/*
  Base reset + typography. Section 8.4 requires complete journeys at 200%
  text zoom without loss of content — font sizes here are rem-based (so
  they scale with the browser's text-zoom setting) and containers use
  min-height, not fixed height, so zoomed text can grow a box instead of
  being clipped by it.
*/
*,
*::before,
*::after {
  box-sizing: border-box;
}

html,
body,
#teach-root {
  height: 100%;
}

body {
  margin: 0;
  font-family: var(--bgt-font-stack);
  font-size: 1rem;
  line-height: 1.5;
  color: var(--bgt-color-text);
  background: var(--bgt-color-canvas);
  -webkit-font-smoothing: antialiased;
}

/* Section 4.8: "Do not encode status by color alone" — every focus
   indicator here is a visible outline, not a color swap, and every
   status affordance in this app pairs color with an icon/label, never
   color alone. */
:focus-visible {
  outline: 2px solid var(--bgt-color-accent);
  outline-offset: 2px;
}

button,
input,
select,
textarea {
  font: inherit;
  color: inherit;
}

button {
  cursor: pointer;
  min-height: var(--bgt-control-height);
  border-radius: var(--bgt-radius-small);
}

a {
  color: var(--bgt-color-accent);
}

img,
svg {
  max-width: 100%;
  display: block;
}

.bgt-visually-hidden {
  position: absolute;
  width: 1px;
  height: 1px;
  padding: 0;
  margin: -1px;
  overflow: hidden;
  clip: rect(0, 0, 0, 0);
  white-space: nowrap;
  border: 0;
}