调整窗口大小时如何让页面内容自动适配 修复背景适配异常问题

问题根源 #

• 背景无法适配视口：html和body未设置占满视口高度，background-size使用auto只会按原图尺寸渲染，同时未配置背景居中规则。
• 缩放时出现无限横向延伸线条：标题样式.mchead设置了width: 200%，文本容器.mcp使用固定值left: 500px偏移，两个元素均会超出视口宽度，触发横向溢出，就会出现延伸横线和横向滚动条。

修复步骤 #

1. 新增全局基础样式 #

首先重置默认边距，配置html和body占满视口，禁止横向溢出，同时新增viewport元标签适配移动端：

* {
  margin: 0;
  padding: 0;
  box-sizing: border-box;
}
html, body {
  height: 100%;
  overflow-x: hidden;
}

2. 修复背景适配规则 #

修改.minecraftbody的背景配置，让背景铺满视口且居中：

.minecraftbody {
  background-image: url(https://www.startpage.com/av/proxy-image?piurl=https%3A%2F%2Fwallpaper-house.com%2Fdata%2Fout%2F8%2Fwallpaper2you_213216.jpg&sp=1637611406T358bfd9113b26feaf1742f91b1f8cc55007334c10b4ecebee265c9435d20b5f9);
  background-repeat: no-repeat;
  background-size: cover;
  background-position: center center;
  background-attachment: fixed; /* 可选，滚动页面时背景固定，体验更好 */
}

3. 修复元素溢出问题 #

修改标题样式

删掉.mchead里的width:200%、height:200%和相对定位偏移，用边距调整位置：

.mchead {
  font-family: 'Lora', serif;
  color: white;
  margin: 26px 0 0 90px;
}

修改文本容器样式

去掉固定left偏移，设置百分比宽度，添加你需要的蓝色背景，实现自适应：

.mcp {
  color: black;
  border: 5px solid #000;
  width: 60%;
  margin: 30px 5% 30px auto;
  padding: 20px;
  background-color: #b3d9ff; /* 可自行调整蓝色深浅 */
}
/* 新增图片自适应规则，避免图片超出容器 */
.mcp img {
  max-width: 100%;
  height: auto;
  margin-top: 15px;
}

完整修改后代码 #

<!DOCTYPE html>
<html lang="en">
<head>
  <title>Minecraft</title>
  <meta charset="UTF-8">
  <meta name="author" content="My Name">
  <meta name="keywords" content="HTML, CSS, JavaScript">
  <meta name="viewport" content="width=device-width, initial-scale=1.0">
  <link rel="stylesheet" href="style.css">
  <style>
    @import url('https://fonts.googleapis.com/css2?family=Lora:ital,wght@1,700&display=swap');
    * {
      margin: 0;
      padding: 0;
      box-sizing: border-box;
    }
    html, body {
      height: 100%;
      overflow-x: hidden;
    }
    .Gaming {
      font-family: 'Lora', serif;
      color: red;
    }
    .border {
      background-color: white;
      margin: 30px;
      padding: 20px;
      position: relative;
      border: 5px solid;
      width: 50%;
      height: 50%;
    }
    .ave {
      width: 25%;
      height: 50;
    }
    .app {
      width: 60%;
      height: 60%;
    }
    .minecraftbody {
      background-image: url(https://www.startpage.com/av/proxy-image?piurl=https%3A%2F%2Fwallpaper-house.com%2Fdata%2Fout%2F8%2Fwallpaper2you_213216.jpg&sp=1637611406T358bfd9113b26feaf1742f91b1f8cc55007334c10b4ecebee265c9435d20b5f9);
      background-repeat: no-repeat;
      background-size: cover;
      background-position: center center;
      background-attachment: fixed;
    }
    .homebg {
      background-image: url(https://images.unsplash.com/photo--82d13781b33a?ixlib=rb-1.2.1&ixid=MnwxMjA3fDB8MHxwaG90by1wYWdlfHx8fGVufDB8fHx8&auto=format&fit=crop&w=872&q=80);
      background-size: auto;
    }
    .mchead {
      color: white;
      margin: 26px 0 0 90px;
      font-family: 'Lora', serif;
    }
    .mcp {
      color: black;
      border: 5px solid #000;
      width: 60%;
      margin: 30px 5% 30px auto;
      padding: 20px;
      background-color: #b3d9ff;
    }
    .mcp img {
      max-width: 100%;
      height: auto;
      margin-top: 15px;
    }
  </style>
</head>
<body class='minecraftbody'>
  <h1 class="mchead">MINECRAFT</h1>
  <div class="mcp">
    <p>Minecraft is one of my favorite games ever since I was still a child. I made many friends through it and <br> countless memories was and are being made.</p>
    <br><br><br>
    <p>This is a picture of one of my servers that me and my friends made in Minecraft. <br> We had so much fun making this house and I still come back to this place everytime I feel nostalgic <br> about my past</p>
    <img src="Images/Mc_server.png" alt="minecraft server">
  </div>
</body>
</html>

内容的提问来源于stack exchange，提问作者H2WO