/* =========================================================
   EstimatePro — shared design system
   Dark surface, amber accent. Same aesthetic as v0.
   ========================================================= */

:root {
  /* surface */
  --bg:           #0f1115;
  --bg-2:         #14171d;
  --surface:      #1a1c22;
  --surface-2:    #20232b;
  --border:       #27272a;
  --border-2:     #34353b;

  /* text */
  --text:         #e8e8ea;
  --text-2:       #9ca3af;
  --text-3:       #71717a;

  /* accent */
  --amber:        #f59e0b;
  --amber-2:      #fbbf24;
  --amber-soft:   rgba(245, 158, 11, 0.10);
  --amber-border: rgba(245, 158, 11, 0.35);

  /* state */
  --success:      #10b981;
  --success-soft: rgba(16, 185, 129, 0.10);

  /* layout */
  --radius:       14px;
  --radius-sm:    10px;
  --radius-pill:  999px;
  --shadow:       0 1px 0 rgba(255,255,255,0.02), 0 12px 32px rgba(0,0,0,0.25);
  --maxw:         1120px;
}

/* ----- reset ----- */
* { box-sizing: border-box; margin: 0; padding: 0; }
html { -webkit-text-size-adjust: 100%; scroll-behavior: smooth; }
body {
  min-height: 100vh;
  background: var(--bg);
  color: var(--text);
  font-family: -apple-system, BlinkMacSystemFont, "Segoe UI", Roboto, "Helvetica Neue", Arial, sans-serif;
  font-size: 16px;
  line-height: 1.55;
  -webkit-font-smoothing: antialiased;
  text-rendering: optimizeLegibility;
}
a { color: var(--amber-2); text-decoration: none; }
a:hover { text-decoration: underline; }
img, svg { display: block; max-width: 100%; }
button { font: inherit; cursor: pointer; }
input, select, textarea { font: inherit; color: inherit; }

/* ----- layout ----- */
.container {
  max-width: var(--maxw);
  margin: 0 auto;
  padding: 0 24px;
}
.section { padding: 64px 0; }
.section-sm { padding: 40px 0; }
.grid-2 { display: grid; grid-template-columns: 1fr; gap: 20px; }
@media (min-width: 720px) { .grid-2 { grid-template-columns: 1fr 1fr; } }

/* ----- type ----- */
.h1 {
  font-size: clamp(2rem, 4.5vw, 3rem);
  font-weight: 800;
  letter-spacing: -0.025em;
  line-height: 1.08;
}
.h2 {
  font-size: clamp(1.5rem, 2.5vw, 1.875rem);
  font-weight: 700;
  letter-spacing: -0.02em;
  line-height: 1.2;
}
.h3 {
  font-size: 1.125rem;
  font-weight: 600;
  letter-spacing: -0.01em;
}
.eyebrow {
  font-size: 0.75rem;
  font-weight: 700;
  letter-spacing: 0.12em;
  text-transform: uppercase;
  color: var(--amber);
}
.lead {
  font-size: 1.0625rem;
  color: var(--text-2);
  line-height: 1.6;
  max-width: 56ch;
}
.text-2 { color: var(--text-2); }
.text-3 { color: var(--text-3); }
.mono  { font-variant-numeric: tabular-nums; }

/* gradient headline (for hero / totals) */
.gradient {
  background: linear-gradient(90deg, var(--amber), var(--amber-2));
  -webkit-background-clip: text;
  background-clip: text;
  color: transparent;
}

/* ----- buttons ----- */
.btn {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  gap: 8px;
  padding: 12px 20px;
  border-radius: var(--radius-sm);
  font-weight: 600;
  font-size: 0.9375rem;
  border: 1px solid transparent;
  transition: transform .12s ease, background .12s ease, border-color .12s ease;
  text-decoration: none;
}
.btn:hover { text-decoration: none; transform: translateY(-1px); }
.btn-primary {
  background: linear-gradient(180deg, var(--amber-2), var(--amber));
  color: #1a1206;
  border-color: var(--amber);
}
.btn-primary:hover { background: linear-gradient(180deg, #fcd34d, var(--amber-2)); }
.btn-ghost {
  background: transparent;
  color: var(--text);
  border-color: var(--border-2);
}
.btn-ghost:hover { border-color: var(--amber-border); }
.btn-sm { padding: 8px 14px; font-size: 0.875rem; }

