/* ============================================================
   Informed Simplicity — site.css
   Sparse, warm-monochrome, system-stack, hairline-driven.
   Light-only palette.
   ============================================================ */

:root {
  color-scheme: light;
  --ink: #2C2C2C;
  --body: #5A5550;
  --muted: #8C8279;
  --muted-soft: #C4BAB0;
  --hairline: #C4BAB0;
  --hairline-soft: #DDD5C9;
  --canvas: #fefcf7;
  --surface-card: #F5F0EA;
  --surface-soft: #F5F0EA;
  --surface-strong: #E8DFD1;
  --nav-bg: rgba(254, 252, 247, 0.82);
  --on-primary: #fefcf7;
  --primary: #2C2C2C;
  --primary-active: #2C2C2C;

  --d-prime: #1d1d1f;
  --d-craft: #f5f5f7;
  --d-smoke: #6e6e73;
  --d-blood: #b42318;
  --d-green: #2f7d32;
  --d-amber: #b7791f;

  --font-sans: -apple-system, BlinkMacSystemFont, "Segoe UI", "Helvetica Neue", Helvetica, Arial, sans-serif;
  --font-mono: "SF Mono", ui-monospace, Menlo, Monaco, Consolas, monospace;

  --section: 96px;
  --section-sm: 64px;
  --block: 48px;
  --gap: 24px;
  --wrap: 760px;
  --wrap-wide: 1080px;

  --r-sm: 6px;
  --r-md: 8px;
  --r-lg: 12px;
  --r-xl: 14px;
  --r-pill: 980px;

  --t-display-xl: 4rem;
  --t-display-lg: 3rem;
  --t-display-md: 2.25rem;
  --t-display-sm: 1.75rem;
  --t-title-lg: 1.375rem;
  --t-title-md: 1.125rem;
  --t-body-lg: 1.125rem;
  --t-body-md: 1rem;
  --t-body-sm: 0.9375rem;
  --t-eyebrow: 0.75rem;
}

/* Base ---------------------------------------------------- */

* { box-sizing: border-box; }

html, body {
  margin: 0;
  padding: 0;
  background: var(--canvas);
  color: var(--ink);
  font-family: var(--font-sans);
  font-size: 17px;
  line-height: 1.55;
  -webkit-font-smoothing: antialiased;
  -moz-osx-font-smoothing: grayscale;
  text-rendering: optimizeLegibility;
}

a { color: inherit; text-decoration: none; }
button { font-family: inherit; }
img, svg { display: block; max-width: 100%; }
::selection { background: var(--ink); color: var(--canvas); }

/* Layout primitives -------------------------------------- */

.wrap {
  max-width: var(--wrap);
  margin: 0 auto;
  padding: 0 24px;
}

.wrap-wide {
  max-width: var(--wrap-wide);
  margin: 0 auto;
  padding: 0 24px;
}

/* Type --------------------------------------------------- */

.eyebrow {
  font-family: var(--font-mono);
  font-size: var(--t-eyebrow);
  font-weight: 600;
  letter-spacing: 0.12em;
  text-transform: uppercase;
  color: var(--muted);
  display: inline-block;
}

h1, h2, h3, h4 {
  margin: 0;
  font-weight: 700;
  color: var(--ink);
  letter-spacing: -0.02em;
  text-wrap: balance;
}

.display-lg { font-size: var(--t-display-lg); line-height: 1.05; letter-spacing: -0.03em; }
.display-md { font-size: var(--t-display-md); line-height: 1.12; letter-spacing: -0.025em; }
.display-sm { font-size: var(--t-display-sm); line-height: 1.18; letter-spacing: -0.02em; }

p { margin: 0; color: var(--body); text-wrap: pretty; }

.lead { font-size: var(--t-body-lg); line-height: 1.55; color: var(--body); }
.body-sm { font-size: var(--t-body-sm); color: var(--body); }
.muted { color: var(--muted); }

.signal {
  background: var(--ink);
  color: var(--canvas);
  padding: 0 6px;
  border-radius: 3px;
  font-weight: 700;
}

.memory {
  display: inline-block;
  border-left: 2px solid var(--ink);
  padding-left: 16px;
  font-weight: 500;
  color: var(--ink);
}

