/* Landing + contact layout — T019.1 iter 3 (cool SaaS register).
 *
 * Structure: top header bar (wordmark left, nav + actions right) sits
 * full-width on a white surface with a 1px slate rule; body is a
 * centred column at --measure; footer is a quiet single line.
 * Mobile-first; below 768px the inline nav collapses behind a
 * .nav-toggle hamburger that reveals an overlay panel.
 * Depends on theme.css tokens.
 */

body {
  font-family: var(--font-stack-system);
  color: var(--color-fg);
  background: var(--color-bg);
  display: flex;
  flex-direction: column;
  min-height: 100vh;
  -webkit-font-smoothing: antialiased;
  -moz-osx-font-smoothing: grayscale;
  font-feature-settings: "cv02", "cv03", "cv04", "cv11";
}

/* ── Header bar ───────────────────────────────────────────────── */

.site-header {
  position: sticky;
  top: 0;
  z-index: 20;
  width: 100%;
  background: var(--color-header-bg);
  border-bottom: 1px solid var(--color-rule);
  padding: 0 var(--space-3);
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: var(--space-2);
  min-height: var(--header-height);
  box-sizing: border-box;
}

/* ── Sub-nav (breadcrumb) ─────────────────────────────────────────
 * A horizontal extension of the header, shown only on non-home
 * pages. Sticks directly beneath the header so it reads as a second
 * header row. Same markup serves desktop and mobile; on mobile it
 * collapses to a single compact "back to Home" breadcrumb line. */
.site-subnav {
  position: sticky;
  top: var(--header-height);
  z-index: 5;
  width: 100%;
  background: var(--color-header-bg);
  border-bottom: 1px solid var(--color-rule);
  padding: 0 var(--space-3);
  box-sizing: border-box;
}

.breadcrumb {
  list-style: none;
  margin: 0;
  padding: 0.5rem 0;
  display: flex;
  align-items: center;
  gap: 0.375rem;
  min-height: 2.25rem;
  box-sizing: border-box;
}

.breadcrumb__item {
  display: inline-flex;
  align-items: center;
  min-width: 0;
}

.breadcrumb__link {
  display: inline-flex;
  align-items: center;
  gap: 0.375rem;
  font-family: var(--font-stack-geometric);
  font-weight: 600;
  font-size: 0.875rem;
  color: var(--color-accent);
  text-decoration: none;
  padding: 0.25rem 0.5rem;
  margin-left: -0.5rem;
  border-radius: var(--radius);
  -webkit-tap-highlight-color: transparent;
  transition: color 120ms ease, background-color 120ms ease;
}

.breadcrumb__link:hover,
.breadcrumb__link:focus-visible {
  background: var(--color-accent-soft);
  color: var(--color-accent);
}

.breadcrumb__glyph {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  width: 1rem;
  height: 1rem;
  flex: 0 0 auto;
}

.breadcrumb__glyph svg {
  width: 100%;
  height: 100%;
  display: block;
}

.breadcrumb__sep {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  width: 0.875rem;
  height: 0.875rem;
  color: var(--color-muted);
  flex: 0 0 auto;
}

.breadcrumb__sep svg {
  width: 100%;
  height: 100%;
  display: block;
}

.breadcrumb__current {
  font-family: var(--font-stack-geometric);
  font-weight: 500;
  font-size: 0.875rem;
  color: var(--color-muted);
  white-space: nowrap;
  overflow: hidden;
  text-overflow: ellipsis;
}

/* ── Brand lockup: "Federico Carrer."  ⇄  "F.C. Labs" ───────────────
 * The lockup is a CONSTANT-WIDTH overlay: the full-name wordmark stays
 * in normal flow and fixes the width, while the F.C. monogram, the
 * lightsaber bar and the Labs link are absolutely positioned layers
 * that cross-fade in place. Nothing here changes layout on condense,
 * so the rest of the header bar never moves — only the lightsaber
 * (a transform-only animation) travels. */
.brand-lockup {
  position: relative;
  display: inline-flex;
  align-items: center;
  min-width: 0;
}

