message: Use functional color variables in ProgressBar
diff: @@ -29,7 +29,7 @@ type StyledProgressContainerProps = {
  const ProgressContainer = styled.span<StyledProgressContainerProps>`
  display: ${props => (props.inline ? 'inline-flex' : 'flex')};
  overflow: hidden;
  - background-color: ${get('colors.gray.2')};
  + background-color: ${get('colors.bg.secondary')};
  border-radius: ${get('radii.1')};
  height: ${props => sizeMap[props.barSize || 'default']};
  ${COMMON}
  @@ -48,7 +48,7 @@ function ProgressBar({progress, bg, theme, ...rest}: ProgressBarProps) {
  }
  ProgressBar.defaultProps = {
  - bg: 'green.5',
  + bg: 'colors.bg.success',
  barSize: 'default',
  theme
  }
  