There’s extra spaces in every line.
Spaces in CSS are not always necessary. Spaces are used to make things look nicer and more organized. We can write CSS without any spaces at all, except when we’re giving multiple values to the same property.
The space between 50px and auto does need to be there. Just one space. When we use multiple values in margin, position, or other properties that accept multple values.
You can learn all these things by looking up gradient reference guides on w3 shools, MDN, or the reference site of your choice. Here are two popular reference sites you can find all you want to know about CSS as well as other languages.