.brand {
  position: relative;
  display: inline-flex;
  align-items: center;
  padding: 0.25rem 0.4rem;
  margin: 0 -0.4rem;
  border-radius: var(--radius);
  text-decoration: none;
  color: var(--color-fg);
  transition: background-color 120ms ease;
}

.brand:hover,
.brand:focus-visible {
  background: var(--color-accent-soft);
}

/* Full-name wordmark — the only IN-FLOW layer, so it fixes the lockup
 * width. Its left padding reserves room for the masthead bar. Fades
 * out (opacity only, no width change) when condensed; it keeps its
 * box so the lockup width — and the whole header — stays put. */
.wordmark {
  display: inline-flex;
  align-items: baseline;
  padding-left: 0.75rem;
  font-family: var(--font-stack-geometric);
  font-weight: 700;
  font-size: 1.0625rem;
  letter-spacing: 0.005em;
  color: var(--color-fg);
  white-space: nowrap;
  opacity: 1;
  transition: opacity 200ms ease;
}

.wordmark::after {
  content: ".";
  margin-left: 0.06em;
  color: var(--color-accent);
  font-weight: 800;
}

/* F.C. monogram — same logotype as the wordmark, overlaid at the left.
 * Hidden (opacity) when expanded, fades in place when condensed. The
 * padding + compensating offset give the hover chip breathing room
 * without moving the visible glyphs. */
.brand-mark {
  position: absolute;
  left: 0;
  top: 50%;
  transform: translateY(-50%);
  display: inline-flex;
  align-items: baseline;
  padding: 0.25rem 0.4rem;
  border-radius: var(--radius);
  font-family: var(--font-stack-geometric);
  font-weight: 700;
  font-size: 1.0625rem;
  line-height: 1;
  letter-spacing: 0.005em;
  color: var(--color-fg);
  white-space: nowrap;
  opacity: 0;
  transition: opacity 220ms ease, background-color 120ms ease;
}

/* Accent dots that echo the wordmark's trailing dot in the F.C.
 * monogram (one between the initials, one trailing). */
.brand-dot {
  color: var(--color-accent);
  font-weight: 800;
}

/* Lightsaber bar — the ONLY thing that moves. Absolutely positioned
 * and centred via auto margins (not transform) so the JS sweep owns
 * transform entirely. */
.brand-bar {
  position: absolute;
  left: 0.4rem;
  top: 0;
  bottom: 0;
  width: 0.25rem;
  height: 0.85rem;
  margin: auto 0;
  border-radius: 999px;
  background: var(--color-accent);
  opacity: 1;
  transform-origin: center center;
}

/* Labs link — overlaid to the right of the monogram. Hidden (opacity)
 * when expanded, fades in place when condensed. No motion. */
.brand-labs {
  position: absolute;
  left: 1.95rem;
  top: 50%;
  transform: translateY(-50%);
  z-index: 1;
  display: inline-flex;
  align-items: center;
  padding: 0.3rem 0.5rem;
  border-radius: var(--radius);
  text-decoration: none;
  opacity: 0;
  visibility: hidden;
  -webkit-tap-highlight-color: transparent;
  transition: opacity 220ms ease, background-color 120ms ease,
    visibility 0s linear 220ms;
}

.brand-labs:hover,
.brand-labs:focus-visible {
  background: var(--color-accent-soft);
}

.brand-labs__text {
  font-family: "Permanent Marker", var(--font-stack-system);
  font-weight: 400;
  font-size: 1.125rem;
  line-height: 1;
  color: var(--color-accent);
  white-space: nowrap;
  transform: rotate(-3deg);
}

/* Condensed state: cross-fade the full name into "F.C. Labs" — all
 * opacity, no layout change. Reveals are delayed to land in step with
 * the ~700ms JS bar-sweep: the name fades as the bar passes, F.C.
 * forms in its wake, and "Labs" fades in as the bar powers off. */
.site-header[data-condensed="true"] .brand-mark {
  opacity: 1;
  transition: opacity 220ms ease 280ms;
}

