freeCodeCamp/guide/english/css/dropdowns/index.md

---
title: Dropdowns
---

## Dropdowns

Dropdowns are used in CSS to hide a predefined list within a button.

Examples:

```html
<div class="dropdown">
  <button class="dropbtn">Name</button>
  <div class="dropdownContent">
    <a href="#">One</a>
    <a href="#">Two</a>
    <a href="#">Three</a>
  </div>
</div>
```
Then you should customise the classes in css

```css
.dropdown {
  position: relative;
  display: inline-block;
}

.dropbtn {
  background-color: red;
  padding: 10px;
}

.dropdown-content {
  display: none;
  position: absolute;
}

.dropdown:hover .dropdown-content {
  display:block;
}
```

You need the separate div classes to create the button, and another div to separate the list of what the button contains.

#### An Example

```html
<div id="container">
  
        <div id="myNav1" class="overlay">
  
            <div class="overlay-content" id="myNav1-content">
  
                <div>
                    <a href="#" id="list1_obj1" class="list1" >Content 1</a>
                </div>
                <div>
                    <a href="#" id="list1_obj2" class="list1" >Content 2</a>
                </div>
  
            </div>
  
         </div>
  
         <div id="myNav2" class="overlay">
  
             <a href="javascript:void(10)" class="closebtn" onclick="closeNav()">&times</a>
            <div class="overlay-content" id="myNav2-content">
  
                <div>
                    <a href="#" id="list2_obj1" class="list2" >Content 3</a>
                </div>
                <div>
                   <a href="#" id="list2_obj2" class="list2" >Content 4</a>
                </div>
                <div>
                  <a href="#" id="list2_obj3" class="list2" >Content 5</a>
                </div>
  
            </div>
  
         </div>
  
 </div>
```

```css
#myNav1 {
    height: 0;
    width: 50%;
    position: fixed;
    z-index: 6;
    top: 0;
    left: 0;
    background-color: #ffff;
    overflow: hidden;
    transition: 0.3s;
    opacity: 0.85;
}

#myNav2 {
    height: 0;
    width: 50%;
    position: fixed;
    z-index: 6;
    bottom: 0;
    right: 0;
    background-color: #ffff;
    overflow: hidden;
    transition: 0.3s;
    opacity: 0.85;
}

.overlay-content {
    position: relative;
    width: 100%;
    text-align: center;
    margin-top: 30px;
}

#myNav1-content{
    top: 12%;
    left: 5%;
    display: none;
}

#myNav2-content{
    top: 12%;
    right: 10%;
    display: none;   
}
```



#### More Information:
<!-- Please add any articles you think might be helpful to read before writing the article -->
* W3 School Dropdown Hover Button: <a href="https://www.w3schools.com/howto/howto_css_dropdown.asp">Link to W3 School</a>
* W3 School Dropdowns: <a href="https://www.w3schools.com/css/css_dropdowns.asp">Link to W3 School</a>