/* ============================================================
   NestScore — methodology page (how-it-works.html)
   Loaded after assets/styles.css. Owns the centered hero, 3-step
   intro, score bands, the 13 factor cards (+TOC rail), default
   weights breakdown, distance/coverage block, and data-sources
   table. Tokens, nav, and footer come from styles.css.
   ============================================================ */

/* ── Marketing-page reset ── */
*, *::before, *::after { margin: 0; padding: 0; }
body { font-size: 16px; line-height: 1.6; overflow-x: hidden; }

/* ── Section-sub width override (global default has no max-width) ── */
.section-sub { max-width: 640px; }

/* ── Section spacing ── */
section { padding: 100px 24px; }

/* ── Hero ── */
.hero {
  padding: 140px 24px 80px;
  position: relative; overflow: hidden;
  border-bottom: 1px solid var(--border);
}
.hero::before {
  content: ''; position: absolute; inset: 0; z-index: 0;
  background-image: radial-gradient(circle, rgba(31,77,63,0.10) 1.5px, transparent 1.5px);
  background-size: 28px 28px;
  mask-image: radial-gradient(ellipse 80% 80% at 50% 30%, black 30%, transparent 80%);
}
.hero-inner {
  max-width: 880px; margin: 0 auto; position: relative; z-index: 1;
  text-align: center;
}
.hero-eyebrow {
  display: inline-flex; align-items: center; gap: 8px;
  font-family: var(--font-mono); font-size: 12px; font-weight: 500;
  letter-spacing: 0.08em; text-transform: uppercase; color: var(--moss);
  background: var(--moss-050); border: 1px solid var(--moss-100);
  border-radius: 9999px; padding: 4px 12px; margin-bottom: 28px;
}
.hero-headline {
  font-size: clamp(36px, 5vw, 60px);
  font-weight: 600; letter-spacing: -0.03em; line-height: 1.05;
  color: var(--ink); margin-bottom: 24px;
}
.hero-headline .serif {
  font-family: var(--font-serif); font-style: italic; font-weight: 400; color: var(--moss);
}
.hero-sub {
  font-size: 18px; line-height: 1.65;
  color: var(--ink-500); max-width: 580px;
  margin: 0 auto 40px;
}
.hero-cta { display: flex; align-items: center; justify-content: center; gap: 14px; flex-wrap: wrap; }

.btn-primary {
  height: 52px; padding: 0 28px;
  background: var(--moss); color: var(--paper);
  border: none; border-radius: 10px;
  font-family: var(--font-sans); font-size: 16px; font-weight: 600;
  cursor: pointer; text-decoration: none;
  display: inline-flex; align-items: center; gap: 8px;
  transition: background 200ms var(--ease), transform 150ms var(--ease), box-shadow 200ms var(--ease);
  box-shadow: 0 4px 14px rgba(31,77,63,0.30);
}
.btn-primary:hover { background: var(--moss-700); transform: translateY(-1px); box-shadow: 0 6px 20px rgba(31,77,63,0.38); }
.btn-secondary {
  height: 52px; padding: 0 28px;
  background: transparent; color: var(--ink-700);
  border: 1.5px solid var(--border-strong); border-radius: 10px;
  font-family: var(--font-sans); font-size: 16px; font-weight: 500;
  cursor: pointer; text-decoration: none;
  display: inline-flex; align-items: center; gap: 8px;
  transition: all 200ms var(--ease);
}
.btn-secondary:hover { background: var(--paper-lift); border-color: var(--moss-300); color: var(--moss); }

/* ── 3-step grid ── */
.how {
  background: var(--paper-lift);
  border-bottom: 1px solid var(--border);
}
.how-header { text-align: center; max-width: 720px; margin: 0 auto 64px; }
.how-header .section-sub { margin: 0 auto; }
.how-steps {
  display: grid; grid-template-columns: repeat(3, 1fr); gap: 2px;
  background: var(--border); border-radius: 16px; overflow: hidden;
  box-shadow: var(--shadow-1);
}
.how-step {
  background: var(--paper-lift); padding: 40px 36px;
  position: relative; overflow: hidden;
}
.how-step::before {
  content: ''; position: absolute; top: 0; left: 0; right: 0; height: 3px;
  background: var(--moss); transform: scaleX(0); transform-origin: left;
  transition: transform 400ms var(--ease);
}
.how-step:hover::before { transform: scaleX(1); }
.step-number {
  font-family: var(--font-mono); font-size: 11px; font-weight: 600;
  letter-spacing: 0.1em; text-transform: uppercase;
  color: var(--moss); margin-bottom: 20px;
  display: flex; align-items: center; gap: 8px;
}
.step-number::after { content: ''; flex: 1; height: 1px; background: var(--moss-100); }
.step-icon { font-size: 32px; margin-bottom: 16px; display: block; filter: saturate(0.8); }
.step-title { font-size: 20px; font-weight: 600; color: var(--ink); margin-bottom: 12px; letter-spacing: -0.01em; }
.step-body { font-size: 15px; line-height: 1.65; color: var(--ink-500); }

