Changing Emacs Font Colors
I prefer a white background with dark text when I work, which generally works well-enough but some modes in Emacs create foreground-background colors that make it hard to impossible to read. The simplest way that I know of to change a font's colors is with the customize-face command.
Example: Changing This Headline
The original color for this headline in rst-mode was magenta (not by default, I had changed things a couple of times).
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To change it I moved my cursor onto the headline and entered M-x customize-face.
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This brings up a prompt so you can enter the particular face you want to change. I didn't know the name that I wanted to change but since my cursor was already over the headline, it used that as the default so I could just hit enter to select it.
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As you can see the headline-face in this case is rst-level-1.
After I hit enter it took me to a dialog page to let me change the settings for this face.
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In this case I just wanted to change the background color so I clicked on the bottom Choose button. You can enter values directly if you have something in mind, but I didn't so this seemed like the easier way to do it, since it brings up a color picker which lets you see what the colors look like.
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I decided to go with deep sky blue so I moved my cursor over that row in the color picker and hit enter
. This closes the color-picker and updates the color in the customization dialog.
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This changes the dialog but doesn't actually change the settings. To do that you have to move you cursor to Apply and Save and hit enter
. This updates the sample color so you can see what it now looks like.
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When I then switched back to my original editing buffer, the headline now had a blue background.
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Which doesn't look as nice as I thought it would so I changed again. Same steps, different colors.
Describe Face
Another useful command is M-x describe-face which shows you the settings for a face. This is what it showed after I made another change to my headline color.
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If you click on customize this face up at the top-right of the window it takes you to the same dialog that the M-x customize-face command takes you to.