HTML Body宽度在小屏设备上锁定问题求助

问题 #

个人作品集网站某页面在屏幕宽度低于940px时，页面宽度被锁定，无法随屏幕尺寸缩小，其他页面响应式表现正常。

相关代码 #

CSS #

html {
  scroll-behavior: smooth;
}

body {
  display: flex;
  flex-direction: column;
  align-items: center;
  background-color: rgba(210, 208, 208, 0.633);
  overflow-x: hidden;
  height: auto;
  width: auto;
}

.conteudo {
  display: flex;
  flex-direction: column;
  align-items: center;
  width: 45svb;
  height: auto;
  margin: 30px 30px;
}

.botao_voltar {
  display: flex;
  flex-direction: inherit;
  position: fixed;
  z-index: 30;
  align-items: flex-start;
  height: 60px;
  justify-content: center;
  width: 45vmax;
  padding: 20px 20px;
  margin-top: 30px;
  background: rgba(172, 170, 170, 0.452);
  border-radius: 80px;
  box-shadow: 0 4px 30px rgba(0, 0, 0, 0.37);
  backdrop-filter: blur(17.5px);
}

.botao_voltar button {
  border: 0;
  border-radius: 35px;
  background-color:  #FF5F1F;
  color: white;
  font-family: 'Poppins', sans-serif;
  width: 110px;
  height: 60px;
  font-weight: 700;
  font-size: 30px;
  padding: 10px 10px;
  transition: all .7s ease;
}
    
.botao_voltar button:hover {
  transform: translate3D(0,-1px,0) scale(1.20);
  box-shadow: 8px 28px 50px rgba(39,44,49,.07), 1px 6px 12px rgba(39,44,49,.04);
  transition: all .7s ease;
  cursor: pointer;
}

.corpo {
  display: flex;
  position: relative;
  flex-direction: column;
  width: 40vmax;
  padding: 50px 50px;
  margin-top: 120px;
  background: #FF5F1F;
  border-radius: 80px;
  box-shadow: 0 4px 30px rgba(0, 0, 0, 0.37);
  backdrop-filter: blur(17.5px);
}

.corpo h1 {
  text-align: start;
  font-family: monospace;
  font-size: 60px;
  font-weight: 700;
  color: rgb(252, 248, 248);
  text-wrap: balance;
}

.corpo img {
  margin-top: 50px;
  width: inherit;
  border-radius: 60px;
  object-fit: cover;
  box-shadow: 0 4px 30px rgba(0, 0, 0, 0.37);
  backdrop-filter: blur(17.5px);
}

.corpo p {
  text-align: justify;
  font-family: 'Corporate';
  font-size: 25px;
  line-height: 3.5rem;
  word-spacing: 0.5px;
  color: rgb(252, 248, 248);
  text-wrap: balance;
}

.copyright {
  display: flex;
  align-items: flex-end;
  font-size: 20px;
  font-family: "Corporate";
  color: black;
}

HTML #

<div class="botao_voltar">
  <a href="/Projetos/index.html"><button>Voltar</button></a>
</div>
<div class="conteudo">
  <div class="corpo">
    <h1>Reconhecimento Facial Usando CNN</h1>
    <img src="https://picsum.photos/300">
    <p>
      Criei este projeto simples meramente por questões didáticas
      já que estava estudando CNN (Convulational Neural Networks).
      Basicamente eu montei um modelo do zero, não utilizei nenhuma
      arquitetura pronta, como RES-NET ou ALEX-NET, ao invés montei
      eu mesmo, de forma bem amadora mas para simplesmente entender a 
      lógica por trás do CNN.
    </p>
  </div>
</div>

<p class="copyright"> © 2024 Luiz Fernando Brasão</p>

问题原因 #

1. vmax单位误用：botao_voltar和corpo的宽度使用vmax，该单位取视口宽/高中的较大值。手机竖屏时视口高度大于宽度，导致元素宽度基于高度计算，远超屏幕宽度，撑开页面。
2. svb单位兼容性问题：conteudo使用的svb是较新的CSS单位，部分浏览器对其支持不完善，计算逻辑易在小屏上导致宽度异常。
3. 固定像素尺寸溢出：标题、按钮的固定像素字体大小，在小屏上易超出容器，间接导致页面宽度被锁定。

解决方案 #

1. 替换问题单位，改用适配性更好的相对单位 #

将vmax换成vw（基于视口宽度），svb换成百分比，并添加最大宽度限制：

.conteudo {
  display: flex;
  flex-direction: column;
  align-items: center;
  width: 90%;
  max-width: 1200px;
  height: auto;
  margin: 30px auto;
}

.botao_voltar {
  display: flex;
  flex-direction: inherit;
  position: fixed;
  z-index: 30;
  align-items: flex-start;
  height: 60px;
  justify-content: center;
  width: 90vw;
  max-width: 800px;
  padding: 20px 20px;
  margin-top: 30px;
  left: 50%;
  transform: translateX(-50%);
  background: rgba(172, 170, 170, 0.452);
  border-radius: 80px;
  box-shadow: 0 4px 30px rgba(0, 0, 0, 0.37);
  backdrop-filter: blur(17.5px);
}

.corpo {
  display: flex;
  position: relative;
  flex-direction: column;
  width: 100%;
  max-width: 800px;
  padding: 30px 25px;
  margin-top: 120px;
  background: #FF5F1F;
  border-radius: 80px;
  box-shadow: 0 4px 30px rgba(0, 0, 0, 0.37);
  backdrop-filter: blur(17.5px);
}

2. 实现响应式字体大小 #

用clamp()函数让字体随屏幕宽度自动缩放，避免溢出：

.corpo h1 {
  text-align: start;
  font-family: monospace;
  font-size: clamp(2rem, 5vw, 4rem);
  font-weight: 700;
  color: rgb(252, 248, 248);
  text-wrap: balance;
}

.corpo p {
  text-align: justify;
  font-family: 'Corporate';
  font-size: clamp(1rem, 2.5vw, 1.5rem);
  line-height: clamp(1.8rem, 4vw, 3.5rem);
  word-spacing: 0.5px;
  color: rgb(252, 248, 248);
  text-wrap: balance;
}

.botao_voltar button {
  border: 0;
  border-radius: 35px;
  background-color:  #FF5F1F;
  color: white;
  font-family: 'Poppins', sans-serif;
  width: clamp(80px, 15vw, 110px);
  height: 60px;
  font-weight: 700;
  font-size: clamp(1.2rem, 3vw, 2rem);
  padding: 10px 10px;
  transition: all .7s ease;
}

3. 优化全局样式 #

确保body不会被溢出内容撑开，版权文本适配小屏：

body {
  display: flex;
  flex-direction: column;
  align-items: center;
  background-color: rgba(210, 208, 208, 0.633);
  overflow-x: hidden;
  height: auto;
  width: 100%;
  padding: 0 10px;
  box-sizing: border-box;
}

.copyright {
  display: flex;
  align-items: flex-end;
  font-size: clamp(0.8rem, 2vw, 1.2rem);
  font-family: "Corporate";
  color: black;
  margin: 20px 0;
}

内容的提问来源于stack exchange，提问作者N1ne