/* ----- header / nav ----- */
.nav {
  position: sticky; top: 0; z-index: 10;
  background: rgba(15, 17, 21, 0.85);
  backdrop-filter: saturate(140%) blur(8px);
  -webkit-backdrop-filter: saturate(140%) blur(8px);
  border-bottom: 1px solid var(--border);
}
.nav-inner {
  display: flex; align-items: center; justify-content: space-between;
  padding: 14px 24px; max-width: var(--maxw); margin: 0 auto;
}
.brand {
  display: flex; align-items: center; gap: 10px;
  font-weight: 800; letter-spacing: -0.02em; color: var(--text);
}
.brand-mark {
  width: 26px; height: 26px; border-radius: 7px;
  background: linear-gradient(135deg, var(--amber), var(--amber-2));
  box-shadow: 0 0 0 1px var(--amber-border), 0 6px 16px rgba(245,158,11,0.25);
}
.nav-links { display: flex; gap: 18px; align-items: center; }
.nav-links a { color: var(--text-2); font-size: 0.875rem; font-weight: 500; }
.nav-links a:hover { color: var(--text); text-decoration: none; }
@media (max-width: 600px) { .nav-links a.hide-sm { display: none; } }

/* ----- hero ----- */
.hero {
  padding: 72px 0 40px;
  text-align: center;
}
.hero h1 { margin: 14px auto 18px; max-width: 18ch; }
.hero .lead { margin: 0 auto 28px; }
.hero-cta { display: flex; gap: 12px; justify-content: center; flex-wrap: wrap; }

/* ----- trust strip ----- */
.trust {
  border-top: 1px solid var(--border);
  border-bottom: 1px solid var(--border);
  background: var(--bg-2);
}
.trust-inner {
  display: flex; flex-wrap: wrap; gap: 12px 28px; justify-content: center;
  padding: 18px 24px; max-width: var(--maxw); margin: 0 auto;
  font-size: 0.8125rem; color: var(--text-2);
}
.trust-inner strong { color: var(--text); font-weight: 600; }
.trust-dot { color: var(--text-3); }

/* ----- cards (active calculators) ----- */
.cards {
  display: grid; gap: 20px;
  grid-template-columns: 1fr;
}
@media (min-width: 720px) { .cards { grid-template-columns: 1fr 1fr; } }
.card {
  background: var(--surface);
  border: 1px solid var(--border);
  border-radius: var(--radius);
  padding: 24px;
  display: flex; flex-direction: column; gap: 14px;
  transition: border-color .15s ease, transform .15s ease;
}
.card:hover { border-color: var(--amber-border); transform: translateY(-2px); }
.card h3 { font-size: 1.25rem; }
.card .sample {
  font-size: 0.875rem; color: var(--text-2);
  background: var(--bg-2); border: 1px solid var(--border);
  border-radius: var(--radius-sm); padding: 10px 12px;
}
.card .sample strong { color: var(--text); font-weight: 700; }
.card .meta { display: flex; gap: 10px; align-items: center; font-size: 0.75rem; color: var(--text-3); }
.card .meta .badge-live {
  display: inline-block; padding: 2px 8px; border-radius: var(--radius-pill);
  background: var(--success-soft); color: var(--success); font-weight: 600;
  border: 1px solid rgba(16,185,129,0.25);
}
.card .actions { margin-top: auto; display: flex; gap: 10px; }

/* ----- roadmap pills ----- */
.roadmap {
  display: flex; flex-wrap: wrap; gap: 10px;
  margin-top: 20px;
}
.pill {
  display: inline-flex; align-items: center; gap: 8px;
  padding: 8px 14px; border-radius: var(--radius-pill);
  background: var(--bg-2);
  border: 1px solid var(--border);
  color: var(--text-2);
  font-size: 0.875rem; font-weight: 500;
}
.pill .pill-eta {
  color: var(--text-3); font-size: 0.75rem; font-weight: 600;
  padding-left: 8px; border-left: 1px solid var(--border-2);
}

/* ----- how it works ----- */
.steps {
  display: grid; gap: 20px;
  grid-template-columns: 1fr;
}
@media (min-width: 720px) { .steps { grid-template-columns: repeat(3, 1fr); } }
.step {
  background: var(--surface);
  border: 1px solid var(--border);
  border-radius: var(--radius);
  padding: 22px;
}
.step .num {
  display: inline-flex; align-items: center; justify-content: center;
  width: 32px; height: 32px; border-radius: 9px;
  background: var(--amber-soft); color: var(--amber-2);
  font-weight: 700; font-size: 0.875rem;
  border: 1px solid var(--amber-border);
  margin-bottom: 12px;
}
.step h3 { margin-bottom: 6px; }
.step p  { color: var(--text-2); font-size: 0.9375rem; }

/* ----- "why ranges" callout ----- */
.callout {
  background: var(--bg-2);
  border: 1px solid var(--border);
  border-radius: var(--radius);
  padding: 28px;
  display: grid; gap: 18px;
  grid-template-columns: 1fr;
}
@media (min-width: 720px) { .callout { grid-template-columns: 200px 1fr; align-items: start; } }
.callout h3 { color: var(--amber-2); }
.callout p  { color: var(--text-2); }

