<!DOCTYPE html>
<html>
<head>
<title>margin-trim: flex-row-block-multiline</title>
<link rel="author" href="mailto:sammy.gill@apple.com">
<link rel="help" href="https://drafts.csswg.org/css-box-4/#margin-trim-flex">
<meta name="assert" content="block-start margins are trimmed for items on first flex line and block-end margins and trimmed for items on last flex line">
<style>
flexbox {
    display: flex;
    width: 100px;
    flex-wrap: wrap;
    gap: 20px 0px;
    border: 1px solid black;
}
item {
    displ