Check out example codes for "css grid". It will help you in understanding the concepts better.

Code Example 1

/* Answer to: "css grid mdn" */

/*
  The grid CSS property is a shorthand property that sets all of
  the explicit grid properties (grid-template-rows,
  grid-template-columns, and grid-template-areas), and all the
  implicit grid properties (grid-auto-rows, grid-auto-columns, and
  grid-auto-flow), in a single declaration.

  For more information, go to:
  https://developer.mozilla.org/en-US/docs/Web/CSS/grid
*/

Code Example 2

.item-a {
  grid-area: header;
}
.item-b {
  grid-area: main;
}
.item-c {
  grid-area: sidebar;
}
.item-d {
  grid-area: footer;
}

.container {
  display: grid;
  grid-template-columns: 50px 50px 50px 50px;
  grid-template-rows: auto;
  grid-template-areas: 
    "header header header header"
    "main main . sidebar"
    "footer footer footer footer";
}

Code Example 3

.item-a {
  grid-area: header;
}
.item-b {
  grid-area: main;
}
.item-c {
  grid-area: sidebar;
}
.item-d {
  grid-area: footer;
}

.container {
  display: grid;
  grid-template-columns: 50px 50px 50px 50px;
  grid-template-rows: auto;
  grid-template-areas: 
    "header header header header"
    "main main . sidebar"
    "footer footer footer footer";
}

Code Example 4

grid-row-start:    2;
grid-row-end:      3;
grid-column-start: 2;
grid-column-end:   3;

Code Example 5

.container {
  display: grid | inline-grid;
}

Code Example 6

/* Answer to: "css display grid" */

/*
  The CSS Grid Layout Module offers a grid-based layout system,
  with rows and columns, making it easier to design web pages
  without having to use floats and positioning.

  An HTML element becomes a grid container when its display property
  is set to grid or inline-grid.

  For more information, go to:
  https://www.w3schools.com/css/css_grid.asp
*/

.grid-container {
  display: grid;
}

/* or */

.grid-container {
  display: inline-grid;
}

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