/* ── Bands ── */
.bands { background: var(--paper); }
.bands-inner { max-width: 1160px; margin: 0 auto; display: grid; grid-template-columns: 1fr 1fr; gap: 80px; align-items: center; }
.bands-list { display: flex; flex-direction: column; gap: 16px; }
.band-item {
  display: flex; align-items: center; gap: 16px;
  padding: 16px 20px; border-radius: 12px;
  background: var(--paper-lift); border: 1px solid var(--border);
  transition: all 200ms var(--ease); cursor: default;
}
.band-item:hover { transform: translateX(6px); box-shadow: var(--shadow-1); }
.band-score {
  width: 52px; height: 52px; border-radius: 9999px;
  display: flex; align-items: center; justify-content: center;
  font-family: var(--font-mono); font-size: 18px; font-weight: 700;
  color: #F6F1E7; flex-shrink: 0;
}
.band-info { flex: 1; }
.band-label { font-size: 15px; font-weight: 600; color: var(--ink); }
.band-desc { font-size: 13px; color: var(--ink-500); margin-top: 2px; }
.band-range { font-family: var(--font-mono); font-size: 13px; color: var(--ink-300); }

/* ── Factors ── */
.factors {
  background: var(--paper-lift);
  border-top: 1px solid var(--border);
  border-bottom: 1px solid var(--border);
}
.factors-layout {
  max-width: 1160px; margin: 0 auto;
  display: grid; grid-template-columns: 220px 1fr; gap: 56px;
  align-items: start;
}
.toc-rail {
  position: sticky; top: 88px;
  padding: 12px 0;
}
.toc-title {
  font-family: var(--font-mono); font-size: 11px; font-weight: 600;
  letter-spacing: 0.08em; text-transform: uppercase;
  color: var(--ink-500); margin-bottom: 14px;
  padding-bottom: 10px; border-bottom: 1px solid var(--border);
}
.toc-rail ol { list-style: none; padding: 0; margin: 0; counter-reset: toc; }
.toc-rail li { counter-increment: toc; }
.toc-rail a {
  display: flex; align-items: baseline; gap: 8px;
  font-size: 13px; color: var(--ink-500); text-decoration: none;
  padding: 5px 0; line-height: 1.5;
  transition: color 150ms var(--ease);
}
.toc-rail a::before {
  content: counter(toc, decimal-leading-zero);
  font-family: var(--font-mono); font-size: 10px; font-weight: 500;
  color: var(--ink-300); flex-shrink: 0;
}
.toc-rail a:hover { color: var(--moss); }

.factors-header { margin-bottom: 56px; }

.factor-card {
  background: var(--paper); border: 1px solid var(--border);
  border-radius: 16px; padding: 32px;
  margin-bottom: 20px;
  transition: box-shadow 200ms var(--ease);
  scroll-margin-top: 88px;
}
.factor-card:hover { box-shadow: var(--shadow-1); }
.factor-head {
  display: flex; align-items: center; gap: 14px; flex-wrap: wrap;
  margin-bottom: 14px;
}
.factor-icon {
  width: 48px; height: 48px; border-radius: 12px;
  background: var(--moss-050); border: 1px solid var(--moss-100);
  display: flex; align-items: center; justify-content: center;
  font-size: 24px; flex-shrink: 0;
}
.factor-name {
  font-size: 22px; font-weight: 600; letter-spacing: -0.015em;
  color: var(--ink);
}
.weight-badge {
  font-family: var(--font-mono); font-size: 11px; font-weight: 600;
  letter-spacing: 0.06em; text-transform: uppercase;
  color: var(--moss); background: var(--moss-050);
  border: 1px solid var(--moss-100);
  border-radius: 9999px; padding: 4px 10px;
  margin-left: auto;
}
.factor-tagline {
  font-size: 15px; color: var(--ink-500);
  font-style: italic; font-family: var(--font-serif);
  margin-bottom: 18px;
}
.factor-body {
  font-size: 15px; line-height: 1.7; color: var(--ink-700);
  margin-bottom: 18px;
}
.factor-feeds {
  display: flex; flex-wrap: wrap; align-items: baseline;
  gap: 8px; padding-top: 16px; margin-top: 4px;
  border-top: 1px dashed var(--border);
  font-size: 13px;
}
.factor-feeds-label {
  font-family: var(--font-mono); font-size: 11px; font-weight: 600;
  letter-spacing: 0.06em; text-transform: uppercase;
  color: var(--ink-300);
}
.factor-feeds-list { color: var(--ink-500); }

