Header background color only behind text for reading mode

[AllPaintedGold]

this is what i want for reading mode.

is this possible for reading mode ?

[ariehen]

For help, especially appearance questions, it’s best to share what theme and/or custom snippets you are currently using and what you have tried so far. It makes it easier for others to offer assistance.

You could try something like this

:is(h1,h2,h3,h4,h5,h6) {
    padding: 3px;
    border-radius: 6px;
    width: fit-content;
    background-color: salmon;
}

[AllPaintedGold]

thanks a lot it works.