Create a blog thumbnail placeholder
A 1200x630 placeholder is useful when planning social preview or blog card image areas.
Input
Width: 1200
Height: 630
Background: #cccccc
Output
https://placehold.co/1200x630/cccccc/white?text=1200x630
<img src="..." alt="Placeholder 1200x630" width="1200" height="630" />