<!DOCTYPE html> | |
<html> | |
<head> | |
<meta name="viewport" content="width=device-width, initial-scale=1"> | |
</head> | |
<script> | |
function runTest() { | |
checkbox.indeterminate = true; | |
} | |
</script> | |
<body onload="runTest()"> | |
<input type="checkbox" id="checkbox"> | |
</body> | |
</html> |