Here's the table cell: https://developers.google.com/+/web/share/#sharelink-sizes
As you see when you use the inspect element feature in Chrome or Firefox, the total width and height of the table cell is calculated as 105px × 85px. However, the cell content (image) is only 64px × 64px and the cell padding is 6px 10px 6px 10px. I don't see any width and height properties in the element style, so where does this extra width and height come from?
It's a table cell, so the browser will automatically distribute space among the cells to fill the width of the table. The exact width will depend upon the contents of all the cells and the width of the table. In this case, the table is set as a percentage width of the browser window, so on my 1920x1080 monitor, it's actually quite a bit bigger than in your screenshot.
来源：https://stackoverflow.com/questions/19698333/table-cell-box-model-extra-width-and-height