> ## Documentation Index
> Fetch the complete documentation index at: https://learn.biq.li/llms.txt
> Use this file to discover all available pages before exploring further.

# Customize and download a link QR code

> Style and export the QR code attached to a short link.

Open the link's QR code to customize its matrix, eye frame, eye style, colors, gradient, and supported logo option. Use the preview after every major style change.

Keep strong contrast between the code and background. When **Apply to all** is selected for the matrix, its color treatment also controls the eye frame and eye. When selected for the eye frame, it also controls the eye.

Download the final image only after testing it with more than one phone or scanning application.

## Style without reducing reliability

Choose a matrix and eye shape, then configure solid colors or a supported
gradient. A gradient includes start and end colors, direction, and midpoint.
Keep the dark modules clearly separated from the background.

If the matrix uses **Apply to all**, its color controls the matrix, eye frame,
and eye. If the eye frame uses **Apply to all**, it also controls the eye. The
dependent color controls are disabled so the saved style remains consistent.

Show or hide the supported logo according to the editor and plan. Keep logos
small enough for error correction to preserve the code.

Before downloading, scan the preview at several sizes. After downloading, test
the actual file and a print proof. Avoid cropping the quiet margin, stretching
the image, or applying heavy compression.

## Frequently asked questions

### Why are eye color controls disabled?

An apply-to-all option is making them inherit another component's colors.

### Does a style update affect old files?

No. Download and distribute the newly rendered image.

### Can the API upload a custom logo?

No. The current public QR API supports documented logo visibility but rejects
custom logo uploads.