<h1>通讯录</h1> <button class="add-btn">添加联系人</button> <table> <thead> <tr> <th>姓名</th> <th>电话</th> <th>邮箱</th> <th>操作</th> </tr> </thead> <tbody> <!-- 数据渲染 --> </tbody> </table> <!-- 弹出层，用于添加或编辑联系人 --> <div id="modal" style="display: none;"> <form> <div class="form-group"> <label for="name">姓名</label> <input type="text" id="name" name="name" required> </div> <div class="form-group"> <label for="phone">电话</label> <input type="text" id="phone" name="phone" required> </div> <div class="form-group"> <label for="email">邮箱</label> <input type="text" id="email" name="email" required> </div> <button id="save-btn">保存</button> <button id="cancel-btn">取消</button> </form> </div>帮我给这个页面用JavaScript和css3美化一下

好的，下面是一个简单的示例代码，你可以根据自己的需要进行修改：

HTML：

<h1>通讯录</h1>
<button class="add-btn">添加联系人</button>
<table>
  <thead>
    <tr>
      <th>姓名</th>
      <th>电话</th>
      <th>邮箱</th>
      <th>操作</th>
    </tr>
  </thead>
  <tbody>
    <!-- 数据渲染 -->
  </tbody>
</table>

<!-- 弹出层，用于添加或编辑联系人 -->
<div id="modal" class="modal" style="display: none;">
  <div class="modal-content">
    <span class="close">&times;</span>
    <form>
      <div class="form-group">
        <label for="name">姓名</label>
        <input type="text" id="name" name="name" required>
      </div>
      <div class="form-group">
        <label for="phone">电话</label>
        <input type="text" id="phone" name="phone" required>
      </div>
      <div class="form-group">
        <label for="email">邮箱</label>
        <input type="text" id="email" name="email" required>
      </div>
      <button id="save-btn">保存</button>
      <button id="cancel-btn">取消</button>
    </form>
  </div>
</div>

CSS：

/* 弹出层样式 */
.modal {
  display: none; /* 默认隐藏 */
  position: fixed;
  z-index: 1;
  left: 0;
  top: 0;
  width: 100%;
  height: 100%;
  overflow: auto;
  background-color: rgba(0, 0, 0, 0.4); /* 添加半透明背景 */
}

.modal-content {
  background-color: #fefefe;
  margin: 10% auto;
  padding: 20px;
  border: 1px solid #888;
  width: 40%;
}

.close {
  color: #aaa;
  float: right;
  font-size: 28px;
  font-weight: bold;
}

.close:hover,
.close:focus {
  color: black;
  text-decoration: none;
  cursor: pointer;
}

/* 表格样式 */
table {
  border-collapse: collapse;
  width: 100%;
}

th, td {
  text-align: left;
  padding: 8px;
}

th {
  background-color: #4CAF50;
  color: white;
}

tr:nth-child(even) {
  background-color: #f2f2f2;
}

tr:hover {
  background-color: #ddd;
}

/* 按钮样式 */
button {
  background-color: #4CAF50;
  color: white;
  border: none;
  padding: 10px;
  margin: 5px;
  cursor: pointer;
}

button:hover {
  background-color: #3e8e41;
}

/* 表单样式 */
.form-group {
  margin-bottom: 10px;
}

label {
  display: block;
  margin-bottom: 5px;
  font-weight: bold;
}

input[type=text] {
  width: 100%;
  padding: 10px;
  border-radius: 3px;
  border: 1px solid #ccc;
  box-sizing: border-box;
}

button#save-btn {
  background-color: #4CAF50;
  color: white;
  border: none;
  padding: 10px 20px;
  margin-top: 10px;
  cursor: pointer;
}

button#cancel-btn {
  background-color: #ccc;
  color: white;
  border: none;
  padding: 10px 20px;
  margin-top: 10px;
  cursor: pointer;
}

button#save-btn:hover {
  background-color: #3e8e41;
}

button#cancel-btn:hover {
  background-color: #bbb;
}

JavaScript：

// 获取元素
var modal = document.getElementById("modal");
var addBtn = document.querySelector(".add-btn");
var closeBtn = document.querySelector(".close");

// 点击添加联系人按钮，弹出添加联系人窗口
addBtn.addEventListener("click", function() {
  modal.style.display = "block";
});

// 点击关闭按钮或者弹出层之外的区域，关闭弹出层
closeBtn.addEventListener("click", function() {
  modal.style.display = "none";
});

window.addEventListener("click", function(event) {
  if (event.target == modal) {
    modal.style.display = "none";
  }
});