元素与固定导航栏重叠

Question

我做了一个简单的投资组合网站，顶部有一个固定的导航栏。 向下滚动时，svg图标将出现在导航栏上方，而不是我想要的下方。 同样，带有某些动画的任何元素都会遇到相同的问题。尝试了z-index技巧，但没有用。 这是代码的链接： https://codepen.io/mohammad-sharara/pen/MWeYVvN?editors=1100 HTML代码：

        <!--Welcome part-->
        <nav id="navbar">
            <div><a href="#welcome-section">About</a></div>
            <div><a href="#projects">Work</a></div>
            <div><a href="#contact">Contact</a></div>
        </nav>
        <div id="welcome-section">
            <h1>Hello, I'm Mohammad</h1>
            <h2>A web developer</h2>
        </div>
        <!--Projects Part-->
        <div id="projects">
            <div id="title"><h2>Here are some of my projects</h2></div>
            <div id="projects-container">
                <div class="project-title">
                    <a href="https://codepen.io/mohammad-sharara/full/qBOPmWR"><div class="image-wrapper"><img src="https://raw.githubusercontent.com/msharara1998/freeCodeCamp-files/master/Capture3.JPG" alt=""></div>
                    <h3><span></span> Survey Form</h3></a>
                </div>
                <div class="project-title">
                    <a href="https://codepen.io/mohammad-sharara/full/oNxqEbP"><div class="image-wrapper"><img src="https://raw.githubusercontent.com/msharara1998/freeCodeCamp-files/master/Capture4.JPG" alt=""></div>
                    <h3>Product Landing</h3></a>
                </div>
                <div class="project-title">
                    <a href="https://codepen.io/mohammad-sharara/full/qBdvWdo"><div class="image-wrapper"><img src="https://raw.githubusercontent.com/msharara1998/freeCodeCamp-files/master/Capture1.JPG" alt=""></div>
                    <h3>Tribute Page</h3></a>
                </div>
                <div class="project-title">
                    <a href="https://codepen.io/mohammad-sharara/full/XWdBKQx"><div class="image-wrapper"><img src="https://raw.githubusercontent.com/msharara1998/freeCodeCamp-files/master/Capture2.JPG" alt=""></div>
                    <h3>Technical Documentation</h3></a>
                </div>
                <div class="project-title">
                    <a href="https://codepen.io/mohammad-sharara/full/PozwQNz"><div class="image-wrapper"><img src="https://raw.githubusercontent.com/msharara1998/freeCodeCamp-files/master/Capture5.JPG" alt=""></div>
                    <h3>Colorful Cards</h3></a>
                </div>
                <div class="project-title">
                    <a href="https://codepen.io/mohammad-sharara/full/WNxbMoE"><div class="image-wrapper"><img src="https://raw.githubusercontent.com/msharara1998/freeCodeCamp-files/master/Capture6.JPG" alt=""></div>
                    <h3>Responsive Webpage</h3></a>
                </div>
            </div>
            <div id="button">
                <div><a href="https://codepen.io/mohammad-sharara">Show all <span>&gt;</span> </a></div>
            </div>
        </div>
        <!--Contact Part-->
        <div id="contact">
            <div id="headings">
                <h1>At Your Service!</h1>
                <h2>Are you ready to discuss your order?</h2>
            </div>
            <div id="contact-links">
                <div class="social-media"><a href="https://github.com/msharara1998" target="_blank"><svg xmlns="http://www.w3.org/2000/svg" width="24" height="24" viewBox="0 0 24 24"><path d="M12 0c-6.626 0-12 5.373-12 12 0 5.302 3.438 9.8 8.207 11.387.599.111.793-.261.793-.577v-2.234c-3.338.726-4.033-1.416-4.033-1.416-.546-1.387-1.333-1.756-1.333-1.756-1.089-.745.083-.729.083-.729 1.205.084 1.839 1.237 1.839 1.237 1.07 1.834 2.807 1.304 3.492.997.107-.775.418-1.305.762-1.604-2.665-.305-5.467-1.334-5.467-5.931 0-1.311.469-2.381 1.236-3.221-.124-.303-.535-1.524.117-3.176 0 0 1.008-.322 3.301 1.23.957-.266 1.983-.399 3.003-.404 1.02.005 2.047.138 3.006.404 2.291-1.552 3.297-1.23 3.297-1.23.653 1.653.242 2.874.118 3.176.77.84 1.235 1.911 1.235 3.221 0 4.609-2.807 5.624-5.479 5.921.43.372.823 1.102.823 2.222v3.293c0 .319.192.694.801.576 4.765-1.589 8.199-6.086 8.199-11.386 0-6.627-5.373-12-12-12z"/></svg><span>GitHub</span></a></div>
                <div class="social-media"><a href="https://twitter.com/Mohamma97493188" target="_blank"><svg xmlns="http://www.w3.org/2000/svg" width="24" height="24" viewBox="0 0 24 24"><path d="M12 0c-6.627 0-12 5.373-12 12s5.373 12 12 12 12-5.373 12-12-5.373-12-12-12zm6.066 9.645c.183 4.04-2.83 8.544-8.164 8.544-1.622 0-3.131-.476-4.402-1.291 1.524.18 3.045-.244 4.252-1.189-1.256-.023-2.317-.854-2.684-1.995.451.086.895.061 1.298-.049-1.381-.278-2.335-1.522-2.304-2.853.388.215.83.344 1.301.359-1.279-.855-1.641-2.544-.889-3.835 1.416 1.738 3.533 2.881 5.92 3.001-.419-1.796.944-3.527 2.799-3.527.825 0 1.572.349 2.096.907.654-.128 1.27-.368 1.824-.697-.215.671-.67 1.233-1.263 1.589.581-.07 1.135-.224 1.649-.453-.384.578-.87 1.084-1.433 1.489z"/></svg><span>Twitter</span></a></div>
                <div class="social-media"><a href="mailto:ms198mohammad@gmail.com?subject=Reaching%20Out&body=Hello%20World"><svg xmlns="http://www.w3.org/2000/svg" width="24" height="24" viewBox="0 0 24 24"><path d="M12 .02c-6.627 0-12 5.373-12 12s5.373 12 12 12 12-5.373 12-12-5.373-12-12-12zm6.99 6.98l-6.99 5.666-6.991-5.666h13.981zm.01 10h-14v-8.505l7 5.673 7-5.672v8.504z"/></svg><span>Email</span></a></div>
            </div>
            <div id="portrait">
                <img src="https://raw.githubusercontent.com/msharara1998/freeCodeCamp-files/master/IMG_2713.jpg" alt="Personal Portrait">
            </div>
        </div>
        <!--Footer-->
        <div id="footer">
            <span>Copyright &copy;2020 <br>Created by Mohammad Sharara</span>
        </div>
    </body>

