/* ============================================================
   Onda — base: reset, typography, layout primitives.
   Reads ONLY --surface-* (tier 2) and non-colour --onda-* tokens.
   Never a --onda-<colour> token directly — see tokens.css header.
   ============================================================ */

*, *::before, *::after { box-sizing: border-box; }
html { -webkit-text-size-adjust: 100%; }
body {
  margin: 0;
  font-family: var(--onda-sans);
  font-size: 16px;
  line-height: 1.6;
  -webkit-font-smoothing: antialiased;
  text-rendering: optimizeLegibility;
}
img, svg, canvas, video { display: block; max-width: 100%; }
a { color: inherit; text-decoration: none; }

@media (prefers-reduced-motion: reduce) {
  *, *::before, *::after {
    animation-duration: .001ms !important;
    animation-iteration-count: 1 !important;
    transition-duration: .001ms !important;
    scroll-behavior: auto !important;
  }
}

:focus-visible {
  outline: 2px solid var(--surface-focus);
  outline-offset: 2px;
}

/* ---- Type ---- */
h1, h2, h3, h4 {
  font-family: var(--onda-display);
  font-weight: 600;
  line-height: 1.08;
  letter-spacing: -.02em;
  margin: 0;
}
h1 { font-size: clamp(2.4rem, 5.2vw, 4.2rem); }
h2 { font-size: clamp(1.7rem, 3.4vw, 2.6rem); max-width: 22ch; }
h3 { font-size: clamp(1.1rem, 1.8vw, 1.32rem); }
p  { margin: 0; max-width: var(--onda-measure); }
.lede {
  font-size: clamp(1rem, 1.4vw, 1.14rem);
  color: var(--surface-text-muted);
  max-width: 56ch;
}

.serif {
  font-family: var(--onda-display);
  font-style: italic;
  color: var(--surface-accent-text);
}

.eyebrow, .kicker {
  display: inline-block;
  font-family: var(--onda-mono);
  font-size: .68rem;
  letter-spacing: .16em;
  text-transform: uppercase;
  color: var(--surface-accent-text);
}

.mono { font-family: var(--onda-mono); }

/* ---- Text/colour utilities (kept deliberately small — reach for a
   proper component class first; these exist so page content never
   needs a style= attribute for a one-off colour or spacing tweak) ---- */
.text-muted { color: var(--surface-text-muted); }
.text-faint { color: var(--surface-text-faint); }
.text-accent { color: var(--surface-accent-text); }
.fs-sm { font-size: .9rem; }
.fs-xs { font-size: .8rem; }
.mt-sm { margin-top: .6rem; }
.mt-md { margin-top: 1rem; }
.mt-lg { margin-top: 1.5rem; }
.mt-xl { margin-top: 2rem; }
.mt-xxl { margin-top: 2.5rem; }
.mb-md { margin-bottom: 1rem; }
.mb-lg { margin-bottom: 1.5rem; }
.col-list { list-style: none; padding: 0; display: flex; flex-direction: column; gap: .85rem; }
.fw-600 { font-weight: 600; }
.eyebrow-block { display: block; }
.section-bg-sunken { background: var(--surface-bg-sunken); }
.section-tint { background: var(--surface-accent-wash); }
.max-w-sm { max-width: 32rem; }
.max-w-md { max-width: 48rem; }
.d-inline-block { display: inline-block; }

/* ---- Layout ---- */
.wrap {
  width: min(100% - 2 * var(--onda-pad), var(--onda-max));
  margin-inline: auto;
}
section { padding-block: var(--onda-section-y); }
.section-y-tight { padding-block: calc(var(--onda-section-y) * .6); }

.stack { display: flex; flex-direction: column; }
.gap-xs  { gap: .5rem; }
.gap-s   { gap: 1rem; }
.gap-m   { gap: 1.75rem; }
.gap-l   { gap: 3rem; }

.grid-2 {
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: clamp(1.5rem, 4vw, 3.5rem);
}
@media (max-width: 860px) {
  .grid-2 { grid-template-columns: 1fr; }
}

/* .cols-3/.cols-4 must come AFTER .grid-2 in the cascade: they're used
   together (class="grid-2 cols-4") to reuse grid-2's display/gap while
   overriding its column count — equal specificity means source order
   decides the winner, and this order is what makes the override apply. */
.cols-3 { grid-template-columns: repeat(3, 1fr); }
.cols-4 { grid-template-columns: repeat(4, 1fr); }
@media (max-width: 860px) {
  .cols-3, .cols-4 { grid-template-columns: 1fr; }
}

.hairline-top    { border-top: 1px solid var(--surface-hairline); }
.hairline-bottom { border-bottom: 1px solid var(--surface-hairline); }

/* ---- Buttons ---- */
.btn {
  display: inline-flex;
  align-items: center;
  gap: .5rem;
  font-family: var(--onda-sans);
  font-size: .92rem;
  font-weight: 600;
  padding: .85rem 1.5rem;
  border-radius: 999px;
  border: 1px solid transparent;
  cursor: pointer;
  transition: transform .18s var(--onda-ease), opacity .18s var(--onda-ease);
}
.btn:hover { transform: translateY(-1px); }
.btn-primary {
  background: var(--surface-btn-fill);
  color: var(--surface-btn-ink);
}
.btn-ghost {
  background: transparent;
  color: var(--surface-text);
  border-color: var(--surface-hairline-strong);
}