/* ----- footer ----- */
.footer {
  border-top: 1px solid var(--border);
  padding: 40px 0 60px;
  color: var(--text-3);
  font-size: 0.875rem;
}
.footer-inner {
  max-width: var(--maxw); margin: 0 auto; padding: 0 24px;
  display: flex; flex-wrap: wrap; gap: 18px; justify-content: space-between; align-items: center;
}
.footer a { color: var(--text-2); }
.footer .assumptions {
  max-width: var(--maxw); margin: 16px auto 0; padding: 0 24px;
  color: var(--text-3); font-size: 0.8125rem; line-height: 1.6;
}

/* ----- breadcrumb nav ----- */
.breadcrumb {
  display: flex;
  align-items: center;
  gap: 8px;
  padding: 20px 24px 0;
  max-width: var(--maxw);
  margin: 0 auto;
  font-size: 0.8125rem;
  color: var(--text-3);
}
.breadcrumb a { color: var(--text-2); }
.breadcrumb a:hover { color: var(--amber-2); text-decoration: none; }
.breadcrumb .bc-sep { color: var(--border-2); font-size: 0.75rem; }

/* ----- calc page H2 ----- */
.calc-h2 {
  font-size: 1.125rem !important;
  margin-bottom: -10px !important;
}

/* ----- calculator page ----- */
.calc-hero { padding: 28px 0 16px; }
.calc-hero h1 { font-size: clamp(1.75rem, 3.5vw, 2.5rem); font-weight: 800; letter-spacing: -0.02em; }
.calc-hero .lead { margin-top: 10px; }

.calc-grid {
  display: grid; gap: 24px;
  grid-template-columns: 1fr;
  align-items: start;
}
@media (min-width: 920px) { .calc-grid { grid-template-columns: 1.15fr 1fr; } }
.calc-content { min-width: 0; }

/* spectrum bar (replaces 3-column bands) */
.spectrum-bar {
  display: flex; flex-direction: column; gap: 8px;
}
.spectrum-track {
  position: relative;
  height: 10px;
  background: var(--surface-2);
  border-radius: 5px;
  border: 1px solid var(--border);
  overflow: visible;
}
.spectrum-fill {
  position: absolute;
  top: 0; bottom: 0; left: 0;
  border-radius: 5px;
  background: linear-gradient(90deg,
    rgba(245,158,11,0.18) 0%,
    var(--amber-2) 50%,
    rgba(245,158,11,0.18) 100%
  );
  transition: left 0.35s cubic-bezier(0.4,0,0.2,1), width 0.35s cubic-bezier(0.4,0,0.2,1);
}
.spectrum-marker {
  position: absolute;
  top: 50%; transform: translate(-50%, -50%);
  width: 20px; height: 20px;
  border-radius: 50%;
  background: var(--amber-2);
  border: 3px solid var(--bg);
  box-shadow: 0 0 0 1px var(--amber-border), 0 4px 12px rgba(245,158,11,0.4);
  transition: left 0.35s cubic-bezier(0.4,0,0.2,1);
  z-index: 2;
}
.spectrum-labels {
  display: flex; justify-content: space-between;
  font-size: 0.75rem; font-weight: 700; letter-spacing: 0.08em; text-transform: uppercase;
}
.spectrum-labels .lo { color: var(--text-3); }
.spectrum-labels .mi { color: var(--amber); }
.spectrum-labels .hi { color: var(--text-3); }

/* step accordion */
.step-accordion {
  display: flex; flex-direction: column; gap: 6px;
  margin-top: 4px;
}
.step-accordion summary {
  cursor: pointer; color: var(--text-2); font-weight: 600; font-size: 0.8125rem;
  padding: 6px 0; list-style: none; display: flex; align-items: center; gap: 6px;
  user-select: none;
}
.step-accordion summary::-webkit-details-marker { display: none; }
.step-accordion summary::before {
  content: '▶'; font-size: 0.6rem; color: var(--text-3);
  transition: transform .15s ease;
}
.step-accordion[open] summary::before { transform: rotate(90deg); }
.step-list {
  display: flex; flex-direction: column; gap: 8px;
  padding: 10px 0 4px 16px;
  border-left: 2px solid var(--border);
  margin-left: 5px;
}
.step-item {
  display: grid; grid-template-columns: 20px 1fr; gap: 8px; align-items: start;
}
.step-item .n {
  display: inline-flex; align-items: center; justify-content: center;
  width: 20px; height: 20px; border-radius: 6px;
  background: var(--amber-soft); color: var(--amber-2);
  font-size: 0.6875rem; font-weight: 700;
  border: 1px solid var(--amber-border);
  margin-top: 1px;
}
.step-item .body { display: flex; flex-direction: column; gap: 2px; }
.step-item .lbl { font-size: 0.8125rem; color: var(--text-2); font-weight: 500; }
.step-item .eq  {
  font-family: ui-monospace, SFMono-Regular, "SF Mono", Menlo, Consolas, monospace;
  font-size: 0.8125rem; color: var(--text);
  background: var(--bg-2); border: 1px solid var(--border);
  border-radius: 6px; padding: 5px 10px;
  display: flex; gap: 6px; flex-wrap: wrap; align-items: center;
}
.step-item .eq .k { color: var(--amber); }
.step-item .eq .v { color: var(--text); font-weight: 600; }
.step-item .eq .r { color: var(--amber-2); font-weight: 700; }