css代码：

  margin: 0;
  padding: 0;
  box-sizing: border-box;
}
body {
  min-height: 100vh;
  font-family: 'Courier New', Courier, monospace;
  letter-spacing: 0.5px;
  overflow-x: hidden;
}
#navbar {
  background:#5e227f;
  position: sticky;
  top: 0;
  height: 110px;
  width: 100vw;
  display: flex;
  justify-content: flex-end;
  align-items: center;
  padding-right: 20px;
}
#navbar a {
  margin: 0 30px;
  padding: 8px;
  text-decoration-line: none;
  font-size: 29px;
  color: #f8b500;
  font-weight: bolder;
}
#navbar div, .social-media {
  position: relative;
  z-index: 0;
  padding: 5px;
}
#navbar div:before,.social-media:before {
  content:'';
  transition: 0.3s;
}
#navbar div:hover:before,.social-media:hover:before {
  position: absolute;
  width: 80%;
  height: 100%;
  top: -1px;
  left: 15px;
  z-index: -1;
  background: #d22780;
  transform: skewX(3deg) skewY(1.5deg);
}
#navbar div:nth-child(2):hover:before {
  transform: skewX(-1deg) skewY(-2deg);
}
#welcome-section {
  background: #f2f4fb;
  height: 100vh;
  width: 100vw;
  z-index: -2;
  display: flex;
  flex-direction: column;
  justify-content: center;
  align-items: center;
}
#welcome-section h1 {
  margin: 20px;
  font-size: 65px;
  font-weight: bold;
}
/*  The typewriting animation is credited to Geoff Graham on
https://css-tricks.com/   */
#welcome-section h2 {
  overflow: hidden;
  border-right: .15em solid #f8b500;
  white-space: nowrap;
  margin: 0 auto;
  font-size: 40px;
  font-weight: 300;
  letter-spacing: .15em;
  animation:
    typing 2s steps(30,end),
    blink-caret .68s step-end infinite;
}
@keyframes typing {
  from { width: 0 }
  to { width: 38%; }
}

