Errata

The example and demonstration doesn't use `revert-layer` value.

In the figure width of second and third paragraphs are not the same as first one.

Regarding paragraph:
"If overflow is set to hidden, the element’s content is clipped at the edges of the element box. With the hidden value, there is no way to get at the parts of the content that are clipped off."

There is a way to get the text/content. Select 2-3 characters and press `shift+arrow down` keys the content scrolls down and you can select it.
If you set `contain: paint` then it doesn't scroll but you can still select it and copy it.

In code `.D, .I {margin-top: 1em;}` doesn't match with the figure 11-25.
It needs to be `.D, .I {margin-bottom: 1em;}`.

Regarding the paragraph
"If this were a flex-grow situation, we would simply divide 250 pixels by 5, allocating 50 pixels per growth factor. If we were to shrink that way, we would get flex items 200, 550, and 100 pixels wide, respectively. But that’s not how shrinking actually works."

The 550 value should be 450. As 200+450+100 = 750.

In following rule
```css
.three {
grid-row-start: 9;
grid-column-start: col-A -2;}
```
It needs to be `grid-row-start: 4`

In code:
```
.exel {align-self: last-baseline;}
```

value should be `last baseline`
```
.exel {align-self: last baseline;}
```

In code line:
```
.grid {display: grid; padding: 0.5em; margin: 0.5em 1em; inine-size: auto;
```

there is typo in `inine-size`.

Regarding explanation text:
"The 13-pixel bottom silver border of cell 3-3 not only overrode the top border of cell 4-3, but it also affected the layout of content within both cells and the rows that contain both cells."

The cell 3-3(#r3c3) has only 1px borders. It is actually 4-3(#r4c3) that has 13px top border.

Regarding the suggestion "One of the best known is Font Squirrel’s @Font-Face Kit Generator."
The kit generator is no longer available they took down the feature due to legal concerns.

In the code above for the figure font "Futura" is not used. It is the same code for "Vardana".

"sixth rule" should be "fifth rule"

"...in the first example...all content wraps over four lines."

Figure 11-47 in fact shows content wrapping over 6, 5 and 5 lines in the respective items. (I take 'wrapping over' to count the first line; perhaps the author does not.)

Also,
"In the second example, the first flex item...wraps the content over (roughly) half the number of lines."
In the figure, the first item wraps over two lines, and the other items over seven and eight lines. Two is not "roughly half" of seven or eight! (When I run the code into my Firefox, the line counts are 2, 8, and 9.)

I'm really enjoying the book, by the way :-)

This isn't actually an error in the printed book, but in the sample source code at github, in grid-flexible-minmax.html.
The illustration in the printed book is correct, but running the sample source code produces a misleading picture. The "1fr" column appears to be about 35px wide (instead of zero) and the "500px" column appears to be 465px wide (instead of 500px). In fact the column widths are correct; it's the dimension labelling which is creating the misleading impression. Unfortunately I can't post a screenshot to demonstrate.

The CSS shown at the foot of page 584 for items .box 4 and .box 5 does not create the output shown in Fig. 12-38 on page 585.
.box4 {grid-column: 4; grid-row: span 2 / 5;}
.box5 {grid-column: 5; grid-row: span 4 / 5;}

The CSS in the github code for Fig. 12-38 /does/ create the illustrated effect in Fig. 12-38, but this is only because the CSS in github has been altered to
.box4 {grid-column: 4; grid-row: span 4 / 5;}
.box5 {grid-column: 5; grid-row: span 6 / 5;}

In both cases the placing of the boxes can be explained simply by counting back the span length from the given end row-line (5), with no account at all taken of 'having to start within the explicit grid'. If there really is an issue about starting to count within the explicit grid, I think it needs a different example to illustrate it. If not, the explanatory text on page 585 needs revision.