Tạo Menu ngang thả xuống trong Blogspot

   Trong bố cục Blogspot thêm tiện ích HTML/Javascrip, sau đó dán đoạn code bên dưới vào:

<link rel="stylesheet" href="https://cdnjs.cloudflare.com/ajax/libs/font-awesome/4.7.0/css/font-awesome.min.css" />
<style>
.navbar-left {
  float: left;
  width:100%;
  overflow: hidden;
  background-color: #3e8e41;
  z-index: 6;

}
.navbar-right{
  float: right;
  width: 5%;
 overflow: hidden;
  background-color: #3e8e41;
  z-index: 6;
}
.navbar-left a {
  float: left;
  font-size: 16px;
  color: white;
  text-align: center;
  padding: 14px 16px;
  text-decoration: none;
}

.dropdown {
  float: left;
  overflow: hidden;
z-index: 6;
}

.dropdown .dropbtn {
  font-size: 16px;  
  border: none;
  outline: none;
  color: white;
  padding: 14px 16px;
  background-color: inherit;
  font-family: inherit;
  margin: 0;
z-index: 6;
}

.navbar1 a:hover, .dropdown:hover .dropbtn {
  background-color: #4CAF50;
z-index: 6;
}

.dropdown-content {
  display: none;
  position: absolute;
  background-color: #f9f9f9;
  min-width: 200px;
  box-shadow: 0px 8px 16px 0px rgba(0,0,0,0.2);
  z-index: 6;
}

.dropdown-content a {
  float: none;
  color: #0000CD;
  padding: 12px 16px;
  text-decoration: none;
  display: block;
  text-align: left;
z-index: 6;
}

.dropdown-content a:hover {
  background-color: #89d08a;
 color: #8B0000;
z-index: 6;
}

.dropdown:hover .dropdown-content {
  display: block;
z-index: 6;
}
</style>

<div class="navbar-left">


<div class="dropdown">
    <button class="dropbtn" style='padding: 0px;'>
 <a href="https://www.vnkha.com/">🏠</a>
    </button>
    </div> 

 
<div class="dropdown">
    <button class="dropbtn">Lập trình &#8794;</button>
       <div class="dropdown-content">
           <a href="https://www.vnkha.com/search/label/Lap-trinh-C">Lập trình C</a>
           <a href="https://www.vnkha.com/search/label/Cpp">Lập trình C++</a>
           <a href="https://www.vnkha.com/search/label/Cau-truc-du-lieu-va-giai-thuat">Cấu trúc DL & GT</a>
       </div>
    </div> 

  <div class="dropdown">
    <button class="dropbtn">Website &#8794;
    </button>
             <div class="dropdown-content">
                    <a href="https://www.vnkha.com/search/label/HTML5">HTML5</a>
                    <a href="https://www.vnkha.com/search/label/DreamWeaver">DreamWeaver</a>
                    <a href="https://www.vnkha.com/search/label/CSS">CSS</a>
                    <a href="https://www.vnkha.com/search/label/PHP-MySQL">PHP & MySQL</a>
                    <a href="https://www.vnkha.com/search/label/Blogspot">Blogspot</a>
            </div>        
    </div> 

 <div class="dropdown">
    <button class="dropbtn">Đồ họa &#8794;
    </button>
             <div class="dropdown-content">
                    <a href="https://www.vnkha.com/search/label/Corel">CorelDraw</a>
                    <a href="https://www.vnkha.com/search/label/PhotoShop">PhotoShop</a>
             </div>
    </div> 

<div class="dropdown">
    <button class="dropbtn">Máy tính &#8794;
    </button>
             <div class="dropdown-content">
                    <a href="https://www.vnkha.com/search/label/LRCDvaBT-May-tinh">Lắp ráp CĐ và BT máy tính</a>
                    <a href="https://www.vnkha.com/search/label/Thu-thuat-may-tinh">Thủ thuật máy tính</a>
             </div>
    </div> 

<div class="dropdown">
    <button class="dropbtn">Tin học VP &#8794;
    </button>
             <div class="dropdown-content">
                    <a href="https://www.vnkha.com/search/label/Tin-hoc-co-ban">Tin học cơ bản</a>
                    <a href="https://www.vnkha.com/search/label/Windows">Windows</a>
                    <a href="https://www.vnkha.com/search/label/Word">Word</a>
                    <a href="https://www.vnkha.com/search/label/Excel">Excel</a>
             </div>
    </div> 
 
<div class="dropdown">
    <button class="dropbtn">Mục khác &#8794;
    </button>
             <div class="dropdown-content">
                   <a href="https://www.vnkha.com/search/label/Blog">Blog</a>
                    <a href="https://www.vnkha.com/search/label/Online-Code">Online Code</a>
                    <a href="https://www.vnkha.com/search/label/AI">AI</a>
                    <a href="https://www.vnkha.com/search/label/Cloud-dien-toan-dam-may">Cloud</a>
                    <a href="https://www.vnkha.com/search/label/AppSheet">Google AppSheet</a>
                    <a href="https://www.vnkha.com/search/label/Power%20Apps">Power Apps</a>
        </div>
    </div> 

<div class="dropdown">
    <button class="dropbtn">&#9776;
    </button>
             <div class="dropdown-content">
                   <a href="#">Download</a>
                    <a href="#">Giáo trình</a>
                    <a href="#">Biểu mẫu</a>
                    <a href="#">Thi trắc nghiệm</a>
                    <a href="#">Chấm trắc nghiệm</a>
                    
        </div>
    </div> 
   
</div>Copy

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