How to center latest posts feed on homepage (no sidebar)

Hello!

So I set my homepage with no sidebars and I want my posts' titles, featured images, and other details like the author name and date etc. to be centered (except the post excerpts). Something like this.

How do you achieve that?

Thank you so much :)

EDIT: Just found a solution for this:

.no-sidebar .site.grid-container {
    max-width: 800px;
}

.entry-header {
  text-align: center;
}

These css codes worked well on what I want to achieve except for the READ MORE button. It is still left-aligned. How do I center it? Thank you!

Rob