class in a div after img src

Question

Hi, I`m new in programing at all and I try to extract as more information about. During some practice in a video lessons I was stacked in this point:
Into a index.html page is placed an example:
<div><img src="img/example.gif" class:"bordered-image simple-form"/></div>
And in my Notepad++ the class:"bordered-image simple-form" string is not colored. Then when I check and type like in the example of the teacher in css file everywhere where there is a ".bordered-image" and ".simple form" strings they are colored in red. And nothing is right shown like in the example. I`m soo confused because checked 1000 times for typos and saw the lesson a lot of times. Please if somebody can help I would be very thankful. I guess it is a conceptual error somewhere on the way.

Answer 1

Maria

class="something" not class:"something"
https://www.w3schools.com/html/html_classes.asp

Answer 2

class="bordered-image simple-form" put this inside of your img tag.

Answer 3

Thank you ODLNT, but if you look at this code:
<div><img src="img/example.gif" class:"bordered-image simple-form"/></div>
you`ll see that class="bordered-image simple-form" is already put into an image tag? Or I can`t understand you clearly?