edit theme colours vscode code example

Example 1: visual studio code add white theme

Selecting the Color Theme#
Open the Color Theme picker with File > Preferences > Color Theme. (Code > Preferences > Color Theme on macOS).
You can also use the keyboard shortcut Ctrl+K Ctrl+T to display the picker.
Use the cursor keys to preview the colors of the theme.
Select the theme you want and press Enter.

Example 2: how can i change the color of the selection through mouse in fthe vscode

Add the following lines into "Editor: Token Color Customizations" setting, inside settings.json file.

"workbench.colorCustomizations": {
    "editor.selectionBackground": "#135564",
    "editor.selectionHighlightBackground": "#135564"
},