/* ============================================================================
   inner guru — base / reset / type + button primitives (tokens only)
   Type system (per identity v4.0): SANS cut for headlines with selected words in
   the SERIF ITALIC cut; MONO (Google Sans Code) for body, subheads, labels,
   buttons, nav, meta. Wordmark is the serif cut. UI is strictly neutral.
   ============================================================================ */

*, *::before, *::after { box-sizing: border-box; }
* { margin: 0; }

html { -webkit-text-size-adjust: 100%; scroll-behavior: smooth; }

body {
  font-family: var(--font-mono);
  font-size: var(--type-body);
  font-weight: var(--weight-body);
  line-height: var(--leading-body);
  color: var(--text-primary);
  background: var(--surface-page);
  -webkit-font-smoothing: antialiased;
  text-rendering: optimizeLegibility;
}

img, svg, picture { display: block; max-width: 100%; height: auto; }
a { color: inherit; }

:focus-visible {
  outline: 2px solid var(--text-primary);
  outline-offset: 3px;
  border-radius: var(--radius-sm);
}

@media (prefers-reduced-motion: reduce) {
  html { scroll-behavior: auto; }
  *, *::before, *::after {
    animation-duration: 0.001ms !important;
    animation-iteration-count: 1 !important;
    transition-duration: 0.001ms !important;
  }
}

/* --- Layout primitives ----------------------------------------------------- */
.container {
  width: 100%;
  max-width: var(--container-max);
  margin-inline: auto;
  padding-inline: var(--gutter);
}
.section { padding-block: var(--space-3xl); }
.section--tight { padding-block: var(--space-2xl); }
.section--alt { background: var(--surface-alt); }           /* alternating: paper <-> white */
.section--inverse { background: var(--surface-inverse); color: var(--text-on-inverse); }

/* --- Type primitives ------------------------------------------------------- */
/* Headlines: sans cut. Accent words: serif italic (the "two worlds" switch). */
.display {
  font-family: var(--font-sans);
  font-weight: var(--weight-body);
  font-size: var(--type-display);
  line-height: var(--leading-display);
  letter-spacing: var(--tracking-tight);
  text-wrap: balance;
  overflow-wrap: break-word;
}
.display em, .serif-em {
  font-family: var(--font-serif);
  font-style: italic;
  font-weight: 400;
  letter-spacing: 0;
}

.h2 {
  font-family: var(--font-sans);
  font-weight: var(--weight-body);
  font-size: var(--type-h2);
  line-height: var(--leading-snug);
  letter-spacing: var(--tracking-tight);
  text-wrap: balance;
  overflow-wrap: break-word;
}
.h3 {
  font-family: var(--font-sans);
  font-weight: var(--weight-medium);
  font-size: var(--type-h3);
  line-height: var(--leading-snug);
}

/* Subheads / manifesto: mono, muted */
.lede {
  font-family: var(--font-mono);
  font-size: var(--type-lede);
  line-height: 1.55;
  color: var(--text-muted);
  max-width: var(--measure);
  text-wrap: pretty;
}

.body { max-width: var(--measure); }
.body p { overflow-wrap: anywhere; }
.body p + p { margin-top: var(--space-md); }

.eyebrow {
  font-family: var(--font-mono);
  font-size: var(--type-label);
  font-weight: var(--weight-medium);
  text-transform: uppercase;
  letter-spacing: var(--tracking-label);
  color: var(--text-faint);
}

.measure-narrow { max-width: var(--measure-narrow); }

.section-head { display: grid; gap: var(--space-md); max-width: var(--measure); }
.section-head--center { margin-inline: auto; text-align: center; justify-items: center; }

/* --- Wordmark (serif cut) -------------------------------------------------- */
.wordmark {
  font-family: var(--font-serif);
  font-weight: 400;
  line-height: 0.9;
  letter-spacing: var(--tracking-tight);
  text-decoration: none;
  color: currentColor;
  display: inline-block;
}
.wordmark--stacked { font-size: 1.4rem; }

/* --- Buttons (mono, all-caps) ---------------------------------------------- */
.btn {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  gap: var(--space-xs);
  font-family: var(--font-mono);
  font-size: 0.6875rem;
  font-weight: var(--weight-medium);
  text-transform: uppercase;
  letter-spacing: 0.13em;
  text-decoration: none;
  border-radius: var(--radius-pill);
  padding: 0.65em 1.45em;
  cursor: pointer;
  border: var(--border-hairline) solid transparent;
  transition: background var(--dur) var(--ease), color var(--dur) var(--ease),
              border-color var(--dur) var(--ease), transform var(--dur) var(--ease);
}
.btn:active { transform: translateY(1px); }

.btn--primary {
  background: var(--color-ink);
  color: var(--color-paper);
  border-color: var(--color-ink);
}
.btn--primary:hover { background: transparent; color: var(--color-ink); border-color: var(--border-strong); }

.btn--ghost {
  background: transparent;
  color: var(--text-primary);
  border-color: var(--border-strong);
}
.btn--ghost:hover { background: var(--color-ink); color: var(--color-paper); border-color: var(--color-ink); }

/* Inverse sections: invert the primary button */
.section--inverse .btn--primary { background: var(--color-paper); color: var(--color-ink); border-color: var(--color-paper); }
.section--inverse .btn--primary:hover { background: transparent; color: var(--color-paper); border-color: var(--color-paper); }

/* Quiet inline link (mono, underline) */
.link-quiet {
  font-family: var(--font-mono);
  font-weight: var(--weight-medium);
  color: var(--text-primary);
  text-decoration: none;
  border-bottom: var(--border-hairline) solid var(--border-strong);
  padding-bottom: 2px;
  transition: border-color var(--dur) var(--ease), opacity var(--dur) var(--ease);
}
.link-quiet:hover { opacity: 0.6; }

/* --- Utilities ------------------------------------------------------------- */
.visually-hidden {
  position: absolute; width: 1px; height: 1px; padding: 0; margin: -1px;
  overflow: hidden; clip: rect(0 0 0 0); white-space: nowrap; border: 0;
}

/* --- Scroll-reveal (JS adds .is-in; reduced-motion shows immediately) ------ */
.reveal {
  opacity: 0;
  transform: translateY(18px);
  transition: opacity var(--dur-slow) var(--ease), transform var(--dur-slow) var(--ease);
  will-change: opacity, transform;
}
.reveal.is-in { opacity: 1; transform: none; }
@media (prefers-reduced-motion: reduce) {
  .reveal { opacity: 1; transform: none; }
}