/* Neutral surfaces/type sampled from antigravity.google; accent fills sampled
   from the supplied official Antigravity icon. Presentation choices, not a full brand book.
   Celestial light comes from Astrum's original procedural spectral functions. */
@font-face{font-family:'Google Sans Flex';font-style:normal;font-weight:400;font-display:swap;src:url('vendor/google-sans-flex/regular.ttf') format('truetype')}
html{--font-sans:'Google Sans Flex','Helvetica Neue',Arial,sans-serif;--ag-blue:#3186ff;--ag-red:#fc413d;--ag-green:#00b95c;--ag-yellow:#ffe432;--ag-amber:#fbbc04;--ag-blue-light:#749bff;--ag-yellow-light:#ffee48}

/* Auto follows the system by default. The deck theme control can choose light or dark.
   Explicit data-theme overrides the media fallback. Drawings use theme tokens. */
html{--bg:#fff;--fg:#121317;--muted:#45474d;--panel:#f8f9fc;--line:rgba(33,34,38,.12);--veil:rgba(255,255,255,.91);--viz-a:var(--ag-blue);--viz-b:var(--ag-red);color-scheme:light}
@media (prefers-color-scheme:dark){
  html:not([data-theme=light]){--bg:#000;--fg:#f5f5f5;--muted:#c1c5ce;--panel:#1e1e1e;--line:#45474d;--veil:rgba(0,0,0,.86);--viz-a:var(--ag-blue-light);--viz-b:var(--ag-yellow-light);color-scheme:dark}
}
html[data-theme=dark]{--bg:#000;--fg:#f5f5f5;--muted:#c1c5ce;--panel:#1e1e1e;--line:#45474d;--veil:rgba(0,0,0,.86);--viz-a:var(--ag-blue-light);--viz-b:var(--ag-yellow-light);color-scheme:dark}

body,button,select{font-family:var(--font-sans)}
.question-cue,.cover-subtitle,.cover-meta,.attribution,#notes,#notes h3,.diagram-label,.diagram-note{font-family:var(--font-sans)}
#celestial-field{position:fixed;inset:0;width:100%;height:100%;z-index:-3;pointer-events:none;opacity:0;transition:opacity 1.2s ease}
/* Sky slides lighten the same scrim instead of swapping its gradient, so the change
   cross-fades with the scrim's opacity transition rather than snapping. Desktop only:
   the phone column keeps its solid reading veil. */
@media(min-width:901px) and (min-aspect-ratio:1/1){html[data-celestial=true] .art-wash{opacity:.5}}
@media(prefers-reduced-motion:reduce){#celestial-field{transition:none}}

.answer,.viz text{font-family:var(--font-sans)}
/* Answer headlines on question slides share the answer's face, not a system Helvetica. */
.topic-opening h1{font-family:var(--font-sans);letter-spacing:-.01em}
/* Preserve the requested background zoom in the unsupported-Canvas still fallback. */
#svg-source.static-art{overflow:hidden}#svg-source.static-art svg{transform:scale(2);transform-origin:center}