The problem is that the browser displays a border around this image. To remove the border in HTML/CSS, you need to change the required attributes. In this case you will have to set the attribute of ...

in that while it parses and renders HTML and CSS with JPEG and PNG image support, it does so only with a subset of HTML and is not tolerant of any malformations. There is also no JS support ...

Low-quality image placeholders (LQIPs ... How about trigonometric functions in CSS? Or from the other direction, check out implementing a CSS (and HTML) renderer on an ESP32.

jsFiddle is the perfect solution; it provides a custom environment (based on user selections) to test (or fiddle with) your JavaScript, HTML, and CSS code right inside your browser. A quick tour ...

The new release brings improvements to JavaScript heap profiles, CSS code formatting ... the semantic highlighting of JavaScript source in HTML files with what is seen in normal .jscode files.