Blog Preview card written in HTML and Css

What are you most proud of, and what would you do differently next time?

i made this thing suprisingly quickly even though i am just getting familiar with html and css so i was very happy

What challenges did you encounter, and how did you overcome them?

i could not get image inside container to have round corners,i tried border radius but for some reason it did not work,also making container centered was big problem for me , it was almost impossible to make it vertically centered so i used margin for it , even though i think it was bad idea

What specific areas of your project would you like help with?

i need ideas how to make it easier to center or move containers as i wish and also how to make images corners round , thanks in advance