/* Nav ---------------------------------------------------- */

.nav {
  position: sticky;
  top: 0;
  z-index: 30;
  background: var(--nav-bg);
  backdrop-filter: saturate(180%) blur(14px);
  -webkit-backdrop-filter: saturate(180%) blur(14px);
  border-bottom: 1px solid var(--hairline);
}

.nav-inner {
  max-width: var(--wrap-wide);
  margin: 0 auto;
  padding: 0 24px;
  height: 60px;
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 24px;
}

.brand {
  font-size: 15px;
  font-weight: 600;
  letter-spacing: -0.01em;
  color: var(--ink);
  display: inline-flex;
  align-items: center;
  gap: 10px;
}

.brand-mark {
  width: 28px;
  height: 28px;
  border-radius: 8px;
  background: transparent url("/assets/is-mark.svg") center / contain no-repeat;
  display: inline-block;
  position: relative;
  flex-shrink: 0;
}
.brand-mark::after {
  content: none;
}

.nav-links {
  display: flex;
  align-items: center;
  gap: 28px;
}

.nav-link {
  font-size: 14px;
  font-weight: 500;
  color: var(--body);
  padding: 4px 0;
  position: relative;
  transition: color 0.15s ease;
}

.nav-link:hover { color: var(--ink); }

.nav-link[aria-current="page"] { color: var(--ink); }
.nav-link[aria-current="page"]::after {
  content: "";
  position: absolute;
  left: 0; right: 0; bottom: -20px;
  height: 1px;
  background: var(--ink);
}

.nav-cta {
  font-size: 14px;
  font-weight: 500;
  padding: 8px 16px;
  border-radius: var(--r-pill);
  background: var(--primary);
  color: var(--on-primary);
  border: 1px solid var(--primary);
  transition: transform 0.15s ease, background-color 0.15s ease;
}

.nav-cta:hover { background: var(--primary-active); transform: translateY(-1px); }

@media (max-width: 720px) {
  .nav-links { gap: 16px; }
  .nav-link { display: none; }
  .nav-link.always { display: inline-block; }
}

/* Buttons ------------------------------------------------ */

.cta {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  gap: 10px;
  height: 48px;
  padding: 0 28px;
  border-radius: var(--r-pill);
  font-size: 15px;
  font-weight: 500;
  background: var(--primary);
  color: var(--on-primary);
  border: 1px solid var(--primary);
  transition: transform 0.15s ease, background-color 0.15s ease;
}

.cta:hover { background: var(--primary-active); transform: translateY(-1px); }

.cta.secondary {
  background: transparent;
  color: var(--ink);
  border-color: var(--ink);
}
.cta.secondary:hover { background: var(--ink); color: var(--on-primary); transform: translateY(-1px); }

.cta-row {
  display: flex;
  flex-wrap: wrap;
  gap: 12px;
  margin-top: 32px;
}

/* Hero --------------------------------------------------- */

.hero { padding: 120px 0 var(--section); }

.hero h1 {
  font-size: var(--t-display-lg);
  line-height: 1.05;
  letter-spacing: -0.03em;
  margin: 18px 0 24px;
  max-width: 18ch;
}

.hero .lead { max-width: 56ch; }

/* Memo sections ------------------------------------------ */

.memo-section {
  padding: var(--section) 0;
  border-top: 1px solid var(--hairline);
}

.memo-section h2 { margin: 16px 0 20px; }
.memo-section .lead { max-width: 60ch; }
.memo-section .body-after { margin-top: 18px; max-width: 60ch; }

/* Grids and cards --------------------------------------- */

.grid {
  display: grid;
  gap: var(--gap);
  margin-top: var(--block);
}

.grid.cols-2 { grid-template-columns: repeat(2, 1fr); }
.grid.cols-3 { grid-template-columns: repeat(3, 1fr); }
.grid.cols-4 { grid-template-columns: repeat(4, 1fr); }

@media (max-width: 720px) {
  .grid.cols-2, .grid.cols-3, .grid.cols-4 { grid-template-columns: 1fr; }
}

.card {
  background: var(--surface-card);
  border: 1px solid var(--hairline);
  border-radius: var(--r-lg);
  padding: 24px;
  display: flex;
  flex-direction: column;
  gap: 8px;
  transition: transform 0.18s ease, border-color 0.18s ease;
}

.card:hover { transform: translateY(-2px); border-color: var(--muted-soft); }

.card .kicker {
  font-family: var(--font-mono);
  font-size: 11px;
  font-weight: 600;
  letter-spacing: 0.1em;
  text-transform: uppercase;
  color: var(--muted);
}

