:root {
  /* Brand palette */
  --color-navy-950: #061522;
  --color-navy-900: #0a2035;
  --color-navy-700: #173b5b;
  --color-gold-500: #c5a45e;
  --color-gold-300: #dec98f;
  --color-ivory-100: #f7f2e8;
  --color-ivory-200: #eee5d6;
  --color-ink: #10283e;
  --color-muted: #718092;

  /*
   * Editorial tabletop palette, retuned against the Final Visual Reference.
   * The reference is a lit photograph: a bright warm highlight behind the
   * copy (#FDF6E8) falling to a mid-tone where the cards rest (#E0D2C8) and
   * a deeper plinth shade (#B4A6A0). The base stays below the ivory Question
   * Face so a revealed card keeps its separation from the table.
   */
  --color-table-base: #E6DACA;
  --color-table-light: #FCF5E9;
  --color-table-warm-mid: #E0D2C8;
  --color-table-shadow: #C0B0A2;
  --color-table-cool-accent: #C6C2B8;
  --color-table-mid: var(--color-table-warm-mid);
  --color-table-highlight: var(--color-table-light);
  --tabletop-texture-opacity: 0.012;
  --tabletop-editorial-shadow-opacity: 0.035;

  /* Shared editorial environment */
  --editorial-environment-light-opacity: 0.42;
  --editorial-environment-ambient-opacity: 0.24;
  --editorial-environment-botanical-opacity: 0.08;
  --editorial-environment-arc-opacity: 0.3;
  --editorial-environment-reflection-opacity: 0.14;
  --editorial-environment-asset-opacity: 1;
  --editorial-environment-portrait-position: 50% 50%;
  --editorial-environment-landscape-position: 50% 46%;

  /* Semantic color roles */
  --color-page: var(--color-table-base);
  --color-surface-dark: var(--color-navy-900);
  --color-text-on-dark: var(--color-ivory-100);
  --color-border-dark: var(--color-navy-700);
  --color-accent: var(--color-gold-500);
  --color-card-back: var(--color-navy-900);
  --color-card-back-deep: var(--color-navy-950);
  --color-question-face: var(--color-ivory-100);
  --color-card-edge: var(--color-ivory-200);

  /* Typography */
  --font-serif:
    "Noto Serif TC", "Songti TC", "PMingLiU", serif;
  --font-sans:
    "Inter", "Noto Sans TC", system-ui, -apple-system, BlinkMacSystemFont,
    "Segoe UI", sans-serif;
  --font-size-sm: 0.875rem;
  --font-size-base: 1rem;
  --line-height-tight: 1.25;
  --line-height-body: 1.6;
  --font-weight-regular: 400;
  --font-weight-medium: 500;

  /* Spacing */
  --space-1: 0.25rem;
  --space-2: 0.5rem;
  --space-3: 0.75rem;
  --space-4: 1rem;
  --space-5: 1.25rem;
  --space-6: 1.5rem;
  --space-8: 2rem;
  --space-10: 2.5rem;
  --space-12: 3rem;
  --space-16: 4rem;

  /* Shared dimensions */
  --content-max-width: 960px;
  --screen-gutter: 20px;
  --screen-safe-bottom: 24px;
  --touch-target: 44px;
  --card-width: min(76vw, 330px);
  --card-aspect-ratio: 3 / 4;

  /* Shape and elevation */
  --radius-sm: 8px;
  --radius-md: 12px;
  --card-radius: 18px;
  --shadow-surface: 0 12px 32px rgb(0 0 0 / 20%);
  --shadow-card:
    0 24px 64px rgb(0 0 0 / 34%),
    0 8px 20px rgb(0 0 0 / 24%);

  /* Focus */
  --focus-ring-width: 2px;
  --focus-ring-color: var(--color-navy-900);
  --focus-ring-offset: 3px;
  --focus-ring-offset-color: var(--color-table-light);

  /* Motion */
  --duration-fast: 150ms;
  --duration-base: 250ms;
  --duration-slow: 450ms;
  --ease-standard: cubic-bezier(0.2, 0, 0, 1);
  --ease-emphasized: cubic-bezier(0.2, 0.8, 0.2, 1);
}