我该如何解决这个导航菜单不透明问题？

Question

我已将代码粘贴到此处：

https://jsfiddle.net/JTBennett/sdydw4L6/ [CSS - 淡入淡出在顶部，导航在底部]

但如果您想在浏览器中查看实际问题，请复制并粘贴以下内容...jsfiddle 以某种方式修复了它。

HTML:

<header class="masthead" style="z-index:9999;  top:30%;">
  <nav>
    <div class="nav-container">
      <div id="fadein-menu-1">
        <input id="slider1" name="slider1" type="checkbox">
        <label class="slide has-child" for="slider1">
          <span class="element">Vi</span>
          <span class="name">V:HCC</span>
        </label>
        <div class="child-menu">
          <a href="#">Option 1</a>
          <a href="#">Option 2</a>
          <a href="#">Option 3</a>
        </div>
      </div>
      <div id="fadein-menu-2">
        <a class="slide" href="#">
          <span class="element">Cd</span>
          <span class="name">Cadence</span>
        </a>
      </div>
      <div id="fadein-menu-3">
        <input id="slider2" name="slider2" type="checkbox">
        <label class="slide has-child" for="slider2">
          <span class="element">Cp</span>
          <span class="name">Capture</span>
        </label>
        <div class="child-menu">
          <a href="#">Option 1</a>
          <a href="#">Option 2</a>
          <a href="#">Option 3</a>
          <a href="#">Option 4</a>
          <a href="#">Option 5</a>
          <a href="#">Option 6</a>
        </div>
      </div>
      <div id="fadein-menu-4">
        <a class="slide" href="#">
          <span class="element">Ea</span>
          <span class="name">V:EA</span>
        </a>
      </div>
</header>

CSS:

/* Delayed Fade-In CSS */

#fadein-menu-1 {
    opacity:0;
    -webkit-animation: fadein 1s ease-in 1s 1 forwards; /* Safari, Chrome and Opera > 12.1 */
       -moz-animation: fadein 1s ease-in 1s 1 forwards; /* Firefox < 16 */
        -ms-animation: fadein 1s ease-in 1s 1 forwards; /* Internet Explorer */
         -o-animation: fadein 1s ease-in 1s 1 forwards; /* Opera < 12.1 */
            animation: fadein 1s ease-in 1s 1 forwards;
}
#fadein-menu-2 {
    opacity:0;
    -webkit-animation: fadein 1s ease-in 1.2s 1 forwards; /* Safari, Chrome and Opera > 12.1 */
       -moz-animation: fadein 1s ease-in 1.2s 1 forwards; /* Firefox < 16 */
        -ms-animation: fadein 1s ease-in 1.2s 1 forwards; /* Internet Explorer */
         -o-animation: fadein 1s ease-in 1.2s 1 forwards; /* Opera < 12.1 */
            animation: fadein 1s ease-in 1.2s 1 forwards;
}
#fadein-menu-3 {
    opacity:0;
    -webkit-animation: fadein 1s ease-in 1.4s 1 forwards; /* Safari, Chrome and Opera > 12.1 */
       -moz-animation: fadein 1s ease-in 1.4s 1 forwards; /* Firefox < 16 */
        -ms-animation: fadein 1s ease-in 1.4s 1 forwards; /* Internet Explorer */
         -o-animation: fadein 1s ease-in 1.4s 1 forwards; /* Opera < 12.1 */
            animation: fadein 1s ease-in 1.4s 1 forwards;
}
#fadein-menu-4 {
    opacity:0;
    -webkit-animation: fadein 1s ease-in 1.6s 1 forwards; /* Safari, Chrome and Opera > 12.1 */
       -moz-animation: fadein 1s ease-in 1.6s 1 forwards; /* Firefox < 16 */
        -ms-animation: fadein 1s ease-in 1.6s 1 forwards; /* Internet Explorer */
         -o-animation: fadein 1s ease-in 1.6s 1 forwards; /* Opera < 12.1 */
            animation: fadein 1s ease-in 1.6s 1 forwards;
}