/* The bar is a transition flourish only: it powers off (fades out)
 * where the trailing dot sat, leaving "F.C. Labs" with no resting
 * separator. The JS drives the visible fade; this is the rest value. */
.site-header[data-condensed="true"] .brand-bar {
  opacity: 0;
}

.site-header[data-condensed="true"] .wordmark {
  opacity: 0;
  transition: opacity 200ms ease 120ms;
}

.site-header[data-condensed="true"] .brand-labs {
  opacity: 1;
  visibility: visible;
  transition: opacity 260ms ease 500ms, background-color 120ms ease,
    visibility 0s;
}

/* Condensed Home affordance: shrink the interactive/hover area of the
 * Home link to just the F.C. monogram. The wide invisible wordmark no
 * longer captures the pointer (no giant hover rectangle), and hovering
 * the Labs chip can't also light up the Home link (no nested boxes).
 * pointer-events:auto on the monogram still activates the parent
 * anchor on click. */
.site-header[data-condensed="true"] .brand {
  pointer-events: none;
}

.site-header[data-condensed="true"] .brand-mark {
  pointer-events: auto;
  cursor: pointer;
}

.site-header[data-condensed="true"] .brand:hover,
.site-header[data-condensed="true"] .brand:focus-visible {
  background: transparent;
}

.site-header[data-condensed="true"] .brand-mark:hover,
.site-header[data-condensed="true"] .brand:focus-visible .brand-mark {
  background: var(--color-accent-soft);
}

/* The nav "Labs" item fades out but KEEPS its box (visibility, not
 * display) so the rest of the nav doesn't shift. */
.site-header[data-condensed="true"] .nav-item-labs {
  visibility: hidden;
  opacity: 0;
}

.nav-item-labs {
  transition: opacity 200ms ease;
}

@media (prefers-reduced-motion: reduce) {
  .brand-mark,
  .brand-bar,
  .wordmark,
  .brand-labs {
    transition: none;
  }
}

/* Primary nav */
.site-nav {
  display: flex;
  align-items: center;
  gap: var(--space-3);
  flex-wrap: wrap;
}

.nav-list {
  list-style: none;
  margin: 0;
  padding: 0;
  display: flex;
  gap: var(--space-3);
}

.nav-link {
  font-family: var(--font-stack-geometric);
  font-weight: 500;
  font-size: 0.9375rem;
  color: var(--color-muted);
  text-decoration: none;
  padding: 0.4rem 0.625rem;
  border-radius: var(--radius);
  transition: color 120ms ease, background-color 120ms ease;
}

.nav-link:hover,
.nav-link:focus-visible {
  color: var(--color-fg);
  background: var(--color-accent-soft);
}

/* The "Labs" nav item wears the same whiteboard-marker brand as the
 * condensed logo's Labs, so it reads as the same sub-brand whether it
 * lives in the nav (expanded) or the logo lockup (condensed). */
.nav-item-labs .nav-link {
  font-family: "Permanent Marker", var(--font-stack-system);
  font-weight: 400;
  font-size: 1.0625rem;
  letter-spacing: 0.01em;
  color: var(--color-accent);
  transform: rotate(-3deg);
}

.nav-item-labs .nav-link:hover,
.nav-item-labs .nav-link:focus-visible {
  color: var(--color-accent);
  background: var(--color-accent-soft);
}

.nav-divider {
  display: inline-block;
  width: 1px;
  height: 1.25rem;
  background: var(--color-rule);
  align-self: center;
}

@media (max-width: 480px) {
  .nav-divider {
    display: none;
  }
}

.nav-actions {
  display: flex;
  align-items: center;
  gap: var(--space-2);
}

/* Plain-text-link buttons (locale switcher) */
.link-button {
  appearance: none;
  background: transparent;
  border: 0;
  padding: 0.4rem 0.625rem;
  margin: 0;
  font: inherit;
  font-size: 0.875rem;
  color: var(--color-muted);
  border-radius: var(--radius);
  cursor: pointer;
  transition: color 120ms ease, background-color 120ms ease;
}

