网站上传至主机后Chrome端Header与响应式导航栏显示异常求助

网站上传至Web主机后，在Google Chrome访问时，Header与响应式导航栏表现不符合预期：大屏设备本应显示常规菜单、移动端隐藏常规菜单并显示汉堡菜单，但实际两个菜单同时显示。本地打开文件时一切正常，已检查选择器、属性值及兼容性，仍未定位问题。

代码片段 #

JavaScript #

function showResponsiveMenu() {
  var menu = document.getElementById("topnav_responsive_menu");
  var icon = document.getElementById("topnav_hamburger_icon");
  var root = document.getElementById("root");
  if (menu.className === "") {
    menu.className = "open";
    icon.className = "open";
    root.style.overflowY = "hidden";
  } else {
    menu.className = "";
    icon.className = "";
    root.style.overflowY = "";
  }
}

CSS（含Sass变量） #

/* CSS HEADER CODE */
.title{
  font-family: 'lemon_milkbold_italic', 'Times New Roman', 'Arial', serif;;
  font-size: 150%;
  text-shadow: 0.01rem 0.01rem $menu-color;
  color: white;
  background-color: $p-header-color;
  margin-top: -40px;
  margin-left: -8px;
  height: 85px;
  width: 100%;
  z-index: 1;
  position: absolute;
  display: block;
  overflow: hidden;

    &:before, &:after{
      content: '';
      position: absolute;
      top: 0; right: 0;
      height: 100%;
      z-index: 1;
      clip-path: polygon(35% 0, 100% 0%, 100% 100%, 0% 100%);
    }

    &:before {
      background-color: white;
      animation: showText 1200ms ease-in-out;
    }

    &:after {
      background-color: $menu-color;
      animation-delay: 500ms;
      animation: showText 1000ms ease-in-out;
    }

    h1{
      opacity: 0;
      animation: animateText 1000ms forwards;
    }
}

@keyframes animateText {
  from {
    opacity: 0;
  }
  to {
    opacity: 1;
  }
}

@keyframes showText{
  0% {
    width: 0;
    left: 0;
    transform: translateX(0);
  }
  50% {
    width: 100%;
    transform: translateX(12%);
  }
  100% {
    transform: translateX(100%);
  }
}

/* CSS NAVBAR CODE */

nav {
  font-size: 2em;
  float: left;
  width: 185px;
  height: 100%;
  text-align: center;
  color: black;
}

nav a {
  background-color: $menu-color;
  text-decoration: none;
  color: black !important;
  transform: scale(1);
  transition-property: transform;
  transition: transform 400ms, background-color 400ms;
}

.menu {
  display: inline-block;
  flex-direction: column;
  position: relative;
  text-decoration-line: none;
  background-color: $menu-color;
  width: 100%;
  height: 100%;
  margin-left: -8px;
  margin-top: -27px;
  overflow: auto;
  text-align: center;
  top: 0;
  padding-top: 10%;
  list-style: none;
} 

.topnav {
  background-color: $p-header-color;
  display: flex;
  align-items: center;
  width: 100%;
}

.topnav_link {
  color: $menu-color;
  padding: 12px;
  text-decoration: none;
}

/* hide responsive menu */
#topnav_hamburger_icon,
#topnav_responsive_menu {
  display: none;
}

@media only screen and (max-width: 768px) {
  /* hide classic menu */
  #topnav_menu {
    display: none;
  }

  /* position home link at left and hamburger at right */
  #home_link {
    flex-grow: 1;
  }

  /* disable horizontal scrolling  */
  #root {
    position: relative;
    overflow-x: hidden;
  }

  /* show responsive menu and position at the right of the screen */
  #topnav_responsive_menu {
    display: block;
    position: absolute;
    margin: 0;
    right: 0;
    top: 0;
    width: 100vw;
    height: 100vh;

    z-index: 99;

    transform-origin: 0% 0%;
    transform: translate(200%, 0);

    transition: transform 0.5s cubic-bezier(0.77, 0.2, 0.05, 1);
  }

  #topnav_responsive_menu ul {
    display: flex;
    flex-direction: column;

    position: absolute;
    margin: 0;
    right: 0;
    top: 0;

    min-width: 50vw;
    height: 100vh;
    padding: 56px 0 0;

    text-align: center;

    background: $menu-color;
    list-style-type: none;
    -webkit-font-smoothing: antialiased;
  }

  #topnav_responsive_menu li {
    padding: 12px 24px;
  }

  #topnav_responsive_menu a {
    white-space: nowrap;
    color: #333;
    text-decoration: none;
  }

  /* And let's slide it in from the right */
  #topnav_responsive_menu.open {
    transform: none;
    position: fixed;
  }

  /* ******************** HAMBURGER ICON ******************** */
  /* define size and position of the hamburger link */
  #topnav_hamburger_icon {
    display: block;
    position: relative;
    margin: 16px;
    width: 33px;
    height: 28px;

    z-index: 100;

    -webkit-user-select: none;
    user-select: none;
    cursor: pointer;
  }

  /* define the style (size, color, position, animation, ...) of the 3 spans */
  #topnav_hamburger_icon span {
    display: block;
    position: absolute;
    height: 4px;
    width: 100%;
    margin-bottom: 5px;

    background: white;
    border-radius: 3px;

    z-index: 100;

    opacity: 1;
    left: 0;