@keyframes fadein {
{ 0% { opacity:0; } 100% { opacity:1; } }
}

/* Firefox < 16 */
@-moz-keyframes fadein {
    from { opacity: 0; }
    to   { opacity: 1; }
}

/* Safari, Chrome and Opera > 12.1 */
@-webkit-keyframes fadein {
    from { opacity: 0; }
    to   { opacity: 1; }
}

/* Internet Explorer */
@-ms-keyframes fadein {
    from { opacity: 0; }
    to   { opacity: 1; }
}

/* Opera < 12.1 */
@-o-keyframes fadein {
    from { opacity: 0; }
    to   { opacity: 1; }
}





/* Navigation */


a {
  text-decoration: none;
}
.masthead {
  font-family: "Open Sans", sans-serif;
}
nav {
  display: table;
  position: relative;
  table-layout: fixed;
  width: 100%;
}
nav input {
  display: none;
}
nav label {
  margin: 0;
}
nav div.nav-container {
  display: table-row;
}
nav div.nav-container > div {
  display: table-cell;
}
nav div.nav-container > div:nth-of-type(5n+1) .slide, nav div.nav-container > div:nth-of-type(5n+1) a {
  border-color: #186eb5;
}
nav div.nav-container > div:nth-of-type(5n+1) .slide:hover, nav div.nav-container > div:nth-of-type(5n+1) a:hover {
  color: #186eb5;
}
nav div.nav-container > div:nth-of-type(5n+1) .slide ~ .child-menu, nav div.nav-container > div:nth-of-type(5n+1) a ~ .child-menu {
  background-color: #186eb5;
}
nav div.nav-container > div:nth-of-type(5n+1) input:checked ~ label, nav div.nav-container > div:nth-of-type(5n+1) .slide.active ~ label {
  color: #186eb5;
}
nav div.nav-container > div:nth-of-type(5n+2) .slide, nav div.nav-container > div:nth-of-type(5n+2) a {
  border-color: #5aab1e;
}
nav div.nav-container > div:nth-of-type(5n+2) .slide:hover, nav div.nav-container > div:nth-of-type(5n+2) a:hover {
  color: #5aab1e;
}
nav div.nav-container > div:nth-of-type(5n+2) .slide ~ .child-menu, nav div.nav-container > div:nth-of-type(5n+2) a ~ .child-menu {
  background-color: #5aab1e;
}
nav div.nav-container > div:nth-of-type(5n+2) input:checked ~ label, nav div.nav-container > div:nth-of-type(5n+2) .slide.active ~ label {
  color: #5aab1e;
}
nav div.nav-container > div:nth-of-type(5n+3) .slide, nav div.nav-container > div:nth-of-type(5n+3) a {
  border-color: #db0a21;
}
nav div.nav-container > div:nth-of-type(5n+3) .slide:hover, nav div.nav-container > div:nth-of-type(5n+3) a:hover {
  color: #db0a21;
}
nav div.nav-container > div:nth-of-type(5n+3) .slide ~ .child-menu, nav div.nav-container > div:nth-of-type(5n+3) a ~ .child-menu {
  background-color: #db0a21;
}
nav div.nav-container > div:nth-of-type(5n+3) input:checked ~ label, nav div.nav-container > div:nth-of-type(5n+3) .slide.active ~ label {
  color: #db0a21;
}
nav div.nav-container > div:nth-of-type(5n+4) .slide, nav div.nav-container > div:nth-of-type(5n+4) a {
  border-color: #6926b8;
}
nav div.nav-container > div:nth-of-type(5n+4) .slide:hover, nav div.nav-container > div:nth-of-type(5n+4) a:hover {
  color: #6926b8;
}
nav div.nav-container > div:nth-of-type(5n+4) .slide ~ .child-menu, nav div.nav-container > div:nth-of-type(5n+4) a ~ .child-menu {
  background-color: #6926b8;
}
nav div.nav-container > div:nth-of-type(5n+4) input:checked ~ label, nav div.nav-container > div:nth-of-type(5n+4) .slide.active ~ label {
  color: #6926b8;
}
nav div.nav-container > div:nth-of-type(5n+5) .slide, nav div.nav-container > div:nth-of-type(5n+5) a {
  border-color: #FC1DCF;
}
nav div.nav-container > div:nth-of-type(5n+5) .slide:hover, nav div.nav-container > div:nth-of-type(5n+5) a:hover {
  color: #b1028d;
}
nav div.nav-container > div:nth-of-type(5n+5) .slide ~ .child-menu, nav div.nav-container > div:nth-of-type(5n+5) a ~ .child-menu {
  background-color: #fd4fda;
}
nav div.nav-container > div:nth-of-type(5n+5) input:checked ~ label, nav div.nav-container > div:nth-of-type(5n+5) .slide.active ~ label {
