[css-grid] Fix some small issues in examples

This closes issue w3c#1166.

Author: mrego

css-grid/Overview.bs

@@ -438,6 +438,7 @@ Declaring the Grid</h3>
 					@media print {
 					  main {
 					    grid: auto-flow 1fr / repeat(auto-fill, 5em);
+					  }
 					}
 				</pre>
 			<li>
@@ -490,11 +491,11 @@ Placing Items</h3>
 
 		They can further be decomposed into the 'grid-row-start'/'grid-row-end'/'grid-column-start'/'grid-column-end' longhands, e.g.
 		<pre>
-			grid-area: a; &rarr;
-			grid-row-start: a; grid-column-start: a; grid-row-end: a; grid-column-end: a;
+			grid-area: a;
+			/* Equivalent to grid-row-start: a; grid-column-start: a; grid-row-end: a; grid-column-end: a; */
 
-			grid-area: 1 / 3 / -1; &rarr;
-			grid-row-start: 1; grid-column-start: 3; grid-row-end: -1; grid-column-end: auto;
+			grid-area: 1 / 3 / -1;
+			/* Equivalent to grid-row-start: 1; grid-column-start: 3; grid-row-end: -1; grid-column-end: auto; */
 		</pre>
 	</div>
 
@@ -2507,7 +2508,7 @@ Numeric Indexes and Spans</h4>
 			.two {
 				grid-row: 2;    /* Place item in the second row. */
 				grid-column: 3; /* Place item in the third column. */
-				/* Equivalent to grid-area: 2 / 3;
+				/* Equivalent to grid-area: 2 / 3; */
 			}
 		</pre>
 	</div>
@@ -3379,7 +3380,8 @@ Aligning the Grid: the 'justify-content' and 'align-content' properties</h3>
 		<pre>
 			.wrapper {
 			  display: grid;
-			  &hellip; 4-column / 3-row grid container &hellip;
+			  /* 3-row / 4-column grid container */
+			  grid: repeat(3, auto) / repeat(4, auto);
 			  grid-gap: 10px;
 			  align-content: space-around;
 			  justify-content: space-between;