The default styling for Help Scout Desk is intentionally bare, the idea was that developers and designers installing it on their own site would want to make it fit within their design and having to overwrite CSS is a pain. In some cases HSD will look great right after it's installed because it's using bootstrap classes.
For some users a jumpstart is appreciated and that's why we created a new default style for Help Scout Desk, you might notice that it's very similar to our own design (which is shown in the video on the HSD page).
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The CSS below should be added to your child (or parent) theme style.css file. Hope you like it!