  color: #FC1DCF;
}
nav a, nav label {
  -moz-transition-property: color;
  -o-transition-property: color;
  -webkit-transition-property: color;
  transition-property: color;
  -moz-transition-duration: 0.2s;
  -o-transition-duration: 0.2s;
  -webkit-transition-duration: 0.2s;
  transition-duration: 0.2s;
  -moz-transition-timing-function: ease-in;
  -o-transition-timing-function: ease-in;
  -webkit-transition-timing-function: ease-in;
  transition-timing-function: ease-in;
}
nav .slide {
  padding: 10px 10px;
  font-size: 1em;
  display: block;
  color: #393939;
  border-top: 4px solid transparent;
  position: relative;
  -moz-transition-property: border-width, color;
  -o-transition-property: border-width, color;
  -webkit-transition-property: border-width, color;
  transition-property: border-width, color;
  -moz-transition-duration: 0.1s, 0.2s;
  -o-transition-duration: 0.1s, 0.2s;
  -webkit-transition-duration: 0.1s, 0.2s;
  transition-duration: 0.1s, 0.2s;
  -moz-transition-timing-function: ease-in;
  -o-transition-timing-function: ease-in;
  -webkit-transition-timing-function: ease-in;
  transition-timing-function: ease-in;
  -moz-transition-delay: 0.2s, 0s;
  -o-transition-delay: 0.2s, 0s;
  -webkit-transition-delay: 0.2s, 0s;
  transition-delay: 0.2s, 0s;
}
nav .slide .element {
  font-size: 1.25em;
  font-weight: 600;
  font-style: normal;
  display: block;
  line-height: 1;
}
nav .slide .name {
  font-size: 0.6875em;
  position: relative;
}
nav .has-child .name:after {
  content: "";
  width: 10px;
  height: 4px;
  background-image: url("http://www.elemental-shift.com/remote-assets/down-arrow.svg");
  display: block;
  position: absolute;
  bottom: -9px;
  left: 1px;
  background-repeat: no-repeat;
  -moz-transition-property: -moz-transform;
  -o-transition-property: -o-transform;
  -webkit-transition-property: -webkit-transform;
  transition-property: transform;
  -moz-transition-duration: 0.5s;
  -o-transition-duration: 0.5s;
  -webkit-transition-duration: 0.5s;
  transition-duration: 0.5s;
  -moz-transition-timing-function: ease-in;
  -o-transition-timing-function: ease-in;
  -webkit-transition-timing-function: ease-in;
  transition-timing-function: ease-in;
  -moz-transform-origin: 50% 50%;
  -ms-transform-origin: 50% 50%;
  -webkit-transform-origin: 50% 50%;
  transform-origin: 50% 50%;
}
nav .child-menu {
  display: block;
  position: absolute;
  max-height: 0;
  overflow: hidden;
  background-color: #393939;
  width: 100%;
  top: 65px;
  left: 0;
  z-index: 5000;
  -moz-transition-property: max-height;
  -o-transition-property: max-height;
  -webkit-transition-property: max-height;
  transition-property: max-height;
  -moz-transition-duration: 0.5s;
  -o-transition-duration: 0.5s;
  -webkit-transition-duration: 0.5s;
  transition-duration: 0.5s;
  -moz-transition-timing-function: ease-in;
  -o-transition-timing-function: ease-in;
  -webkit-transition-timing-function: ease-in;
  transition-timing-function: ease-in;
}
nav .child-menu a {
  color: white;
  display: inline-block;
  padding: 15px 30px 15px 10px;
  font-size: 0.9375em;
}
nav input:checked ~ .child-menu {
  max-height: 100px;
  -moz-transition-property: max-height;
  -o-transition-property: max-height;
  -webkit-transition-property: max-height;
  transition-property: max-height;
  -moz-transition-duration: 0.5s;
  -o-transition-duration: 0.5s;
  -webkit-transition-duration: 0.5s;
  transition-duration: 0.5s;
  -moz-transition-timing-function: ease-in;
  -o-transition-timing-function: ease-in;
  -webkit-transition-timing-function: ease-in;
  transition-timing-function: ease-in;
}
nav input:checked ~ .has-child .name:after {
  -moz-transform: rotateX(180deg);
  -webkit-transform: rotateX(180deg);
  transform: rotateX(180deg);
}

