ROLL

roll. now with figures and figcaptions instead of divs and divs. remember to view source. i figured out why caption didn't work: caption is for tables, not for figures. the correct element is figcaption.

roll:

setting alt text, even just empty alt text, is an accessibility thing. it's *technically* required, in the sense that the web standards command that a page is not 'correct' if it doesn't have alt text, but no browser is going to break for lack of alt text. also stuff like the internet archive or google can't see the pictures but can see the alt text. it doesn't have to be fancy tho, it can be just 'frame 0' or 'animation' or 'animation of link rolling' or 'animation of glitch'. for simple decoration, which means nothing, you can even just type alt='', because the default alt text (when there -- incorrectly -- is none) is the filename, which is kind of jarring.
Placeholder 1
Frame 0
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End
Placeholder 3
Figure with a figure caption that's wider than the figure.
Placeholder 3
Another long figcaption, but this time I set max-width in CSS, for this element only.

The relevant HTML and CSS

img {
  width: 100px;  /* You don't need to set 'width="100" height="100"' on your img elements if you set it in CSS. */
  height: 100px;
}
figure {
  margin: 4px; /* default side margin is 40 px, top and bottom margin is 16 px (or 1 em) */
  display: inline-block; /* important */
  text-align: center;
}

<figure>
  <img src="/img/divmod256.png" alt="Placeholder"/>
  <figcaption class="desc">Caption</figcaption>
</figure>