[css-grid] Fix typo #8316

Author: fantasai

css-grid-1/Overview.bs

@@ -968,7 +968,7 @@ Limiting Large Grids</h3>
 	Since memory is limited,
 	UAs may clamp the possible size of the <a>implicit grid</a>
 	to be within a UA-defined limit
-	(which should accommodate lines at in the range [-10000, 10000]),
+	(which should accommodate lines in the range [-10000, 10000]),
 	dropping all lines outside that limit.
 	If a grid item is placed outside this limit,
 	its grid area must be <a>clamped</a> to within this limited grid.

css-grid-2/Overview.bs

@@ -1016,7 +1016,7 @@ Limiting Large Grids</h3>
 	Since memory is limited,
 	UAs may clamp the possible size of the <a>implicit grid</a>
 	to be within a UA-defined limit
-	(which should accommodate lines at in the range [-10000, 10000]),
+	(which should accommodate lines in the range [-10000, 10000]),
 	dropping all lines outside that limit.
 	If a grid item is placed outside this limit,
 	its grid area must be <a>clamped</a> to within this limited grid.