/* ===========================================================================
   Commonplace product site — layout layer
   Sits on top of commonplace.css (the House Style). Adds page structure only;
   all colour, type, shape, and motion come from the House Style tokens.
   =========================================================================== */

/* --- skip link ------------------------------------------------------------- */
.skip-link {
  position: absolute;
  left: -9999px;
  top: 0;
  padding: var(--space-sm) var(--space-lg);
  background: var(--bg-color);
  border: var(--hairline) solid var(--border-color);
  z-index: 100;
}
.skip-link:focus { left: var(--container-pad); top: var(--container-pad); }

/* --- shared page rail ------------------------------------------------------ */
.page-measure { max-width: var(--max-width); margin-inline: auto; padding-inline: var(--container-pad); }

/* --- header ---------------------------------------------------------------- */
.site-header {
  position: sticky;
  top: 0;
  z-index: 50;
  background: var(--bg-color);
  border-bottom: var(--hairline) solid var(--border-color);
}
.site-header .inner {
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: var(--space-lg);
  min-height: 3.5rem;
}
.wordmark {
  font-weight: 700;
  text-transform: uppercase;
  letter-spacing: 0.16em;
  font-size: 0.95rem;
  white-space: nowrap;
}
.nav {
  display: flex;
  align-items: center;
  gap: var(--space-xl);
  margin-left: auto;
}
.nav a {
  font-weight: 700;
  text-transform: uppercase;
  letter-spacing: 0.07em;
  font-size: 0.72rem;
  color: var(--text-light);
}
.nav a:hover { opacity: 0.5; }
.nav .nav-cta { color: var(--text-color); }
.nav .nav-cta::after { content: ' →'; color: var(--text-light); }

.header-controls { display: flex; align-items: center; gap: var(--space-md); }
.theme-toggle,
.nav-toggle {
  font: inherit;
  font-weight: 700;
  font-size: 0.68rem;
  text-transform: uppercase;
  letter-spacing: 0.07em;
  color: var(--text-light);
  background: transparent;
  border: var(--hairline) solid var(--border-color);
  padding: var(--space-xs) var(--space-sm);
  cursor: pointer;
  transition: var(--transition);
}
.theme-toggle:hover,
.nav-toggle:hover { border-color: var(--gray-50); opacity: 1; }
.nav-toggle { display: none; }

/* --- sections & rhythm ----------------------------------------------------- */
.section { padding-block: var(--space-3xl); }
.section.hero { padding-block: clamp(3.5rem, 10vw, 7rem) var(--space-2xl); }
.prose-block { max-width: var(--measure); }

.prose-block h2,
.section-lead { font-size: clamp(1.5rem, 3vw, 2.1rem); margin-bottom: var(--space-lg); }
.prose-block p { margin-bottom: var(--space-lg); color: var(--gray-90); }
.prose-block p:last-child { margin-bottom: 0; }
.prose-block strong { font-weight: 700; color: var(--text-color); }
.prose-block code {
  font-family: var(--font-mono);
  font-size: 0.9em;
  padding: 0 0.2em;
  border-bottom: var(--hairline) solid var(--border-color);
}

.section-note { color: var(--text-light); margin-top: calc(-1 * var(--space-sm)); }

/* --- hero ------------------------------------------------------------------ */
.hero-copy h1 {
  font-size: clamp(2.2rem, 6vw, 3.8rem);
  line-height: 1.08;
  max-width: 18ch;
  margin-bottom: var(--space-xl);
}
.hero-copy p {
  font-size: clamp(1.05rem, 1.8vw, 1.3rem);
  color: var(--gray-90);
  max-width: 52ch;
  margin: 0;
}
.hero-cta { margin-top: var(--space-2xl); font-size: 0.9rem; }

/* --- outcomes -------------------------------------------------------------- */
.outcomes {
  list-style: none;
  margin: var(--space-2xl) 0 0;
  padding: 0;
  display: grid;
  grid-template-columns: repeat(2, 1fr);
  gap: 1px;
  background: var(--border-color);
  border: var(--hairline) solid var(--border-color);
}
.outcome {
  background: var(--bg-color);
  padding: var(--space-xl);
}
.outcome-label {
  font-size: 1.05rem;
  margin-bottom: var(--space-sm);
}
.outcome-label::before {
  content: '→ ';
  color: var(--text-light);
}
.outcome p { color: var(--text-light); margin: 0; font-size: 0.95rem; }

