:root {
  --bright-gutter: clamp(16px, 5.56vw, 80px);
  --bright-tile-radius: 16px;
  --bright-focus: #2044f4;
  --bright-error: #972e22;
  --bright-motion-ease: cubic-bezier(.2, .75, .25, 1);
  --bright-mono: 'JetBrains Mono', ui-monospace, monospace;
}

body { background: var(--md-surface-lowest); }
body:has(.bright-navigation[data-active]:not([data-active="home"])) { background: var(--md-surface); }

.bright-navigation,
.bright-content {
  width: min(1280px, calc(100% - 2 * var(--bright-gutter)));
  margin-inline: auto;
  min-inline-size: 0;
}
.bright-navigation {
  display: flex;
  justify-content: space-between;
  align-items: center;
  gap: 16px;
  min-height: 73px;
  border-block-end: 1px solid var(--line);
}
.bright-navigation .site-brand { font-size: 16px; min-height: 44px; }
.bright-navigation .site-brand img { width: 32px; height: 32px; }
.bright-top-nav {
  display: flex;
  align-items: center;
  gap: 24px;
  color: var(--muted);
  font-size: 14px;
  font-weight: 500;
}
.bright-top-nav a {
  position: relative;
  display: inline-flex;
  align-items: center;
  justify-content: center;
  min-height: 44px;
  color: inherit;
  text-align: center;
  text-decoration: none;
  white-space: nowrap;
  transition: color 160ms var(--bright-motion-ease);
}
.bright-top-nav a::after {
  position: absolute;
  inset: auto 0 7px;
  height: 2px;
  border-radius: 2px;
  background: currentColor;
  content: '';
  transform: scaleX(0);
  transform-origin: left;
  transition: transform 200ms var(--bright-motion-ease);
}
.bright-top-nav .bright-account-link {
  min-width: 80px;
  padding-inline: 16px;
  border: 1px solid var(--line);
  border-radius: var(--control-radius);
  color: var(--ink);
}
.bright-top-nav .bright-account-link::after { inset-inline: 12px; }
.bright-top-nav a:is([aria-current], :hover, :focus-visible) { color: var(--md-primary); }
.bright-top-nav a:is([aria-current], :hover, :focus-visible)::after { transform: scaleX(1); }
.bright-content { display: flex; flex: 1; flex-direction: column; }
.bright-content > :is(.page, .practice-page) { width: 100%; padding: 32px 0 56px; }
main#main-content:focus { outline: none; }
.bright-content > .boot-state { min-height: 55vh; }
.bright-navigation[data-active="teacher"] + .bright-content > .boot-state { max-width: 720px; }
.bright-content > .page-student { max-width: 960px; }
.bright-content > .page-narrow { max-width: 720px; }
.bright-content > .site-footer { padding-block: 18px calc(18px + env(safe-area-inset-bottom)); }
.bright-content .site-footer-inner { padding-inline: 0; }
.bright-content .site-credit { font-size: 13px; }
.bright-content :is(.button:not(.button-secondary, .button-quiet, .button-danger), .practice-button.primary):focus-visible {
  outline-color: white;
  outline-offset: -5px;
}
.bright-icon {
  display: block;
  flex: none;
  inline-size: 20px;
  block-size: 20px;
  fill: none;
  stroke: currentColor;
  stroke-width: 1.55;
  stroke-linecap: round;
  stroke-linejoin: round;
}
.bright-skip {
  position: fixed;
  z-index: 20;
  inset: 8px auto auto 8px;
  padding: 12px 16px;
  border-radius: 8px;
  color: var(--md-on-primary);
  background: var(--md-primary);
  transform: translateY(-150%);
}
.bright-skip:focus { transform: none; }
.bright-heading {
  display: flex;
  align-items: center;
  gap: 10px;
  margin: 0 0 16px;
  font-size: clamp(28px, 3.2vw, 42px);
  line-height: 1.12;
  letter-spacing: -.035em;
}
.bright-heading .bright-icon { color: var(--md-primary); inline-size: 23px; block-size: 23px; }
.bright-heading-error .bright-icon { color: var(--bright-error); }
.bright-form-bay {
  min-width: 0;
  padding: clamp(16px, 2vw, 24px);
  background: var(--surface);
  border: 1px solid var(--line);
  border-radius: var(--bright-tile-radius);
  box-shadow: var(--md-elevation-1);
}
.bright-form-bay :is(.input, input[type="password"]) { min-height: 46px; border-radius: var(--control-radius); }
.bright-form-bay [aria-invalid="true"] { border-color: var(--bright-error); }

@media (max-width: 650px) {
  .bright-navigation { flex-direction: column; align-items: start; gap: 0; padding-top: 8px; }
  .bright-top-nav { width: 100%; justify-content: space-between; gap: 4px; font-size: clamp(11px, 3.35vw, 13px); }
  .bright-top-nav .bright-account-link { min-width: 0; padding-inline: 0; border: 0; color: var(--md-primary); white-space: normal; line-height: 1.15; }
  .bright-top-nav .bright-account-link::after { inset-inline: 0; bottom: 4px; }
  .bright-content > :is(.page, .practice-page) { padding-block-start: 24px; }
}
@media (prefers-reduced-motion: reduce) {
  .bright-top-nav a, .bright-top-nav a::after { transition: none; }
}