    -webkit-transform: rotate(0deg);
    -moz-transform: rotate(0deg);
    -o-transform: rotate(0deg);
    transform: rotate(0deg);
    -webkit-transition: 0.25s ease-in-out;
    -moz-transition: 0.25s ease-in-out;
    -o-transition: 0.25s ease-in-out;
    transition: 0.25s ease-in-out;
  }

  /* set the 3 spans position to look like a hamburger */
  #topnav_hamburger_icon span:nth-child(1) {
    top: 0px;
    -webkit-transform-origin: left top;
    -moz-transform-origin: left top;
    -o-transform-origin: left top;
    transform-origin: left top;
  }
  #topnav_hamburger_icon span:nth-child(2) {
    top: 12px;
    -webkit-transform-origin: left center;
    -moz-transform-origin: left center;
    -o-transform-origin: left center;
    transform-origin: left center;
  }
  #topnav_hamburger_icon span:nth-child(3) {
    top: 24px;
    -webkit-transform-origin: left bottom;
    -moz-transform-origin: left bottom;
    -o-transform-origin: left bottom;
    transform-origin: left bottom;
  }

  /* change color when opening the menu */
  #topnav_hamburger_icon.open span {
    background: #333;
  }

  /* the first span rotates 45° \ */
  #topnav_hamburger_icon.open span:nth-child(1) {
    width: 110%;
    -webkit-transform: rotate(45deg);
    -moz-transform: rotate(45deg);
    -o-transform: rotate(45deg);
    transform: rotate(45deg);
  }

  /* the second span disappears */
  #topnav_hamburger_icon.open span:nth-child(2) {
    width: 0%;
    opacity: 0;
  }

  /* the last span rotates -45° / */
  #topnav_hamburger_icon.open span:nth-child(3) {
    width: 110%;
    -webkit-transform: rotate(-45deg);
    -moz-transform: rotate(-45deg);
    -o-transform: rotate(-45deg);
    transform: rotate(-45deg);
  }
}

HTML #

<header>
  <div id="root">
  <div id="topnav" class="topnav">
    <a id="homelink" class="topnav_link" href="accueil.html"><h1>CECILIA FORNES GUECHI<br>
      DEVELOPPEUSE WEB FULLSTACK</h1></a>

    <nav role="navigation" id="topnav_menu" class ="menu">
        <ul class="list-unstyled">
          <li><a class="topnav_link" href="accueil.html">Accueil</a></li>
          <li><a class="topnav_link" href="experiences.html">Expériences</a></li>
          <li><a class="topnav_link" href="benevolat.html">Bénévolats</a></li>
          <li><a class="topnav_link" href="formations.html">Formations<a></li>
          <li><a class="topnav_link" href="certif.html">Certifications</a></li>
          <li><a class="topnav_link" href="competences.html">Compétences</a></li>
          <li><a class="topnav_link" href="loisirs.html">Loisirs</a></li>
          <li><a class="topnav_link" href="contact.html">Contact</a></li>
        </ul>
    </nav>

    <a id="topnav_hamburger_icon" href="javascript:void(0);" onclick="showResponsiveMenu()">
      <!-- Some spans to act as a hamburger -->
      <span></span>
      <span></span>
      <span></span>
    </a>

    <nav role="navigation" id="topnav_responsive_menu">
      <ul class="list-unstyled">
        <li><a href="accueil.html">Accueil</a></li>
        <li><a href="experiences.html">Expériences</a></li>
        <li><a href="benevolat.html">Bénévolats</a></li>
        <li><a href="formations.html">Formations<a></li>
        <li><a href="certif.html">Certifications</a></li>
        <li><a href="competences.html">Compétences</a></li>
        <li><a href="loisirs.html">Loisirs</a></li>
        <li><a href="contact.html">Contact</a></li>
      </ul>
    </nav>

  </div>
  </div>
</header>

问题定位与修复方案 #

1. 修正HTML标签与CSS选择器不匹配问题 #

• CSS媒体查询中使用#home_link，但HTML中对应元素ID为homelink（缺少下划线），需统一二者：要么修改HTML为<a id="home_link"，要么修改CSS为#homelink。
• HTML中两处formations.html的链接标签未闭合（<a>未写</a>），修正为：

  <li><a class="topnav_link" href="formations.html">Formations</a></li>
  

2. 强制刷新浏览器缓存 #

服务器端可能缓存了旧版CSS，导致媒体查询规则未生效。按Ctrl+Shift+R（Windows/Linux）或Cmd+Shift+R（Mac）强制刷新页面，加载最新资源。

3. 确认Sass编译结果 #

代码中使用Sass变量，需确保已编译为普通CSS后再上传服务器：

• 检查编译后的CSS文件是否完整包含媒体查询中的#topnav_menu { display: none; }规则。
• 若未编译，浏览器无法识别Sass变量，可能导致样式解析异常。

4. 增强选择器优先级（可选） #

若媒体查询的隐藏规则因优先级被覆盖，可增强选择器权重：

@media only screen and (max-width: 768px) {
  #topnav_menu.menu {
    display: none !important;
  }
}

内容的提问来源于stack exchange，提问作者Kayliyah