.link-button:hover,
.link-button:focus-visible {
  color: var(--color-fg);
  background: var(--color-accent-soft);
  text-decoration: none;
}

/* ── Appearance settings cluster ──────────────────────────────── */

.appearance-settings {
  display: inline-flex;
  align-items: center;
  gap: 0.125rem;
  padding: 0.1875rem;
  background: var(--color-bg);
  border: 1px solid var(--color-rule);
  border-radius: 999px;
}

.appearance-settings__label {
  position: absolute;
  width: 1px;
  height: 1px;
  padding: 0;
  margin: -1px;
  overflow: hidden;
  clip: rect(0, 0, 0, 0);
  white-space: nowrap;
  border: 0;
}

.icon-button {
  appearance: none;
  display: inline-flex;
  align-items: center;
  justify-content: center;
  gap: 0.25rem;
  min-width: 1.875rem;
  height: 1.875rem;
  padding: 0 0.5rem;
  background: transparent;
  border: 0;
  border-radius: 999px;
  font: inherit;
  font-size: 0.8125rem;
  font-weight: 500;
  color: var(--color-muted);
  text-decoration: none;
  cursor: pointer;
  transition: color 120ms ease, background-color 120ms ease;
}

a.icon-button {
  -webkit-tap-highlight-color: transparent;
}

.icon-button:hover,
.icon-button:focus-visible {
  color: var(--color-fg);
  background: var(--color-surface);
}

.icon-button[aria-pressed="true"] {
  color: var(--color-fg);
  background: var(--color-surface);
  box-shadow: var(--shadow-sm);
}

.icon-button__glyph {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  width: 1rem;
  height: 1rem;
  flex: 0 0 auto;
}

.icon-button__glyph svg {
  width: 100%;
  height: 100%;
  display: block;
}

/* The theme toggle's two glyphs swap based on which mode is active.
 * Default (light): moon visible (click to go dark).
 * Dark via OS preference or explicit data-theme="dark": sun visible. */
.theme-toggle__moon {
  display: inline-flex;
}

.theme-toggle__sun {
  display: none;
}

:root[data-theme="dark"] .theme-toggle__moon {
  display: none;
}

:root[data-theme="dark"] .theme-toggle__sun {
  display: inline-flex;
}

@media (prefers-color-scheme: dark) {
  :root:not([data-theme="light"]) .theme-toggle__moon {
    display: none;
  }

  :root:not([data-theme="light"]) .theme-toggle__sun {
    display: inline-flex;
  }
}

/* Primary CTA — used in header (small) and elsewhere */
.primary-cta {
  display: inline-flex;
  align-items: center;
  gap: 0.375rem;
  padding: 0.5rem 1rem;
  font: inherit;
  font-weight: 600;
  font-size: 0.875rem;
  color: var(--color-accent-fg);
  background: var(--color-accent);
  border: 1px solid var(--color-accent);
  border-radius: var(--radius);
  box-shadow: var(--shadow-sm);
  cursor: pointer;
  text-decoration: none;
  transition: filter 120ms ease, transform 120ms ease;
}

.primary-cta:hover,
.primary-cta:focus-visible {
  filter: brightness(1.06);
  color: var(--color-accent-fg);
}

.primary-cta:active {
  transform: translateY(1px);
}

.primary-cta--sm {
  padding: 0.375rem 0.75rem;
  font-size: 0.8125rem;
}

/* Header actions cluster — persistent Sign-in + (mobile) toggle. */
.header-actions {
  display: inline-flex;
  align-items: center;
  gap: var(--space-2);
  order: 3;
}