.card strong {
  font-size: var(--t-title-md);
  font-weight: 600;
  color: var(--ink);
  letter-spacing: -0.01em;
  line-height: 1.3;
}

.card p {
  font-size: var(--t-body-sm);
  color: var(--body);
}

.card.dark {
  background: var(--ink);
  border-color: var(--ink);
}
.card.dark .kicker { color: var(--muted-soft); }
.card.dark strong { color: var(--canvas); }
.card.dark p { color: var(--surface-strong); }

/* Step rows --------------------------------------------- */

.steps {
  margin-top: var(--block);
  border-top: 1px solid var(--hairline);
}

.step {
  display: grid;
  grid-template-columns: 64px 1fr;
  gap: 24px;
  padding: 28px 0;
  border-bottom: 1px solid var(--hairline);
  align-items: start;
}

.step-num {
  font-family: var(--font-mono);
  font-size: 14px;
  font-weight: 500;
  color: var(--muted-soft);
  padding-top: 4px;
}

.step-body strong {
  display: block;
  font-size: var(--t-title-md);
  font-weight: 600;
  color: var(--ink);
  letter-spacing: -0.01em;
  margin-bottom: 6px;
}

.step-body p { font-size: var(--t-body-sm); }

/* Provenance row ---------------------------------------- */

.provenance {
  display: flex;
  align-items: center;
  gap: 40px;
  flex-wrap: wrap;
  padding: 28px 0;
}

.provenance .label {
  font-family: var(--font-mono);
  font-size: 11px;
  letter-spacing: 0.1em;
  text-transform: uppercase;
  color: var(--muted);
  white-space: nowrap;
}

.provenance .mark {
  font-size: 15px;
  font-weight: 500;
  letter-spacing: -0.005em;
  color: var(--muted);
}

/* Diagnostic card (curve) ------------------------------- */

.diagnostic {
  margin-top: var(--block);
  border: 1px solid var(--hairline);
  border-radius: var(--r-lg);
  background: var(--surface-card);
  overflow: hidden;
}

.diagnostic-header {
  display: flex;
  align-items: baseline;
  justify-content: space-between;
  gap: 16px;
  padding: 20px 28px 18px;
}

.diagnostic-header .label {
  font-family: var(--font-mono);
  font-size: 11px;
  letter-spacing: 0.1em;
  text-transform: uppercase;
  color: var(--muted);
}

.diagnostic-header .title {
  font-size: var(--t-title-md);
  font-weight: 600;
  letter-spacing: -0.01em;
}

.curve-figure {
  position: relative;
  background: var(--canvas);
  border-top: 1px solid var(--hairline);
  border-bottom: 1px solid var(--hairline);
  padding: 24px 28px;
}

.curve-img { width: 100%; height: auto; display: block; }
.curve-img-dark { display: none; }

.curve-legend {
  display: grid;
  grid-template-columns: repeat(4, 1fr);
  gap: 0;
}

.curve-legend-item {
  display: grid;
  grid-template-columns: 32px 1fr;
  gap: 12px;
  padding: 22px 24px;
  align-items: start;
  border-right: 1px solid var(--hairline);
}
.curve-legend-item:last-child { border-right: 0; }

.curve-legend-num {
  font-family: var(--font-mono);
  font-size: 11px;
  font-weight: 600;
  letter-spacing: 0.1em;
  color: var(--muted);
  padding-top: 2px;
}

.curve-legend-item strong {
  display: block;
  font-size: 14px;
  font-weight: 600;
  color: var(--ink);
  letter-spacing: -0.005em;
  margin-bottom: 4px;
}

.curve-legend-item p {
  font-size: 13px;
  line-height: 1.5;
  color: var(--body);
}

@media (max-width: 820px) {
  .curve-legend { grid-template-columns: 1fr 1fr; }
  .curve-legend-item:nth-child(2) { border-right: 0; }
  .curve-legend-item:nth-child(1),
  .curve-legend-item:nth-child(2) { border-bottom: 1px solid var(--hairline); }
}
@media (max-width: 520px) {
  .curve-legend { grid-template-columns: 1fr; }
  .curve-legend-item { border-right: 0; border-bottom: 1px solid var(--hairline); }
  .curve-legend-item:last-child { border-bottom: 0; }
}

