:root {
  color-scheme: light;

  --ultt-color-canvas: #f5f7fa;
  --ultt-color-canvas-raised: #ffffff;
  --ultt-color-canvas-subtle: #eef2f6;
  --ultt-color-surface: #ffffff;
  --ultt-color-surface-muted: #f8fafc;
  --ultt-color-surface-accent: #edf7f5;
  --ultt-color-surface-warning: #fff7ed;
  --ultt-color-surface-danger: #fef2f2;

  --ultt-color-text: #17202a;
  --ultt-color-text-soft: #334155;
  --ultt-color-muted: #647084;
  --ultt-color-faint: #8a96a8;
  --ultt-color-border: #d7dee8;
  --ultt-color-border-strong: #b8c2cf;

  --ultt-color-primary: #2563eb;
  --ultt-color-primary-hover: #1d4ed8;
  --ultt-color-primary-soft: #eaf1ff;
  --ultt-color-primary-border: #b8cdfd;
  --ultt-color-primary-text: #123f93;

  --ultt-color-teal: #0f766e;
  --ultt-color-teal-hover: #0b605a;
  --ultt-color-teal-soft: #e5f5f2;
  --ultt-color-teal-border: #a9d9d2;
  --ultt-color-teal-text: #0b514d;

  --ultt-color-success: #15803d;
  --ultt-color-success-soft: #e8f6ee;
  --ultt-color-success-border: #b7dfc6;
  --ultt-color-warning: #b45309;
  --ultt-color-warning-soft: #fff3dc;
  --ultt-color-warning-border: #f4ca8a;
  --ultt-color-danger: #b42318;
  --ultt-color-danger-soft: #fff0ee;
  --ultt-color-danger-border: #efb5ae;

  --ultt-font-sans: "Avenir Next", "PingFang SC", "Hiragino Sans GB", "Microsoft YaHei", "Noto Sans SC", Arial, sans-serif;
  --ultt-font-serif: "Iowan Old Style", "Palatino Linotype", "Book Antiqua", "Songti SC", "Noto Serif SC", serif;
  --ultt-font-mono: "SFMono-Regular", Consolas, "Liberation Mono", Menlo, monospace;

  --ultt-text-xs: 0.72rem;
  --ultt-text-sm: 0.8rem;
  --ultt-text-md: 0.9rem;
  --ultt-text-base: 1rem;
  --ultt-text-lg: 1.125rem;
  --ultt-text-xl: 1.35rem;

  --ultt-line-tight: 1.2;
  --ultt-line-normal: 1.45;
  --ultt-line-relaxed: 1.65;

  --ultt-space-1: 4px;
  --ultt-space-2: 8px;
  --ultt-space-3: 12px;
  --ultt-space-4: 16px;
  --ultt-space-5: 20px;
  --ultt-space-6: 24px;
  --ultt-space-7: 32px;

  --ultt-radius-xs: 4px;
  --ultt-radius-sm: 6px;
  --ultt-radius-md: 8px;
  --ultt-radius-lg: 10px;
  --ultt-control-height-sm: 32px;
  --ultt-control-height-md: 38px;
  --ultt-control-height-lg: 44px;

  --ultt-shadow-xs: 0 1px 2px rgba(15, 23, 42, 0.06);
  --ultt-shadow-sm: 0 4px 12px rgba(15, 23, 42, 0.08);
  --ultt-shadow-md: 0 10px 28px rgba(15, 23, 42, 0.1);
  --ultt-focus-ring: 0 0 0 3px rgba(37, 99, 235, 0.22);

  --ultt-shell-max: 1440px;
  --ultt-readable-max: 760px;
  --ultt-transition-fast: 150ms ease;
}

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

.skip-link {
  position: fixed;
  top: var(--ultt-space-3);
  left: var(--ultt-space-3);
  z-index: 10000;
  min-height: var(--ultt-control-height-sm);
  padding: 7px 10px;
  border: 1px solid var(--ultt-color-primary-border);
  border-radius: var(--ultt-radius-sm);
  background: var(--ultt-color-surface);
  color: var(--ultt-color-primary-text);
  font-family: var(--ultt-font-sans);
  font-size: var(--ultt-text-sm);
  font-weight: 800;
  line-height: 1;
  text-decoration: none;
  box-shadow: var(--ultt-shadow-sm);
  transform: translateY(-140%);
  transition: transform var(--ultt-transition-fast);
}

.skip-link:focus,
.skip-link:focus-visible {
  outline: none;
  transform: translateY(0);
  box-shadow: var(--ultt-focus-ring), var(--ultt-shadow-sm);
}

main[tabindex="-1"]:focus {
  outline: none;
}

@media (prefers-reduced-motion: reduce) {
  :root {
    --ultt-transition-fast: 0ms linear;
  }
}