.factor-math {
  margin-top: 16px;
  border-top: 1px dashed var(--border);
}
.factor-math summary {
  list-style: none;
  cursor: pointer;
  padding: 14px 0 0;
  font-family: var(--font-mono); font-size: 12px; font-weight: 500;
  letter-spacing: 0.06em; text-transform: uppercase;
  color: var(--moss);
  display: flex; align-items: center; gap: 8px;
  user-select: none;
}
.factor-math summary::-webkit-details-marker { display: none; }
.factor-math summary::before {
  content: '+';
  width: 18px; height: 18px; border-radius: 4px;
  background: var(--moss); color: var(--paper);
  display: inline-flex; align-items: center; justify-content: center;
  font-size: 14px; font-weight: 700;
  transition: transform 200ms var(--ease);
}
.factor-math[open] summary::before { content: '−'; }
.math-body {
  padding: 16px 16px 4px;
  margin-top: 12px;
  background: var(--paper-lift);
  border: 1px solid var(--border);
  border-radius: 10px;
  font-family: var(--font-mono);
  font-size: 13px;
  line-height: 1.7;
  color: var(--ink-700);
}
.math-body p { margin-bottom: 10px; }
.math-body code { background: var(--paper-dim); padding: 1px 5px; border-radius: 4px; font-size: 12px; }
.math-body ul { margin: 4px 0 10px 20px; }
.math-body li { margin-bottom: 4px; font-size: 12.5px; }

/* ── Weights section ── */
.weights-section { background: var(--paper); }
.weights-inner { max-width: 880px; margin: 0 auto; }
.weights-header { margin-bottom: 56px; text-align: center; }
.weights-header .section-sub { margin: 0 auto; }

.weight-list {
  background: var(--paper-lift);
  border: 1px solid var(--border);
  border-radius: 16px;
  padding: 12px 8px;
  margin-bottom: 56px;
  box-shadow: var(--shadow-1);
}
.weight-row {
  display: grid;
  grid-template-columns: 32px 140px 1fr 56px;
  align-items: center;
  gap: 14px;
  padding: 10px 16px;
  border-radius: 8px;
  transition: background 150ms var(--ease);
}
.weight-row:hover { background: var(--paper); }
.weight-row .w-icon { font-size: 18px; text-align: center; }
.weight-row .w-name { font-size: 14px; font-weight: 500; color: var(--ink); }
.weight-row .w-track {
  height: 8px; border-radius: 9999px;
  background: var(--paper-dim); overflow: hidden;
}
.weight-row .w-fill { height: 100%; border-radius: 9999px; }
.weight-row .w-pct {
  font-family: var(--font-mono); font-size: 13px; font-weight: 600;
  color: var(--ink-700); text-align: right;
}
.weight-group-row {
  grid-column: 1 / -1;
  padding: 12px 16px 6px;
  font-family: var(--font-mono); font-size: 11px; font-weight: 600;
  letter-spacing: 0.08em; text-transform: uppercase;
  color: var(--ink-300);
}
.weight-group-row:first-child { padding-top: 4px; }

.tier-grid {
  display: grid; grid-template-columns: 1fr 1fr; gap: 20px;
  margin-top: 12px;
}
.tier-card {
  background: var(--paper-lift); border: 1px solid var(--border);
  border-radius: 14px; padding: 28px;
}
.tier-card.featured {
  border-color: var(--moss);
  box-shadow: 0 4px 24px rgba(31,77,63,0.10), 0 0 0 1px var(--moss);
}
.tier-card-name {
  font-family: var(--font-mono); font-size: 11px; font-weight: 600;
  letter-spacing: 0.08em; text-transform: uppercase;
  color: var(--ink-500); margin-bottom: 10px;
}
.tier-card.featured .tier-card-name { color: var(--moss); }
.tier-card-headline {
  font-size: 18px; font-weight: 600; color: var(--ink);
  margin-bottom: 12px; letter-spacing: -0.01em;
}
.tier-card-body { font-size: 14px; line-height: 1.65; color: var(--ink-500); }

