<!DOCTYPE html>
<html>
<head>
<style>
.button {
background-color: #4CAF50;
border: none;
color: white;
padding: 15px 32px;
text-align: center;
text-decoration: none;
display: inline-block;
font-size: 16px;
margin: 4px 2px;
cursor: pointer;
}
.button2 {background-color: #008CBA;}
.button3 {background-color: #f44336;}
.button4 {background-color: #e7e7e7; color: black;}
.button5 {background-color: #555555;}
</style>
</head>
<body>
<h1>按钮颜色</h1>
<p>通过 background-color 属性改变按钮的背景色:</p>
<button class="button">绿色</button>
<button class="button button2">蓝色</button>
<button class="button button3">红色</button>
<button class="button button4">灰色</button>
<button class="button button5">黑色</button>
</body>
</html>