Bootstrap Theme
Style the uploader to match a Bootstrap-based application using CSS variable overrides.
What you should see: the same uploader wearing Bootstrap's palette and border radius, driven entirely by CSS variables. No Bootstrap JavaScript is involved. The cap is 10 MB.
Drag & drop files here, or paste from clipboard
<div style="--cu-primary: #0d6efd;
--cu-radius: 0.375rem;
--cu-btn-bg: #0d6efd;
--cu-btn-text: #ffffff;
--cu-btn-hover-bg: #0b5ed7;
--cu-border: #dee2e6;
--cu-bg: #ffffff;
--cu-text: #212529;
--cu-progress-bg: #0d6efd;">
<core-upload asp-upload-url="/api/upload/upload"
asp-multiple="true"
asp-progress="true"
asp-drop-zone="true"
asp-max-size="10MB">
</core-upload>
</div>Matching a CSS framework
The rendered markup carries stable class names, so mapping them onto Bootstrap's is a stylesheet rather than a configuration exercise. Nothing about the component needs to know which framework the surrounding page uses.
What to keep when restyling
Two states carry meaning rather than decoration: the drag-over highlight on the drop zone, and the visual difference between a completed file and a failed one. Both are easy to lose when swapping in a framework's neutral card styles, and both are exactly the moments the user needs the interface to be unambiguous.