/* Offer ladder ------------------------------------------ */

.ladder {
  margin-top: var(--block);
  display: grid;
  grid-template-columns: 1fr;
  gap: 0;
  border-top: 1px solid var(--hairline);
}

.ladder-row {
  display: grid;
  grid-template-columns: 110px 1fr 150px 100px;
  gap: 28px;
  padding: 24px 0;
  padding-left: 20px;
  border-bottom: 1px solid var(--hairline);
  align-items: start;
}

.ladder-row .l-name {
  font-family: var(--font-mono);
  font-size: 12px;
  letter-spacing: 0.12em;
  text-transform: uppercase;
  color: var(--ink);
  font-weight: 600;
  padding-top: 2px;
}

.ladder-row .l-job {
  font-size: 16px;
  font-weight: 600;
  color: var(--ink);
  letter-spacing: -0.01em;
}

.ladder-row .l-job p {
  font-size: var(--t-body-sm);
  color: var(--body);
  font-weight: 400;
  margin-top: 6px;
}

.ladder-row .l-best {
  font-size: 13px;
  color: var(--muted);
  padding-top: 4px;
}

.ladder-row .l-price {
  font-family: var(--font-mono);
  font-size: 13px;
  color: var(--ink);
  text-align: right;
  padding-top: 4px;
}

.ladder-row.lead {
  background: linear-gradient(to right, var(--surface-soft), transparent);
}

@media (max-width: 820px) {
  .ladder-row {
    grid-template-columns: 1fr;
    gap: 8px;
    padding-left: 16px;
    padding-right: 16px;
  }
  .ladder-row .l-price { text-align: left; }
}

/* Altitude / scoreboard --------------------------------- */

.altitude-grid {
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: 16px;
  margin-top: var(--block);
}

@media (max-width: 720px) {
  .altitude-grid { grid-template-columns: 1fr; }
}

.scoreboard {
  margin-top: var(--block);
  border-top: 1px solid var(--hairline);
}

.scoreboard-row {
  display: grid;
  grid-template-columns: 280px 1fr;
  gap: 24px;
  padding: 24px 0;
  border-bottom: 1px solid var(--hairline);
  align-items: baseline;
}

.scoreboard-row strong {
  font-size: 18px;
  font-weight: 600;
  color: var(--ink);
  letter-spacing: -0.01em;
}

.scoreboard-row span { font-size: 16px; color: var(--body); }

@media (max-width: 720px) {
  .scoreboard-row { grid-template-columns: 1fr; gap: 4px; }
}

/* Final CTA --------------------------------------------- */

.final-cta {
  padding: var(--section) 0;
  border-top: 1px solid var(--hairline);
}

.final-cta h2 {
  font-size: var(--t-display-md);
  line-height: 1.12;
  letter-spacing: -0.025em;
  margin: 16px 0 18px;
  max-width: 24ch;
}

.final-cta .lead { max-width: 56ch; }

.final-cta .small-note {
  margin-top: 16px;
  font-size: 13px;
  color: var(--muted);
}

/* Footer ------------------------------------------------ */

.foot {
  border-top: 1px solid var(--hairline);
  padding: 56px 0 40px;
  margin-top: var(--section);
}

.foot-grid {
  display: grid;
  grid-template-columns: 1.4fr 1fr 1fr 1fr;
  gap: 24px;
  margin-bottom: 36px;
}

@media (max-width: 720px) {
  .foot-grid { grid-template-columns: 1fr 1fr; }
}

.foot-brand .desc {
  font-size: 14px;
  color: var(--muted);
  margin-top: 12px;
  max-width: 32ch;
}

.foot-group h4 {
  font-family: var(--font-mono);
  font-size: 11px;
  letter-spacing: 0.12em;
  text-transform: uppercase;
  font-weight: 600;
  color: var(--muted);
  margin: 0 0 14px;
}

.foot-group a {
  display: block;
  font-size: 14px;
  color: var(--body);
  padding: 4px 0;
  transition: color 0.15s ease;
}
.foot-group a:hover { color: var(--ink); }

.foot-bottom {
  display: flex;
  justify-content: space-between;
  align-items: center;
  flex-wrap: wrap;
  gap: 12px;
  padding-top: 28px;
  border-top: 1px solid var(--hairline);
  font-size: 13px;
  color: var(--muted);
}