JSFiddle - React, Tailwind, and code Playground

HTML

<div id="backpack" style="height:400px; width:400px; border-style:solid; border-width:8px; position:absolute; top:92px; left:192px"></div>

JavaScript

var invName = ["donut", "sword", "donut", "sword", "empty", "empty", "empty", "empty", "empty"];
var invType = ["usable", "equipment", "usable", "equipment", "empty", "empty", "empty", "empty", "empty"];
var invValue = [1, 0, 1, 0, 0, 0, 0, 0, 0];

			function backpack(update){
				i = 0;
				if(update != 1){
                    /*
					tempA = document.getElementById("scene").innerHTML;
					tempB = document.getElementById("textbox").innerHTML;
                    */
				}
    			/*
				document.getElementById("textbox").innerHTML = '<br><br><input type="button" value="Close Backpack" onclick="closeBackpack()">';
				document.getElementById("scene").innerHTML = '<div id="backpack" style="height:400px; width:400px; background-image:url(files/sugame/sprites/backpackBackground.png); border-style:solid; border-width:8px; position:absolute; top:92px; left:192px"></div>';
                */
				for(i = 0; i <9; i++){
					if(invType[i] != "empty"){
						switch(i){
							case 0:
								document.getElementById("backpack").innerHTML += '<input type="button" value="'+ invName[i] +'" id="'+ i +'" style="position:absolute; left:4px; top:4px;">';
								break;
							case 1:
								document.getElementById("backpack").innerHTML += '<input type="button" value="'+ invName[i] +'" id="'+ i +'" style="position:absolute; left:136px; top:4px;">';
								break;
							case 2:
								document.getElementById("backpack").innerHTML += '<input type="button" value="'+ invName[i] +'" id="'+ i +'" style="position:absolute; left:268px; top:4px;">';
								break;
							case 3:
								document.getElementById("backpack").innerHTML += '<input type="button" value="'+ invName[i] +'" id="'+ i +'" style="position:absolute; left:4px; top:136px;">';
								break;
							case 4:
								document.getElementById("backpack").innerHTML += '<input type="button" value="'+ invName[i] +'" id="'+ i +'" style="position:absolute; left:136px; top:136px;">';
								break;
							case...