/* --- stack diagram --------------------------------------------------------- */
.stack {
  margin: var(--space-2xl) 0 0;
  border: var(--rule-frame) solid var(--border-color);
}
.stack-tools {
  display: grid;
  grid-template-columns: repeat(5, 1fr);
  border-bottom: var(--rule-frame) solid var(--border-color);
}
.stack-tool {
  display: flex;
  flex-direction: column;
  gap: var(--space-xxs);
  padding: var(--space-lg) var(--space-md);
  text-align: center;
  border-left: var(--rule-hair) solid var(--border-color);
}
.stack-tool:first-child { border-left: 0; }
.stack-tool-name { font-weight: 700; font-size: 0.9rem; }
.stack-tool-craft { color: var(--text-light); }
.stack-layer {
  padding: var(--space-lg) var(--space-md);
  text-align: center;
}
.stack-platform { border-bottom: var(--rule-hair) solid var(--border-color); }
.stack-layer-title { display: block; margin-bottom: var(--space-xs); color: var(--text-color); }
.stack-layer-sub { color: var(--text-light); font-size: 0.85rem; }

/* --- tools grid ------------------------------------------------------------ */
.tools-grid {
  margin-top: var(--space-2xl);
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(280px, 1fr));
  gap: 1px;
  background: var(--border-color);
  border: var(--hairline) solid var(--border-color);
}
.tool-card {
  background: var(--bg-color);
  padding: var(--space-xl);
  display: flex;
  flex-direction: column;
  gap: var(--space-md);
}
.tool-head {
  display: flex;
  align-items: baseline;
  justify-content: space-between;
  gap: var(--space-md);
}
.tool-name { font-size: 1.25rem; }
.tool-craft { white-space: nowrap; }
.tool-job { color: var(--gray-90); margin: 0; font-size: 0.95rem; }
.tool-foot {
  margin-top: auto;
  padding-top: var(--space-md);
  border-top: var(--hairline) solid var(--border-color);
}
.tool-status {
  display: inline-block;
  font-weight: 700;
  text-transform: uppercase;
  letter-spacing: 0.07em;
  font-size: 0.68rem;
  margin-bottom: var(--space-xs);
}
.tool-note { display: block; color: var(--text-light); font-size: 0.85rem; }

.tool-card--ghost { justify-content: center; }
.tool-ghost { color: var(--text-light); font-size: 0.9rem; font-style: italic; margin: 0; }

/* --- close ----------------------------------------------------------------- */
.section.close { padding-block: var(--space-3xl); }
.section.close h2 { font-size: clamp(1.6rem, 3.5vw, 2.4rem); max-width: 20ch; }

/* --- footer ---------------------------------------------------------------- */
.site-footer {
  border-top: var(--hairline) solid var(--border-color);
  padding-block: var(--space-2xl);
}
.site-footer .inner {
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: var(--space-lg);
  flex-wrap: wrap;
}
.footer-tag { color: var(--text-light); font-size: 0.85rem; font-style: italic; }

/* --- responsive ------------------------------------------------------------ */
@media (max-width: 720px) {
  .nav {
    display: none;
    position: absolute;
    top: 100%;
    left: 0;
    right: 0;
    flex-direction: column;
    align-items: flex-start;
    gap: var(--space-lg);
    background: var(--bg-color);
    border-bottom: var(--hairline) solid var(--border-color);
    padding: var(--space-xl) var(--container-pad);
    margin-left: 0;
  }
  .nav.is-open { display: flex; }
  .nav-toggle { display: inline-block; }
  .outcomes { grid-template-columns: 1fr; }
  .stack-tools { grid-template-columns: repeat(2, 1fr); }
  .stack-tool:nth-child(-n + 2) { border-top: 0; }
  .stack-tool { border-top: var(--rule-hair) solid var(--border-color); }
  .stack-tool:nth-child(odd) { border-left: 0; }
}