb-radius-md); background: var(--hb-state-critical-tint-strong, oklch(0.32 0.11 27)); border-right: 2px solid var(--hb-state-critical-fg); }
.level-mark { position: absolute; top: -4px; bottom: -4px; border-left: 1px dashed var(--hb-fg-muted); }
.level-mark small { position: absolute; top: calc(100% + 4px); left: -2px; white-space: nowrap; font-family: var(--hb-font-mono); font-size: 10.5px; color: var(--hb-fg-muted); }
.comps span small { font-family: var(--hb-font-sans); font-size: 11px; color: var(--hb-fg-muted); }