<!DOCTYPE html><html><metacharset="utf-8"><title>CSS Multi-column Layout Test: Test a multi-column container on button works with a column-span:all child</title><linkrel="author"title="Ting-Yu Lin"href="mailto:tlin@mozilla.com"><linkrel="author"title="Mozilla"href="http://www.mozilla.org/"><linkrel="help"href="https://drafts.csswg.org/css-multicol-1/#column-span"><linkrel="match"href="multicol-span-all-button-001-ref.html"><metaname="assert"content="This test checks the page is rendered correctly for a multi-column container on button with a column-span:all child."><style>button{column-count:3;column-rule:6pxsolid;width:400px;}h3{column-span:all;outline:1pxsolidblue;}</style><button><div>block1</div><div>block2</div><h3>spanner</h3><div>block3</div><div>block4</div></button></html>