/* mobile fixed bottom bar */
.mobile-bar {
  display: none;
  position: fixed; bottom: 0; left: 0; right: 0;
  background: var(--surface);
  border-top: 1px solid var(--border);
  padding: 12px 20px;
  z-index: 50;
  cursor: pointer;
  box-shadow: 0 -8px 32px rgba(0,0,0,0.4);
}
.mobile-bar-inner {
  display: flex; justify-content: space-between; align-items: center;
}
.mobile-bar .range-label { font-size: 0.75rem; color: var(--text-3); font-weight: 600; text-transform: uppercase; letter-spacing: 0.08em; }
.mobile-bar .range-val { font-size: 1.25rem; font-weight: 800; letter-spacing: -0.02em; }
.mobile-bar .tap-hint { font-size: 0.6875rem; color: var(--text-3); }
.mobile-bar-details {
  display: none;
  margin-top: 12px;
  padding-top: 12px;
  border-top: 1px solid var(--border);
  max-height: 60vh; overflow-y: auto;
}
.mobile-bar-expanded .mobile-bar-details { display: block; }
.mobile-bar-expanded .tap-hint { display: none; }
@media (max-width: 639px) {
  .mobile-bar { display: block; }
  .output { padding-bottom: 80px; }
}

/* form */
.form {
  background: var(--surface);
  border: 1px solid var(--border);
  border-radius: var(--radius);
  padding: 24px;
  display: flex; flex-direction: column; gap: 22px;
}
.field { display: flex; flex-direction: column; gap: 8px; }
.field label { font-weight: 600; font-size: 0.875rem; color: var(--text); }
.field .hint { font-size: 0.8125rem; color: var(--text-3); }

.input, .select {
  width: 100%;
  background: var(--bg-2);
  border: 1px solid var(--border-2);
  border-radius: var(--radius-sm);
  padding: 12px 14px;
  color: var(--text);
  font-size: 0.9375rem;
  transition: border-color .12s ease, box-shadow .12s ease;
}
.input:focus, .select:focus {
  outline: none;
  border-color: var(--amber);
  box-shadow: 0 0 0 3px var(--amber-soft);
}

input[type="number"]::-webkit-inner-spin-button,
input[type="number"]::-webkit-outer-spin-button { -webkit-appearance: none; }
input[type="number"] { -moz-appearance: textfield; }

/* range slider with number display */
.range-row { display: flex; align-items: center; gap: 12px; }
.range-row .input { width: 110px; text-align: right; }
input[type="range"] {
  -webkit-appearance: none; appearance: none;
  flex: 1; height: 6px; border-radius: 3px;
  background: linear-gradient(90deg, var(--amber) var(--p,0%), var(--border-2) var(--p,0%));
  outline: none;
}
input[type="range"]::-webkit-slider-thumb {
  -webkit-appearance: none; appearance: none;
  width: 18px; height: 18px; border-radius: 50%;
  background: var(--amber-2); border: 2px solid var(--bg);
  box-shadow: 0 0 0 1px var(--amber-border);
  cursor: pointer;
}
input[type="range"]::-moz-range-thumb {
  width: 18px; height: 18px; border-radius: 50%;
  background: var(--amber-2); border: 2px solid var(--bg);
  box-shadow: 0 0 0 1px var(--amber-border);
  cursor: pointer;
}

/* forensic field note */
.field-note {
  background: var(--bg-2);
  border: 1px solid var(--amber-border);
  border-left: 4px solid var(--amber);
  border-radius: var(--radius-sm);
  padding: 14px;
  margin-top: 16px;
  font-size: 0.875rem;
  line-height: 1.5;
  color: var(--text-2);
}
.field-note strong {
  color: var(--amber-2);
  display: block;
  font-size: 0.7rem;
  text-transform: uppercase;
  letter-spacing: 0.05em;
  margin-bottom: 4px;
}

