message: transition the color as well
diff: @@ -13,7 +13,7 @@ const ArrowProject = styled.span`
  background-color: ${props => props.isActive ? "#40A6FF" : "#505050"};
  display: inline-block;
  transform: ${props => props.isActive ? "rotate(0deg)" : "rotate(-90deg)"};
  - transition: transform 100ms linear;
  + transition: all 100ms linear;
  }
  `;
  