You’re actually seeing the top margin of the #inner element collapse into the top edge of the #outer element, leaving only the #outer margin intact (albeit not shown in your images). The top edges of both boxes are flush against each other because their margins are equal. Here are the relevant points from the W3C … Read more
Add overflow:auto to your #page div. jsFiddle example And check out collapsing margins while you’re at it.
TL;DR: By default I use margin everywhere, except when I have a border or background and want to increase the space inside that visible box. To me, the biggest difference between padding and margin is that vertical margins auto-collapse, and padding doesn’t. Consider two elements one above the other each with padding of 1em. This … Read more
check this int dpValue = 5; // margin in dips float d = context.getResources().getDisplayMetrics().density; int margin = (int)(dpValue * d); // margin in pixels