.options { display: grid; gap: 10px; grid-template-columns: repeat(auto-fit, minmax(120px, 1fr)); }
.opt {
  position: relative;
  display: flex; flex-direction: column; gap: 4px;
  padding: 12px 14px;
  background: var(--bg-2);
  border: 1px solid var(--border-2);
  border-radius: var(--radius-sm);
  cursor: pointer;
  transition: border-color .12s ease, background .12s ease;
  user-select: none;
}
.opt:hover { border-color: var(--amber-border); }
.opt input {
  position: absolute;
  inset: 0;
  width: 100%;
  height: 100%;
  opacity: 0;
  margin: 0;
  cursor: pointer;
  z-index: 1;
}
.opt .opt-label { font-weight: 600; font-size: 0.9375rem; position: relative; z-index: 0; }
.opt .opt-sub   { font-size: 0.75rem; color: var(--text-3); position: relative; z-index: 0; }
.opt:has(input:checked) {
  border-color: var(--amber);
  background: linear-gradient(180deg, rgba(245,158,11,0.06), rgba(245,158,11,0.02));
}
.opt:has(input:checked) .opt-label { color: var(--amber-2); }

/* output panel */
.output {
  background: var(--surface);
  border: 1px solid var(--border);
  border-radius: var(--radius);
  padding: 24px;
  position: sticky; top: 84px;
  display: flex; flex-direction: column; gap: 18px;
}
.output .total {
  display: flex; flex-direction: column; gap: 4px;
  padding-bottom: 16px; border-bottom: 1px solid var(--border);
}
.output .total .label { font-size: 0.75rem; font-weight: 700; letter-spacing: 0.12em; text-transform: uppercase; color: var(--text-3); }
.output .total .value {
  font-size: clamp(1.875rem, 4vw, 2.5rem);
  font-weight: 800; letter-spacing: -0.025em;
  font-variant-numeric: tabular-nums;
}
.output .total .range { color: var(--text-2); font-size: 0.875rem; }

.bands { display: grid; grid-template-columns: 1fr 1fr 1fr; gap: 10px; }
.band {
  background: var(--bg-2);
  border: 1px solid var(--border);
  border-radius: var(--radius-sm);
  padding: 12px;
  text-align: center;
}
.band .band-label { font-size: 0.6875rem; font-weight: 700; letter-spacing: 0.1em; text-transform: uppercase; color: var(--text-3); }
.band .band-value { font-weight: 700; font-size: 1.0625rem; margin-top: 4px; font-variant-numeric: tabular-nums; }
.band.is-mid { border-color: var(--amber-border); background: var(--amber-soft); }
.band.is-mid .band-label { color: var(--amber-2); }

.breakdown { display: flex; flex-direction: column; gap: 10px; }
.breakdown .row {
  display: flex; justify-content: space-between; align-items: center;
  padding: 10px 12px; background: var(--bg-2);
  border: 1px solid var(--border); border-radius: var(--radius-sm);
  font-size: 0.9375rem;
}
.breakdown .row .name { color: var(--text-2); }
.breakdown .row .val  { font-weight: 600; font-variant-numeric: tabular-nums; }

.output .meta {
  display: flex; flex-wrap: wrap; gap: 8px 14px;
  font-size: 0.75rem; color: var(--text-3);
  padding-top: 12px; border-top: 1px solid var(--border);
}
.output .assumptions { font-size: 0.8125rem; color: var(--text-3); }
.output .assumptions summary,
.output .provenance summary { cursor: pointer; color: var(--text-2); font-weight: 600; padding: 6px 0; }
.output .assumptions ul,
.output .provenance ul { padding: 8px 0 0 18px; display: flex; flex-direction: column; gap: 4px; }

.prov-item {
  display: flex;
  flex-direction: column;
  gap: 2px;
  padding: 8px 0;
  border-bottom: 1px solid var(--border);
  font-size: 0.8125rem;
}
.prov-item:last-child { border-bottom: 0; }
.prov-name { color: var(--text); font-weight: 600; }
.prov-type { font-size: 0.7rem; text-transform: uppercase; color: var(--amber); font-weight: 700; }
.prov-detail { color: var(--text-3); font-style: italic; }

/* validation loop */
.validation {
  margin-top: 20px;
  padding-top: 16px;
  border-top: 1px solid var(--border);
  display: flex;
  flex-direction: column;
  gap: 12px;
}
.val-text {
  font-size: 0.8125rem;
  font-weight: 600;
  color: var(--text);
  text-align: center;
}
.val-btns {
  display: flex;
  gap: 8px;
  justify-content: center;
}
.val-btns .btn.verified {
  border-color: var(--success);
  color: var(--success);
  cursor: default;
}


/* =========================================================
   Methodology page
   ========================================================= */

.article {
  max-width: 760px;
  margin: 0 auto;
  padding: 56px 24px 80px;
}
.article-wide { max-width: 920px; }

.article-hero { text-align: center; padding-bottom: 40px; border-bottom: 1px solid var(--border); }
.article-hero h1 { margin: 12px auto 16px; max-width: 22ch; }
.article-hero .lead { margin: 0 auto; }
.article-meta {
  display: inline-flex; flex-wrap: wrap; gap: 6px 16px; justify-content: center;
  margin-top: 24px; font-size: 0.8125rem; color: var(--text-3);
}
.article-meta strong { color: var(--text-2); font-weight: 600; }
.article-meta .dot { color: var(--border-2); }

