Easy Themes for ProtonMail

This is a collection of simple color themes for the ProtonMail web app. 🎨


Dark Theme

Copy the CSS directly and edit the colors.


Flat Theme

Copy the CSS directly and edit the colors.


Background Image Theme

Copy the CSS directly and edit the image variable --image to your own image. Take a look at coolbackgrounds.io for awesome backgrounds.


GM Theme

Copy the CSS directly and edit the colors.



Take any theme above and you can override the theme colors with your own.

/* First paste the CSS theme. */

/* Now you can change the colors... */
:root {
    --theme1: #3652d1; /* Blue instead of Red */

And that’s it!

CSS variables make it easy to override colors. The root keyword just means it will set the variables globally. These themes have been simplified down into 7 “core” colors that make it easy to overwrite any colors of your choice. So take one of the themes above and set the colors with your own. You can also generate a pretty color palette here.

:root {
/* Core Theme Colors */
    --theme1: #66669a; /* Purple */
    --theme2: #5f5f60; /* Dark Grey */
    --theme3: #f0f0f0; /* Light Grey */
    --theme4: #bcbdbf; /* Grey */
    --theme5: #797a7c; /* Medium Grey */
    --theme6: #9397cd; /* Light Purple */
    --theme7: #fefefe; /* White */
  1. Copy a CSS theme.
  2. Paste in ProtonMail. Settings > Appearance > Custom Theme.
  3. Customize the colors (or leave default).
  4. Enjoy!


Privacy and Performance

The above code used a CSS import statement for ease of use and quickly trying out a theme. However, the CSS import statement causes files to load sequentially instead of parallel, thus slowing down your pages load performance. Also, if your privacy is of the utmost importance, then I wouldn’t use the CSS import statment from above. It potentially could reveal your behavior e.g. identifying when you load up ProtonMail using which specific theme. To avoid this, please copy & paste the entire contents of the CSS file, rather than use the import statement. This is no longer a concern, now that the Content-Security-Policy (CSP) Header blocks @import statements from loading remote content.


Spot a problem or bug? You can open an issue here.

I’ll accept pull requests to the master branch too. Please make sure to minify the CSS as well.

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