:root {
  font-family: "IBM Plex Sans", "Helvetica Neue", Arial, sans-serif;
  line-height: 1.5;
  font-weight: 400;

  color-scheme: light dark;
  color: var(--c-white);
  background-color: var(--c-bg);

  font-synthesis: none;
  text-rendering: optimizeLegibility;
  -webkit-font-smoothing: antialiased;
  -moz-osx-font-smoothing: grayscale;
}

a {
  font-weight: 500;
  color: var(--c-grayL);
  text-decoration: inherit;
}
a:hover {
  color: var(--c-white);
}

body {
  margin: 0;
  display: flex;
  place-items: center;
  min-width: 320px;
  min-height: 100vh;
}

h1 {
  font-size: 3.2em;
  line-height: 1.1;
}

button {
  border-radius: 8px;
  border: 1px solid transparent;
  padding: 0.6em 1.2em;
  font-size: 1em;
  font-weight: 500;
  font-family: inherit;
  background-color: var(--c-btnBg);
  color: inherit;
  cursor: pointer;
  transition: border-color 0.15s;
}
button:hover {
  border-color: var(--c-purpleDim);
}
/* Keep an accessible focus ring, but not the white flash on mouse click.
   Base :focus ring is the fallback for browsers WITHOUT :focus-visible support
   (keyboard users still get a ring there); modern browsers then suppress it for
   non-keyboard (mouse/programmatic) focus via :focus:not(:focus-visible), so
   clicking a button (example questions, ENTER/CLEAR) no longer flashes an
   outline while keyboard navigation keeps it. */
button:focus {
  outline: 2px solid var(--c-accent);
  outline-offset: 2px;
}
button:focus:not(:focus-visible) {
  outline: none;
}

/* Theme colours come from the --c-* tokens (GlobalStyles), so no light-scheme override. */