如何在HTML中定位按钮的位置？

<style>
    .button {
        position: relative;
        top: 20px;
        left: 50px;
    }
</style>

<button class="button">按钮</button>

<style>
    .button {
        position: absolute;
        top: 100px;
        left: 200px;
    }
</style>

<button class="button">按钮</button>

<style>
    .button {
        position: fixed;
        top: 50px;
        right: 50px;
    }
</style>

<button class="button">按钮</button>