[Listed.to] Can't see caret on <input>s when dark mode is enabled

[kashav]

Describe the bug
When dark mode is enabled, I can't see the caret in <input>s on listed.to.

To Reproduce

1. Enable dark mode in your OS settings (or via developer tools (in Firefox at least)).
2. Open your listed.to settings page (would be kind of nice if these URLs weren't tied to specific accounts, so I could link to them).
3. Click an input. Notice that the caret is the same color as the background, which makes it hard to see where I'm typing.

Expected behavior
The caret should be the same colour as the text, so I can see where I'm typing.

Tested in Firefox and Chrome.

[kashav]

Guess this should also be filed against https://github.com/standardnotes/listed instead? (cc @vardan-arm)