Portfolio: Top of modal is cut off under certain conditions

[c-mauderer]

Is this a BUG REPORT or FEATURE REQUEST?:
bug

What happened:

If you click on one of the portfolio items a modal window opens. In small browser windows the top of the modal is cut off. The close button isn't reachable. The scroll bar is already all the way to the top and I can't scroll up any further.

Note that this is more likely to happen if the image is bigger then the suggested 500x380.

What you expected to happen:

I expect that I can scroll all to the top of the modal.

How to reproduce it (as minimally and precisely as possible):

Use the official Syna Example Site, open the portfolio and click on the second image. Reduce the height of your browser. See here for an example screenshot:

https://gist.githubusercontent.com/c-mauderer/e3e2cb400f4edc634ce951f336a2e24f/raw/403a1d17f74d484e3fce2b3cc040fef6701e7eed/Screenshot_20201114_190040.png

Anything else we need to know?:

Environment:

• Syna Theme version: 0.17.2; current master
• Hugo version: v0.77.0/extended linux/amd64; no idea which one is used for example site
• Others: Happens on Chromium 86.0.4240.183 and Firefox 82.0.2