@keyframes blink-caret {
  from, to { border-color: transparent }
  50% { border-color: #f8b500; }
}
#projects {
  background: #d22780;
  width: 100%;
  padding-bottom: 20px;
  padding-top: 40px;
}
#projects-container {
  display: flex;
  min-height: 100vh;
  flex-wrap: wrap;
  justify-content: center;
  align-items: center;
}
.image-wrapper {
  height: 30vw;
  width: 40vw;
}
.project-title img {
  height: 100%;
  width: 100%;
  object-fit: cover;
}
.project-title {
  margin: 40px;
  background: #BDBDBD;
}
.project-title h3 {
  text-align: center;
  background: #BDBDBD;
  height: 90px;
  width: 100%;
  padding: 28px;
  font-size: 22px;
  transition: 0.3s;
}
.project-title:hover h3 {
  background: #f2f4fb;
}
a {
text-decoration-line: none;
}
@media (max-width: 1210px) {
  .image-wrapper {
    width: 68vw;
    height: 52vw;
  }
  #welcome-section h1 {
    font-size: 1.9em;
  }
  #welcome-section h2 {
    font-size: 1.5em;
  }
 
  #navbar div a{
    font-size: 1.2em;
  }
  #contact-links {
    flex-direction: column;
  }
  #headings h1 {
    font-size: 1em;
    margin-top: 40px;
  }
  #headings h2 {
    font-size: 10px;
  }
  #title {
    max-width: 100vw;
  }
  .project-title h3 {
    font-size: 1em;
    height: 70px;
  }
  .social-media:nth-child(3):hover:before {
    width: 139px;
    left: 13px;
  }
}
@media (min-width: 1600px) {
  .image-wrapper {
    height: 20vw;
    width: 25vw;
  }
}
#button {
  margin: 50px 0;
}
#button div {
  display: flex;
  align-items: center;
  justify-content: center;
  text-align: center;
  font-size: 24px;
  font-weight: 700;
  background: #BDBDBD;
  width: 230px;
  height: 40px;
  margin: 0 auto;
  transition: 0.6s  
}
#button div:hover {
  background: #f8b500;
}
#button span {
  color: initial;
  transition: 0.6s;
}
#button:hover span{
   color: #5e227f;
}

#projects >h2{
  padding: 50px;
  font-size: 30px;
  cursor: default;
  background: #f8b500;
}
#title {
  text-align: center;
  background: #f8b500;
  width: 470px;
  margin: auto;
  padding: 18px;
}
#contact {
  display: flex;
  min-height: 89vh;
  flex-direction: column;
  justify-content: space-evenly;
  align-items: center;
  text-align: center;
  background: #f8b500;
  width: 100%;
}
#contact div {
  margin: 30px;
}
#headings h1{
  font-size: 25px;
}
#headings h2 {
  font-size: 20px;
  margin: 40px;
}
#contact-links {
  display: flex;
}
.social-media {
  margin: 0 100px;
  font-size: 1.8em;
  font-weight: 600;
  display: flex;
  justify-content: center;
}
.social-media:hover:before {
  width: 138px;
  left: -5px;
}
.social-media:first-child:hover:before {
  width: 139px;
  transform: skewX(-2deg) skewY(-2deg);
  }
.social-media:nth-child(3):hover:before {
width: 110px;
transform: skewX(-1deg) skewY(-2deg);
}
#portrait img {
height: 120px;
width: 120px;
border-radius: 50%;
border: 4px solid #212121;
}
#footer {
  display: flex;
  justify-content: flex-end;
  align-items: center;
  height: 140px;
  padding: 20px 60px;
  background: #212121;
  color: #f8b500;
  font-size: 1rem;
  font-weight: 600;
}
svg {
  height: 40px;
  width: 40px;
  margin: 10px;
  vertical-align: middle;
  border-radius: 50%;
}
.social-media span {
  display: block;
  color: #212121;
}
a:visited {
  color: initial;
}
#projects a {
  color: inherit;
}
@media (max-width: 450px) {
 #navbar {
    font-size: 0.7em;
    height: 140px;
    flex-direction: column;
    justify-content: space-evenly;
  }
  #welcome-section h1 {
    margin-top: 100px;
    font-size: 1.4em;
  }
  #welcome-section h2 {
    font-size: 1.1em;
  }
  #footer {
    font-size: 15px;
  }
}
@media (min-width: 700px) {
    @keyframes typing {
  from { width: 0 }
  to { width: 35vw; }
  }
}```

Answer 1

在 #navbar 中添加z-index:1000。工作Pen！

Answer 2

将导航栏的z索引设为1000，将svg的z索引设为-100。那应该做。