Text content, like a blog post, can have embedded elements, like images and tables.
For readability, a line of text should have a limited length, to reduce the space the eye has to jump between the end of one line and the start of the next.
To constrain the column with grid, set a max width.
.container {
display: grid;
/* Auto expand width, max 48rem */
grid-template-columns: minmax(auto, 48rem);
/* No minimum size, allow enlarging */
grid-template-columns: fit-content(48rem);
/* No minimum size, no enlarging */
grid-template-columns: max(48rem);
}Level