:root{--collapsed: red;--expanded: green;--space: 10px}.expander[data-transitioning=true]>.expander__content{overflow:hidden}#ember-testing .expander__content{transition:max-height .1s}#ember-testing .test-internal-height{height:10px}.demo .expander[data-expanded=false]>.expander__content{border:1px solid var(--collapsed)}.demo .expander[data-expanded=true]>.expander__content{border:1px solid var(--expanded)}.demo .expander__content{transition:max-height 1s}.demo .expander__content>.expander{padding:var(--space)}