.article-section { padding: 48px 0; border-bottom: 1px solid var(--border); }
.article-section:last-of-type { border-bottom: 0; }
.article-section h2 { margin-bottom: 16px; }
.article-section p  { color: var(--text-2); margin-bottom: 14px; }
.article-section p:last-child { margin-bottom: 0; }
.article-section ul { color: var(--text-2); padding-left: 22px; display: flex; flex-direction: column; gap: 8px; margin-bottom: 14px; }
.article-section strong { color: var(--text); font-weight: 600; }

/* short-version (TL;DR) box */
.tldr {
  background: var(--surface);
  border: 1px solid var(--amber-border);
  border-left: 3px solid var(--amber);
  border-radius: var(--radius);
  padding: 22px 24px;
  display: flex; flex-direction: column; gap: 10px;
  margin: 24px 0;
}
.tdlr-label {
  font-size: 0.6875rem; font-weight: 700; letter-spacing: 0.14em;
  text-transform: uppercase; color: var(--amber);
}
.tldr p { color: var(--text); font-size: 1rem; line-height: 1.6; margin: 0; }

/* formula / code blocks */
.formula {
  background: var(--bg-2);
  border: 1px solid var(--border);
  border-radius: var(--radius);
  padding: 20px 22px;
  font-family: ui-monospace, SFMono-Regular, "SF Mono", Menlo, Consolas, monospace;
  font-size: 0.9375rem;
  color: var(--text);
  overflow-x: auto;
  margin: 18px 0;
  line-height: 1.7;
}
.formula .var { color: var(--amber-2); }
.formula .op  { color: var(--text-3); }
.formula .res { color: var(--success); font-weight: 700; }

/* step-by-step sample calculation */
.calc-steps { display: flex; flex-direction: column; gap: 12px; margin: 20px 0; }
.calc-step {
  display: grid; grid-template-columns: 28px 1fr; gap: 14px;
  background: var(--surface);
  border: 1px solid var(--border);
  border-radius: var(--radius-sm);
  padding: 14px 16px;
}
.calc-step .n {
  display: inline-flex; align-items: center; justify-content: center;
  width: 28px; height: 28px; border-radius: 8px;
  background: var(--amber-soft); color: var(--amber-2);
  font-weight: 700; font-size: 0.8125rem;
  border: 1px solid var(--amber-border);
}
.calc-step .body { display: flex; flex-direction: column; gap: 4px; }
.calc-step .body .lbl { color: var(--text); font-weight: 600; font-size: 0.9375rem; }
.calc-step .body .eq  { color: var(--text-2); font-size: 0.875rem; font-family: ui-monospace, SFMono-Regular, "SF Mono", Menlo, Consolas, monospace; }
.calc-step .body .out { color: var(--amber-2); font-weight: 700; font-variant-numeric: tabular-nums; font-size: 0.9375rem; }

/* data tables (sources, midpoints) */
.data-table {
  width: 100%;
  border-collapse: collapse;
  margin: 18px 0;
  font-size: 0.9375rem;
  background: var(--surface);
  border: 1px solid var(--border);
  border-radius: var(--radius);
  overflow: hidden;
}
.data-table th, .data-table td {
  padding: 12px 16px;
  text-align: left;
  border-bottom: 1px solid var(--border);
}
.data-table thead th {
  background: var(--bg-2);
  font-size: 0.75rem;
  font-weight: 700;
  letter-spacing: 0.08em;
  text-transform: uppercase;
  color: var(--text-3);
}
.data-table tbody tr:last-child td { border-bottom: 0; }
.data-table tbody tr:hover { background: var(--bg-2); }
.data-table td.num { text-align: right; font-variant-numeric: tabular-nums; font-weight: 600; }
.data-table td a { color: var(--amber-2); }

/* source cards (compact reference list) */
.sources-grid {
  display: grid; gap: 10px;
  grid-template-columns: 1fr;
  margin: 18px 0;
}
@media (min-width: 640px) { .sources-grid { grid-template-columns: 1fr 1fr; } }
.source-card {
  background: var(--surface);
  border: 1px solid var(--border);
  border-radius: var(--radius-sm);
  padding: 12px 14px;
  display: flex; flex-direction: column; gap: 4px;
  transition: border-color .12s ease;
}
.source-card:hover { border-color: var(--amber-border); }
.source-card .name { color: var(--text); font-weight: 600; font-size: 0.9375rem; }
.source-card .name a { color: var(--text); }
.source-card .name a:hover { color: var(--amber-2); text-decoration: none; }
.source-card .kind { font-size: 0.6875rem; font-weight: 700; letter-spacing: 0.1em; text-transform: uppercase; color: var(--text-3); }
.source-card .kind.gov     { color: #60a5fa; }
.source-card .kind.industry{ color: var(--amber-2); }
.source-card .kind.media   { color: var(--text-2); }