/* ---- Cards ---- */
.card {
  background: var(--surface-bg-raised);
  border: 1px solid var(--surface-hairline);
  border-radius: var(--onda-radius);
  padding: clamp(1.25rem, 3vw, 2rem);
}

/* ---- Reading primitives (ported from the playbook's chapter CSS) ---- */
.pull {
  font-family: var(--onda-display);
  font-weight: 500;
  font-size: clamp(1.3rem, 2.4vw, 1.75rem);
  line-height: 1.3;
  max-width: 32ch;
  border-left: 3px solid var(--surface-accent);
  padding-left: 1.25rem;
  margin-block: 1rem;
}
.box {
  background: var(--surface-bg-raised);
  border: 1px solid var(--surface-hairline);
  border-radius: var(--onda-radius-sm);
  padding: 1.25rem 1.5rem;
}
.box.teal {
  background: var(--surface-accent-wash);
  border-color: transparent;
}
.box-k {
  display: block;
  font-family: var(--onda-mono);
  font-size: .68rem;
  letter-spacing: .12em;
  text-transform: uppercase;
  color: var(--surface-accent-text);
  margin-bottom: .5rem;
}

/* ---- Numbered hairline rows (replaces the old rounded-card grid) ---- */
.rows { border-top: 1px solid var(--surface-hairline); }
.row {
  display: grid;
  grid-template-columns: 64px .8fr 1.1fr;
  align-items: baseline;
  gap: 1.5rem;
  padding-block: 1.5rem;
  border-bottom: 1px solid var(--surface-hairline);
}
.row-n {
  font-family: var(--onda-mono);
  color: var(--surface-accent-text);
  font-size: .85rem;
}
.row-name {
  font-family: var(--onda-display);
  font-size: 1.15rem;
}
.row-desc { color: var(--surface-text-muted); }
.row-ex {
  display: block;
  margin-top: .4rem;
  font-family: var(--onda-mono);
  font-size: .78rem;
  color: var(--surface-text-faint);
}
@media (max-width: 640px) {
  .row {
    grid-template-columns: 1fr;
    grid-template-areas: "n" "name" "desc";
    gap: .35rem;
  }
}

/* ---- Metrics band ---- */
.metrics {
  display: grid;
  grid-template-columns: repeat(3, 1fr);
  border-top: 1px solid var(--surface-hairline);
  border-bottom: 1px solid var(--surface-hairline);
}
.metric {
  padding: 2rem 1rem;
  text-align: center;
  border-left: 1px solid var(--surface-hairline);
}
.metric:first-child { border-left: none; }
.metric-num {
  font-family: var(--onda-display);
  font-weight: 600;
  font-size: clamp(2rem, 4.4vw, 3rem);
}
.metric-num i { font-style: italic; color: var(--surface-accent-text); }
/* Modifier for a short phrase instead of a number — must come after
   .metric-num to win the cascade (equal specificity, later rule wins). */
.metric-num.is-phrase { font-size: clamp(1.05rem, 2vw, 1.35rem); }
.metric-label { color: var(--surface-text-muted); font-size: .92rem; margin-top: .35rem; }
@media (max-width: 640px) {
  .metrics { grid-template-columns: 1fr; }
  .metric { border-left: none; border-top: 1px solid var(--surface-hairline); }
  .metric:first-child { border-top: none; }
}

/* ---- FAQ ---- */
.faq-item { border-bottom: 1px solid var(--surface-hairline); }
.faq-item summary {
  cursor: pointer;
  list-style: none;
  display: flex;
  justify-content: space-between;
  align-items: center;
  padding: 1.25rem 0;
  font-family: var(--onda-display);
  font-size: 1.05rem;
}
.faq-item summary::-webkit-details-marker { display: none; }
.faq-item summary::after {
  content: '+';
  font-family: var(--onda-mono);
  transition: transform .2s var(--onda-ease);
  color: var(--surface-accent-text);
}
.faq-item[open] summary::after { transform: rotate(45deg); }
.faq-item p { padding-bottom: 1.25rem; color: var(--surface-text-muted); }

/* ---- Comparison / vs block ---- */
.vs { display: grid; grid-template-columns: 1fr 1fr; gap: 1.25rem; }
.vs-col { padding: 1.5rem; border-radius: var(--onda-radius); }
.vs-col.neutral { background: var(--surface-bg-raised); border: 1px solid var(--surface-hairline); }
.vs-col.onda { background: var(--surface-bg-raised); border-left: 3px solid var(--surface-accent); }
.vs-col li { list-style: none; padding-left: 1.4rem; position: relative; margin-block: .5rem; }
.vs-col.neutral li::before { content: '✕'; position: absolute; left: 0; color: var(--surface-text-faint); }
.vs-col.onda li::before { content: '→'; position: absolute; left: 0; color: var(--surface-accent-text); }
@media (max-width: 700px) { .vs { grid-template-columns: 1fr; } }

/* ---- Case card ---- */
.case-card { border: 1px solid var(--surface-hairline); border-radius: var(--onda-radius); padding: 1.5rem; background: var(--surface-bg-raised); }
.case-tag { font-family: var(--onda-mono); font-size: .68rem; letter-spacing: .1em; text-transform: uppercase; color: var(--surface-accent-text); }
.case-row { display: flex; justify-content: space-between; border-top: 1px solid var(--surface-hairline); padding-block: .6rem; }
.case-row i { font-style: normal; color: var(--surface-accent-text); }
.case-foot { border-top: 1px solid var(--surface-hairline-strong); padding-top: .75rem; margin-top: .5rem; font-weight: 600; }