使用HTML5和CSS3制作登录页面完整步骤

HTML5 和 CSS3 制作一个登录页面的完整过程。

login.html

 1 <form id="login">
 2     <h1>Log Inh1>
 3     <fieldset id="inputs">
 4         <input id="username" type="text" placeholder="Username" autofocus required>
 5         <input id="password" type="password" placeholder="Password" required>
 6     fieldset>
 7     <fieldset id="actions">
 8         <input type="submit" id="submit" value="Log in">
 9         <a href="">Forgot your password?a><a href="">Registera>
10     fieldset>
11 form>

所用到的 HTML5 的特性：

placeholder – 输入框的简短提示，当该输入框获得输入焦点时，该提示信息自动消失
required – 指定该输入元素是否必须提供
autofocus – 指定输入框是否在页面加载完毕自动获取输入焦点
type=”password” – 指定密码输入（非HTML5专有）

CSS

在这里我们用到了 CSS3 的一些专有属性，包括：

Box-shadow 可以帮我们制作效果很好的边框阴影

#login
{
    box-shadow:
          0 0 2px rgba(0, 0, 0, 0.2),
          0 1px 1px rgba(0, 0, 0, .2),
          0 3px 0 #fff,
          0 4px 0 rgba(0, 0, 0, .2),
          0 6px 0 #fff,
          0 7px 0 rgba(0, 0, 0, .2);
}

Stitch effect （缝效果）

#login
{
    position: absolute;
    z-index: 0;
}

#login:before
{
    content: \'\';
    position: absolute;
    z-index: -1;
    border: 1px dashed #ccc;
    top: 5px;
    bottom: 5px;
    left: 5px;
    right: 5px;
    -moz-box-shadow: 0 0 0 1px #fff;
    -webkit-box-shadow: 0 0 0 1px #fff;
    box-shadow: 0 0 0 1px #fff;
}

Subtle gradient lines （微妙的渐变线）

h1
{
    text-shadow: 0 1px 0 rgba(255, 255, 255, .7), 0px 2px 0 rgba(0, 0, 0, .5);
    text-transform: uppercase;
    text-align: center;
    color: #666;
    margin: 0 0 30px 0;
    letter-spacing: 4px;
    font: normal 26px/1 Verdana, Helvetica;
    position: relative;
}

h1:after, h1:before
{
    background-color: #777;
    content: "";
    height: 1px;
    position: absolute;
    top: 15px;
    width: 120px;
}

h1:after
{
    background-image: -webkit-gradient(linear, left top, right top, from(#777), to(#fff));
    background-image: -webkit-linear-gradient(left, #777, #fff);
    background-image: -moz-linear-gradient(left, #777, #fff);
    background-image: -ms-linear-gradient(left, #777, #fff);
    background-image: -o-linear-gradient(left, #777, #fff);
    background-image: linear-gradient(left, #777, #fff);
    right: 0;
}

h1:before
{
    background-image: -webkit-gradient(linear, right top, left top, from(#777), to(#fff));
    background-image: -webkit-linear-gradient(right, #777, #fff);
    background-image: -moz-linear-gradient(right, #777, #fff);
    background-image: -ms-linear-gradient(right, #777, #fff);
    background-image: -o-linear-gradient(right, #777, #fff);
    background-image: linear-gradient(right, #777, #fff);
    left: 0;
}