@media only screen and (min-width: 48.0625em) {
  nav {
    display: block;
    table-layout: auto;
  }
  nav div.nav-container {
    display: block;
  }
  nav div.nav-container > div {
    display: block;
    margin: 5px 0;
  }
  nav div.nav-container > div:hover .slide {
    border-left-width: 55px;
    -moz-transition-delay: 0;
    -o-transition-delay: 0;
    -webkit-transition-delay: 0;
    transition-delay: 0;
  }
  nav .slide {
    display: block;
    width: auto;
    border-left: solid 4px #393939;
    border-top: none;
  }
  nav .slide .element {
    line-height: 1;
  }
  nav .child-menu {
    display: block;
    position: relative;
    top: 0;
    background-color: transparent !important;
    margin-left: 55px;
    width: auto;
    max-height: 0px;
    overflow: hidden;
    border-top: none;
  }
  nav .child-menu a {
    color: #393939;
    display: block;
    padding: 3px 0 3px 10px;
    font-size: 0.8125em;
  }
  nav input:checked ~ div.child-menu {
    max-height: 120px;
  }
  nav input:checked ~ .slide {
    border-width: 55px;
  }
.masthead {
    position: absolute;
    top: 0;
    left: 0;
    width: 150px;
}
}

它实际上在 jsfiddle 中工作得很好，但是当我运行它在我的浏览器中时，默认全尺寸位置（顶部对齐）的子菜单保持 0 不透明度时出现问题。它在 Chrome 和 Safari 中是相同的，并且几乎可以肯定这是不透明度在动画命令后无法自行解决的问题，但它只发生在默认子菜单中似乎很奇怪。如果删除 opacity:0;来自#fadein-menu-1/2/3/4 ID 的行，子菜单再次起作用。

我觉得我只是错过了一件明显的、愚蠢的小东西……但我一辈子都找不到它。非常感谢您的帮助。

Answer 1

问题：

animation: fadein 1s ease-in 1.4s 1 forwards;

您正在尝试淡入具有 opacity:0; 的元素。您的动画运行一次意味着元素淡入，然后元素 return 变为默认样式 (opacity:0;)。所以你看不到那些元素。

解决方案：从默认样式中删除不透明度。

#fadein-menu-1 {
    /* Remove from all the elements */
    //opacity:0;
    -webkit-animation: fadein 1s ease-in 1s 1 forwards; /* Safari, Chrome and Opera > 12.1 */
       -moz-animation: fadein 1s ease-in 1s 1 forwards; /* Firefox < 16 */
        -ms-animation: fadein 1s ease-in 1s 1 forwards; /* Internet Explorer */
         -o-animation: fadein 1s ease-in 1s 1 forwards; /* Opera < 12.1 */
            animation: fadein 1s ease-in 1s 1 forwards;
}

Jsfiddle

我该如何解决这个导航菜单不透明问题？

How can I fix this nav menu opacity issue?

css

animation

opacity

fadein

nav