Blurry Logo Image on Mobile (Five Template)

To replace the automatic typed/font logo that appears on Five's mobile mode with the same image logo that appears on desktop, I was previously given and inserted this code several years ago:

#mobile-navigation-title {
      background: url("https://images.squarespace-cdn.com/content/55da8e05e4b090d16427e820/6d86511d-e352-404a-8c5e-3df3ea2baa8a/SigMossMobile225.png?content-type=image%2Fpng") no-repeat center;
      text-indent: 100%;
      min-height: 60px;
  }

It always showed as a bit blurry and not as crisp as it shows on desktop but I just left it. I'm tired of it looking blurry and would be grateful for a fix.

I have tried replacing the image file with larger sized ones, but that simply changes the size of the image on the screen. The current mobile logo image is 225 x 52px and shows at the appropriate size, just blurry.  Is there a way to make it appear more crisp?

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