Are you on the Moodle Cloud platform, using the theme called MoodleCloud? Or somewhere else, using a theme called exactly "Cloud"?
Also, what version of Internet Explorer are you using?
Do you have any other blocks on the page? If you add more blocks, do they behave the same way?
What happens if you change the width of your browser? (wider, smaller)
If it is the Moodlecloud theme in Internet Explorer 11 (recent version), I would be surprised to learn that it does not elegantly work at different browser widths (but you never know). That makes me wonder if you're on a custom theme or older version browser.
Also, what version of Internet Explorer are you using?
Do you have any other blocks on the page? If you add more blocks, do they behave the same way?
What happens if you change the width of your browser? (wider, smaller)
If it is the Moodlecloud theme in Internet Explorer 11 (recent version), I would be surprised to learn that it does not elegantly work at different browser widths (but you never know). That makes me wonder if you're on a custom theme or older version browser.