.site-nav {
  order: 2;
}

/* Hamburger toggle — visible on mobile only */
.nav-toggle {
  display: none;
  appearance: none;
  width: 2.25rem;
  height: 2.25rem;
  align-items: center;
  justify-content: center;
  background: transparent;
  border: 1px solid var(--color-rule);
  border-radius: var(--radius);
  color: var(--color-fg);
  cursor: pointer;
  padding: 0;
  transition: background-color 120ms ease, border-color 120ms ease;
}

.nav-toggle:hover,
.nav-toggle:focus-visible {
  background: var(--color-accent-soft);
  border-color: var(--color-rule-strong);
}

.nav-toggle__bars {
  display: block;
  position: relative;
  width: 1rem;
  height: 0.75rem;
}

.nav-toggle__bars::before,
.nav-toggle__bars::after,
.nav-toggle__bars > span {
  content: "";
  position: absolute;
  left: 0;
  width: 100%;
  height: 1.5px;
  background: currentColor;
  border-radius: 1px;
  transition: transform 160ms ease, opacity 160ms ease, top 160ms ease;
}

.nav-toggle__bars::before { top: 0; }
.nav-toggle__bars > span { top: calc(50% - 0.75px); }
.nav-toggle__bars::after { top: calc(100% - 1.5px); }

.nav-toggle[aria-expanded="true"] .nav-toggle__bars::before {
  top: calc(50% - 0.75px);
  transform: rotate(45deg);
}

.nav-toggle[aria-expanded="true"] .nav-toggle__bars > span {
  opacity: 0;
}

.nav-toggle[aria-expanded="true"] .nav-toggle__bars::after {
  top: calc(50% - 0.75px);
  transform: rotate(-45deg);
}

.nav-backdrop {
  display: none;
}

/* ── Body ─────────────────────────────────────────────────────── */

main#content {
  flex: 1 0 auto;
  width: 100%;
  max-width: var(--measure);
  margin: 0 auto;
  padding: var(--space-section) var(--space-3);
  display: flex;
  flex-direction: column;
  gap: var(--space-section);
  box-sizing: border-box;
}

/* Headings */
h1,
h2,
h3 {
  font-family: var(--font-stack-system);
  font-weight: 700;
  letter-spacing: -0.018em;
  line-height: 1.2;
}

/* Tagline (hero-ish, but quiet) */
.tagline {
  margin: 0;
}

.tagline h1 {
  margin: 0 0 var(--space-2) 0;
  font-size: 1.875rem;
  color: var(--color-fg);
}

.tagline-helper {
  margin: 0;
  font-size: 1rem;
  color: var(--color-muted);
  max-width: 30rem;
}

/* Contact block (F020 slot) */
.contact {
  border-top: 1px solid var(--color-rule);
  padding-top: var(--space-section);
  margin: 0;
  scroll-margin-top: calc(var(--header-height) + var(--space-2));
}

.contact h2 {
  margin: 0 0 var(--space-1) 0;
  font-size: 1.25rem;
  color: var(--color-fg);
}

.contact-helper {
  margin: 0 0 var(--space-3) 0;
  color: var(--color-muted);
  max-width: 32rem;
}

/* Teaser CTA on the landing page (links to /<locale>/contact/) */

.contact-cta-row {
  margin: 0;
}

.contact-cta {
  display: inline-flex;
  align-items: center;
  gap: 0.25rem;
  font-family: var(--font-stack-system);
  font-weight: 600;
  font-size: 0.9375rem;
  color: var(--color-accent);
  text-decoration: none;
  padding: 0.375rem 0;
  border-bottom: 1px solid transparent;
  transition: gap 120ms ease, border-color 120ms ease;
}

.contact-cta:hover,
.contact-cta:focus-visible {
  gap: 0.5rem;
  border-bottom-color: var(--color-accent);
}

/* ── /<locale>/contact/ page ──────────────────────────────────── */

main#content.contact-page {
  max-width: var(--container);
  gap: var(--space-section);
}

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

.contact-intro h1 {
  margin: 0 0 var(--space-2) 0;
  font-size: 1.875rem;
  color: var(--color-fg);
}

