Logo in middle of nav bar without bootstrap

Question

I have a header that I would like to put a logo in the middle of. I don't want to use bootstrap unless there is no other choice. The logo appears to show in the centre of the navigation bar as I would like, however, the links do not go around it properly. Here is an example of what I want the navbar to look like in terms of positioning: ibb.co/zsGG9FY

#firstpage {
  width: 100%;
  height: 100%;
}

#firstpage ul {
  list-style-type: none;
  margin: 0;
  padding: 0;
  overflow: hidden;
  background-color: black;
  position: -webkit-sticky;
  /* Safari */
  position: sticky;
  top: 0;
}

#firstpage li {
  float: left;
}

#firstpage li a {
  display: block;
  color: white;
  text-align: center;
  padding: 33px 19px;
  text-decoration: none;
  font-family: Futura;
  font-size: 11px;
}

#firstpage li a:hover {
  color: #00CFFF;
}

#firstpage .active {
  color: #00CFFF;
}

#firstpage .midlogo {
  position: absolute;
  top: 50%;
  left: 50%;
  transform: translate(-50%, -50%);
}

#firstpage .midlogo img {
  width: 100%;
  height: 100%;
  background-color: white;

<section id="firstpage">
  <ul>
    <li><a class="active" href="#firstpage">HOME</a></li>
    <li><a href="#how-works">HOW IT WORKS</a></li>
    <li><a href="#why-us">WHY CHOOSE US</a></li>
    <li class="midlogo">
      <a href="#firstpage"><img src="logo.png"></a>
    </li>
    <li><a href="#gallery">GALLERY</a></li>
    <li><a href="#services">SERVICES</a></li>
    <li><a href="#contact">CONTACT US</a></li>
  </ul>
</section>

Answer 1

I've removed the classes containing float: left for li items and position: absolute for .midlogo item respectively.

All you need is flex property inside ul item to adjust its 1 dimensional layout.

#firstpage {
  width: 100%;
  height: 100%;
}

#firstpage ul {
  list-style-type: none;
  margin: 0;
  padding: 0;
  overflow: hidden;
  background-color: black;
  position: -webkit-sticky;
  /* Safari */
  position: sticky;
  top: 0;

  /************ ADD FLEX DISPLAY ************/
  display: flex;
  flex-flow: row nowrap;
  justify-content: space-around;
}


#firstpage li a {
  display: block;
  color: white;
  text-align: center;
  padding: 33px 19px;
  text-decoration: none;
  font-family: Futura;
  font-size: 11px;
}

#firstpage li a:hover {
  color: #00CFFF;
}

#firstpage .active {
  color: #00CFFF;
}


#firstpage .midlogo img {
  width: 100%;
  height: 100%;
  background-color: white;
}

<section id="firstpage">
  <ul>
    <li><a class="active" href="#firstpage">HOME</a></li>
    <li><a href="#how-works">HOW IT WORKS</a></li>
    <li><a href="#why-us">WHY CHOOSE US</a></li>
    <li class="midlogo">
      <a href="#firstpage"><img src="logo.png"></a>
    </li>
    <li><a href="#gallery">GALLERY</a></li>
    <li><a href="#services">SERVICES</a></li>
    <li><a href="#contact">CONTACT US</a></li>
  </ul>
</section>

You should read about the flex property- https://developer.mozilla.org/en-US/docs/Web/CSS/flex

Answer 2

My solution uses Flexbox. I've replaced the image with an element with a dashed border so that it's obvious where it is. I've also but a pink background behind each link to show that they are indeed all the same width.

Each normal link has a width of 100% to force them to take up all available space. The logo has flex-shrink:0 so that it retains it's given size.

#firstpage ul {
  list-style-type: none;
  display: flex;
  align-items: center;
  justify-content: space-between;
  margin: 0;
  padding: 0;
  overflow: hidden;
  background-color: black;
  position: -webkit-sticky;
  /* Safari */
  position: sticky;
  top: 0;
}

#firstpage li {
  width: 100%;
}
#firstpage li:nth-child(odd) {
  background: pink;
}

#firstpage li a {
  display: block;
  text-align: center;
  color: white;
  padding: 33px 19px;
  text-decoration: none;
  font-family: Futura;
  font-size: 11px;
}

#firstpage li a:hover {
  color: #00CFFF;
}

#firstpage .active {
  color: #00CFFF;
}

#firstpage .midlogo {
  border: white dashed 3px;
  width: 50px;
  flex-shrink: 0;
  height: 50px;
}

<section id="firstpage">
  <ul>
    <li><a class="active" href="#firstpage">HOME</a></li>
    <li><a href="#how-works">HOW IT WORKS</a></li>
    <li><a href="#why-us">WHY CHOOSE US</a></li>
    <li class="midlogo">
      <a href="#firstpage"></a>
    </li>
    <li><a href="#gallery">GALLERY</a></li>
    <li><a href="#services">SERVICES</a></li>
    <li><a href="#contact">CONTACT US</a></li>
  </ul>
</section>

Answer 3

You have set float: left on <li> tag so it keeps on left position. This should be removed.

And using display: flex layout on ul tag, you can align all items on center.

Attached snippet shows what you need.

#firstpage {
  width: 100%;
  height: 100%;
  display: block;
  margin: 0 auto;
}

#firstpage ul {
  display: flex;
  justify-content: center;
  align-items: center;
  
  list-style-type: none;
  margin: 0;
  padding: 0;
  overflow: hidden;
  background-color: black;
  position: -webkit-sticky;
  /* Safari */
  position: sticky;
  top: 0;
}

#firstpage li a {
  display: block;
  color: white;
  text-align: center;
  padding: 33px 19px;
  text-decoration: none;
  font-family: Futura;
  font-size: 11px;
}

#firstpage li a:hover {
  color: #00CFFF;
}

#firstpage .active {
  color: #00CFFF;
}

#firstpage .midlogo img {
  width: 100%;
  height: 100%;
  background-color: white;
}

<section id="firstpage">
  <ul>
    <li><a class="active" href="#firstpage">HOME</a></li>
    <li><a href="#how-works">HOW IT WORKS</a></li>
    <li><a href="#why-us">WHY CHOOSE US</a></li>
    <li class="midlogo">
      <a href="#firstpage"><img src="logo.png"></a>
    </li>
    <li><a href="#gallery">GALLERY</a></li>
    <li><a href="#services">SERVICES</a></li>
    <li><a href="#contact">CONTACT US</a></li>
  </ul>
</section>