如何使手机菜单响应？

Question

I used W3Schools to code a sidenav overlay menu https://www.w3schools.com/howto/howto_js_sidenav.asp with an accordion https://www.w3schools.com/howto/howto_js_accordion.asp . I am trying to figure out how to make it responsive, but I am having no luck.

I have tried using #menu to fix it but the entire menu disappears. I do not know if it is because I am not using ul or li for my links or not.

<header>
   <div id="mySidenav" class="sidenav">
      <a href="javascript:void(0)" class="closebtn" onclick="closeNav()">&times;</a>
      <a href="index.html">Home</a>
      <a class="accordion" href="#">Design &#9663;</a>
      <div class="panel">
         <a href="mobile.html">Mobile</a>
         <a href="#">Web</a>
      </div>
      <a href="photography.html">Photography</a>
      <a href="branding.html">Branding</a>
      <a href="about.html">About | Contact</a>
   </div>
   <span class="opening" onclick="openNav()"><i class="fas fa-stream"></i></span>
</header>

.sidenav {
    position: fixed;
    width: 0;
    height: 100%;
    top: 0;
    left: 0;
    padding-top: 4rem;
    z-index: 1;
    transition: 0.5s;
    overflow-x: hidden;
    background-color: ghostwhite;
    float: left;
}

.sidenav a {
    display: block;
    padding: 10px 10px 10px 32px;
    transition: 0.3s;
    font-size: 1rem;
    font-family: mr-eaves-xl-modern,sans-serif;
    font-weight: 300;
    font-style: normal;
    letter-spacing: 1.5px;
    text-decoration: none;
    text-align: left;
    color: #504E4E;
}

.sidenav a:hover {
    font-style: italic;
}

.opening {
    position: absolute;
    top: 1.5rem;
    left: 5%;
    font-size: 1.3rem;
    color: #504E4E;
    float: left;
}

.sidenav .closebtn {
    position: absolute;
    top: 0;
    right: 5%;
    margin-left: 20%;
    float: left;
}

.accordion {
    width: 100%;
    padding: 18px;
    border: none;
    outline: none;
    transition: 0.4s;
    font-size: 1rem;
    text-align: left;
    color: #504E4E;
}

.active .accordion:hover{
    font-style: italic;
}

.panel {
    max-height: 0;
    padding: 0 18px;
    overflow: hidden;
    transition: max-height 0.2s ease-out;
    background-color: ghostwhite;
    font-size: 1rem;
    font-family: mr-eaves-xl-modern,sans-serif;
    font-weight: 300;
    font-style: normal;
    letter-spacing: 1.5px;
    text-decoration: none;
    color: #504E4E;
}

I would like for it to be a horizontal menu when scaled to desktop.

Answer 1

Using ul and li shouldn't have an effect.

Use media queries to apply a new style that overwrites your current style when your screen is at a certain size.

To target all screens that have a width greater than or equal to 1024 pixels use @media ( min-width: 1024px ) . To target screens with width less than or equal to 1024 pixels use @media ( max-width: 1024px ) .

One reason your menu isn't displaying is because you've set the width to 0 in the .sidenav selector. Remove that line. To make the menu display full width on desktop you might add the following code to your CSS file:

@media ( min-width: 1000px ) {
    .sidenav {
        width: 100%;
        height: auto;
        display: flex;
        justify-content: flex-end;
    }
    .sidenav > a {
        width: auto;
    }
}

This will not display the accordion well; you may need to restructure your HTML. However this should get you started with media queries and using different styles at different screen sizes.