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HTML
CSS
Result

<!doctype html>
<html>

  <head>
    <title>CSS Project1</title>

  </head>

  <body>
    <nav>
      <ul>
        <li class="dropdown">
          <div class="dropdown-menu">Menu1</div>
          <div class="dropdown-content">
            <a href="#">Menu1-1</a>
            <a href="#">Menu1-2</a>
            <a href="#">Menu1-3</a>
            <a href="#">Menu1-4</a>
          </div>
        </li>
        <li class="dropdown">
          <div class="dropdown-menu">Menu2</div>
          <div class="dropdown-content">
            <a href="#">Menu2-1</a>
            <a href="#">Menu2-2</a>
            <a href="#">Menu2-3</a>
            <a href="#">Menu2-4</a>
          </div>
        </li>
        <li class="dropdown">
          <div class="dropdown-menu">Menu3</div>
          <div class="dropdown-content">
            <a href="#">Menu3-1</a>
            <a href="#">Menu3-2</a>
            <a href="#">Menu3-3</a>
            <a href="#">Menu3-4</a>
          </div>
        </li>
        <li class="dropdown">
          <div class="dropdown-menu">Menu4</div>
        </li>
        <li class="home"><a href="#">Home</a></li>
      </ul>
    </nav>
  </body>

</html>

body {
  margin-top: 30px;
}

nav ul {
  width: 100%;
  background-color: rgba(44, 42, 39, 0.983);
  list-style-type: none;
  /* 마진 패딩 지정하지 않으면 브라우저 기본 스타일을 따라 설정되므로 오버라이딩 필요 */
  margin: 0;
  padding: 0;
}

/* li 는 블록요소인데 inline-block 으로 인라인속성 부여해서 나란히 배치 */

nav ul li {
  display: inline-block;
}

.home {
  background-color: darkorange;
  width: 100px;
  text-align: center;
  font-weight: bold;
  float: right;
}

.home a {
  display: block;
  text-decoration: none;
  color: white;
  padding: 16px 16px;
}

.dropdown {
  position: relative;
}

.dropdown-menu {
  /*background-color: darkorange; */
  color: white;
  padding: 16px;
  font-size: 16px;
  cursor: pointer;
}

.dropdown-content {
  display: none;
  position: absolute;
  background-color: #f9f9f9;
  min-width: 160px;
  box-shadow: 0px 8px 16px 0px rgba(0, 0, 0, 0.2);
}

.dropdown-content a {
  color: black;
  padding: 12px 16px;
  text-decoration: none;
  display: block;
}

/* dropdown-menu 에는 hover 적용이 안됨 */

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

.dropdown-content a:hover {
  background-color: #f1f1f1
}

.dropdown-menu:hover:not(.home) {
  background-color: darkorange;
  color: white;
}