how to change css property using javascript on button click code example

Example 1: how to detect a button click in javascript

if(document.getElementById('button').clicked == true)
{
   alert("button was clicked");
}

Example 2: how to open a new html page on button click in javascript

<button id="myButton" class="float-left submit-button" >Home</button>

<script type="text/javascript">
    document.getElementById("myButton").onclick = function () {
        location.href = "www.yoursite.com";
    };
</script>