Review my Cheat sheet

Not done completely just need a couple more but i want someone to review my code to see if im going in the right direction

<!DOCTYPE html>
<html lang="en">
    <link rel="stylesheet" href="./resources/index.css" type="text/css">
    <meta charset="UTF-8">
    <meta http-equiv="X-UA-Compatible" content="IE=edge">
    <meta name="viewport" content="width=device-width, initial-scale=1.0">
    <title>Common Css properties</title>
        <h1> Common CSS Properties</h1>
        <div class="table">
                        <td>text-align: center;</td>
                        <td>It aligns the text to what ever is the selected selector</td>
                        <td>color: blue;</td>
                        <td>changes the color of the selector</td>
                        <td>font-size: 30px;</td>
                        <td>is used to set text sizes. Font size values can be many different units or types such as pixels.</td>
th, td {
    border: 2px solid green;
    background-color: yellow;
    border: 2px solid grey;
    text-align: center;
    border-collapse: collapse;
    font-weight: bold;
    text-align: center;
    position: relative;
    left: 500px;

also how can I make my table be positioned in the middle with out the padding property