body { margin: 0; }
.site-header { position: relative; z-index: 1; background: #f4f0eb; border-bottom: 1px solid rgba(28,18,8,.15); }
.site-header nav { display: flex; flex-wrap: wrap; gap: .5rem 1.5rem; max-width: 1200px; margin: auto; padding: 1rem clamp(1rem,4vw,3rem); }
.site-header a { padding: .5rem 0; color: #1c1208; font: 500 .85rem/1.5 'IBM Plex Mono', monospace; text-decoration: none; }
.site-header a:hover, .site-header a[aria-current] { color: #1e3a8a; text-decoration: underline; text-underline-offset: .35em; }
a:focus-visible, iframe:focus-visible { outline: 3px solid #2563eb; outline-offset: 4px; }
.layout { min-height: min(650px, 85vh); }
#quiz { background: #123a63; }
.quiz-frame { display: block; border: 0; width: 100%; height: 100vh; min-height: 780px; }
.offer-page { background: #f4f0eb; color: #1c1208; font-family: 'Newsreader', Georgia, serif; min-height: 100vh; }
.offer-content { max-width: 760px; padding: clamp(3rem,8vw,7rem) 1.5rem; margin: auto; }
.offer-content h1 { font-size: clamp(2.5rem,7vw,4.5rem); font-weight: 300; line-height: 1.1; }
.offer-content p { font-size: 1.2rem; line-height: 1.75; margin-top: 1.5rem; }
.offer-content .offer-meta { font: .85rem/1.6 'IBM Plex Mono', monospace; color: #5a4433; }
@media (max-width: 600px) { .site-header nav { gap: .25rem 1rem; } .site-header a { font-size: .75rem; } .quiz-frame { min-height: 900px; } }

.quiz-home { background:#123a63; }
.quiz-home .site-header { background:#123a63; border-bottom-color:rgba(143,211,236,.2); }
.quiz-home .site-header a { color:#e8f4ff; }
.quiz-home .site-header a:hover, .quiz-home .site-header a[aria-current] { color:#8fd3ec; }

/* Shared river palette; the operating system controls light/dark mode. */
:root {
  color-scheme: light dark;
  --page-bg: #eef6fa;
  --page-text: #123047;
  --page-muted: #466477;
  --page-border: #799aac;
  --page-accent: #175779;
  --page-input: #ffffff;
  --page-button: #123a63;
  --page-button-text: #e8f4ff;
}
:root[data-theme="dark"] {
    --page-bg: #071d30;
    --page-text: #e8f4ff;
    --page-muted: #b7d5e4;
    --page-border: #618ba1;
    --page-accent: #8fd3ec;
    --page-input: #102b40;
    --page-button: #d9f3fa;
    --page-button-text: #123a63;
}
body.quiz-home, body.offer-page, #quiz { background: var(--page-bg); color: var(--page-text); }
.site-header, .quiz-home .site-header { background: var(--page-bg); border-bottom-color: var(--page-border); }
.site-header a, .quiz-home .site-header a { color: var(--page-text); }
.site-header a:hover, .site-header a[aria-current], .quiz-home .site-header a:hover, .quiz-home .site-header a[aria-current] { color: var(--page-accent); }
.offer-content h1, .offer-content p { color: var(--page-text); }
.offer-content .offer-meta, .offer-content .small-note { color: var(--page-muted); }
.offer-content .input-row { background: var(--page-input); border-color: var(--page-border); }
.offer-content input[type=email] { color: var(--page-text); }
.offer-content input::placeholder { color: var(--page-muted); }
.offer-content button { background: var(--page-button); color: var(--page-button-text); }
.offer-content button:hover { background: var(--page-accent); color: var(--page-bg); }
.offer-content .input-row:focus-within { border-color: var(--page-accent); box-shadow: 0 0 0 3px color-mix(in srgb, var(--page-accent) 25%, transparent); }
a:focus-visible, button:focus-visible, input:focus-visible, iframe:focus-visible { outline: 3px solid var(--page-accent); outline-offset: 3px; }

.theme-toggle { margin-left:auto; padding:.2rem .6rem; border:1px solid var(--page-border); border-radius:50%; background:transparent; color:var(--page-text); font:1.5rem/1.2 Georgia,serif; cursor:pointer; }
.theme-toggle:hover { background:var(--page-input); }

/* Anchor the appearance control to the header edge, not the nav column. */
.site-header nav { padding-right: 5rem; }
.theme-toggle { position: absolute; top: .75rem; right: 1rem; margin-left: 0; }

.site-header nav { max-width: none; margin: 0; }

.theme-toggle { width: 2.5rem; height: 2.5rem; padding: 0; display: grid; place-items: center; line-height: 1; border-radius: 50%; }

.coming-soon-banner {
  display: inline-block;
  margin: 0 0 2.5rem;
  padding: .7rem 1.5rem;
  background: var(--page-button);
  color: var(--page-button-text);
  font: 500 .85rem/1.5 'IBM Plex Mono', monospace;
  letter-spacing: .12em;
  text-transform: uppercase;
  transform: rotate(-5deg);
}

@media (max-width:400px) {
  .site-header nav { padding: .65rem 4.25rem .65rem 1rem; gap:.25rem .75rem; }
  .site-header a { font-size:.7rem; }
  .theme-toggle { top:.65rem; right:.75rem; }
  .quiz-frame { min-height:640px; height:calc(100svh - 110px); }
}