Html 之登录界面

编写代码

<!DOCTYPE html>
<html lang="en">
<head>
    <meta charset="UTF-8">
    <meta name="viewport" content="width=device-width, initial-scale=1.0">
    <title>Document</title>
    <link rel="stylesheet" href="https://stackpath.bootstrapcdn.com/bootstrap/4.3.1/css/bootstrap.min.css" >
    <link href="floating-labels.css" rel="stylesheet">
    <style>
        .bd-placeholder-img {
            font-size: 1.125rem;
            text-anchor: middle;
        }
  
        @media (min- 768px) {
            .bd-placeholder-img-lg {
            font-size: 3.5rem;
            }
        }

        html,
        body {
            height: 100%;
        }

        body {
            display: -ms-flexbox;
            display: flex;
            -ms-flex-align: center;
            align-items: center;
            padding-top: 40px;
            padding-bottom: 40px;
            background-color: #f5f5f5;
        }

        .form-signin {
             100%;
            max- 420px;
            padding: 15px;
            margin: auto;
        }

        .form-label-group {
            position: relative;
            margin-bottom: 1rem;
        }

        .form-label-group > input,
        .form-label-group > label {
            height: 3.125rem;
            padding: .75rem;
        }

        .form-label-group > label {
            position: absolute;
            top: 0;
            left: 0;
            display: block;
             100%;
            margin-bottom: 0; /* Override default `<label>` margin */
            line-height: 1.5;
            color: #495057;
            pointer-events: none;
            cursor: text; /* Match the input under the label */
            border: 1px solid transparent;
            border-radius: .25rem;
            transition: all .1s ease-in-out;
        }

        .form-label-group input::-webkit-input-placeholder {
            color: transparent;
        }

        .form-label-group input:-ms-input-placeholder {
            color: transparent;
        }

        .form-label-group input::-ms-input-placeholder {
            color: transparent;
        }

        .form-label-group input::-moz-placeholder {
            color: transparent;
        }

        .form-label-group input::placeholder {
            color: transparent;
        }

        .form-label-group input:not(:placeholder-shown) {
            padding-top: 1.25rem;
            padding-bottom: .25rem;
        }

        .form-label-group input:not(:placeholder-shown) ~ label {
            padding-top: .25rem;
            padding-bottom: .25rem;
            font-size: 12px;
            color: #777;
        }

        /* Fallback for Edge
        -------------------------------------------------- */
        @supports (-ms-ime-align: auto) {
        .form-label-group > label {
            display: none;
        }
        .form-label-group input::-ms-input-placeholder {
            color: #777;
        }
        }

        /* Fallback for IE
        -------------------------------------------------- */
        @media all and (-ms-high-contrast: none), (-ms-high-contrast: active) {
        .form-label-group > label {
            display: none;
        }
        .form-label-group input:-ms-input-placeholder {
            color: #777;
        }
        }

    </style>
</head>
<body>
    
    <form class="form-signin">
        <div class="text-center mb-4">
            <img class="mb-4" src="img/img1.jpg" alt="" width="72" height="72">
            <h1 class="h3 mb-3 font-weight-normal">User login</h1>
            <!-- <p>Build form controls with floating labels via the <code>:placeholder-shown</code> pseudo-element. <a href="https://caniuse.com/#feat=css-placeholder-shown">Works in latest Chrome, Safari, and Firefox.</a></p> -->
        </div>
      
        <div class="form-label-group">
            <input type="email" id="inputEmail" class="form-control" placeholder="Email address" required="" autofocus="">
            <label for="inputEmail">Email address</label>
        </div>
      
        <div class="form-label-group">
            <input type="password" id="inputPassword" class="form-control" placeholder="Password" required="">
            <label for="inputPassword">Password</label>
        </div>
      
        <div class="checkbox mb-3">
            <label>
                <input type="checkbox" value="remember-me"> Remember me
            </label>
        </div>
        <button class="btn btn-lg btn-primary btn-block" type="submit">Sign in</button>
        <p class="mt-5 mb-3 text-muted text-center">© 个人网站登陆系统</p>
    </form>

    <form class="form-signin">
        <div class="text-center mb-4">
            <img class="mb-4" src="img/img2.jpg" alt="" width="72" height="72">
            <h1 class="h3 mb-3 font-weight-normal">User login</h1>
            <!-- <p>Build form controls with floating labels via the <code>:placeholder-shown</code> pseudo-element. <a href="https://caniuse.com/#feat=css-placeholder-shown">Works in latest Chrome, Safari, and Firefox.</a></p> -->
        </div>
      
        <div class="form-label-group">
            <input type="email" id="inputEmail" class="form-control" placeholder="Email address" required="" autofocus="">
            <label for="inputEmail">Email address</label>
        </div>
      
        <div class="form-label-group">
            <input type="password" id="inputPassword" class="form-control" placeholder="Password" required="">
            <label for="inputPassword">Password</label>
        </div>
      
        <div class="checkbox mb-3">
            <label>
                <input type="checkbox" value="remember-me"> Remember me
            </label>
        </div>
        <button class="btn btn-lg btn-primary btn-block" type="submit">Sign in</button>
        <p class="mt-5 mb-3 text-muted text-center">© 个人网站登陆系统</p>
    </form>



    <script src="https://code.jquery.com/jquery-3.3.1.slim.min.js" ></script>
    <script src="https://cdnjs.cloudflare.com/ajax/libs/popper.js/1.14.7/umd/popper.min.js" ></script>
    <script src="https://stackpath.bootstrapcdn.com/bootstrap/4.3.1/js/bootstrap.min.js" ></script>
</body>
</html>
Html 之登录界面

编写代码

运行结果
