index.html

<style>
 body {
   padding:25px;
   background-color: black;
   color: white;
   font-size: 15px;
 }

 .light-mode {
   background-color: white;
   color: black;
 }
 .top-part {
	width: 120px;
    overflow: scroll;
    border: 0px;
    clear: both;
    float: right;
 }
 .gameSelector {
 	width: 720px;
    overflow: scroll;
    border: 0px;
    clear: both;
    float: left;
   }
</style>
<div class="top-part">
<button onclick="DarkModeSwitcher()">Toggle dark mode</button>
</div>

<script>
 function DarkModeSwitcher() {
   var element = document.body;
   element.classList.toggle("light-mode");
 }
</script>

<h>Welcome To My Site!</h>
<p>There Is Mostly Minecraft Here, I May Change That In The Future! <b>Warning : This Site Is Still A WIP. Things May Change In The Future!</b></p>

<div class="gameSelector">
<a id="mclink" href="https://o-gui-blindao.github.io/index1" style="display: none;"></a>

<button onclick="MinecraftRedirect()">Minecraft Online (Eaglercraft)</button>
</div>

<script>
 function MinecraftRedirect() {
  var mclink = document.getElementById("mclink").href;
  window.location.href = mclink;
 }
</script>