.weights-cta {
  margin-top: 40px;
  display: flex; gap: 14px; justify-content: center; flex-wrap: wrap;
}

/* ── Distance & coverage ── */
.distance {
  background: var(--paper-lift);
  border-top: 1px solid var(--border);
  border-bottom: 1px solid var(--border);
}
.distance-inner {
  max-width: 880px; margin: 0 auto;
  display: grid; grid-template-columns: 1fr; gap: 32px;
}
.distance-grid {
  display: grid; grid-template-columns: 1fr 1fr; gap: 20px;
  margin-top: 32px;
}
.distance-card {
  background: var(--paper); border: 1px solid var(--border);
  border-radius: 14px; padding: 28px;
}
.distance-card h3 {
  font-size: 17px; font-weight: 600; color: var(--ink);
  margin-bottom: 10px; letter-spacing: -0.01em;
}
.distance-card p {
  font-size: 14px; line-height: 1.65; color: var(--ink-500);
}

/* ── Data sources ── */
.data-section { background: var(--paper); }
.data-inner { max-width: 1000px; margin: 0 auto; }
.data-header { margin-bottom: 48px; text-align: center; }
.data-header .section-sub { margin: 0 auto; }
.data-table {
  width: 100%; border-collapse: collapse;
  background: var(--paper-lift);
  border: 1px solid var(--border);
  border-radius: 14px; overflow: hidden;
  box-shadow: var(--shadow-1);
}
.data-table th, .data-table td {
  text-align: left; padding: 14px 20px;
  font-size: 14px; line-height: 1.55;
  border-bottom: 1px solid var(--border);
}
.data-table th {
  font-family: var(--font-mono); font-size: 11px; font-weight: 600;
  letter-spacing: 0.08em; text-transform: uppercase;
  color: var(--ink-500); background: var(--paper-dim);
}
.data-table tr:last-child td { border-bottom: none; }
.data-table td:first-child { font-weight: 600; color: var(--ink); }
.data-table td:nth-child(2) { color: var(--ink-500); }
.data-table td:nth-child(3) { color: var(--ink-500); font-family: var(--font-mono); font-size: 12.5px; }
.data-note {
  margin-top: 28px; text-align: center;
  font-family: var(--font-serif); font-style: italic;
  font-size: 16px; color: var(--ink-500);
}

/* ── Responsive ── */
@media (max-width: 900px) {
  .how-steps { grid-template-columns: 1fr; }
  .bands-inner { grid-template-columns: 1fr; gap: 48px; }
  .factors-layout { grid-template-columns: 1fr; gap: 32px; }
  .toc-rail { position: relative; top: 0; padding: 16px 20px;
    background: var(--paper); border: 1px solid var(--border); border-radius: 12px; }
  .toc-rail ol { columns: 2; column-gap: 24px; }
  .tier-grid, .distance-grid { grid-template-columns: 1fr; }
}
@media (max-width: 600px) {
  .factor-card { padding: 24px 20px; }
  .factor-head { gap: 10px; }
  .weight-badge { margin-left: 0; }
  .data-table th, .data-table td { padding: 12px 14px; font-size: 13px; }
  .data-table td:nth-child(3) { font-size: 11.5px; }
  .toc-rail ol { columns: 1; }
}
@media (max-width: 480px) {
  .hero { padding: 110px 20px 60px; }
  section { padding: 72px 20px; }
  .factor-card { padding: 22px 18px; scroll-margin-top: 76px; }
  .factor-head { gap: 10px; }
  .factor-icon { width: 40px; height: 40px; font-size: 20px; }
  .factor-name { font-size: 19px; }
  .weight-badge { margin-left: 0; flex-basis: 100%; align-self: flex-start; }
  .factor-body { font-size: 14px; }
  .math-body { overflow-x: auto; padding: 14px; }
  .math-body p, .math-body li { white-space: normal; word-break: break-word; }
  .toc-rail { padding: 14px 16px; }
  .toc-rail ol { font-size: 12px; }
  .data-table-wrap { overflow-x: auto; -webkit-overflow-scrolling: touch; }
  .data-table { min-width: 520px; }
  .weight-row { grid-template-columns: 28px 110px 1fr 44px; gap: 10px; padding: 8px 12px; }
  .weight-row .w-name { font-size: 13px; }
  .weights-cta .btn-primary, .weights-cta .btn-secondary { height: 46px; padding: 0 20px; font-size: 14px; }
}
.math-body { overflow-x: auto; }