.contact-intro p {
  margin: 0;
  font-size: 1rem;
  color: var(--color-muted);
  max-width: 32rem;
}

.contact-form {
  margin: 0;
  padding: 0;
  background: var(--color-surface);
  border: 1px solid var(--color-rule);
  border-radius: var(--radius);
  overflow: hidden;
  box-shadow: var(--shadow-sm);
}

.contact-form-iframe {
  display: block;
  width: 100%;
  min-height: 42rem;
  border: 0;
  background: transparent;
  color-scheme: light;
}

@media (max-width: 767px) {
  main#content.contact-page {
    padding-left: 0;
    padding-right: 0;
  }

  .contact-intro {
    padding-left: var(--space-3);
    padding-right: var(--space-3);
  }

  .contact-form {
    border-left: 0;
    border-right: 0;
    border-radius: 0;
    box-shadow: none;
  }
}

@media (min-width: 768px) {
  .contact-intro h1 {
    font-size: 2.25rem;
  }

  .contact-form-iframe {
    min-height: 52rem;
  }
}

/* ── /<locale>/login/ page (mock — F007 placeholder) ──────────── */

main#content.login-page {
  align-items: center;
  justify-content: flex-start;
}

.login-card {
  width: 100%;
  max-width: 26rem;
  margin: 0 auto;
  padding: var(--space-4);
  display: flex;
  flex-direction: column;
  gap: var(--space-2);
  background: var(--color-surface);
  border: 1px solid var(--color-rule);
  border-radius: var(--radius);
  box-shadow: var(--shadow-md);
  box-sizing: border-box;
}

.login-card h1 {
  margin: 0;
  font-size: 1.5rem;
  color: var(--color-fg);
}

.login-intro {
  margin: 0;
  font-size: 0.9375rem;
  line-height: 1.5;
  color: var(--color-muted);
}

.login-form {
  display: flex;
  flex-direction: column;
  gap: var(--space-2);
  margin: var(--space-1) 0 0 0;
}

.login-field {
  display: flex;
  flex-direction: column;
  gap: 0.375rem;
}

.login-field__label {
  font-size: 0.8125rem;
  font-weight: 600;
  color: var(--color-fg);
}

.login-field__input {
  width: 100%;
  box-sizing: border-box;
  padding: 0.625rem 0.75rem;
  font: inherit;
  font-size: 0.9375rem;
  color: var(--color-fg);
  background: var(--color-bg);
  border: 1px solid var(--color-rule-strong);
  border-radius: var(--radius);
  transition: border-color 120ms ease, box-shadow 120ms ease;
}

.login-field__input::placeholder {
  color: var(--color-muted);
}

.login-field__input:focus-visible {
  outline: none;
  border-color: var(--color-accent);
  box-shadow: 0 0 0 3px var(--color-accent-soft);
}

.login-field__input[aria-invalid="true"] {
  border-color: var(--color-danger);
}

.login-error {
  margin: 0;
  padding: 0.5rem 0.75rem;
  font-size: 0.8125rem;
  line-height: 1.4;
  color: var(--color-danger);
  background: var(--color-danger-soft);
  border: 1px solid var(--color-danger);
  border-radius: var(--radius);
}

.login-error[hidden] {
  display: none;
}

.login-submit {
  justify-content: center;
  width: 100%;
  padding: 0.625rem 1rem;
  font-size: 0.9375rem;
}

.login-back {
  align-self: flex-start;
  margin-top: var(--space-1);
  font-size: 0.8125rem;
  font-weight: 600;
  color: var(--color-accent);
  text-decoration: none;
}

.login-back:hover,
.login-back:focus-visible {
  text-decoration: underline;
}

@media (min-width: 768px) {
  main#content.login-page {
    justify-content: center;
  }

