CSS Masonry Layout Attempts

I spent two days investigating this and could not find a solution that worked. Eventually, I gave up and added the Masonry Javascript library. My two attempts were as follows:

Using CSS Columns

CSS Columns enabled an easy, powerful way to spread page summaries across multiple columns. Furthermore, you can prevent page summaries from being broken up in the middle by using column-break-inside: avoid;. However, I had no way to order the page summaries dynamically such that the most recent summaries were at the top (from left to right) and older summaries were found further down. Instead, this resulted in the latest summary starting in the top left with older summaries going down the first column and into the second, etc.

.page-summary-container {
    -moz-column-count: 3;
    -webkit-column-count: 3;
    column-count: 3;

    -moz-column-gap: 0;
    -webkit-column-gap: 0;
    column-gap: 0;

.page-summary {
    display: inline-block;
    -webkit-column-break-inside: avoid; /* Chrome, Safari */
    page-break-inside: avoid;           /* Theoretically FF 20+ */
    break-inside: avoid-column;         /* IE 11 */

Using Flexbox

This involved using flexbox to simulate a Masonry layout by using flex-flow: column wrap to have items flow from top to bottom with no extra spacing (similar to Masonry). There were two issues with this approach: page summaries still flowed from top to bottom instead of left to right and I couldn’t control wrapping the column into the next column without providing a fixed-height container.

The first issue was able to be solved by swapping the order of the elements, which you can do in flexbox. Since the list page is using pagination (meaning that I can guarantee the total page summaries per page), ordering the elements was as simple as adding child selectors to break up the order based on the number of elements:

.page-summary:nth-child(3n+1) {
    order: 1;

.page-summary:nth-child(3n+2) {
    order: 2;

.page-summary:nth-child(3n) {
    order: 3;

Unfortunately, as I couldn’t provide a fixed-height container, the column approach did not work as all elements stayed in the first column. I could not find any working way to forcefully wrap flexbox elements after a certain element when using column as the flow instead of row (where you can set the row item to a width of 100%).

I could have forced a specific height for the page summaries as I know how big the text will be (roughly) if I use an ellipsis for overflow on the title (and the summary is always 70 words max). However, the optional image throws off my sizing estimates.