我想要做的是当用户到达网站的下一部分时,将菜单的背景从透明淡化为浅灰色.我已经搜索了一个脚本的高低,并在这里尝试了多个,但似乎没有任何工作.

任何帮助将不胜感激.

谢谢

HTML

    
        
        
        
    

    

    
        
        

            

                
            
            
        
        

        

        
            

            

                
I'm Trisha, a web designer & developer from Illinois.
                
I believe every single detail matters. My goal is to perfect the web one pixel at a time, and provide solutions through thoughtful ideas that translate into designs that last.
            

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CSS

    * {
  margin: 0;
  padding: 0;
}
html, body {
    height: 100%;
-webkit-font-smoothing: antialiased;

}
body {
  background: url(images/home-bg.jpg) no-repeat center center fixed;
  background-size:cover;
    color: #fff;
    font: 300 1em "Open Sans", Helvetica, Arial, sans-serif;
    display: table;
    margin: 0 auto;
}

/*----- NAVIGATION -----*/
#logo {
    position: absolute;
    top: 20px;
    left: 20px;
}
.header {
    display: block;
    position: fixed;
    right: 0;
    left: 0;
    margin: 0;
    width: 100%;
    padding: 30px;
    background-color:transparent;
    box-sizing: border-box;
}
.header.scrolling {
    background: #ccc;
}
#logo img {
    width: 75%;
}
nav input {
  display: none;
}
nav label {
  position: absolute;
  top: 50px;
  right: 10px;
  top: 10px;
  z-index: 999;
  cursor: pointer;
}
nav label strong {
  padding: 0 10px;
  width: 40px;
  height: 40px;
  line-height: 40px!important;
  font: 600 1em "Open Sans", helvetica, sans-serif;
  color: #fff;
  text-transform: uppercase;
  position: absolute;
  right: 40px;
  top: 0px;
  transition: color 250ms ease;
  -webkit-transition: color 250ms ease;
}
nav label b {
  width: 40px;
  height: 40px;
  display: block;
  position: relative;
  right: 0;
  top: 0;
  cursor: pointer;
  transition: background 500ms ease;
  -webkit-transition: background 500ms ease;
}
nav label b i {
  display: block;
  background: #fff;
  width: 24px;
  height: 4px;
  position: absolute;
  left: 8px;
  top: 11px;

  transform-origin: 20px 4px;
  -webkit-transform-origin: 20px 4px;
  transition: transform 500ms ease, opacity 500ms ease;
  -webkit-transition: transform 500ms ease, opacity 500ms ease;
}
nav label b i:nth-child(2) {
  top: 18px;
}
nav label b i:nth-child(3) {
  transform-origin: 26px 4px;
  -webkit-transform-origin: 26px 4px;
  top: 25px;
}
nav menu {
  background: none;
  width: 150px;
  height: 50%;
  opacity: 0;
  transition: opacity 500ms ease;
  -webkit-transition: opacity 500ms ease;
  position: absolute;
  z-index: 998;
  top: 0;
  right: 0;
}
nav menu li {
  margin: 0;
  list-style: none;
  width: 100%;
}
nav menu li:first-child {
  margin-top: 60px;
}
nav menu li:first-child a {
  border-top: rgba(255, 255, 255, 0.2) 1px solid;
}
nav menu li a {
  padding: 20px;
  font: 100 1em "Open Sans", helvetica, sans-serif;
  text-transform: uppercase;
  text-decoration: none;
  text-align: right;
  color: #fff;
  display: block;
}
nav menu li a:hover {
  background: rgba(0, 0, 0, 0.1);
}
nav #nav:checked ~ label strong {
  color: rgba(255, 255, 255, 0.25);
}
nav #nav:checked ~ label b {

}
nav #nav:checked ~ label b i:nth-child(1) {
  transform: rotate(45deg) translate(6px, 11px);
  -webkit-transform: rotate(45deg) translate(6px, 11px);
  transition: all 500ms ease;
  -webkit-transition: all 500ms ease;
}
nav #nav:checked ~ label b i:nth-child(2) {
  opacity: 0;
}
nav #nav:checked ~ label b i:nth-child(3) {
  transform: rotate(-45deg) translate(10px, -14px);
  -webkit-transform: rotate(-45deg) translate(10px, -14px);
    transition: all 500ms ease;
  -webkit-transition: all 500ms ease;
}
nav #nav:checked ~ menu {
  opacity: 1;
}

/*------------------------*/

#container-1 {
    width: 100%;
    height: 100%;
    display: table-cell;
    vertical-align: baseline;
}
.hero {
  margin: auto;
  height: 100%;
  width: 65%;
  padding: 20% 0 0;
}
.hero h1 {
    font-size: 3em;
    font-weight: 300;
    text-align: center;
    color: #ddd;
}
.hero p {
    color: #ddd;
    font-size: 1.5em;
    font-weight: 300;
    text-align: center;
    margin-top: 20px;
    padding-top: 20px;
    border-top: 1px solid rgba(255,255,255,0.2);
}
.next {
    margin: 80px auto;
    width: 150px;
    height: auto;
    border: 2px solid rgba(255,255,255,0.2);
        transition: background 500ms ease;
    -webkit-transition: background 500ms ease;
    text-align: center;
}
.next:hover {
    background: rgba(255,255,255,0.5);
    border: 2px solid rgba(255,255,255,0.0);
    transition: background 500ms ease;
    -webkit-transition: background 500ms ease;
}
.next a {
    text-align: center;
    line-height: 3em;
    text-transform: uppercase;
    letter-spacing: 0.15em;
    color: #fff;
    text-decoration: none;
}
.about {
    background: #fff;   
    width: 100%;
    height: 100%;
}
.about h1 {
    font-size: 3em;
    font-weight: 300;
    text-align: left;
    color: #777;
}
.about p {
    color: #777;
    font-size: 1.5em;
    font-weight: 300;
    text-align: left;
    margin-top: 20px;
    padding: 20px;
    border-top: 1px solid rgba(255,255,255,0.2);
}

/*----- MEDIA QUERIES -----*/
@media only screen and (max-width: 480px) {
    .hero {
        width: 80%;
        margin-top: 20%;
    }
}
@media only screen and (max-width: 768px) {
    .hero {
        width: 80%;
    }
}

Justin.. 10

这是如何在某些滚动位置(基本方式)上向元素添加类的小提琴.显然,你可以从颜色调整到不透明度或任何东西.请注意这需要 jquery.

但是,你无法完成这项工作的原因是因为CSS的设置方式.你的内容中与位置你的头的fixed,而不是.header本身具有应当具有的元素position: fixed.里面的内容不应该修复.