  .login-card {
    padding: calc(var(--space-4) + 0.5rem);
  }
}

/* ── Footer ───────────────────────────────────────────────────── */

.site-footer {
  width: 100%;
  border-top: 1px solid var(--color-rule);
  padding: var(--space-2) var(--space-3);
  display: flex;
  align-items: baseline;
  justify-content: center;
  gap: var(--space-2);
  color: var(--color-muted);
  font-size: 0.875rem;
  box-sizing: border-box;
}

.site-footer p {
  margin: 0;
}

/* ── Breakpoints ──────────────────────────────────────────────── */

@media (max-width: 767px) {
  /* Mobile is always condensed ("F.C. Labs"). These mirror the
   * data-condensed rules so the layout is correct even before the
   * scroll controller runs / if JS is unavailable. */
  .brand-mark {
    opacity: 1;
  }

  .brand-bar {
    opacity: 0;
  }

  .wordmark {
    opacity: 0;
  }

  .brand-labs {
    opacity: 1;
    visibility: visible;
  }

  /* Mirror the condensed Home affordance for the JS-free / always-on
   * mobile case: Home interaction limited to the monogram. */
  .brand {
    pointer-events: none;
  }

  .brand-mark {
    pointer-events: auto;
    cursor: pointer;
  }

  .brand:hover,
  .brand:focus-visible {
    background: transparent;
  }

  .brand-mark:hover,
  .brand:focus-visible .brand-mark {
    background: var(--color-accent-soft);
  }

  /* In the vertical drawer the Labs item is fully removed (no reserved
   * gap) — overrides the desktop "visibility: hidden" reserve rule. */
  .nav-item-labs,
  .site-header[data-condensed="true"] .nav-item-labs {
    display: none;
  }

  .nav-toggle {
    display: inline-flex;
  }

  .site-nav {
    position: fixed;
    top: var(--header-height);
    right: 0;
    bottom: 0;
    width: min(20rem, 80vw);
    flex-direction: column;
    align-items: stretch;
    gap: var(--space-1);
    padding: var(--space-3);
    background: var(--color-surface);
    border-left: 1px solid var(--color-rule);
    box-shadow: var(--shadow-md);
    transform: translateX(100%);
    transition: transform 200ms ease;
    overflow-y: auto;
  }

  .site-nav[data-open="true"] {
    transform: translateX(0);
  }

  .nav-list {
    flex-direction: column;
    align-items: stretch;
    gap: var(--space-1);
  }

  .nav-link {
    font-size: 1rem;
    padding: 0.625rem 0.75rem;
  }

  .nav-divider {
    width: 100%;
    height: 1px;
    margin: var(--space-1) 0;
  }

  .nav-actions {
    flex-direction: column;
    align-items: stretch;
    gap: var(--space-1);
  }

  .link-button {
    text-align: left;
    padding: 0.625rem 0.75rem;
    font-size: 1rem;
  }

  .primary-cta--sm {
    justify-content: center;
    padding: 0.625rem 0.75rem;
    font-size: 0.9375rem;
  }

  .nav-backdrop {
    display: none;
    position: fixed;
    top: var(--header-height);
    left: 0;
    right: 0;
    bottom: 0;
    background: rgba(15, 23, 42, 0.4);
    z-index: 10;
  }

  .nav-backdrop[data-open="true"] {
    display: block;
  }
}

@media (min-width: 768px) {
  .site-header {
    padding: 0 var(--space-4);
  }

  .site-subnav {
    padding: 0 var(--space-4);
  }

  .wordmark,
  .brand-mark {
    font-size: 1.125rem;
  }

  /* F.C. is a touch wider at the desktop size, so nudge Labs right. */
  .brand-labs {
    left: 2.05rem;
  }

  .nav-link {
    font-size: 0.9375rem;
  }

  main#content {
    padding: 4rem var(--space-4);
    gap: 4rem;
  }

  .tagline h1 {
    font-size: 2.25rem;
  }

  .tagline-helper {
    font-size: 1.0625rem;
  }

  .contact h2 {
    font-size: 1.375rem;
  }

  .site-footer {
    padding: var(--space-2) var(--space-4);
  }
}