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HTML

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Insecure Resource

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CSS

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CSS Base

About CSS Base

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JavaScript

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JavaScript preprocessors can help make authoring JavaScript easier and more convenient.

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Babel includes JSX processing.

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HTML 

              
                <div style="text-align: center; margin-top: 2rem;">
  <h2>#4: Toggle with JavaScript</h2>
  <p>Click on the button and toggle the dropdown menu</p>
</div>

<div class="dropdown">
  <button class="dropdown-btn" aria-label="menu button" aria-haspopup="menu" aria-expanded="false" aria-controls="dropdown-menu">
    <span>Framework</span>
    <span class="arrow"></span>
  </button>
  <ul class="dropdown-content" role="menu" id="dropdown-menu">
    <li style="--delay: 1;"><a href="#">React</a></li>
    <li style="--delay: 2;"><a href="#">Angular</a></li>
    <li style="--delay: 3;"><a href="#">Vue</a></li>
    <li style="--delay: 4;"><a href="#">Svelte</a></li>
  </ul>
</div>
!

CSS 

              
                /* Dropdown styles */

.dropdown {
  max-width: 13em;
  margin: 80px auto 0;
  position: relative;
  width: 100%;
}

.dropdown-btn {
  background: #1d1f24;
  font-size: 18px;
  width: 100%;
  border: none;
  color: #fff;
  display: flex;
  justify-content: space-between;
  align-items: center;
  padding: 0.7em 0.5em;
  border-radius: 0.5em;
  cursor: pointer;
}

.arrow {
  border-left: 5px solid transparent;
  border-right: 5px solid transparent;
  border-top: 6px solid #fff;
  transition: transform ease-in-out 0.3s;
}

.dropdown-content {
  list-style: none;
  position: absolute;
  top: 3.2em;
  width: 100%;
  visibility: hidden;
  overflow: hidden;
}

.dropdown-content li {
  background: #2f3238;
  border-radius: 0.5em;
  position: relative;
  left: 100%;
  transition: 0.5s;
  transition-delay: calc(60ms * var(--delay));
}

.dropdown-content.menu-open li {
  left: 0;
}

.dropdown-content.menu-open {
  visibility: visible;
}

.arrow.arrow-rotate {
  transform: rotate(180deg);
}

.dropdown-content li:hover {
  background: #1d1f24;
}

.dropdown-content li a {
  display: block;
  padding: 0.7em 0.5em;
  color: #fff;
  margin: 0.1em 0;
  text-decoration: none;
}

/* base styles */
* {
  box-sizing: border-box;
  margin: 0;
  padding: 0;
}
body {
  font-family: "Segoe UI", sans-serif;
  color: #333;
/*   background: #cecece; */
}
!

JS 

              
                const dropdownBtn = document.querySelector(".dropdown-btn");
const dropdownCaret = document.querySelector(".arrow");
const dropdownContent = document.querySelector(".dropdown-content");

// add click event to dropdown button
dropdownBtn.addEventListener("click", () => {
  // add rotate to caret element
  dropdownCaret.classList.toggle("arrow-rotate");
  // add open styles to menu element
  dropdownContent.classList.toggle("menu-open");
  dropdownBtn.setAttribute(
    "aria-expanded",
    dropdownBtn.getAttribute("aria-expanded") === "true" ? "false" : "true"
  );
});
!
999px

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