| <!doctype html> |
| <title>CSS Values and Units Test: rem units on the root element</title> |
| <link rel="help" href="https://drafts.csswg.org/css-values/#rem"> |
| <script src="/resources/testharness.js"></script> |
| <script src="/resources/testharnessreport.js"></script> |
| <style> |
| :root { |
| font-size: 50px; |
| margin-left: 2rem; |
| padding-top: 2rem; |
| line-height: 2rem; |
| } |
| </style> |
| <script> |
| let rootStyle = getComputedStyle(document.documentElement); |
| test(() => assert_equals(rootStyle.marginLeft, "100px"), "rem based margin."); |
| test(() => assert_equals(rootStyle.paddingTop, "100px"), "rem based padding."); |
| test(() => assert_equals(rootStyle.lineHeight, "100px"), "rem based line-height."); |
| |
| test(() => { |
| document.documentElement.style.fontSize = "initial"; |
| let initialFontSize = parseInt(getComputedStyle(document.documentElement).fontSize); |
| document.documentElement.style.fontSize = "3rem"; |
| assert_equals(getComputedStyle(document.documentElement).fontSize, 3*initialFontSize + "px"); |
| }, "Check that rem font-size is based on the initial font-size."); |
| </script> |