/* pill list (key data points) */
.facts { display: grid; gap: 12px; grid-template-columns: 1fr; margin: 18px 0; }
@media (min-width: 640px) { .facts { grid-template-columns: 1fr 1fr 1fr; } }
.fact {
  background: var(--bg-2);
  border: 1px solid var(--border);
  border-radius: var(--radius-sm);
  padding: 16px;
  display: flex; flex-direction: column; gap: 4px;
}
.fact .v {
  font-size: 1.5rem; font-weight: 800; letter-spacing: -0.02em;
  color: var(--amber-2);
  font-variant-numeric: tabular-nums;
}
.fact .k { font-size: 0.8125rem; color: var(--text-2); }

/* limitations / honest list */
.limits { display: flex; flex-direction: column; gap: 10px; margin: 16px 0; }
.limit {
  display: grid; grid-template-columns: 24px 1fr; gap: 12px;
  padding: 12px 14px;
  background: var(--bg-2);
  border: 1px solid var(--border);
  border-radius: var(--radius-sm);
}
.limit .x {
  display: inline-flex; align-items: center; justify-content: center;
  width: 22px; height: 22px; border-radius: 6px;
  background: rgba(239, 68, 68, 0.10); color: #f87171;
  font-weight: 700; font-size: 0.75rem;
  border: 1px solid rgba(239, 68, 68, 0.25);
  margin-top: 1px;
}
.limit .body { display: flex; flex-direction: column; gap: 2px; }
.limit .body .t { color: var(--text); font-weight: 600; font-size: 0.9375rem; }
.limit .body .d { color: var(--text-2); font-size: 0.875rem; }

.limit.is-included .x {
  background: var(--success-soft); color: var(--success);
  border-color: rgba(16, 185, 129, 0.25);
}
/* ----- next steps / topic cluster ----- */
.next-steps {
  display: flex;
  flex-direction: column;
  gap: 8px;
  padding-top: 16px;
  border-top: 1px solid var(--border);
  margin-top: 4px;
}
.next-steps-title {
  font-size: 0.7rem;
  font-weight: 700;
  letter-spacing: 0.12em;
  text-transform: uppercase;
  color: var(--text-3);
  margin-bottom: 2px;
}
.next-step {
  display: flex;
  flex-direction: column;
  gap: 1px;
  padding: 10px 12px;
  background: var(--bg-2);
  border: 1px solid var(--border);
  border-radius: var(--radius-sm);
  text-decoration: none;
  transition: border-color .12s ease;
}
.next-step:hover {
  border-color: var(--amber-border);
  text-decoration: none;
}
.next-step-label {
  font-weight: 600;
  font-size: 0.875rem;
  color: var(--amber-2);
}
.next-step-desc {
  font-size: 0.75rem;
  color: var(--text-3);
}

/* ----- ad slots ----- */
.ad-slot {
  background: var(--bg-2);
  border: 1px solid var(--border);
  border-radius: var(--radius-sm);
  padding: 12px;
  text-align: center;
  display: flex;
  flex-direction: column;
  gap: 8px;
  margin: 10px 0;
}
.ad-label {
  font-size: 0.65rem;
  font-weight: 700;
  text-transform: uppercase;
  color: var(--text-3);
  align-self: flex-start;
  letter-spacing: 0.05em;
}
.ad-content {
  font-size: 0.875rem;
  color: var(--text-2);
  padding: 16px 0;
  border: 1px dashed var(--border-2);
  border-radius: 4px;
}

/* CTA footer block */
.cta-block {
  text-align: center;
  padding: 48px 24px 0;
  display: flex; flex-direction: column; align-items: center; gap: 16px;
}
.cta-block p { color: var(--text-2); max-width: 48ch; }

/* small variant - inline band inline visual */
.band-vis {
  display: grid; grid-template-columns: 1fr 1.4fr 1fr; gap: 8px;
  margin: 18px 0;
  align-items: stretch;
}
.band-vis .seg {
  background: var(--bg-2);
  border: 1px solid var(--border);
  border-radius: var(--radius-sm);
  padding: 14px;
  text-align: center;
}
.band-vis .seg .lbl { font-size: 0.6875rem; font-weight: 700; letter-spacing: 0.1em; text-transform: uppercase; color: var(--text-3); }
.band-vis .seg .v   { font-weight: 800; font-size: 1.125rem; margin-top: 4px; font-variant-numeric: tabular-nums; }
.band-vis .seg.mid  { background: var(--amber-soft); border-color: var(--amber-border); }
.band-vis .seg.mid .lbl { color: var(--amber); }
.band-vis .seg.mid .v   { color: var(--amber-2); }

/* anchor nav for the article */
.toc {
  display: flex; flex-wrap: wrap; gap: 6px 14px;
  justify-content: center;
  padding: 16px 0 0;
  font-size: 0.8125rem;
}
.toc a { color: var(--text-2); }
.toc a:hover { color: var(--amber-2); text-decoration: none; }

