输入框边框渐变实现及自动补全禁用问题求助

1. 实现完整边框渐变效果 #

你当前的边框渐变仅显示边角，原因是border-image属性缺少border-image-slice配置。修改#input:focus的CSS规则，添加border-image-slice: 1即可让渐变铺满整个边框：

#input:focus {
  outline: none;
  border: solid 2px;
  border-image: linear-gradient(90deg, #0cebeb, #20e3b2, #29ffc6) 1;
  border-radius: 0px;
}

border-image-slice: 1会将渐变图像的边缘切割为1像素单位，拉伸后覆盖整个边框区域，解决边角显示的问题。

2. 禁用输入框自动补全 #

给input标签添加autocomplete="new-password"属性（该属性对现代浏览器兼容性更强，部分浏览器会忽略autocomplete="off"）：

<input type="text" id="input" autocomplete="new-password" oninput="this.style.width = 0; this.style.width = this.scrollWidth + 'px'" placeholder="Enter an activity...">

修改后的完整代码 #

HTML

<p id="title" title="To do list">To Do List</p>
<div class="container">
  <form action="javascript:toElement()">
    <input type="text" id="input" autocomplete="new-password" oninput="this.style.width = 0; this.style.width = this.scrollWidth + 'px'" placeholder="Enter an activity...">
    <button id="submit" type="submit">Add</button>
  </form>
</div>

<ul id="list">
  <li id="obj_1">Test 1</li>
  <li id="obj_2">Test 2</li>
  <li id="obj_3">Test 3</li>
  <li id="obj_4">Test 4</li>
  <li id="obj_5">Test 5</li>
</ul>

CSS

@import url('https://fonts.googleapis.com/css2?family=Raleway:wght@300&display=swap');
body {
  background: rgb(255, 255, 255);
  background: -moz-linear-gradient(90deg, rgba(255, 255, 255, 1) 0%, rgba(174, 174, 174, 1) 100%);
  background: -webkit-linear-gradient(90deg, rgba(255, 255, 255, 1) 0%, rgba(174, 174, 174, 1) 100%);
  background: linear-gradient(90deg, rgba(255, 255, 255, 1) 0%, rgba(174, 174, 174, 1) 100%);
  filter: progid:DXImageTransform.Microsoft.gradient(startColorstr="#ffffff", endColorstr="#aeaeae", GradientType=1);
  user-select: none;
}

#title {
  font-family: 'Raleway', sans-serif;
  font-size: 50px;
  margin-top: 5%;
  font-weight: bold;
  text-align: center;
}

#input {
  min-width: 270px;
  height: 40px;
  border: none;
  font-family: 'Raleway', sans-serif;
  font-weight: bold;
  font-size: 25px;
  padding-left: 25px;
  padding-right: 25px;
  text-align: center;
  outline: none;
}

#input:focus {
  outline: none;
  border: solid 2px;
  border-image: linear-gradient(90deg, #0cebeb, #20e3b2, #29ffc6) 1;
  border-radius: 0px;
}

.container {
  display: flex;
  align-items: center;
  justify-content: center;
}

JavaScript

function toElement() {
  var z = document.getElementById("input").value;
  if (z == "") {
    return
  }
  var x = document.createTextNode(z)
  var y = document.createElement("li");
  y.appendChild(x);
  document.getElementById("list").appendChild(y);
  document.getElementById("input").value = '';
  var a = document.getElementById("input")
  a.style.width = 270 + 'px';
}

内容的提问来源于stack exchange，提问作者Fieryfeng