:root {
  color-scheme: light;
}

.header-actions {
  display: flex;
  align-items: center;
  gap: clamp(18px, 3vw, 36px);
}

.theme-toggle {
  appearance: none;
  display: inline-flex;
  align-items: center;
  gap: 8px;
  min-height: 42px;
  padding: 7px 12px;
  border: 1px solid var(--line);
  background: transparent;
  color: var(--ink);
  font: 700 .78rem/1 var(--sans);
  letter-spacing: .06em;
  text-transform: uppercase;
  cursor: pointer;
  transition: background .2s, color .2s, transform .2s;
}

.theme-toggle:hover {
  background: var(--yellow);
  color: #102a43;
  transform: rotate(-2deg);
}

.theme-toggle:focus-visible {
  outline: 3px solid var(--coral);
  outline-offset: 3px;
}

.theme-icon {
  font-size: 1.18rem;
}

html[data-theme="dark"] {
  color-scheme: dark;
  --ink: #e6eef1;
  --paper: #071820;
  --cream: #f7f2e8;
  --yellow: #f6c453;
  --coral: #ff8468;
  --blue: #57a5c4;
  --green: #55a783;
  --line: rgba(230, 238, 241, .2);
}

html[data-theme="dark"] body {
  background-image: linear-gradient(rgba(230, 238, 241, .045) 1px, transparent 1px);
}

html[data-theme="dark"] .topbar {
  background: rgba(7, 24, 32, .93);
}

html[data-theme="dark"] .brand-mark,
html[data-theme="dark"] .ticker,
html[data-theme="dark"] .motto {
  color: #102a43;
}

html[data-theme="dark"] .brand-mark {
  box-shadow: 3px 3px 0 #7fa1af;
}

html[data-theme="dark"] .button {
  background: var(--yellow);
  color: #102a43;
  box-shadow: 6px 6px 0 #315463;
}

html[data-theme="dark"] .button:hover {
  box-shadow: 3px 3px 0 #315463;
}

html[data-theme="dark"] .hero-art {
  background: #102b36;
  box-shadow: 18px 22px 0 rgba(0, 0, 0, .28);
}

html[data-theme="dark"] .stamp {
  background: #0b212a;
}

html[data-theme="dark"] .quests,
html[data-theme="dark"] footer {
  background: #030e13;
  color: #f7f2e8;
}

html[data-theme="dark"] .quest-math { background: #17485b; }
html[data-theme="dark"] .quest-books { background: #753a30; }
html[data-theme="dark"] .quest-world { background: #265540; }
html[data-theme="dark"] .quest-spanish { background: #624e25; }
html[data-theme="dark"] .book.navy { background: #153744; }
html[data-theme="dark"] .motto .section-number { color: #102a43; }
html[data-theme="dark"] .motto-rule span { background: #102a43; }
html[data-theme="dark"] .motto-rule b { border-color: #102a43; }

@media (max-width: 850px) {
  .header-actions { gap: 0; }
}

@media (max-width: 430px) {
  .theme-label { display: none; }
  .theme-toggle { width: 42px; justify-content: center; padding: 7px; }
}