/* stacked band visualization (Roofing + Concrete rows) */
.band-row {
  display: flex; align-items: center; gap: 14px;
  margin: 10px 0;
}
.band-row .band-name {
  font-weight: 700; color: var(--amber-2);
  min-width: 84px; font-size: 0.875rem;
  letter-spacing: 0.04em;
  text-transform: uppercase;
}
.band-row .band-vis { flex: 1; margin: 0; }
@media (max-width: 600px) {
  .band-row { flex-direction: column; align-items: stretch; }
  .band-row .band-name { margin-bottom: 6px; }
}

/* ----- depth section (factors grid) ----- */
.depth-section {
  max-width: 720px;
  margin: 0 auto;
}
.depth-grid {
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: 16px;
}
@media (max-width: 600px) {
  .depth-grid { grid-template-columns: 1fr; }
}
.depth-item {
  display: flex;
  gap: 10px;
  align-items: flex-start;
  font-size: 0.85rem;
  line-height: 1.55;
  color: var(--text-2);
}
.depth-item strong {
  color: var(--text);
  font-weight: 600;
}
/* ----- city-table (regional pages) ----- */
.city-table {
  width: 100%;
  border-collapse: collapse;
  font-size: 0.85rem;
  background: var(--surface);
  border-radius: var(--radius-sm);
  overflow: hidden;
}
.city-table thead {
  background: var(--surface-2);
}
.city-table th {
  text-align: left;
  padding: 10px 14px;
  font-weight: 600;
  color: var(--text);
  border-bottom: 1px solid var(--border);
}
.city-table td {
  padding: 10px 14px;
  border-bottom: 1px solid var(--border);
  color: var(--text-2);
}
.city-table tbody tr:last-child td {
  border-bottom: none;
}
.city-table tbody tr:hover {
  background: var(--amber-soft);
}
@media (max-width: 600px) {
  .city-table { font-size: 0.8rem; }
  .city-table th,
  .city-table td { padding: 8px 10px; }
}

/* ----- region links grid ----- */
.region-grid {
  display: flex;
  flex-wrap: wrap;
  gap: 12px;
  margin-top: 16px;
  justify-content: center;
}
@media (max-width: 600px) {
  .region-grid { flex-direction: column; }
}
.region-link {
  display: flex;
  flex-direction: column;
  gap: 4px;
  padding: 14px 16px;
  background: var(--surface);
  border: 1px solid var(--border);
  border-radius: var(--radius-sm);
  text-decoration: none;
  transition: border-color 0.2s, background 0.2s;
  flex: 1 1 calc(50% - 12px);
  min-width: 260px;
}
.region-link:hover {
  border-color: var(--amber-border);
  background: var(--amber-soft);
}
.region-link .region-city {
  font-weight: 600;
  font-size: 0.9rem;
  color: var(--text);
}
.region-link .region-desc {
  font-size: 0.8rem;
  color: var(--text-3);
  line-height: 1.4;
}

.depth-num {
  flex-shrink: 0;
  width: 24px;
  height: 24px;
  border-radius: 50%;
  background: var(--amber-soft);
  border: 1px solid var(--amber-border);
  color: var(--amber-2);
  font-size: 0.75rem;
  font-weight: 700;
  display: flex;
  align-items: center;
  justify-content: center;
  margin-top: 2px;
}

/* ----- footer ----- */
.footer {
  border-top: 1px solid var(--border);
  padding: 40px 0 32px;
  margin-top: 64px;
}
.footer-inner {
  max-width: var(--maxw);
  margin: 0 auto;
  padding: 0 24px;
  display: grid;
  grid-template-columns: 1fr;
  gap: 28px;
}
@media (min-width: 640px) {
  .footer-inner {
    grid-template-columns: 1fr 2fr;
    gap: 40px;
  }
}
.footer-brand {
  font-weight: 800;
  font-size: 1rem;
  color: var(--text);
  letter-spacing: -0.02em;
}
.footer-nav {
  display: flex;
  flex-wrap: wrap;
  gap: 6px 20px;
  align-content: flex-start;
}
.footer-nav a {
  color: var(--text-2);
  font-size: 0.875rem;
  text-decoration: none;
  padding: 4px 0;
  transition: color 0.15s;
}
.footer-nav a:hover {
  color: var(--amber-2);
}
.footer-bottom {
  grid-column: 1 / -1;
  padding-top: 20px;
  border-top: 1px solid var(--border);
  display: flex;
  flex-wrap: wrap;
  gap: 8px 24px;
  font-size: 0.8125rem;
  color: var(--text-3);
}

/* calculator page: h2 sits above the 2-col form/output */
.calc-grid > .calc-h2 {
  grid-column: 1 / -1;
}