Bootstrap 5：如何约束图片宽高、位置并实现响应式？

针对你的需求，我们可以通过Bootstrap内置工具类和少量自定义样式实现，具体调整如下：

1. 修复容器基础错误 #

原代码中第二部分容器的id与class写法混淆，需拆分定义：

<!-- 错误写法 -->
<div id="second-section position-relative">

<!-- 正确写法 -->
<div id="second-section" class="position-relative">

2. 实现图片响应式与固定位置 #

• 用Bootstrap的img-fluid类让图片自适应屏幕宽度，保持比例
• 移除原#second-section的position: absolute，改用position: relative避免布局错乱，保留margin-top控制与上方轮播的间距
• 添加z-index确保图片在轮播上方显示

3. 在图片上方添加文字 #

在图片容器内嵌套绝对定位的文本容器，通过自定义样式控制位置与可读性，文本会随图片同步响应屏幕变化。

修改后的完整代码 #

<!DOCTYPE html>
<html>

<head>
  <title>South Yorkshire RPC</title>
  <link href="https://cdn.jsdelivr.net/npm/bootstrap@5.2.0-beta1/dist/css/bootstrap.min.css" rel="stylesheet" integrity="sha384-0evHe/X+R7YkIZDRvuzKMRqM+OrBnVFBL6DOitfPri4tjfHxaWutUpFmBp4vmVor" crossorigin="anonymous">

  <!--Font Awesome-->
  <script src="https://kit.fontawesome.com/b5212ab333.js" crossorigin="anonymous"></script>

  <!-- JavaScript Bundle with Popper -->
  <script src="https://cdn.jsdelivr.net/npm/bootstrap@5.2.0/dist/js/bootstrap.bundle.min.js" integrity="sha384-A3rJD856KowSb7dwlZdYEkO39Gagi7vIsF0jrRAoQmDKKtQBHUuLZ9AsSv4jD4Xa" crossorigin="anonymous"></script>

  <style type="text/css">
    #logo-space {
      display: block;
      margin: 0 auto;
      background-color: #0f2471;
    }
    
    #jumbotron {
      margin-top: -50px;
      background-image: url("img/img-1.png");
    }
    
    #logo-space img {
      width: 20rem;
      padding: 25px;
      position: relative;
      left: 45px;
    }
    
    .nav-bar {
      background-color: #16377e;
      position: relative;
    }
    
    .navbar-element-left {
      position: relative;
      left: 50px;
      font-weight: bold;
      padding-right: 15px;
    }
    
    .navbar-element-right {
      position: relative;
      right: 50px;
      font-weight: bold;
      padding-left: 15px;
    }
    
    /* 调整第二部分容器样式 */
    #second-section {
      width: 100%;
      margin-top: -180px;
      position: relative;
      z-index: 10;
    }
    
    /* 图片上方文本样式 */
    .overlay-text {
      position: absolute;
      top: 30px;
      left: 50px;
      color: #fff;
      font-size: 1.8rem;
      font-weight: 700;
      text-shadow: 0 2px 4px rgba(0,0,0,0.7);
    }
    
    #about {
      margin-top: -50px;
      background-image: url("img/l3.png");
    }
    
    .carousel-item {
      height: 50rem;
    }
  </style>
</head>

<body>
  <div id="logo-space">
    <a class="navbar-brand" href="#"><img src="img/logo.png"></a>
  </div>

  <div id="home">
    <nav id="navbar" class="navbar navbar-expand-lg nav-bar">
      <div class="container-fluid">
        <button class="navbar-toggler" type="button" data-bs-toggle="collapse" data-bs-target="#navbarSupportedContent" aria-controls="navbarSupportedContent" aria-expanded="false" aria-label="Toggle navigation">
            <span class="navbar-toggler-icon"></span>
          </button>
        <div class="collapse navbar-collapse" id="navbarSupportedContent">
          <ul class="navbar-nav me-auto mb-2 mb-lg-0">
            <li class="nav-item">
              <a class="nav-link active text-white navbar-element-left" aria-current="page" href="#home">HOME</a>
            </li>
            <li class="nav-item">
              <a class="nav-link text-white navbar-element-left" href="#about">ABOUT US</a>
            </li>
            <li class="nav-item">
              <a class="nav-link text-white navbar-element-left" href="#divisions">DIVISIONS</a>
            </li>
            <li class="nav-item">
              <a class="nav-link text-white navbar-element-left" href="#appeals">APPEALS</a>
            </li>
            <li class="nav-item">
              <a class="nav-link text-white navbar-element-left" href="#feed">FEED</a>
            </li>
          </ul>
          <span class="navbar-text">
                <a class="nav-link text-white navbar-element-right" href="#application">APPLY NOW</a>
            </span>
        </div>
      </div>
    </nav>
  </div>

  <div id="carouselExampleSlidesOnly" class="carousel slide" data-bs-ride="carousel">
    <div class="carousel-inner">
      <div class="carousel-item active">
        <img src="img/img-1.png" class="d-block w-100" alt="...">
      </div>
      <div class="carousel-item">
        <img src="img/img-2.png" class="d-block w-100" alt="...">
      </div>
      <div class="carousel-item">
        <img src="img/img-3.png" class="d-block w-100" alt="...">
      </div>
    </div>
  </div>

  <!-- 修改后的第二部分容器 -->
  <div id="second-section" class="position-relative">
    <img src="img/l3.png" class="img-fluid w-100" alt="Section Image">
    <!-- 图片上方的文本 -->
    <div class="overlay-text">
      这里是你要添加的自定义文字
    </div>
  </div>
</body>

</html>

关键说明 #

• img-fluid：保证图片自动适配容器宽度，实现响应式缩放
• position-relative：为文本的绝对定位提供参考基准
• overlay-text：可根据需求调整top/left值改变文本位置，修改字体样式适配你的设计

内容的提问来源于stack exchange，提问作者Welshy