What's changed:

This patch introduces several improvements to different components.

[Window > Title Bar]

• Added disabled minimise button.
• Added disabled close button.

• Removed the subtle blue glow from the disabled maximise button.

[Text box]

• Tweaked the colours of the text box.
• Added transition animations when it's hovered and focused.
• Added disabled style.

[Radio Button]

• Added disabled style.
• Fixed hover style is visible in the disabled radio button.

[Slider]

• Added hover style (resolved Slider hover effect doesn't work #116).
• Added disabled style.
• Added a subtle drop shadow for the slider indicator.

[Misc.]

• Changed the disabled dropdown docs because the old one could be taken the wrong way or might sound offensive to some people 👀
• Fixed a visual bug for the check box item in the Menu component caused by my previous PR.

Please let me know if there's any issue.