How Can I Fade the Blur effect? [CSS, HTML]

On my website, I got a blured border around my images as seen:

image of my current progress

Is there any way that i can FADE the blur effect? So at the edge of the border, the effect is very subtle, but closer to the image, the effect is very strong?

Current code:

.block {
  padding: 1em;
  background-color: rgb(255, 255, 255, 0.05);
  backdrop-filter: blur(12px);
  border-radius: 5px;
}