As a Developer I want to change button a bit [OS-63]

[Tima0203]

• change button borders and colors according to trade.opium.exchange
  • need light and dark versions
  • be careful with change colors, so it will not break everything
  • yesterday we change tabs and tables theme, check them out

[Tima0203]

Additional changes

• round the angles a bit to make it look like Widget
• make active tab text color blue like header in both themes